Aurora 2010 (GIKI Science Society Magazine)

scienceaurora

S O C I E T Y

Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

ExclusiveInterview:

2010

Modern Materials:The EmergingTechnology

scienceaurora 201004 The Eight Astounding Materials of Today

09 Cellular Phone Jamming Eradicating Electro Pollution

12 Going Nano: Digging Parallel with Nokia Morph

14 The Road to ToE Theory of Everything

19 Cranial Electrotherapy For Stimulating Human Brain27 Exclusive Interview: Dr. Samar Mubarakmand

32 Micro Wind Turbines: Sustainable Solution for Meeting Energy Crisis

36 Science World: What is happening in the science world?

38 Smaller Beta Decay Rates of Iron Isotopes for Supernova Physics

40 Imaging Capability of PHEMT, AlGaN/GaN and Si Micro Hall Probes for Scanning Hall Probe Microscopy

43 Final Year Project Abstracts

46 Science Society’s Activities

48 The GIKI Science Society

The Crab Nebula, is a supernova remnant and pulsar wind nebula in the constellation of Taurus.

22 BRINGING DARK SECRETSTO LIGHT:

A GIKI Science SocietyPublicationwww.giki.edu.pk/[email protected]

©

2010 · SCIENCE AURORA · GIKI

COVER STORY

What if Dark Forces of Nature don’t exist?

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The ancient men, with their unstructured methods of alchemy, herbology, lore and mysticism were doing the same thing that science does nowadays – try to understand their world, and to mould it to their requirements. But with the added structure, science has become all enveloping. And whereas it now covers natural, social and behavioral, applied, and formal aspects, the primal incarnation of hu-man knowledge we simply call science has become a fundamental in normal life.It was with this relevance that when GIKI was made for the dissemination of structured knowledge, the seed of the GIKI Science Society was laid. And it is for the same reason you hold this magazine, the Science Society’s production of a year of hard work, in your hands – science instructs us, it interests us, and it even fascinates us. In producing this magazine’s 3rd volume, it is those facets that we have kept in mind.The Aurora, also known as the borealis, is a beautiful natural phenomenon, and a wondrous spectacle of many colours and lights. This Aurora, likewise, attempts to be a brilliant collection of knowledge from the scientific world. It tries to be informative, instructive, interesting, and sometimes humorous, but always captivating.The GIKI Science Society’s Aurora, then, is a testament to an exceptional team of students who have strived to present often oblique scientific knowledge from various disciplines in a tightly linked, di-gestible form. Having said that, it would be a crime to keep you from exploring the magazine any further.Read, enjoy, and absorb. Remember, feedback is always welcome!Editor in ChiefMuhammad Fahd Waseem

EditorialEditorial

The TeamThe Aurora TeamFaculty Advisor: Dr. Rizwan AkramPresident: Haseeb Ahmed QureshiHonorary Editor: Faizan Ahmed Siddique

Design & Creative Director: Ameer Hamza JanjuaDirector Publications: Khubaib KhanDirector Finance: Ahmed SaleemDirector Marketing: Farwa Imam

Editorial Directors:Hira KaleemFaizan RasoolAreeb KamranM. Omar Waqar Mir Durriya ZarrarSyed M. AliEzza Javed

Technical Team:Mohsin JawadUsman ZafarHassan ZaheerWaleed

The Science Society has been amongst one of the most active technical societies of the GIK institute for the last decade. They organize a culmination of events for the student community of the Institute imparting scientific knowledge and new developments in a fun-oriented manner. Aurora, the magazine by the Science Society, has been compiled by its members through devotion, diligence and sincere hard work. I have found the magazine

very informative and interesting. The interview of Dr. Samar Mubarakmand provides an insight of the atomic odyssey of Pakistan. It was by far the most interesting read of Aurora. I congratulate the mem-bers of the society on coming up with an excellent contribution to the GIKI campus life. I hope that you will enjoy reading aurora as much as I have, or may be more.Prof. Dr. Fazal Ahmed Khalid (SI)Pro-Rector (Academics)

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Dean Student Affairs

Pro RectorMessage From Pro Rector

Message From DSAScience society at GIKI has been playing a critical role in promoting and enriching the knowledge of students nationwide. It has organized 11 All-Pakistan events up-to-date, creating a competitive platform for Pakistani students at school and university levels. Furthermore, it has established the tradition of printing Aurora magazine throughout Pakistan, enlightening students and adults alike.

I have found Aurora a stimulating and capturing read, a collection of educated articles contributed by many GIKI students. It addresses topics ranging from the foremost frontier of science to dealing with the environment and energy crisis. Especially of importance for today’s energy demands is the use of micro wind turbines which is explored in one of the articles. Moreover, intriguing concepts of Dark Matter and Energy force us to experience a paradigm shift in our view of the universe. In short, the efforts put into Aurora by the GIKI Science Society are to be congratulated. Dr. Mohammad Sultan KhanDean Student Affairs

Faculty AdvisorMessage From AdvisorThe GIKI Science Society is a very active society in organizing events that bring students closer to scientific knowledge without causing boredom. Aurora is another step towards that. Aurora contains articles from various students of the institute. It contains a diverse mixture of articles ranging from recent technologies and prototype inventions to those that question the existence of human life. The interview of Dr. Samar Mubarakmand is very informative and motivating. Reading this interview made me go down the memory

lane a decade ago. With the lines of the interview, I travelled through the journey of a man whose tri-umphs were the most celebrated scientific glories of a nation. Aurora is a brilliant effort by the highly dedicated members of the Science Society. I praise them on their efforts in publishing The Aurora.Dr. Rizwan AkramFaculty Adivisor GIKI Science Society

The EightAstounding Materialsof Today

Historically, eras have been named after particular advance-ments of that age. The Iron Age, the Bronze Age, the Civi-lized Age, the Renaissance, the Industrial Revolution, the

Information Age and so on. The current age is very probably the Age of Awesome Materials.Scientists have been churning out substances that promise to change our lives – much like computers and electronics did for the generations before us. But these materials are not basic step ups over previous designs. In other words, some of the materi-als being developed are not only evolutionary, but revolutionary.It is only fitting, then, that we pay a tribute to the advance of science and roll out a list of 8 forms of substance that seem to defy physics, and bend our minds about how we work with materials. These are, of course, presented in no particular order. The fine details have been sacrificed in favour of salient features.

We pay a tribute to the advance of science and roll out a list of 8 forms of sub-stance that seem to defy physics.

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By Muhammad Fahd WaseemBatch 17

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Aerogels

Aerogel is a manufactured material with the lowest bulk density of any known porous solid. It is basi-cally a gel from which the liquid has been replaced by a gas. This gives extremely low densities, but ex-treme strength. In appearance, it is very much like a faintly translucent piece of plastic – in fact, it is often referred to as ‘solid smoke’. The compressive properties are stunning: 2 grams of aerogel can sup-port over 25 Newtons of force. Imagine a wisp of smoke supporting a brick, and you get an image so definitive, it is on Wikipedia. Moreover, most aero-gels are extremely good thermal insulators. Some are practically fireproof.

Image showing microscopic structure of Aerogel.

Perflurocarbons

Perfluorocarbons (PFCs) are fluorocarbons, com-pounds derived from hydrocarbons by replacement of hydrogen atoms by fluorine atoms. Chemically and thermally stable, they are extremely good sol-vents for gases and have very low refractive in-dexes.They are used in imaging applications and eye sur-gery due to their refractive index, but their most interesting use, by far, is in liquid breathing. They dissolve massive amounts of air and oxygen. This is one liquid you would never drown in if it were pure enough.Perhaps the LCL Sea in the Neon Genesis series was not so science fiction after all.

Uses vary from the NASA space suits (which are filled with it to provide protection against extreme space temperatures) to simple, shatterproof, insula-tion window glass.Next time your house needs an oven, demand one made of aerogels. Think how much cooler it would be.

Ferrofluids

A ferrofluid is a liquid which becomes strongly po-larised in the presence of a magnetic field. On the application of the right magnetic field, these fluids (which are colloidal suspensions of ferromagnetic materials) can assume many different shapes. They absorb magnetic radiation, and in some cases so-lidify in the presence of a magnetic field.

A ferrofluid in shape of a magnetic field.

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Their unique abilities allow for some rather amaz-ing uses. This is one of the materials used in the top secret aircraft coating mix used by the US Air Force for their stealth jets like the B2 or the F117. They are used as lubricants whenever magnets are used

in mechanical en-gineering. They are used as liquid heat conductors – rather like heat buses.In some museums, they are used as art. I can well imagine: shiny black fluid moving around in a most delicatessen like manner and as-suming the shape of the magnetic field they are in.

A ferrofluid - Under effect of a magnet.

Metamaterials

Metamaterials are artificial materials engineered to provide properties which “may not be readily available in nature”. These materials usually gain their properties from structure rather than composition, using the inclu-sion of small inhomogeneities to en-act effective macroscopic behavior. Most research in this area is focused around light bending metamaterials – materials with a negative refrac-tive index.The most hyped use for such meta-materials, obviously, is in invisibil-ity cloaks. The military wants it for their soldiers, and medical profes-sionals want it for conducting social research. Superlenses and spectacles that let you see through the back of your head are just some of the uses being thought up as this field of ma-terials advances.I want one of those cloaks too.

To be more accurate, transparent metal alloys. There are many metallic crystals in nature that are transparent (some precious gems are included) but science has now managed to replicate them. Special combinations of aluminum (and some other metals) and crystal structure make it invisible to hard elec-tromagnetic radiation such as X and Gamma Rays. As a side effect, they also become invisible to most of the visible spectrum i.e. transparent. They act like normal metals – good conductors, sonorous, strong and even slightly malleable – but are see-through.Their primary use would be wherever really tough glass is required. Think airplane windows, bunker sunroofs and submarine porthole. On the more mundane side, they could be used as a replacement for car side windows screens.Twenty years into the future and burglars will have to find a way into a house other than breaking the windows.

A computer generated simulation of structure of metamaterial.

Transparent Metals

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Elastic Conductors

Elastic conductors are (generally) made from em-bedding organic or mineral semiconductors onto thin silicone sheets that have been pre-treated with ionic liquids. The result is a bendable, stretchy,

rubber-like, almost transparent sheet that is not only conductive, but extremely thin and printable with embed-ded circuits. Think: an electronic plastic sheet.The uses are numer-ous, but the most revo-lutionary change could

be the threat they pose to the hand written word on paper. If they become cheap enough, and advanced enough (and the direction is already right), they could replace paper for good. Imagine: a newspaper that updates itself every day, a note-book that consists of one page only and a book that you never have to buy. Add to it other uses, such as ‘skin’ for robots, or wearable circuits, and the possibilities for elastic conductors are limitless.Classrooms will never recover from the blow if you can watch YouTube in your class register.

Non-Newtonian Fluids

A non-Newtonian fluid is a fluid whose flow properties are not described by a single con-stant value of viscosity. Many polymer solu-tions and molten polymers are non-newtonian fluids, as are many commonly found substanc-es such as ketchup, starch suspensions, paint, blood and shampoo. The difference, however, is in how greatly non-newtonian some of the newly developed fluids are.

Most of these fluids react to exerted force and strain, but some actually solidify for short dura-tions during the impulse of the force, or vice versa. The military, as always, would find a use for it in bulletproof jackets as bullets would solidify the fluid by proportion to the force they exert (result: dead bullet). They find other uses too, for example, in hydraulic mechanisms or non-drip paints.Walking on liquid was never easier – just make

sure it solidifies by the pressure your foot exerts. Otherwise, it could be a drowning case; after all, perfluorocarbons are not non-newtonian.

Carbon Nanotubes

It would not be wrong to say that carbon nano-tubes are easily one of the top materials under development. They are allotropes of carbon with a cylindrical nanostructure. They ex-hibit extraordinary strength (tensile strength is the highest known for any material ever) and unique electrical properties (lengthwise, they are far better conductors than any known metal at room temperature). Single strands about the width of a human hair could life entire trucks; or replace the bulky high tension wires. They are also efficient conductors of heat. Surpris-ingly, they are a by-product of innocent arc welding. They are also, unfortunately, toxic to humans at cellular level. Moreover, they are very difficult to mass produce or string togeth-er in macroscopic lengths.

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The uses are abundant. Everything around you could be affected – nearly every single thing around you could be lighter, tougher, less breakable, and more efficient by many magnitudes if they were made of carbon nanotubes. So far, scientists have managed to make super-small computer proces-sors and low-resis-tance circuitry. In the future, all bets are off. Tiny super-computers. Even ti-nier, super-efficient batteries. Really ef-ficient solar panels. Paper-thin materi-als that can stop a bullet. Sunglasses hinges that never break. Toasters that get the toast right every time. TV remotes where the numbers do not wear off the buttons. Ceiling fans that do not vibrate.

Bags of chips that never get stuck in the vending ma-chine. Carbon nanotubes will solve it all. Some of the top prizes in science are being awarded to those who advance in this field.I must stop writing this ar-ticle. I better do some re-

search on nanotubes if I want that Nobel prize.

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Cell Phone Jamming (prohib-ited in most countries) is an effective technique to main-tain peace in areas where cell phones are not necessary with-out bothering users to switch off their phones.By: Faisal Mahmood

Modern cell phones accompanying polyphonic ring tones and multimedia options are being used commonly in those areas where there usage should be prohibited such as lecture halls, holy places, conferences and meet-ing rooms. Moreover cell phones are a big cause of electro pollution, exposure of electromagnetic radiation directly to the ear which is quite near to the brain can be extremely dangerous. Cell phone jamming (prohib-ited in most countries) is an effective technique to maintain peace in areas where cell phones are not necessary without bothering users to switch off their phones. Mostly such devices are costly and it is difficult to get hold of them in underdeveloped and developing countries. Most of the cell phone jamming designs require use of inductors or such components which are difficult to tune, these components make these devices expensive and difficult to acquire.

Cellular Phone Jamming:Eradicating Electro Pollution

An Introduction to the Most Simple Design

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DIFFERENT TECHNIQUES USED FORJAMMING:

Five types of devices are known to have been de-veloped (or being considered for development) for preventing mobile phones from ringing in certain specified locations.

A. Type “A” Device (JAMMERS):This type of device comes equipped with several independent oscillators transmitting ’jamming sig-nals’ (noise) capable of blocking frequencies used by paging devices as well as those used by cellular systems control channels for call establishment. The implementation of such a device is very sim-ple and will be further considered in the design.

B. Type “B” Device (Intelligent Cellular Dis-ablers):Unlike jammers, type B devices do not transmit an interfering signal on the control channels. The device, when located in a designated ’quiet’ area, functions as a ’detector’. It has a unique identifica-tion number for communicating with the cellular base station, informing that the user is in a quiet room and block all calls and messages, however as an intelligent device it may allow emergency calls.

C. Type “C” Device (Intelligent Beacon Dis-ablers):Unlike jammers, type C devices do not transmit an interfering signal on the control channels. The device when located in a designated ’quiet’ area, interact with the cellular device and instructs it to disable its ringer operation.

D. Type “D” Device (Direct Receive & Transmit Jammers): This jammer behaves like a small, independent and portable base station, which can directly interact intelligently or unintelligently with the operation of the local mobile phone. The jammer is predomi-nantly in receive mode and will intelligently choose to interact and block the cell phone directly if it is within close proximity of the jammer.

E. Type “E” Device (EMI Shield - Passive Jam-ming):‘EMI Shield – Passive Jamming’. This technique uses Electro Magnetic Interference (EMI) suppres-sion techniques to construct what is called a Fara-day cage. The Faraday cage essentially blocks, or greatly attenuates, virtually all electromagnetic ra-diation from entering or leaving the cage.Although labour intensive to construct, the Faraday cage es-sentially blocks or greatly attenuates, virtually all electromagnetic radiation from entering or leaving the cage.

PRINCIPLE OF DESIGNThe basic principle was to generate white noise by using a Zener diode and amplify it by using an audio amplifier. This amplified noise is then summed with a triangular wave, and then the wave from (noise summed on triangular wave) is set to vary from 1V to 5V which is the requirement of the VCO (Voltage Control Oscillator) to generate frequency of 930 MHz to 970 MHz (covering GSM 900 Downlink range), the output of the VCO is of about 3.5 to 5 dBm which is amplified using a power amplifier to 34dBm and then it is transmitted using a GSM 900 antenna.

DETAIL OF THE DESIGNThere are two major sections of the design the IF section which produces the wave to tune the VCO (Voltage Control Oscillator) in the RF section. First we consider the IF section, our objective in this section was to produce a noisy triangular wave which we could use to tune the VCO, the reason to use the triangular wave is that the VCO could vary its frequency between 925MHz to 970MHz

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(GSM downlink) so it can cover the entire spectrum band.

RESULTS & CONCLUSIONS After completing the whole design process the results appeared positive we were able to jam ap-proximately 20m radius around our jamming sys-tem. The design is significantly cost effective and simple. The following figure shows the output of the jammer on a spectrum analyzer the peak shows that we have jammed from 925-970 MHz which is the GSM downlink frequency. The effectiveness of the design is that it is so simple that now cell phone jammers can be easily produced at low cost in Paki-stan and can be made available for holy places, hos-pitals, universities, etc;where there is dire need to install them due to growing electro-pollution.

The matlab simulation is quite similar to our prac-tical result obtained over the spectrum analyser.

Further Reading: Comparative Analysis of Different Cellular Phone Jamming Techniques, Implementation of The Most Efficient & Cost Effective Design & Its Ex-tension for Jamming of Specific Operators By: F. Mahmood published at UCP IEEE Multi Topic Conference ‘09.

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By: Mohtasham KhanBatch 17

GOING NANO

Digging Parallelwith Nokia MorphIf the cell phone giant is to be born again, na-

no-science might be its only chance. Like all technological advancements, nanotechnolo-

gy has been subjected to dynamic overstatement, speculation and opposition. The chain of discov-eries leave us at once awed by new possibilities and at beset by questions.There are many companies selling all sorts of nanotubes. ‘Nano’ is today’s word. Even the White House understands it, (naming five cat-egories: dendrimers, quantum dots, CNTs, fuller-enes, nanowires) and has already invested bil-lions of dollars in research.Last year Nokia exhibited a very unique con-cept in the New York Museum of Modern Art and called it Morph. This unique vision utilizes Nano Technology applications to completely alter the future of today’s cell phone. Nokia Research Centre and Cambridge Nanosci-ence Centre are jointly working on the concept that might shake many communication giants.Nokia was able to demonstrate a flexible design that was equipped with advanced power sources, had remarkable sensors embedded and was able to clean itself.

A flexible design will enable the device to transform into desired/known shape. Fibril proteins will weave themselves in 3-D structure and have ability to form up to the length of micrometers while retaining their nano scale diameter. Morph will capacitate the devise to wrap or fold according to desired parameters and serve as an iPod while jogging, a bracelet during par-ty, or a photo frame on a desktop as the need may be.Morph also induces a self cleaning concept in a tra-ditional communication device. ‘Nanoflowers’, also developed in Nanoscience Centre (Cambridge), will enable the device to be water and dust repellent.Possible upgrades might include pre-sensing of ad-vanced chemical and biological environments which may lead to win Nokia some military contracts or make it a super producer of medical technology goods.Morph will be powered by nanograss, which com-prises of tunable nanostructured surfaces. The be-havior of these surfaces can be reversibly altered between hydrophilic and hydrophobic phases either actively, by the application of electrical voltage, or passively, in response to the change in environmental conditions such as humidity.

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Sensors are new ingredients to cell phone recipe. So far, the iPhone’s accelerometer, proximity and ambient light sensors are amongst the most ef-ficient and widely used sensors in public domain devices. Nokia takes it to the next level: Morph is propelled by highly efficient nano sensors that gains access to, and manipulates the user’s envi-ronment. Dynamic AI is triggered and decisions are made. Nokia also released an animated video showing how sensors would work and warn in a polluted environment. All the sensing is maneu-vered in the nano environment. Because of all that, critics are also considering the Morph concept to

the answer to Green Peace Agenda. Green peace is an organization for environmental conserva-tion which criticizes Nokia over its environmen-tal practices. It is notable that, after one week of release of the Nokia report, “Nokia Evolve”, ”Nokia Sensor Concept”, ”Nokia Remade” and “Nokia Morph” were promoted to the top of a Green peace list of environmental friendly con-cepts. The Nano Morph will be a breakthrough in de-sign and implementation. Simultaneously, it may catapult Nokia to the center of the world’s tech-nology playing field.

The Concept; which was unveiled on February 25, 2008 at The Museum of Modern Art in New York City.

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GENERAL RELATIVITY

In 1906, in a spectacular stroke of genius, Einstein resolved the seeming conflict between the principle of relativity and the constancy of speed of light by introducing the idea of a space-time continuum; a 4-dimensional coordinate system in which time is considered as just another axis like the other three spatial coordinates. This special setting of coordi-nates of the special theory of relativity is known as flat 4-dimensional‘Minkowski space’, as opposed to our more commonly experienced 3-dimensional ‘Euclidean space’. Let us try to understand the dif-ference between the two. In our usual Cartesian coordinate system, the distance between any two points is given by the Pythagorean Theorem as:

ds2 = dx2 + dy2 + dz2

where ‘dx’, ‘dy’ and ‘dz’ represents the difference between x, y and z coordinates of the two chosen points, respectively. Then ‘ds’ defines the distance between these two points in this particular space.

In a similar vein, in the 4-dimensional co-ordinate system of special relativity, where time is also an ordinate and the speed of light itself plays a part in the geometry of space-time, the distance between two points is defined as:

ds2 = dx2 + dy2 + dz2 - cdt2

(where dt is the value of the difference between time co-ordinates)

Such a mathematical definition, defining the con-cept of distance on a set of points is known as a ‘metric’, and such a set of points together form what is known as a ‘metric space’ or simply ‘space’. Just as the Pythagorean Theorem acts as a metric for our commonly experienced Euclidean space, the former mentioned expression is the metric used to measure distance between two points (or ‘events’ as they are called in relativity) in the four dimensional space-time of the special theory of relativity.

From a geometrical point of view, this Minkowskian space-time of special relativity can be regarded to be ‘flat’ or Euclidean in sense that there is no change of geometry at different points in the continuum and since the metric in any 4-D Euclidean space would be very similar. In contrast, for incorporating grav-ity into the concepts of relativity, Einstein had to use a much more complicated form of geometry known as the Riemannian geometry. In the realm of the general theory of relativity, or GR as we shall call it, the metric at every point is defined by the mass and energy content of its surroundings. This gives rise to the concept of curvature of space-time, representing the difference of geometry at different points. It is the movement of bodies through curved space-times that we experience as gravity. What we see as the action of a force on a free-falling body is really the inertial motion of body through a space-time with a curvature. This is clear from the fact that a free-falling body experiences weightless-ness i.e. it feels as if no force is acting on it. It was only by using these ideas that Einstein was able to

The Road To TOE

The holy grail of theoretical physics is to find a single theory that can explain every possible physical occurence in our universe. In fact, it should explain the making and evolution of the universe itself. It is called “Theory of Everything” (TOE). Although the name might sound a bit cliched and dull at best, it is all that it claims to be. It will be able to explain the workings of everything, from elementary particles to clusters of galaxies and the universe as a whole. Here, we will try to understand the basic structure and goal of a TOE and briefly discuss some of the leading contenders to be one, but first, let’s try to understand the most prominent theories of physics that we have already developed. Familiarity with the basic ideas of relativity and quantum theory is assumed.

By: Saim SultanBatch 19Theory Of Everything

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incorporate gravity into the cherished principle of relativity and in fact further it with an even stronger statement now known as the principle of general covariance, which essentially amounts to the say-ing that there is no preferred space-time in nature and that any two different space-times, represent-ing distinct gravitational fields, are equally suitable for description of the laws of physics. It goes on to say that there is also no natu-rally preferred way of associating points in two different space-times, something which, as we shall see, raises serious problems in the develop-ment of a TOE. We should also note that in the absence of any sig-nificant gravitational field, GR defines ex-actly the same geom-etry of space-time as that given by special relativity. Thus, the ‘special’ theory is really just a special case of GR.

QUANTUM MECHANICS

Quantum mechanics (QM) rules the do-main of the extremely small where the laws of classical (aka Newtonian) mechanics break down. As we probe into the smaller and smaller spatial scales, we see an amplification of the quantum ef-fects. This is not to say that it cannot be applied to larger systems only that at such scales classical me-chanics provides a much simpler framework with almost the same accuracy (correspondence prin-ciple). Let’s try to understand its basics. Quantum theory took off with confirmation of Max Planck’s hypothesis that energy appears in discrete chunks called the quanta of energy. Later, the wave par-ticle duality of matter and energy was established in several experiments including the famous single and double slit experiments. This duality stated that particles behave as waves in some situations and as particles in others and none of these two concepts

have unlimited applicability to describe what an elementary ‘particle’ really is. It can really be considered a semantic problem as we have no separate notion to explain this fuzzy existence of a quantum particle. Its wooly nature restricts our knowledge of its state (we shall use the word ‘state’ to mean the values of observables, like po-

sition and momentum, at any given time) to measurement of mere probabilities.

All that we can know about the state of a quantum particle

(we will restrict ourselves to single particle quan-

tum systems) is given by what is known as the wavefunction,Ψ. It is a function of both space and time (and thus re-quires both of them to be pre-defined; something which,

as well shall see, creates serious chal-

lenges in the develop-ment of a TOE). As an

analogy, wavefunction can be compared to the equation

of motion of classical mechanics. Once the equation of motion for a particle

is known, it defines the future state of the par-ticle at any given time (given the particle is iso-lated). However, one major difference in the case of a quantum system is that all the wavefunction spells out for us are probabilities for all the pos-sible quantum states that might be observed upon measurement; no definite answers. Thus, before the act of measurement, the particle is considered to be in a ‘superposition’ of all possible quantum states. What’s more, quantum mechanics even restricts the amount of information we can have about our quantum system even after the act of measurement in the form of Heisenberg’s uncer-tainty principle, which states that at any given time the position and momentum of a particle cannot be measured up to an unlimited precision.

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Why QM and GR will not suffice… and TOE!

Whereas these two theories explain almost all but the most elusive physical phenomena between them, it is an infinitely sad fact that they are mutually in-compatible and conflict at a most fundamental level. While QM explains three of the fundamental forc-es of our universe, namely electromagnetism, the weak force and the strong force, and GR explains the fourth, namely gravity, as of yet, it has proven impossible to put these two together into a consis-tent theory of quantum gravity. strong force, and GR explains the fourth, namely gravity, as of yet, it has proven impossible to put these two together into a consistent theory of quantum gravity. Here is why, with some simplifications: Let us consider a simple quantum system, say a single particle, with a sig-nificant mass, here on Earth. Now since the Earth is a massive body, its effects on space-time cannot be ignored. According to the quantum description of the particle, it is in a superposition of quantum states and thus it can also be in a superposition of positions on Earth (the probability of finding it very far away from Earth exist but is usually extremely small!). This puts us in a conundrum. If we are to define the gravi-tational field of the particle and its interaction with the Earth’s field, we need to know its position. Even though the Earth’s gravitational field can be consid-ered stationary, it is a curved space-time and cannot be considered flat or uniform. Thus different regions of space-time around the Earth have different cur-vatures and thus define completely different space-times. This leads us to only one conclusion, that su-perposition of positions, in this case, really means that our particle is in several different space-times at once, or technically, it is in a superposition of space-times. We might be tempted to equate the different space-times near earth on the account of neighbor-hood, but, that would cheat the principle of general covariance which says that there is to be no naturally preferred identification between two space-times de-fined differently. Now although we can do QM in a flat, pre-defined space-time, the concept of han-dling spacetimes in basic QM does not make sense. This is because the very definitions of superposition,

quantum state and wave function require the space-time to be already defined and fixed. We can see the conflicting results of the two theories, arising from this fundamental disagreement, whenever we apply them to understand any single situation. One such situation is the singularity of a black hole. A black hole singularity is an infinitely dense point in space-time with an extremely strong gravitational field. Its small spatial scale and its huge gravita-tional field begs us to apply both QM and GR to completely understand its workings, but, doing so produces results that simply make no physical sense at all. Similarly QM and GR applied together to understand the beginning of the universe, also thought to be a singularity, produces no useful re-sults either. Apply both QM and GR to completely understand its workings, but, doing so produces results that simply make no physical sense at all. Similarly QM and GR applied together to under-stand the beginning of the universe, also thought to be a singularity, produces no useful results either.This failure of our two great theories to merge points us to look beyond for enlightenment. Now we will try to understand some of the most well established directions that physicists are looking towards for the unification of fundamental laws of nature in a single theory… a TOE!

Relativistic Quantum Field Theories and The Standard Model:

As we saw earlier, whenever gravitational effects are either negligible or are intentionally ignored we enter the domain of the special theory of rela-tivity. In such a case our space-time becomes flat and uniform, meaning that we do not need to con-sider different points on our space-time co-ordinate system to be defined differently. You see it is only the presence of a significant mass or a gravitational field that forces us to define the geometry of each point in space-time a little differently, giving it a curvature, but, as we can see, we do not have this problem in the special theory. Thus, in the absence of gravity, relativity and QM go along beautifully and the resulting theories are what are known as

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relativistic quantum field theories (from here on to be referred as relativistic QFT(s) or just QFT(s)).In QFTs we combine the idea of a classical field with that of quantization. Take electromagnetic waves as an example. Before quantum theory we knew electromagnetic waves to be a manifestation of disturbances in the electromagnetic field. Later, the quantum theory told us that electromagnetic en-ergy can only appear in small chunks, as particles called photons. Thus really these elementary par-ticles, photons, were a manifestation of the elec-tromagnetic field. This idea was carried forward to other elementary particles and it was suggested that with most particles there is a field associated permeating all space and time and the particles are mere excitations of these fields. Furthermore, the incorporation of the idea of quantization into these fields then gave birth to quantum field theories. A quantum field theory that is compatible with the 4-dimensional space-time of special theory of rela-tivity then becomes known as a relativistic QFT. For example, the crown jewel of all experimental and theoretical physics, quantum electrodynamics, de-veloped largely by the famous Richard Feynman, is a relativistic QFT explaining all the interactions be-tween electrons and photons. This theory has been confirmed in labs all over the world to an accuracy of one part in a billion, unmatched by any other the-ory ever conceived by man. Later, the description of weak force was incorporated into QED, by our very own Abdus Salam and two other physicists, Shel-don Glashow and Steven Weinberg, to give us what is known as the ‘electroweak theory’. Similarly, quantum chromodynamics (QCD) is the relativis-tic QFT describing the interactions of quarks (the particles that make up protons and neutrons) and gluons (carriers of strong force). The merger of the electroweak theory and quantum chromodynamics give us what is known as the Stan-dard Model of particle physics, a framework which can explain almost everything that we are possibly ever to encounter in our physical applications. This is the theory that Robert Oerter, a theoretical physi-cist from George Mason University, calls the ‘un-sung Theory of Almost Everything’, but, the ideal of a TOE still remains elusive.

New Frontiers --- SUSY, Stringy Ideas (String and Superstring Theories and M-Theory) and Loop Quantum Gravity:

In trying to quantize the gravitational field, to form a theory of quantum gravity, theoreticians al-ways ended up with theories that produce absurd infinities making no physical sense. Such theories are termed non-renormalizable theories, and the opposite as you can imagine are called renormal-izable theories. It turns out that some QFTs, even those not dealing with gravity, can also be non-renormalizable and it is a difficult task to form the correct QFT describing any a given interaction. This is where symmetry makes life easier.The QFTs and the Standard Model itself, has some very interesting symmetry properties. Un-der the defined symmetry principles of the Stan-dard Model, we can exchange one fermion (one of the two main types of particles, the other being boson) with another fermion and the basic nature of particle interactions in the equations remain the same. Same goes for bosons, but, the interchange of a fermion with a boson, or vice versa, is not al-lowed; this is exactly what supersymmetry (often called SUSY) allows us to do. This makes QFT building much easier. Achieving renormalizability in non-supersymmetric QFTs is much more diffi-cult than in supersymmetric QFTs, but, it comes with a trade off. Supersymmetry very blatantly predicts the existence of a supersymmetric ‘part-ner’ for every observed elementary particle which differs from the original particle in a very specific way. This means that electron has a partner named ‘selectron’, photon comes with a ‘photino’, W and Z bosons with ‘zino’ and ‘wino’ and so on. The problem is none of these supersymmetric partners have ever been observed in our particle accelera-tors or in cosmic rays (the second most important source of elementary particles for us). It is hoped that the new generation of particle accelerators will be able to produce at least a few of these supersymmetric partners. Although that remains to be seen, SUSY has been found to be particu-larly useful in development of some other TOE contenders. As a solution to a particular problem

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arose in a QFT, string theory was born. The basic idea of string theory is to replace the very notion of a point particle with that of a string. Thus an elementary particle becomes a one-dimensional string in space instead of being confined to a single point. This instantly resolves several problems that arise very often in all QFTs. Many infinities vanish and some of the old problems actually even seize to have any meaning in such a theory. Initially, the theory developed dealt only with bosons, required awkward features such as a space-time consisting of 26 dimensions and still had serious problems like allowing tachyonic propagation i.e. faster-than-light travel. The existence of spooky 26 dimensions and tachyonic behavior seemed to have pronounced the end of the whole string concept when SUSY came to its rescue. The incorporation of SUSY into string theory not only cut down the requirement of space-time dimensions to only 11, the problem of tachyonic propagation no longer existed. These theories came to be known as superstring theories. One significant feature of these theories is that graviton, the particle hypothesized to be the quan-tum of a gravitational field, is a natural outcome of the basic structure of the theory, making it a natural candidate for a complete quantum theory of gravity. Now, like QFTs, instead of being just one there are 5 different types of superstring theories, each made for a specific type of string. In the beginning, it was believed that only one of these five theories will pan out to be the correct representation of nature, but, only recently certain fundamental links between all five have been found and these are now considered to be special cases of a more fundamental theory known as the M-Theory (or the Mother Theory) which is still under construction.Loop Quantum Gravity (LQG) tries to address the

problem by giving the very structure of space a ‘foamy’ or discrete existence. Thus space, just like matter or energy is quantized in little pieces! This means that what we experience as continuous space is really a collection of ‘atoms’ of space joined to-gether in a very specific mathematical way. Such an ‘atom’ of space is the smallest volume that can be given any physical meaning and the notion of any-thing smaller than this is meaningless (the smallest length being the Planck’s length). Similarly, the no-tion of what lies between these ‘atoms’ of space is meaningless since it is only inside these atoms that the idea of ‘in between’ (which really requires the concept of distance) is defined. Thus the very con-cepts of space-time are non-fundamental and are built from more basic structures, what are known as ‘spin networks’. Furthermore, elementary par-ticles themselves are considered to be a part of this spin-network and thus all that is known, be it force, fields, gravity or particles, everything is combined into a single framework of “quantum geometry”. This approach has some significant advantages and some drawbacks. One very big advantage is that of being background independent. Recall that we discussed how QM breaks down in the background space-time of GR. Even string theory assumes a background of flat space-time of SR. LQG, on the other hand, has no such problem from its very ba-sic framework as it needs no concept of space-time outside of the theory itself. All of that said, LQGis still in the process of development and has some serious issues that still need to be resolved.So there you go, now you have a glimpse of the extremely technical, sometimes mind numbingly complicated but all the while awe-inspiringly beautiful and most profoundly significant Road to TOE!

Article 19

CRANIAL ELECTROTHERAPY

FOR STIMULATING HUMAN BRAINBy:

Faisal Mahmood

Cranial Electro Stimulation (CES) is a most popular technique for electrically stimulat-ing the brain and has long been prescribed by

the doctors in USA for treatment of anxiety, de-pression and pain etc. CES is an electrical system that generates a minor current that flows through clips placed on the ear lobes[1]. Such kind of treat-ment is minorly also available in Pakistan but it is so expensive that common man can’t afford it. Lo-cally people prefer to take oral medicines to cure from depression, anxiety, sleeping-sickness, in-somnia, and similar diseases which lead to a series of side effects, instead of this CES devices can be used which produce rhythms that are accompanied

CES basically interacts with the impulses pro-duced by our brain (Cranial System) through ac-tive nerves in the body. It generates low voltage small pulses with a specified frequency. These pulses stimulate the performance and actions ex-ecuted by the brain. When placed on the earlobes the electrical output of CES device is a square wave with equal positive and negative duty cycles.

INTRODUCTION

by feelings of calmness, relaxation and increased mental focus.

BASIC PRINCIPLE OF OPERATION

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The waveform of this device shows a positive pulse followed by a negative pulse, one of the same dura-tion, and then a small pause completes the cycle. It makes a little current (in microamperes) to flow through the cranial system, which can stimulate the brain in slow but steady manner.

DESIGN OF SIMPLE AS POSSIBLE CES

A counter is used to achieve a desired waveform and a CMOS timer serves as its clock.Any two consecutive outputs of the counter show a posi-tive pulse followed by a negative one of the same dura-tion and then a pause. The frequency of the system can be varied

The terminals E1 and E2 as shown in the block diagram above are basically meant to be placed at the earlobes. CMOS timer is used in ASTABLE configuration to provide the clock frequency (at 50% duty cycle) of which can be adjusted by the following equations:

At this frequency the clock can be fed into the counter. Now to calculate the output frequency of the counter we divide this frequency by the num-ber of times the counter counts before resetting, let the number of counts be N then the frequency will be:

This shows that the output frequency of the counter can be adjusted by varying the C and R which are used to tune the CMOS timer and the number of counts of the counter. By varying the frequency it can be used to cure specific diseases e.g. 0.5Hz can be used to cure sleeping sickness which was tested by us.Any counter can basically have two parts one is the control circuitry and the other are the flip flops so the maximum frequency is specified in terms of their delays

It is to be noted that if we are using a counter in the form of a readymade chip and not designing one we can simply get its maximum counter frequency from its data sheet.

EXPERIMENTAL RESULTS

The output waveforms of the counter can be viewed on a very sensitive oscilloscope as the following two results show as per our requirement a negative pulse followed by a positive one and then a pause.

Figure 2: The output waveform of the counter showing positive and negative pulse and then a pause to show a frequency of 0.5Hz for curing sleeping sickness.

Figure 1: Block diagram of the designed CES.tp=Propagation Delay of One Flip Flop

tg=Propagation Delay for the Control Circuit of the

Counter

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In order to see the effects of the device on the hu-man brain we have done EEG on a specimen to see its results

Figure 3: EEG Pattern of Mr. A. Zia before Using CES Device

Figure 4: Shows the EEG pattern while using the device placed on the earlobes.

Figure 5: Showing three EEGs for Normal, Pain and CES treated Subject.

The two EEG patterns in figure 4 and 5 show that the number of maxima have increased by using the device on the earlobes i.e. change in EEG pat-tern simply by applying current in microamperes which shows the effect of the device. The graphical figures show EEG experimental re-sults and proves the effectiveness of CES, it can be easily seen that the curve for normal subject is very much close to that of a CES subject in pain-ful condition, thus proving the effectiveness of the device for the cure of pain.

BRINGING DARK SECRETS TO LIGHT:What if dark forces of nature don’t exist?

the dark unknownsDark energy and dark matter could have been the stuff of cult physics and astronomy if so many eminent scientists of recent times had be-lieved in them, or attempted to prove their exis-tent (or absence). As things are however, there is a growing race to prove or disprove the two dark secrets of nature. Either ways, it could have a marvelously massive effect on what we know of astrophysics and celestial mechanics.

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Dark matter is hypothetical matter that is undetectable by its emitted radiation, but whose presence can be inferred from

gravitational effects on visible matter. On the other hand, dark energy is a repulsive form of energy that permeates all of space and tends to increase the rate of expansion of the universe. Both concept are very alike in that they are both unproved, both were involved to explain some parameters of the universe that cannot be ex-

plained otherwise and both are extremely elusive.

dark matterDark matter was used to explain the ‘missing mass’ of the universe. The properties of rotational speeds of galaxies, orbital clusters and the so-called gravi-tational lensing of heavy bodies (that bends light) seemed to point to large amounts of mass in many cases. Problem was, there was none to be seen by any kinds of telescopes or probing devices. Worse, there was no matter that could be observed by any kinds of present technology. The solution was simple: infer the presence of some very lightweight particles, but ones that were present in huge numbers multiply them together and you could explain a large mass, as well as the fact that we cannot detect them (very lightweight particles cannot be easily detected. And the par-ticles that have weights many times less than an electron are a nightmare to observe).

dark energyDark energy is only slightly less oblique. Of the many ‘models’ of the universe, the best known and provable one shows that the universe is expanding. And it is not only expanding, experimental evidence shows that the universe is expanding at an accel-erating rate. This, of course, is a bit of a problem because gravity dictates that matter be attracted to each other – meaning that the universe should by now be pulling itself in to each other. According to Einstein’s work, the speed at which the universe is expanding following the big bang should be slower than it actually is. This unexplained anomaly threat-ened to turn the whole theory upside down.Dark energy was introduced to solve this problem: definable as a kind of unknown energy that counter-acts the effects of gravity.But these concepts have been around since a long time: dark matter since 1933 and dark energy since 1998. And because so much effort has gone into proving their existence, some scientists are ques-tioning whether they really exist, or if we have not made some fundamental mistake when developing our laws of physics.The consequences, whichever way you take it, are enormous.

By: Muhammad Fahd WaseemBatch 17

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what if they existIf they exist, the question would be: why have we not been able to directly observe them? So far, all the observation and evidence that point to dark mat-ter and energy is completely indirect and/or circum-stantial. Yet, with a lot of money and resources hav-ing gone into building ‘dark detectors’, we have not caught one truly verifiable glimpse of them. The DAMA/NaI experiment and its successor DAMA/LIBRA have claimed to directly detect dark matter passing through the Earth, though most scientists remain skeptical since negative results of other experiments are (almost) incompatible with the DAMA results if dark matter consists of neu-tralinos (one of those lightweight particles talked about earlier). Dark energy, which is about three times more pervasive than dark matter, has been more elusive: scientists have not even claimed to have detected it yet.If they exist, it could solve a lot of problems would support the current laws of physics, no large scale modification of those laws would have to be made and it would open a vast source of nearly pure en-ergy that could, theoretically, be harvested for our use. On the other hand, there would be the realiza-tion that humankind is not really as intelligent as we

thought: after all, it would have taken us over 80 years to prove the existence of something we had already postulated – something that consists of over 90% of the mass-energy of the universe. Even more galling would be that the eminent scientists that are now calling for the scrapping of ‘dark’ ideas would have been wrong – science can hardly

afford to be wrong for so long.

what if they don’t existIt is only very recently since scientists have mount-ed a serious challenge against dark energy, saying there are new calculations that allow the laws of gravity and physics to be reconciled without in-troducing dark energy. The downside is that these calculations threaten a lot more the laws of physics and accepted universal models.Dark matter is less prone to such altercations, with almost all scientists believing in its exis-tence. Nevertheless, some compelling science has been put forward by some to prove oth-erwise. The downside is the same as before: wholesale changes made to all existing laws.Both of these altercations have resulted from a consistently fruitless effort at direct

The Crab Nebulais a supernova remnant and pul-sar wind nebula in the constel-lation of Taurus. The Nebula was observed by John Bevis in 1731; it corresponds to a bright supernova recorded by Chinese and Arab as-tronomers in 1054.

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detection, and most recently, some indirect evi-dence of non-existence.However, if dark energy is vanquished by these recent observations, cosmologists will have to rethink the perplexing universe they’ve grown to know and love.And it will not end there: one breakdown here and a domino effect could break down some of the most respected and fundamental theories of all time and space – Einstein’s general relativity theories and many postulates of the quantum physics. In other words, there exists a real danger of astrophysical laws ending back where they started: with the ar-chaic Johannes Kepler.Scientists are pretty reluctant to do that, for ob-vious reasons. But if the non-existence is finally

proved (of either dark energy and matter), it will re-veal possibly the largest red-herring of all science – the Large Hadron Collider built at CERN, Switzer-land. The LHC was built to detect the Higgs boson, which is a direct prediction of the very theories that the non-existence of dark energy and dark matter will break down. In other words, the Large Hadron Collider could be the most useless, and at a price tag of nearly 4 billion euros, the most expensive science

project of all time.

do they really existScientists wish they really knew for sure.

Evolution of Universe - Timeline

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Dr. Samar MubarakmandKindly tell us something about your early educa-tion and childhood in Lahore.I went to the Convent of Sacred Heart School which is a convent school primarily for girls but boys study there up to second kindergarten. Then I went for further schooling to Saint Anthony’s. I did my matric from there in 1956. After my matricu-lation I went to Government College Lahore from where I did my Masters. Lahore as you know was a border town and partition had taken place. Actu-ally my initial memories are of the Second World War coming to a close, partition had not taken place then and the struggle for a separate homeland for the Muslims was going on . I was 3-4 year old so I am conscious of those days. I was aware of the bombs exploding at Hiroshima and Nagasaki be-cause I saw the pictures in a newspaper and my father told us about it. The surplus stores of the

army of the British soldiers were on sale in La-hore like parachutes, small tins containing lunch packs for the troops etc. We used to buy them and play with them. In that lunch box I always en-joyed taking the chocolates out as nothing else was of much use to me. In the early days there were ri-ots in Lahore. I still remember parts of the old city in flames and smoke was visible from our house. We were living on the outskirts and from there we could see the walled city, even the flames and the smoke rising. So these are the early memories of the town where I was brought up and had my early education.

Sir, how did you go on from that to Oxford? I was always encouraged by my parents to take up science as a subject. When I was in Government College doing my research for Masters in Physics,

Interview

“Always remember, this soil contributed to your existence, and to your success at large.”

with

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the head of department of nuclear physics labora-tories in Oxford University came to Lahore on a visit and he visited Government College. He saw the equipment which I had built myself and the ex-periment that I was doing as a requirement for my M. Sc. thesis. After few months I qualified for my M. Sc. and joined the Atomic Energy Commis-sion. I worked for about 8 or 9 months and then the time came for most of us who were in the Atomic Energy Commission, as fresh Officers, to go abroad for higher studies. At that time I ap-plied for admission at Oxford University because it was a premier institution in those days. When my

in the 50’s and that is a manifestation of the peaceful applications of the nuclear energy. However since I was impressed by the event, in school I chose sci-ence. When I joined college I went for science again opting engineering out deliberately although I had a very high percentage of marks in FSC to qualify for admission. It was a very deliberate attempt to go for physics all the way. My father was the driving force and he said that we will one day need nuclear science and technology for the defense of the coun-try as well as for the advancement of social life in Pakistan.

Why did Pakistan opt for a nuclear route in spite of a weak economy? When we talk about the defense of a country we have to keep in mind the resources of the country: how much money it can afford to spend, what is the threat perception in the region, where are the threats expected from & the quantum of the threats?

Professor at Government College Lahore wrote to the Professor at Oxford, he immediately remem-bered his visit to Lahore and the work he had seen that I was doing and he offered me admission in the university. This is how I went to Oxford.

Were the early memories of Hiroshima and Naga-saki an inspiration to get into the nuclear physics field? It was awesome. It was impressive in a rather sordid way. You can’t even see a nucleus it’s so small and yet its power is so great it can destroy hundreds of thousands of lives and whole cities. The nuclear re-actors had not yet come in at that time. The first appli-cation of nuclear energy was uncontrolled form of devastation. The reactors came into being

At five years

At 14 years, F.Sc.

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Pakistan is a much smaller nation than its adversary across the border that has 8 times larger popula-tion, resources, defense expenditure & military hardware, resulting in a great imbalance. This im-balance was addressed by adopting a nuclear route. In Pakistan we chose nuclear deterrence simply be-cause it was the cheaper and most effective route towards a credible defense. When you have nuclear defense you don’t match numbers with numbers. On the other side of the border for example if they have 10,000 warheads it’s not relevant to us. If we have 50 or 100 warheads that may be just sufficient to destroy the other country. So when you have nu-clear deterrence in your scheme of things you go for limited expenditure on defense. It is not required to spend money beyond the minimum requirement.

When did the Nuclear Program Start? We didn’t go for nuclear technology just for the sake of it. In 1974 after the Indian Nuclear detona-tion, we had to launch our nuclear program. When India detonated the Bomb again in 1998 we had no choice but to respond. It should be realized that Pakistan was forced into a nuclear weapon program through the belligerence of its neighbors .There was a need for Pakistan to survive with dignity in the sub-continent.

British media has repeatedly said that there is a threat to the nuclear assets of Pakistan. Kindly elaborate something on the command and control of the nuclear assets?We have without doubt the best command and control system in the world. There is no way our nuclear weapons can fall into wrong hands. You can’t trigger a nuclear weapon unless you have the secret codes of the weapon. Weapons are all un-armed. All security measures as per international standards are in place. Media all over the world keeps writing about the command and control of nuclear weapons and the possibility of their fall-ing in the hands of terrorists. I would say this is sensational journalism.

What are the centers of excellences? How have they contributed to the defense of Paki-stan?A center of excellence is like a science city, a huge complex. Once you go inside it’s a very serene at-mosphere, lush green lawns and quietly scientists

At Oxford in the dormitory

At M.Sc Govt. College Lahore,1962

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are working. Recreational facilities are available such as gymnasium where people can go at the end of the day and relax. We have tried to create a first class international research establishment. This is the brain center of the NESCOM . Research done at the Centres of Excellence is regularly presented at the important international conferences dispel-ling the impression that we are living on borrowed technologies.

Sir, is nuclear proliferation really an issue on ground or is it just political?In the nuclear race, it was always about who made the first bomb? It was a Ger-man scientist almost at the end of Sec-ond World War who achieved the break-through in the application of atomic energy for destructive purposes. These German scientists were taken away to US and worked at Princeton and there-fore the first nuclear bomb appeared on the scene in America. Later on we saw nuclear weaponry spreading to Eng-land, France, and Russia and later on we heard about Israel and South Africa, then India and Pakistan. How did this entire technology spread? It spread to some areas through proper means e.g. the western powers were given nuclear technology willingly by scientists of the western origin who were working in the US. The technology was denied to India, Pakistan, China and Russia because these were people of a different race and creed. The Russian took away some scientists from America and these scientists helped Russians build the atomic bomb. They were called the Rosenberg’s. The Rosen-berg couple were caught and put on the electric chair in America for this crime. Then later on the Chinese developed the bomb. A Muslim nation always works in isolation. It can only be helped by another Muslim nation. Since we were the first Muslim nation to develop the nuclear technology; we weren’t helped by any other Muslim nation.

What is the role of Metallurgists in Modern tech-nology?Their role is peaceful as well as in weapons tech-nology. We need to produce metals like uranium, calcium, magnesium and zirconium which are used in nuclear power plants which are used to generate electricity. We need to totally master the technology of extracting these metals. You cast those metals, mould them into different shapes and heat them to give them extra strength.

What is your vision about the GIKI?GIKI gives very high quality education and has very good facilities for students. The students that GIKI produces are really the very best that we have seen in physical science, electronics and metallurgy. We have always used GIKI students to enter the nuclear program and missile program. Your difficulty is that your campus was conceived with certain thoughts in mind that it should be in a remote area; it should be in frontier province.

After the award of D. Phil. at Oxford

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It is a very ideal thing to say that you have a campus far away from everywhere, let the students sit there and think day and night about research and win a Nobel Prize. But it doesn’t happen like that and it is not a realistic thought. But you can’t grow beyond certain limits because of this very impediment. I was instrumental in convincing the President and Prime Minster to give you more hostels and two new hostels were built.

Does this mean GIKI is doomed?No it is not doomed, but it will not make progress beyond what it already has. To exceed the present limits you need more funds and lots of funds.

But in any case, GIKI has a flat No from govern-ment?No, it is not a flat “No”, the rules of business don’t allow us to give money to GIKI. If government gives money to your university then why it should

not give money to all the other private universities.

Any messages for the youth of Pakistan?First of all the youth should feel very proud of their country. Secondly, Pakistan has been created in the name of Islam. We expect that we will work for the betterment of the country and then God will ensure our security and prosperity.

If this is really Pakistan, this is like a courtyard of a mosque. If you believe that you are sitting in the courtyard of a mosque, you will never do anything wrong. Everyone, who has done good work for Paki-stan has risen in stature. If you continue on this thought process, you will succeed. Money is not everything. Money is important but money is not all. Inner sat-isfaction is all.

Specific message for GIKI students.Giki students are doing very well, keep on doing so.Wherever you are, whether serving here or abroad keep in mind you are Pakistanis so you must work for your country.Send money to charitable institutions, facilitate your colleagues, do it at any level, micro or macro.

After the highest National Award, Nishan-e-Imtiaz,2003

After the Atomic Tests at Chaghi with the Prime Minister

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By: Foaad Ahmad Tahir

Energy continues to play an important role in our lives and in economy of the world. We require input of energy at every stage from

cradle to grave of various products and processes. However our sources of energy, primarily fossil fu-els, and their rate of use are unsustainable. In such a scenario renewable sources of energy, particularly wind energy, presents with a sustainable solution. This paper explores the design optimisation of mi-cro wind turbines for domestic use. This optimisa-tion is done by synchronisation of mechanical and electrical systems. This is achieved by using multi speed gearbox and turbine loading mechanisms to ensure synchronous operation of the generator, thereby eliminating the need for fully rated power electronic converters. An energy storage system is also included with the wind turbines. This serves to not only smooth out the supply of energy in off grid systems, but also acts as a backup in areas where the grid is not strong and power outages are norm due to gap between supply and demand of electricity generation.

standards has increased the per capita energy con-sumption. This need for energy can broadly be cat-egorized into three domains; electricity, transporta-tion and domestic heating. Electricity consumption accounts for nearly 1/3 of all energy needs. Electric-ity represents the most clean and convenient source of energy, having uses as diverse as lighting, heat-ing, electronics as well as transport. World electric-ity consumption in 2006 was 19,014 TWh 1 and its breakdown is presented in the table 1 above. As can be seen, the major share of electricity production is fossil fuel based. The variation in electricity fuel mix from 1971-2004 is shown in figure 1.

Figure 1: Electricity Fuel Mix (1971-2004) 2

Table 1:Electricity Generation by Fuel

Keywords – sustainability, wind turbine, energy storage

Introduction: World energy consumption has experienced a steady increase in the 20th century. A population boom supported by a similar improvement in lifestyle

MICRO WIND TURBINES:SUSTAINABLE SOLUTION FOR MEETING ENERGY CRISIS

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Figure 2: Sources of Global CO2 Emissions, 1970–2004 3

Sustainable Development :According to the definition in the Brundtland Re-port:“Sustainable development is development that meets the needs of the present without compromis-ing the ability of future generations to meet their own needs.”Sustainability issues regarding current energy con-sumption are:1. Over reliance on fossil fuels, a non renewable source of energy

Figure 3: Range of Total Greenhouse Gas Emissions from Electricity Production Chains 4

2. Emission of pollutants, mainly greenhouse gas CO2, at a rate which is faster than the ability of environmental sinks to absorb.

Environmental Footprint:The environmental carbon footprint of various electricity generating technologies is shown in figure 3. These include the direct stack emissions from fossil fuels as well as the emissions from chain steps in a whole systems context. As can be seen coal is the dirtiest form of electricity generat-ing technology. Renewable energy is the cleanest source of electricity as they have no stack emis-sions and only embody energy of manufacturing. Wind energy has the lowest emissions.

Renewable Energy:As was seen in figure 3, renewable energy rep-resents the cleanest source of energy generation. It has no direct CO2 emissions and the embodied energy of construction is readily dropping with the advancement of technology. This is constant-ly reducing its price and making it economically competitive with fossil fuels. This has resulted in significant investments in these technologies in the past few years, as is shown in figure 4.

Figure 4: Selected Indicators for Several Renewable Energy Schemes for 2006 – 08 5

Salient Features of Wind Industry: 6

The wind industry has witnessed a remarkable boom in the past 15 years. This is currently the most mature technology and its cost of electric-ity generation is comparable with fossil fuels in many places. It also represents the majority of the new renewable energy installations. Some of its salients features include:

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Micro Wind Turbine Systems:Micro wind turbines represent the 1-10 kW range of turbines. These are mainly used for domestic purposes. The different components of a typical wind turbine are shown in figure 5. Based upon the mechanics of turbine blades and the workings of electric generator, following are the main features of such turbines:• High dependence on mean wind speed• Maximum stress at root of blade• Best performance at fixed tip speed ratio (6-8), variable RPM• Use of induction or permanent magnet electric generator These features make synchronous generation from wind turbines a particular problem. This problem can be solved in two ways. The preferred electron-ic solution is to have the synchro-

Figure 7: Blade Profile

Figure 6: Graph of Tip Speed Ratio vs. Cp

Figure 8: Streamlines Across Blade Element

nous generator run at variable speed and fully rated power electronic controllers are used to link them to the grid. These controllers consist of a converter and an inverter connected by a constant voltage DC link. The other mechanical solution is to use a multi speed gearbox and turbine loading control to man-age the tip speed ratio in a manner to keep the gen-erator running at fixed speed.

Performance Indicators:The major performance indicator of a wind turbine is the variation of its coefficient of power vs the tip speed ratio. Other design parameters include the blade profile. Both of these influence the effective streamlines across the blades. These are illustrated in figure 6, 7 and 8 respectively.

Figure 5: Wind Turbine Components

• Energy generation in 2008 - 260 TWh • Average growth rate for last 10 years - 28%• Share in new electricity generating capacity built in the EU last year – 43%

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Energy Storage: Intermittent generation of electricity from wind tur-bines requires an energy storage system for off grid systems as well as a backup in places where the grid is weak and power outages occur frequently. There are two preferred mechanisms for the storage of this surplus energy. They are

I. Electrochemical Battery Batteries present a simple system to store the en-ergy and requires minimum maintenance. However it is very sensitive to temperature surges and rapid charge/discharge.

II. Mechanical Flywheel Mechanical flywheel storage systems are relatively

Figure 9: Mechanical Flywheel Schematic Figure 10: Comparison of Energy Storage Systems

in the industry. They represent a robust system with considerably longer lifetimes, higher ef-ficiencies (90%) and high power density. They however have the inherent complexity of flywheel - electric motor coupling transmission.

Conclusion:Energy continues to play an important role in our societies. Conventional fossil fuel resources are finite and becoming harder to produce as existing stocks are depleted. Renewable energy technology is advancing at an accelerating pace and presents great hope for the future. Wind energy is playing the leading role and holds greatest promise as the leading source of energy generation in coming years.

References:1. http://www.iea.org/Textbase/stats/electricitydata.asp?COUNTRY_CODE=292. http://www.thepresidency.gov.za/learning/reference/factbook/05-01-04-G01.htm3. http://www.ipcc.ch/pdf/assessment-report/ar4/wg3/ar4-wg3-chapter1.pdf4. http://www.iaea.org/Publications/Magazines/Bulletin/Bull422/article4.pdf5. http://www.ren21.net/pdf/RE_GSR_2009_update.pdf6. http://www.gwec.net/index.php?id=97

36 News

Science Worldthe latest scientific news from around the globe

A view of large superconducting magnets at LHC

On 30th March 2010, LHC broke its own record set on 30th November 2009 by colliding particles at an energy of 2.36 TeV, this time by smashing the beams at an energy of 7 TeV. Previously, the record for highest energy man-made particle col-lisions was held by Fermilab’s Tevatron collider at 1.96 TeV.

Marking the 400th anniversary of the first use of an astronomi-cal telescope by Galileo Galilei, 2009 was declared the Interna-tional Year of Astronomy by In-ternational Astronomical Union (IAU) and UNESCO, with the aim to “stimulate worldwide inter-est, especially among young people, in astronomy and sci-ence. IAU planned and com-

pleted twelve major global projects including one hundred hours of online webcast lectures to light pollution cleanup projects to mass usage of astronomical telescopes throughout the world, viewing what Galileo saw from street sides. In addition, national and special projects were com-pleted, all regarding promotion of astronomical studies in the general public.

Deposits of at least 600 metric tons of water-ice have been confirmed on the moon’s north pole as a result of search by NASA’s mini SAR (synthetic aperture radar) aboard India’s Chandrayaan-1 spacecraft. The radar found more than 40 small craters, ranging from 2 to 15 kilometers in diam-eter, containing water-ice. Before this, in Sep-tember of 2009 NASA confirmed the existence of water on moon using data from its Deep Impact spacecraft and Chandrayaan-1, India’s first mis-sion to moon. Later, in October, NASA’s Lunar Cra-ter Observation and Sensing Satellite (LCROSS) found clear evidence of water on the south-pole of the moon, specifically in the crater Cabeus.

Skip Garibaldi of the Emroy University and Jacques Distler of the University of Texas have published a paper rebutting Garrett Lisi’s groundbreaking claims, published in his famous paper, “An Excep-tionally Simple Theory of Everything” (AESToE). In November 2007, in what is now considered to be the most downloaded paper on the internet, Garrett Lisi tincorporated the whole framework of particle physics in an elegant yet complicat-ed mathematical structure called the E8 group and combined it with gravity to give us what seemed to be a complete theory of everything.

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A geometrical representation of the E8 group with different shapes and colours representing different elementary par-ticles. Taken from LIsi’s famous AESToE paper.

Garibaldi and Distler claim to have proved that any such class of models cannot possibly be ac-curately integrated into the E8 group. Their paper is soon to be published in the journal Communi-cations in Mathematical Physics

Dr. Grigoriy Perelman, in a dumb-founding move, turned down the prize money for having solved one of the Millennium Prize Problems. Millenni-um Problems was a collection of seven unsolved mathematical problems, six of which remain un-solved, for which CIM has offered to award one million dollars to any person who solves any one of them. After solving one of them in 2002, a prob-lem whose solution had eluded mathematicians for nearly a century, the Poincare Conjecture, Perelman showing extremely reclusive behavior cutoff all his connections with the mathematical community. He peaked his fame after refusing to accept the Field’s Medal, an equivalent of the No-bel Prize for mathematics, for his contributions. Then again recently, after withstanding years of scrutiny by mathematical community all over the world, when CIM awarded him the prize money on 18th March 2010, Perelman turned it down.

Dr. Grigoriy Perelman

Fossils 4.4 million years old, of a female hominid, shed new light on the evolution of homosapiens. Nicknamed Ardi, after her technical name Ardipithecus ramidus, she lived almost a million years before the famous Lucy, or Australopithecus, whose fos-sils were found in 1974, close to a site where Ardi was re-covered. Skeletal features in-dicate an unusual mixture of two and four legged pattern of walking, one for ground and one for trees respective-ly, much less like chimpan-zees than evolutionary bi-ologist would have thought. Its physical features indicate ominvory, man-like mating style and other human-like behavior. Ardi also provides a much better look into the evolution of some of its previously found decendants, like Lucy. Scientists are calling it one of the most revealing hominid fossil they could have imagined.

World’s first complete quantum computer

Researchers at National Insti-tute of Standard and Technology, Colorado, USA, have developed the world first complete quan-

tum computer. What looks like an old computer chip is capable of performing quantum logic operations using two trapped ions acting as qubits, the analog of bits in a normal computer. This two qubit computer was able to perform 160 operations with an ac-curacy of 94%, a significant improvement, though still lacking the standard of 99.99% performance required for its large-scale implementation.

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0 Smaller Beta Decay Rates of Iron Isotopes for Supernova Physics

Dr. Jameel-Un-Nabi

to generate an explosion. The Chandrasekhar mass of the core is proportional to Ψe

2 neglecting the pressure of the outer material. Each tenth of a solar mass of the iron core traversed by the shock costs around 1.7 x 1051 ergs to dissoci-ate 56Fe into its constituent nucleons and if the iron core is too massive the shock will lose energy to fi-nally become stalled. A shock revival mechanism is then in order. A smaller precollapse iron core mass and a lower entropy should favor an explosion.The isotopes of iron, 54,55,56Fe, are mainly respon-sible for decreasing the electron-to-baryon ratio during the oxygen and silicon burning phases of massive stars through electron capture and positron decay processes. The beta decay rates for these iso-topes of iron bear consequences for the presuper-nova evolution of massive stars (see e.g. [2]). The beta decay rates of 54,55,56Fe were calculated on an extended grid of temperature-density scale using the pn-QRPA model [3, 4] in this work.The isotopes of iron, 54,55,56Fe, are mainly respon-sible for decreasing the electron-to-baryon ratio during the oxygen and silicon burning phases of massive stars through electron capture and positron decay processes. The beta decay rates for these iso-topes of iron bear consequences for the presupernova

Faculty of Engineering Sciences, GIK Institute of Engineering Sciences and Technology.

Abstract: During the late phases of stellar evolution beta decay on iron isotopes, in the core of massive stars, plays a crucial role in the dynamics of core-collapse. The beta decay contributes in maintaining a ‘respectable’ lepton-to-baryon ratio (Ψe) of the core prior to collapse which results in a larger shock energy to power the explosion. It is indeed a fine tuning of the parameter Ψe at various stages of supernova physics which can lead to a successful transformation of the collapse into an explosion. The calculation of smaller beta decay rates presented here might help in fine-tuning of Ψe for the collapse simulators of massive stars.

Core-collapse simulators world-wide find it challenging to convert the collapse of an iron core of a massive star into a successful

explosion. All that we know concretely is that the core of a massive star implodes in a period of 0.5 - 1 s, the released energy is ~ 1053 ergs of which about 1% is transferred by neutrinos to eject the envelope of the star to cause the supernova explosion (veject ≈ 104 km/s) leaving behind a neutron star with a mass ≈ 1.4 solar masses. Modeling a 1% effect is indeed a challenging task for the theorists who are constantly incorporating more reliable microphysics into their simulations to achieve a successful explosion. For a review of evolution and explosion mechanism of massive stars see e.g. [1]. Weak interaction process-es, including beta decays and electron capture, not only reduce the entropy of the core but also alter the star’s Ψe. Due to these weak interactions the value of Ψe for a massive star changes from 1 (during hy-drogen burning) to roughly 0.5 (at the beginning of carbon burning) and finally to around 0.42 just be-fore the collapse resulting in a supernova explosion. The temporal variation of Ψe within the core of a massive star has a pivotal role to play in the stel-lar evolution and a fine-tuning of this parameter at various stages of presupernova evolution is the key

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FIGURE 1. Comparison of the decay rates calculations using the pn-QRPA model (left panel), shell model (middle panel) and the FFN calculations {right panel) for 54Fe. The abscissa represents the log of beta decay rates in s-1 whereas the or-dinate denotes the stellar temperatures in units of 109K. The insets in legends give the log of stellar density in units of gcm3

evolution of massive stars (see e.g. [2]). The beta decay rates of 54,55,56Fe were calculated on an ex-tended grid of temperature-density scale using the pn-QRPA model [3, 4] in this work. The beta decay rates of 55Fe are important during the silicon burning stages of massive stars. During this phase of stellar evolution beta decay of 55Fe leads to a crucial increment in the Ψe values. Fig. 2 shows the comparison of beta decays of 55Fe as a function of stellar temperatures and densities. This time the comparison of the reported rates with shell model is relatively better at lower densities. How-ever the shell model rates are still bigger. At higher densities the shell model rates are up to 5 orders of magnitude bigger. FFN rates are up to 4 orders of magnitude bigger than the pn-QRPA rates for rea-sons mentioned above. Fig.3 finally depicts the comparison of the three calculations for the case of 56Fe. Here the re-ported rates are again reduced as compared to FFN and shell model results. The comparison with shell model and FFN improves at high temperatures and densities. One again notes that the calculated decay rates are 2-4 orders of magnitude reduced as com-pared to earlier calculations.

FIGURE 2. Same as Figure 1 but for 55Fe.

FIGURE 3. Same as Figure 1 but for 56Fe.

Further FFN did not take into effect the process of particle emission from excited states and their parent excitation energies extended well beyond the particle decay channel. These high lying ex-cited states began to show their cumulative effect at high temperatures and densities. The main finding of this work includes that the beta decay rates on 54,55,56Fe are around 2-4 orders of magnitude smaller than previously assumed. What may be the consequences of reported weak rates of iron isotopes for core-collapse physics? The reduced beta decay rates will offer less resis-tance in decreasing the Ψe value through electron capture reactions during the late phases of stellar evolution. The pn-QRPA calculated weak rates may favor a smaller precollapse iron core mass and a lower entropy than previously assumed. The reported microscopic calculation of decay rates may assist the collapse simulators in fine-tuning of the Ψe value of the cores of massive stars dur-ing late phases of presupernova evolution for a positive outcome. Collapse simulators should take of this work and employ the pn-QRPA calculated weak rates in the simulation codes to check for some interesting outcomes.

REFERENCES1. S. E. Woosley, A. Heger and T. A. Weaver, Rev. Mod. Phys. 74, 1015 (2002).2. A. Heger et al. Astrophys. J. 560, 307 (2001). 3. J.-U. Nabi and H. V. Klapdor-Kleingrothaus, Atomic Data and Nuclear Data Tables 88, 237 (2004).4. J.-U. Nabi and H. V. Klapdor-Kleingrothaus, Atomic Data and Nuclear Data Tables 71, 149 (1999).5. K. Langanke, G. Martinez-Pinedo, Nucl. Phys A673, 481 (2000).6. G. M. Fuller, W. A. Fowler and M. J. Newman, Astrophys. J. Suppl. 42, 447 (1980); 48, 279 (1982); Astrophys. J. 252, 715 (1982); 293, 1 (1985).*This work was presented in the Third International Meeting on Frontiers of Physics, IMFP, Kuala Lumpur, Malaysia, 2009.

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040 Research Paper

Imaging Capability of PHEMT, AlGaN/GaN and Si Micro Hall Probes for Scanning Hall Probe Microscopy between 25-125oC

Dr. R. Akram1, Dr. M. Dede2, and Dr. A. Oral3

1Faculty of Engineering Sciences, Ghulam Ishaq Khan Institute of Engineering Sciences and Technology2Nanomagnetics Instruments Ltd. UK.

3Faculty of Engineering and Natural Sciences, Sabancı University, Turkey

We present a comparative study on imaging capabilities of three different micro (1μm x 1μm) Hall probe sensors fabricated from narrow and wide band gap semiconductors for scanning Hall probe microscopy (SHPM) at vari-able temperatures. A novel method of Quartz tuning fork AFM feedback has been used which provides extremely simple operation in atmospheric pressures, high-vacuum and variable-temperature environments and enables very high magnetic and reasonable topographic resolution to be achieved simultaneously of micro and nano magnetic structures and domains.

THE growing interest in the investigation of localized surface magnetic field fluctuation at variable temperatures, with high spatial resolution and for non metallic samples, has made the scanning Hall probe microscopy (SHPM) with

quartz tuning fork AFM feedback technique to be the one of the best choice as it provide means to perform sensitive, noninvasive, and quantitative imaging capabilities. SHPM technique offers various advantages and complements the other magnetic imaging methods like Scanning SQUID Microscopy (SSM) [2], Magnetic Force Microscopy (MFM) [3], Mag-netic Near Field Scanning Optical Microscopy [4] and Kerr Microscopy [5]. However, there have been few reports [6, 7] on magnetic imaging with Hall sensors at high temperatures. In general two dimensional electron gas (2DEG) materials with high band gap (greater than 2.5eV), like AlGaN/GaN, of-fer the advantage of being physical hard and it helps in reducing the possibility of thermally induced intrinsic conduction and existence of a high mobility of a two dimensional electron gas layer which greatly enhances the magnetic sensitivity of Hall sensors. On the other hand 2DEG material with low band gap, like PHEMT, offers high response level and thus helps in increasing the sensitivity of the system. A SOI structure, which provides CMOS compatibility have also been investigated for their application in Hall Effect sensors.

I. DEVICE CHARACTERIZATION: Micro Hall probes with effective dimension of 1μm x 1μm have been fabricated using optical lithography in a class 100 clean room environment from all three types of materials. Device fabrication process consists of three major steps which are: 1) formation of the mesa and active “cross” patterns by reactive ion etch-ing (RIE); (2) thermal evaporation of Ohmic contacts; and (3) rapid thermal processing (RTP) in a nitrogen atmosphere (4) Wire bonding using ultrasonic wire bonder. The layer configuration of fabricated Hall probes are shown in Fig. 1. Hall Sensors have been characterized based on their elec-trical characteristics (Hall voltage (VH) vs. Hall cur-rent (IH)) and magnetic (Hall Coefficient (RH) vs. Hall current (IH)) characteristics up to bias temperatures from 25oC to 125oC. As shown in Fig. 2. A linear rela-tion can be observed between VH vs. IH characteris-tics, with two different dynamic resistances (slope of VH vs. IH curve, rH Δ (VH / IH) regimes. These regimes are low current regime (IH ≤ 100μA) and high current regime (IH > 100μA). The similar behavior can be observed in magnetic characteristics. It is speculated that this decrease in the rH value is due to the fact that there might be an opening of a new conduction channels by applying high current causing an increase in the number of par-allel paths. This argument can be supported by using the above mentioned temperature dependent comparison.Based on these results we can say that PHEMT probes, which show a highest degradation in the signal level, are the worse choice to be used for high temperature SHPM applications. We have also investigated the run time (effect of high tem-perature exposure time) effect on electrical and magnetic characteristics under high temperature environments. The results showed no significant change in the values in case of GaN, while a decrease of signal level has been observed for the other two types of probes, suggesting a safe use of GaN Hall probes in scanning systems over a long time in harsh conditions.

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II. SCANNING HALL PROBE MICROSCOPY: A commercial Low Temperature-SHPM system from Nanomagnetics Instruments Ltd.[9] with some modifications for high temperature operations is used to perform the scanning experiments. This scanning Hall probe microscope can operate under two different feedback schemes namely, STM and AFM. In this a novel method of quartz tuning fork AFM feedback has been implemented. A 32.768 kHz Quartz crystals tuning forks with stiffness of 29 kN/m has been used for AFM feedback. Fig. 4 shows the assembly of Hall probe on a Quartz tuning fork [10]. In order to investigate the high temperature operation of these micro Hall probes, a low noise heater stage has been embedded in the LT system.The Hall sensor is positioned 12µm away from corner of a deep etch mesa, which serves as a crude AFM tip. As the combined assembly of a sensor and tuning fork approaches the surface of the sample, due to tip sample forces the resonant frequency of the Quartz tuning fork shifts. The frequency shift ∆f, measured by the PLL circuit is used for AFM feedback to keep the sen-sor sample separation constant with the feedback loop. This way reasonably good quality AFM topography is also recorded together with magnetic scan. In order to compare the ultimate performance of these three different types of Hall probes we have imaged magnetic bits of the Hard Disk at various temperatures. The results of magnetic imaging of Hard Disk sample obtained in AFM track-ing mode at 25oC to 125oC with a scanning speed of 5µm/s and scan area of 50µm x 50µm resolution of 256 x 256 pixel shown in Fig. 4.III. CONCLUSION: The study of electrical and magnetic characteristics shows that GaN HP is a best choice for an ap-plication in high temperature SHPM system compared to other two types. The confirmatory SHPM results of a hard disk sample for temperature range of 25oC to 125oC has been presented to show that out of these three probes GaN micro Hall probes are better for high temperature ranges but comparison of the images makes PHEMTs to be good choice at room temperature. While on the other hand due to complex structure of PHEMT and AlGaN/GaN 2DEG structures, it makes Si to be considerable choice due to its relative good imaging capability and CMOS compatibility to be used for room temperature and batch processing applications.

ACKNOWLEDGMENTThis work is supported in Turkey by TÜBİTAK, Project Numbers: TBAG-(105T473), TBAG-(105T224).

REFERENCES[1] A.Sandhu, et al., J. J. Appl. Phys. vol. 43, pp. 777-778, 2004.[2] Kirtley JR, Annual Review of Materials Science vol. 29, pp. 117-148, 1999.[3] Y. Martin and H.K. Wickramasinghe, Appl. Phys. Lett., vol. 50, pp. 1455-1457, 1987.[4] E. Betzig, et al., Appl. Phys. Lett. vol. 61, pp. 142-145, 1992.[5] F. Schmidt and A. Hubert, J. Mag. Magn. Mat. vol. 61, pp. 307-320, 1986.[6] Z. Primadani, H. Osawa, A. Sandhu, Journal of Applied Physics vol. 101, pp. 09K105-09K105-3, 2007.[7] T. Yamamura, et al., Journal of Applied Physics vol. 99, pp. 08B302-08B302-3, 2006.[8] P. Rajagopal, et al., Material Research Society Symposium Proceedings 743(3), 2003.[9] Low Temperature Scanning Hall Probe Microscope (LT-SHPM), NanoMagnetics Instruments Ltd. Oxford, U.K. [10] R.Akram, M. Dede, and A. Oral, IEEE Transactions on Magnetics, vol. 44, pp. 3255-3260, 2008.

FIG. 2. Effect of Temperature on the Hall Voltage vs. Hall cur-rent characteristics for all three types of micro Hall probes.

Fig. 4. SHPM image of hard disk sample at high temperatures. Scanning speed was 5µm/s.

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[S.W.A.T]m (Surface With A Touch)multi

The objective of this project was to build a Multi Touch Surface Computer using the phenomenon of FTIR (Frustrated total internal reflection). The in-spiration behind this project was Microsoft Surface which costs around $12000 (10 Lac Rs.). But the system that we have developed only costs $1250 (1 Lac Rs.). Due to its much low cost compared to Microsoft Surface, this project provides the touch surface to a common user and small business own-ers to showcase their business in a more interactive manner and interact with their computers in a more intuitive manner. We have also developed few applications to dem-onstrate the different industries where this product can be used.

Pictures and Play It: These two simple ap-plications demonstrate zoom, rotate or move multi-ple pictures or videos at the same time using natural human gestures.

Paint It: In this application user can use all his 10 fingers to draw on the screen and even can choose the color and thickness of the strokes. Multiple people can simultaneously draw on the screen using their fingers to create collaborative pictures.

Chemistry Magic: This application is to demonstrate the use of this product in education industry. You can drag different elements from the

bucket and place the required cat-alyst to get an animation of the reaction. For ex-ample you can drag two atoms of hydrogen and one atom of oxygen to visu-ally interactive animation of water which is more interesting than just read-ing the equa-tion in a book.

Piano: This application demonstrates the use of this product in musical industry. You can resize, rotate or move the piano according to your liking and then play the piano. There is no need to buy different pianos for different people anymore.

Ice Hockey: Multiplayer gaming is usually done using LAN but it is more fun to play with your friends when they are right in front of you. In this application you can play a game of ice hockey with as many players as you want.

Tracking Touch: It is a simple applica-tion which creates a circle wherever you touch the screen and it moves with your fingers. But this application actually shows us the power of the system to register more than 30 simultaneous touches at the same time. This number can be eas-ily increased by using more powerful processor and RAM.

Final Year Project, FCSE, GIKI

Project TeamAsfandyar Nasim Khan

Muhammad Zain ul Abidin Sarmad Ahsan Siddiqui

Yasir Naveed

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Robotic Arm Control Using Human Arm Movement

Irfan Khan, Samee Zeeshan Ali, Farhan Javed & Arafat Asghar

Applications: - Object handling at inaccessible places. - Hazardous material handling - Bomb diffusing - Interactive design using holography e.g. working on a scaled holographic image in a console box while robotic arm works on actual object. - Scaling the robotic arm to any size for instance the size of a crane and controlling it via console box.

The basic aim of this project is to design a Console Box (a rectangular coordinate System) using a matrix of IR range finders. In this Box the hand is considered to be a single point obstacle through which X, Y, Z coordinates are found.

The console box consists of twenty four IR range finders. Out of these twenty four sensors, four are mounted on the x-plane, fifteen are mounted on the y-plane and five are mounted on the z-plane. The IR range finders give a specific analog value at a certain distance from the object in its vicinity so the position of the hand gives a set of analog values which are then provided to the microcontroller (PIC 16F877-A) converting them into an 8-bit digital number for further calculations. Four microcontrollers are being used as slaves to get data from these 24 sensors. Each slave microcontroller then converts the voltage signal to corresponding distance via lookup tables. The resolution of the lookup table is 1cm. The master microcontroller receives the coordinates of the human arm from each slave using I2C protocol. It then uses these coordinates to compute angles of re-spective joints of the robotic arm using inverse kinematic equation. The master microcontroller then provides three PWM signals as input to the H-bridge circuitry which gives analog output voltage to drive the motors of robotic arm to a specified position.

Final Year Project, FEE, GIKI

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RADIANT MOTOR ENERGIZER

The technological and consequently social progress that we see around us today owes itself to proper and ef-ficient use of energy resources, but unfortunately conventional fuel reserves (fossil fuels) are dwindling at an alarming rate and have proved to be detrimental to the environment and the biosphere. So search for renew-able, sustainable, efficient, and clean energy sources has become one of the most hotly researched areas in the domains of science and engineering. One such promising area of research is the concept of “Radiant Energy”. This idea was first presented by Nikola by Nikola Tesla. The Radiant motor energizer is the brainchild of John Bedini an American scientist, engineer and entrepre-neur, theoretically this device can service both mechanical and electrical loads in an extremely efficient (High COP: Coefficient of Performance) and environmentally friendly manner. The scope of our project was to build and test a device that used ideas and concepts presented by Bedini and Tesla. Our device was designed and built using readily available and cheap components, it comprised mainly of coils of wire, transistors, magnets and some timing circuitry. The device was primarily used as a battery charger but it can also be used to service a light mechanical load. The results we obtained were promising but a lot more research and design is required before a commercially viable and hassle free system can be introduced for commercial/domestic use. The device is highly scalable (The device can be replicated on a micro, macro or large scale easily). Future applications of the device include:-Powering household loads.-Energy solutions for far flung areas that are off the grid.-Servicing of standalone devices operating in off grid regions.-Miniaturized versions can be used to power handheld devices.-Can provide environment friendly energy solution. This project would have been impossible without the encouragement and guidance of our advisor Dr Rizwan Akram, who actually proposed it as a Final Year Project for us.

DESIGN AND FABRICATION OF AN EXPERIMENTAL SETUP TO DEVELOP NUSSELT NUMBER CORRELATION FOR SINGLE PHASE

FLOW THROUGH PLATE HEAT EXCHANGERPlate heat exchangers are widely used in dairy, pharmaceuticals and paper industry as well as in HVAC ap-plications due to numerous advantages. A number of analytical and experimental studies have been conducted to study the heat transfer characteristics of tubular heat exchangers. However a very limited work is found in open literature regarding the heat transfer through plate heat exchangers. Thus the objective of this project is to design and develop an experimental setup to investigate the heat transfer characteristics and thermal per-formance of plate heat exchangers. An experimental setup has been designed in order to develop empirical correlations to estimate single phase heat transfer and pressure drop for plate heat exchangers with various commercially available chevron plates. This project also focuses on the design of various parameters in order to select the components of the setup. The apparatus thus designed and fabricated will be used to conduct single phase experiments using fluids at various flow rates and temperatures in order to develop correlations corresponding to a maximum Reynolds number (Re) of 2500 and Prandtl number (Pr) in the range of 6 to 25.

Ali Touseef, Atta ur RehmanHassan Shabbir Syed & Syed Burhan Haider

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About Science Society:The GIKI Science Society is one of the most ac-tive societies in Ghulam Ishaq Khan Institute of En-gineering Sciences and Technology. It has always played an important role in the extra curricular cul-ture of this place. Here is a brief detail of Science Society activities.

Science Marathon:Science Marathon is the biggest internal event or-ganized by GIKI Science Society. The purpose of this event is to show the lighter side of science. In this event teams are given some clues to reach a fi-nal place in the form of mathematical and physical problems. After solving these problems they reach at their final destination where they are given a practical problem. Team which completes all these stages first is declared the winner. The winners are given handsome cash prizes.

All Pakistan Science Fair:The All Pakistan Science Fair is an external event organized by the GIKI Science Society, and is by far its largest. Open primarily for colleges and uni-versities, it attracts institutes from across the Paki-stan to participate in this long running event. This gala features the prestigious All Pakistan Science competition in which participants compete for the coveted running trophy in a multitude of challenges designed to test their knowledge and understanding of the history, theory and practical applications of Science. Alongside the primary competition, there is also a Science Exhibition contest that showcases unique projects and concepts designed by students from all over Pakistan.

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Science Kasoty:This event comprises of two rounds. In the first round that is the qualification round MCQ’s based general knowledge test is given. In the final round teams have to guess the personality of a scientist, an event/invention/phenomena on the basis of the hints provided. There is also an other round called Dumb charade in which one team member has to act and the other two have to guess. The winner is awarded a trophy along with the certificates and cash prizes.

Science Eureka:The purpose of the Science Eureka is to challenge and enhance the experimental approach of the par-ticipants. This is a team based event where each team comprises of three students. Each team is giv-en a problem for which they have to design an ex-periment in which simplest approach and minimum apparatus is used. The winner is decided on the ba-sis of their approach towards the problem solving and the viva taken by the judges. The winners are awarded with certificates and cash prizes.

Astronomy Night:Astronomy night is the most interesting event or-ganized by GIKI Science Society. Telescopes are brought to GIKI to provide a chance to the students, who are interested in astronomy, to see various as-tronomical objects in space. Besides, interesting and informative lectures are also arranged on as-tronomy and space sciences which are delivered by renowned space scientists of the country. There is always a very active participation from the students at this event.

Scientific Magazine “Aurora“:GIKI Science Society publishes a scientific maga-zine named “AURORA”, the one in your hand. This contains articles and essays not only specific to the general sciences but also caters the latest inven-tions, scientific theories and upcoming technologi-cal developments. It also contains research papers of renowned professors, an interview of a famous scientist of Pakistan and final year project abstracts of students in GIKI. It is not only distributed among the students of GIKI but also to the major universi-ties and R&D organizations all over the country.