Philosophical Aspects Of Modern Scientific Endeavour What does Quantum Mechanics, Relativity, Strings, Super Symmetry Say? From Newton to Einstein to Stephen Hawking , Roger Penrose, Feynman and Beyond By Shripadraj Mujumdar [Prasanna Deep Questions Answered ! Deeper Questions Posed !!
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Philosophical Aspects Of Modern Scientific Endeavour
What does Quantum Mechanics, Relativity, Strings, Super Symmetry Say? From Newton to Einstein to Stephen Hawking , Roger Penrose, Feynman and Beyond
By Shripadraj Mujumdar [Prasanna]
Deep Questions Answered ! Deeper Questions Posed !!
Business, Financial, Market , Inflation,
Regulation, Relations
What is the physical reality?
What is everything made up of?
Where do we stand at Cosmic Level? Is it too Big? Too small?
How did it all Start ?
What laws govern everything?
What and How do we perceive?
Are there hidden dimensions which we do not see?
Do we have any special position in the Universe ?
The questions are as old as human curiosity.
The answers to many have always seemed beyond the reach of science and reasoning. . .until now!
Cosmic Vision
P e r s p e c t i v e s
Our Huge Planet is approx.10000000000000000000 Times Smaller
Than Visible Universe
What is our Home Address Really in the whole Universe?
• Matter -uniformly throughout • smaller length-scales, matter clustered
Atoms are condensed into STARS, • Most stars into GALAXIES• Most galaxies into CLUSTERS, SUPER
CLUSTERS • the largest-scale structures such as the
Great Wall of galaxies. • Isotropically , same content• Bathed in a highly MICROWAVE
RADIATION
The universe
93 billion light years across
Across
Universe in ceaseless motion.
Creation and Death of Stars
Explosions, Supernova, Merging
Black Holes and Cosmic Radiation
Seen or Perceived Trough Light, Infrared, Microwave Continuously Expanding
very large and possibly infinite in volume; the observable matter is spread over a space at least
Inflation(Big Bang plus 10-34 Seconds)
Big Bang plus 300,000 Years
gravitational waves
Big Bang plus 14 Billion Years
light
Now
Space, time, matter-everything originated in the Big Bang, an incommensurably huge explosion that happened 13.7 billion years ago.
incredibly hot and dense but only a few moments after, rise to the building blocks of matter – in particular, the quarks and electrons of which we are all made.
A few millionths of a second later, quarks aggregated to produce protons and neutrons, which in turn were bundled into nuclei three minutes later.
Took 380,000 years for electrons to be trapped in orbits around nuclei, forming the first atoms.
Mainly helium and hydrogen, which are still by far the most abundant elements in the Universe.
Another 1.6 million years later, gravity began to take control as clouds of gas began to form stars and galaxies.
Since then heavier atoms, such as carbon, oxygen and iron, of which we are all made, have been continuously ‘cooked’ in the hearts of the stars and stirred in with the rest of the Universe
Motion
Space
Time
Matter
Mass and Energy
Light
Its Not correct!! ?-Only Locally/Reference Frame
Classical physics
an absolute, three-
dimensional space,
independent of the material
objects
Euclidean geometry
time as a separate
dimension which again is
absolute and flows at an
even rate.
Governing Theories
Einstein recognized that temporal specifications, too, are relative and depend on the observer.
In everyday life, the impression that we can arrange the events around us in a unique time sequence is created by the fact that the velocity of light is so high, compared to any other velocity we experience, that we can assume we are observing events at the instant they are occurring
What is true for lengths is also true for time intervals, This means that clocks in motion run slower; time slows down
Time passes more slowly for observers traveling at high speeds or near a massive body.
It is important to realize that it makes no sense to ask which is the ‘real’ length of an object, just as it makes no sense in our everyday life to ask for the real length of somebody’s shadow
Space-time instead of Space & Time – 4 Dimensional E=mc2 --mass (m) is equivalent to energy (E). The recognition that the two quantities are related was
Einstein’s stroke of genius. So your car, and virtually all other activity on Earth, is
ultimately powered by E=mc2.
Einstein changed the way we think of the Universe The Theory of Relativity:
Flat sheet like rubber [4D]- with deeps and holes-Due to GRAVITY
Motion
Space
Time
Matter
Mass and Energy
Light
All IntegratedNow Its Universally defined!
Classical physics
an absolute, three-
dimensional space,
independent of the material
objects
Euclidean geometry
time as a separate
dimension which again is
absolute and flows at an
even rate.
11
Einstein’s “Predictions”Three startling outcomes of Einstein’s general
relativity:
The expansion of the Universe (from a Big Bang) Black holes A Cosmological Constant acting against the pull of gravity
Hubble discovered the expanding Universe
in 1929
Black holes found in our Galaxy and at the centers of most galaxies
over the past three decades
Evidence for an accelerating Universe
was observed in 1998
Dark matter, Black Holes- (But Are not so black) As the star collapses and becomes more and more dense,
the force of gravity on its surface becomes stronger and stronger, and consequently the space-time around it becomes more and more curved.
Because of the increasing force of gravity on the star’s surface, it becomes more and more difficult to get away from it, and eventually the star reaches a stage where nothing-not even light-can escape from its surface.
At that stage, we say that an ‘event horizon’ forms around the star, because no signal can get away from it to communicate any event to the outside world.
The space around the star is then so strongly curved that all the light is trapped in it and cannot escape.
We are not able to see such a star, because its light can never reach us and for this reason it is called a black hole
Matter accounts for only a tiny 4% of the entire Universe. In a way, it is not so much the visible things, such as planets and galaxies, that define the Universe, but rather the void around them!
Most of the Universe is made up of invisible substances known as 'dark matter' (26%) and 'dark energy' (70%). Do not emit electromagnetic radiation, and we detect them only through their gravitational effects.
We do not know what 95% of the universe
is made of!
Perspectives
We and all things around us are made of atoms?
Human Hair ~ 50 mm = 50 10-6 m = 0.000050 m
Atom ~ 10-10 m = 0.0000000001 m
Atoms
Atoms are all similarly made of:- protons and neutrons in the nucleus- electrons orbiting around
electron
proton
neutron
Protons, neutrons are made up of quarks
The electron was thefirst elementaryparticle to be discovered(JJ Thomson 1897)
From the atom to the quark
Atoms and sub-atomic particles are much smaller than visible light wave-length Therefore, we cannot really See Them. .
To learn about the sub-atomic structure we need particle accelerators
How small are the smallest constituents of matter?
~ 10-10 m~ 10-14 m
~ 10-15 m
<10-18 m
<10-1 8
m
Quarks are fundamental building blocks of matter. They are most commonly found inside protons and neutrons, the particles that make up the core of each atom in the universe.
Probing the detailed properties of the top may shed light on the
origins of mass itself in the universe.
Based on current experimental evidence, quarks seem to be truly fundamental particles; they cannot be further subdivided.
Anti-matterFor every fundamental particle of matter there is an anti-
particle with same mass and properties but opposite charge
ne
e-
u
d-1/3
+2/3
ne
e+
u
d+1/3
-2/3
+1
0
-1
0
positron
• Correspondent anti-particles exist for all three families• Anti-matter can be produced using accelerators
Matter Anti-Matter
Bar on top to indicateanti-particle
Is the whole Universe made only of quarks and electrons?
n1 cm
Within each cm3 of space: ~300 neutrinos
from Big Bang
Neutrinos are everywhere! in the outer space, on Earth, in our bodies..
1 cm
No! There are also neutrinos!
Neutrinos are the most abundant matter-particles in the Universe!
1014 neutrinos per second from Sun
are zipping through you
nEvery cm2 of Earth surface is crossed every
second by more than 10 billion (1010) neutrinos produced in the Sun
The 4 forces of NatureWeak• Beta-decay• pp fusion
Strong• Quark binding
Electromagnetic• TV, PCs • Magnets
• e- e+ creation
GravityResponsible ofKeeping us well-planted on earth
Electric charge
mass
weak charge
strongcharge
Yet Many Loose ends Is there no mass?!!
The Higgs boson, a fundamental particle predicted by theorist Peter Higgs, may be the key to understanding why elementary particles have mass
Higgs proposed that the vacuum contains an omnipresent field that can slow down some (otherwise mass less) elementary particles—like a vat of molasses slowing down a high-speed bullet. Such particles would behave like massive particles traveling at less than light speed. Other particles—such as the photons of light—are immune to the field: they do not slow down and remain mass less.
Although the Higgs field is not directly measurable, -particles called Higgs bosons. So far, experiments using the world's most powerful accelerators have not observed any Higgs bosons, but indirect experimental evidence suggests that particle physicists are poised for a profound discovery.
String theory An approach to the construction of a complete unified theory of all
fundamental particles and forces. Fundamental constituents of the universe are one-dimensional
“strings” rather than point-like particles. What we perceive as particles are actually vibrations in loops of
string, each with its own characteristic frequency. String theory originated as an attempt to describe the interactions
of particles such as protons six or seven extra dimensions of space, and it contains ways of
relating large extra dimensions to small ones. led to the concept of Supersymmetry, which would double the
number of elementary particles. Practitioners are optimistic that string theory will eventually make
predictions that can be experimentally tested. String theory has already had a big impact on pure mathematics, cosmology and the way particle physicists interpret experiments,.
Supersymmetry
A proposed property of the universe. Superpartner. - a heavy replica of a particle, with one other
significant difference. All particles are classed as either fermions or bosons. Superpartner - thereby "balancing the books" and making
nature symmetric. E.g. the superpartner of an electron (a fermion) is called a selectron (a boson).
grand dance of particles through the universe, but we can currently see only one partner from each pair. The unseen particles might be the source of the mysterious
"dark matter" in galaxies. Although super partners have not yet been observed in
nature, they might soon be produced in particle accelerators on Earth- LHC
Extra Dimensions Extra dimensions sound like science
fiction, but they could be part of the real world. And if so, they might help explain mysteries like why the universe is expanding faster than expected, and why gravity is weaker than the other forces of nature. Three dimensions are all we see -- how could there be any more? Einstein's general theory of relativity tells us that space can expand, contract, and bend. If one direction were to contract down to an extremely tiny size, much smaller than an atom, it would be hidden from our view. If we could see on small enough scales, that hidden dimension might become visible.
Imagine a balancing act in which a daredevil walks the cable of a suspension bridge, only able to move backward and forward, not left and right, nor up and down. The daredevil experiences only one dimension, but things that live on a smaller scale, such as ants, can move about in an extra dimension -- circularly around the cable, in this analogy. String theory requires the existence of extra dimensions. Perhaps we will be fortunate enough to detect them directly in upcoming experiments, or infer their existence from early-universe cosmology. If so, we will have yet another confirmation of how the universe extends well beyond our everyday experience.
1. What is Dark Matter?2. What is the Nature of Dark Energy?
3. How Did the Universe Begin?4. Did Einstein Have the Last Word on Gravity?
5. What are the Masses of the Neutrinos and HowHave They Shaped the Evolution of the Universe?
6. How do Cosmic Accelerators Work and What areThey Accelerating?
7. Are Protons Unstable?8. What Are the New States of Matter at Exceedingly
High Density and Temperature?9. Are There Additional Space-Time Dimensions?10. How Were the Elements from Iron to Uranium
Made?11. Is a New Theory of Light and Matter Needed at
the Highest Energies?
1. Are there undiscovered principles of nature : New symmetries, new physical laws?
2. How can we solve the mystery of dark energy?3. Are there extra dimensions of space?
Do all the forces become one?4. Why are there so many kinds of particles?5. What is dark matter?6. How can we make it in the laboratory?7. What are neutrinos telling us?8. How did the universe come to be?9. What happened to the antimatter?
?
Deeper Questions!
The largest machine in the world...The fastest racetrack on the planet...
The emptiest space in the Solar System...
The hottest spots in the galaxy, but even colder than outer space...
ALICE ATLAS CMS LHCb
TOTEM LHCf
The most powerful supercomputer system in the world...
We are at a special moment in our journey to understand the universe and the physical laws that govern it
-Committee on the Physics of the Universe [ U.S. Gov]
“Up to now, most scientists have been too occupied with the development of new
theories that describe what the universe is to ask the question why. On the other hand, the people whose business it is to ask why, the
philosophers, have not been able to keep up with the advance of scientific theories.
However, if we do discover a complete theory, it should in time be understandable in broad principle by everyone, not just a few scientists. Then we shall all, philosophers, scientists, and just ordinary people, be able to take
part in the discussion of the question of why it is that we and the universe exist. If we find the answer to that, it would be the ultimate triumph of human
reason – for then we would know the mind of God.” Stephen Hawking