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WilliamRowanHamilton18051865
ZeranColburnAmericanchildprodigy
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"Heusedtocarryonlongtrainsofalgebraicandarithme8calcalcula8onsinhismind,duringwhichhe
wasunconsciousoftheearthlynecessityofea8ng..."
WilliamEdwinHamilton(hiselderson)
Rowanandson
Whowouldnotratherhavethefame
ofArchimedesthanthatofhis
conquerorMarcellus?
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1868MapofLafaye>e,Indiana
FirstUSAirmailFlight,Lafaye>e,Indianain1859
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1878MapofChaunceyshowingPurdueUniversityGrantSt. Northwestern
University
Hall
PurdueUniversitywasfoundedin1869.Classesstartedin1874.
ThefirstdegreewasaBachelorofScienceinChemistryawardedin1875.
Competed
in1874
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1862Rail-RoadandMilitaryMapoftheUS
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JosiahWillardGibbs
1839-1903
Oneoftheprincipalobjectsoftheorecalresearchinanydepartmentofknowledge
istofindthepointofviewfromwhichthesubjectappearsinthegreatestsimplicity.
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Max Karl Ernst Ludwig Planck1858 - 1947
19011878
Sciencecannotsolvetheulmatemysteryofnature.Andthatisbecause,inthe
lastanalysis,weourselvesareapartofthemysterythatwearetryingtosolve.
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FromthePrefacetoGibbsStascalMechanics(1901)
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HeatCapaciesofGasesandSolids
Diamond
Theobservedtemperaturedependenceimpliesthat
molecularvibraIons(androtaIons)
arequanIzed,justlikephotons! Energy
LowT HighT
Inacve Acve
Classicalpredic8on:
U=aT
Heat
Capacity:
Cv=(dU/dT)v
=a
ExpectCVtobe
T-independentBoltzmann
distribuWon = h
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Albert Einstein1879- 1955
Themostincomprehensiblethinkabouttheworldis
thatitiscomprehensible.
192118931904
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AlbertEinsteinsRelavityandE=mc2(1905)
Atom velocity
m = E/c2
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PhotoelectricEffect
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=hphotonenergy
Frequency
oflight
EinsteinsExplanaonofthePhotoelectricEffect(1905)
Plancks
Constant
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Movie
EinsteinsExplanaonofBrownianMoon(1905)
ProvedthatmoleculesreallyexistDeterminedAvogadrosnumber,NA
Mean-squared
displacementRadius Viscosity Time
Allofthesequan88esare
experimentallymeasurable
Animation
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What Happened in Lubeck in 1895?
A shouting match between the atomist and the energist
Which was which?Who won the day?
WilhelmOstwald LudwigBoltzmann
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GeorgHelm(speaker,wrotetohiswife):
Thegreatac8vityliesbehindme.Ibelievethatthelecturewasasuccess,itwasapplaudedandpraised;
butduringthediscussiontherewasas8fffight.
Boltzmanncommencedwithfriendlyapprecia8ve
remarksand[then]begantoinveighagainst
OstwaldsandmyworkOstwaldandBoltzmanncame
toheavyblowsThemee8nglastedfrom9un8laer
12Thehallwasmorethanhalffull,sothatafew
hundredpersonsexperiencedthewholebusiness
Personal Accounts of the Lubeck Conference
ArnoldSommerfeld(audiencemember):
Thechampionofenerge8cswasHelm;behindhimstoodOstwaldandbehindbothofthemthephilosophy
ofMach(whowasnotpresentinperson).Thebale
betweenBoltzmannandOstwaldwasmuchliketheduel
ofabullandasupplebullfighter.However,this8methe
bulldefeatedthetoreadorinspiteofallhisagility.The
argumentsofBoltzmannstruckthrough.Weyoung
mathema8cianswereallonBoltzmannsside
Ostwald(recountedyearslater):Atthediscussion[inLubeck]Ifoundmyselfbeforea
closedantagonism.Myonlysupporterandfigh8ng
companionwasGeorgHelm.Buthewasremovedfrom
mebecauseofhisaversiontoarealis8cconcep8onof
energyItwasthefirst8methatIpersonallyfound
myselfconfrontedbysuchaunanimousbandofdownrightadversaries
(inhisbookwrienin1909):[Boltzmannis]themanwhoexcelledallofusinacumen
andclarityofhisideas.
Boltzmann(GasTheory,PartII,19):WhenthefirstpartofGasTheorywasbeingprinted[in195]
Itwasjustatthis8methataacksonthetheoryofgases
begantoincrease.Iamconvincedthattheseaacksare
merelybasedonmisunderstanding,andthattheroleofgas
theoryinsciencehasnotyetbeenplayedoutInmyopinionit
wouldbeagreattragedyforscienceifthetheoryofgases
weretemporarilythrownintooblivionbecauseofamomentaryhos8leatudetowardit,aswasforexamplethe
wavetheorybecauseofNewtonsauthorityIamconsciousof
beingonlyanindividualweaklystrugglingagainstthestream
of8me.
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Einstein(leertoOstwald,1901):
EsteemedHerrProfessor!Becauseyourbookongeneralchemistry
inspiredmetowritetheenclosedar8cle,Iam
takingthelibertyofsendingyouacopyofit.On
thisoccasionpermitmealsotoinquirewhether
youmighthaveuseforamathema8calphysicist
familiarwithabsolutemeasurements...becauseI
amwithoutmeans,andonlyaposi8onofthis
kindwouldoffermethepossibilityofaddi8onal
educa8on.
Respecullyyours,AlbertEinstein
(givestheaddressofhisparents)
Threeweekslaterhewroteagain:
EsteemedHerrProfessor!
AfewweeksagoItookthelibertyofsending
youfromZurichashortpaperwhichIpublishedin
Wiedemann'sAnnalen.Becauseyourjudgment
ofitmaersverymuchtome,andIamnotsure
whetherIincludedmyaddressintheleer,Iam
takingthelibertyofsendingyoumyaddress
hereby.Respecully...
EinsteinsFather(leertoOstwald,1901):EsteemedHerrProfessor!
Pleaseforgiveafatherwhoissoboldastoturntoyouin
theinterestofhisson.Ishallstartbytellingyouthatmy
sonAlbertis22yearsold,thathestudiedattheZurich
Polytechnikumfor4years,andthathepassedhisdiploma
examina8onsinmathandphyswithflyingcolorslast
summer.Sincethen,hehasbeentryingunsuccessfullyto
obtainaposi8onasanAssistant,whichwouldenablehim
tocon8nuehiseduca8onintheore8cal&experimental
physics.Allthoseinposi8ontogiveajudgmentinthe
maer,praisehistalents;inanycase,Icanassureyouthat
heisextraordinarilystudiousanddiligentandclingswith
greatlovetohisscience.
Mysonthereforefeelsprofoundlyunhappywithhis
presentlackofposi8on,andhisideathathehasgoneoff
thetrackswithhiscareer&isnowoutoftouchgetsmore
andmoreentrenchedeachday.Inaddi8on,heis
oppressedbythethoughtthatheisaburdenonus,peopleofmodestmeans.
Sinceitisyou...whommysonseemstoadmireand
esteemmorethananyotherscholarcurrentlyac8vein
physics...[Imake]thehumblerequesttoreadhis
paper...andtowritehim,ifpossible,afewwordsof
encouragement,sothathemightrecoverhisjoyinliving
andworking
Why did Einstein Write to Ostwald?
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FromtheprefacetoOutlinesofGeneralChemistrybyW.Ostwald(1912).
BoltzmannsandEinsteinstheore8calcontribu8onsareacknowledgedonp.45.
Ostwald Accepts the Atomic Hypothesis
I am now convinced that we have recently become possessed of
experimental evidence of the discrete or grained nature of maer,
which the atomic hypothesis sought in vain for hundreds and
thousandsofyears.Theisola8onandcoun8ngofgasions,ontheone
hand, which have crowned with success the long and brilliant
researchesofJ. J.Thomson,and,ontheother,theagreementoftheBrownianmovementswiththerequirementsofthekine8chypothesis,
establishedbymany inves8gators andmost conclusively byJ.Perrin,
jus8fythemostcau8ousscien8stinnowspeakingoftheexperimental
proofof the atomic nature ofmaer. The atomic hypothesis is thus
raisedtotheposi8onofa scien8ficallywell-founded theory,and can
claim its place in a text-book intended as an introduc8on to the
presentstateofourknowledgeinGeneralChemistry.
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Einsteins Miracle Year (1905)
Einstein:NobelPrizeinPhysics1921"forhisservicestoTheore8calPhysics,andespecially
forhisdiscoveryofthelawofthephotoelectriceffect"
Relativity E=mc2 Light Particles Brownian Motion
The first person that Ostwald nominated for a Nobel Prize was Albert Einstein
Ostwald:NobelPrizeinChemistry"inrecogni8onofhisworkoncatalysisandforhis
inves8ga8onsintothefundamentalprinciplesgoverning
chemicalequilibriaandratesofreac8on"
Ostwalds Nobel Prize (1909)
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LineSpectraofAtomsandMolecules
MoleculesappeartohavequanIzedenergies!
RotaonofCO2 VibraonsofaNano-Ice-Cube
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In1912Neilswrotetohisbrother,Harald:
Thingsaregoingratherwell,forIbelieveIhavefoundoutafewthings;but,
tobesure,IhavenotbeensoquicktoworkthemoutasIwasstupidtothink.
NielsHenrikDavidBohr
(1885-1962)
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EnergiesofPhotonsandMolecules
Figure1.2inUnderstandingPhysicalChemistry
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Wave-ParIcleDuality
AlbertEinstein LouisdeBroglie
=h=hc/Momentum
PlancksConstant
p=h/Energy
Frequency Wavelength
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DiffracIonofWaves
ThomasYoung'ssketchoftwo-slitdiffrac8on103.
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DiffracIonofElectrons
DiscoveredaccidentallybyDavissonandGermer1927atBellLabs
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MolecularDiffracIonHeandH2byRocksalt
ExperimentalDataofOoStern19301943
1913
DuringtheyearthatStern
spentasEinsteinsfirst
postdoctoralassociate
Stern Einstein
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rwinSchroedinger
DevelopedWaveEquaIonWhichPredicts
QuanIzaIonofAtomic&MolecularEnergies
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VibraIonalNormalModesofaString
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2-DVibraIonalNormalModes
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3-DNormalModes
x
yz
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StaIsIcallyndependentProbabiliIesMulIply
P()=P()P()=1/6x1/6=1/36
P()=P()P()=1/2x1/2=1/4
Molecular
KineIc
Energies
x=
1
2mv
x
2
y
=1
2mv
y
2
z=
1
2mv
z
2
P(x +y +z) = P(x )P(y )P(z )
P(i) eci
P(x +
y +
z) e
c(x +y +z ) e
cxecxe
cz P(x )P(y )P(z)
So,
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BarometricDistribuIonofAtmosphericDensity
Use,idealgaslaw
andgravitaIonal
potenIalenergy
=
mgh
Toobtain,
P()
0
= emgh / kBT
= e / kBT
1/kBTSo,
Height,h
Denisty, !!0
!(h)
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Eq.1.24inUPC
= h
=1/kBTor1/RT