Relativity Matters: From Einstein's EMC2 to Laser Particle Acceleration and Quark-Gluon Plasma

478 Pages·2017·6.66 MB·English

by  Johann Rafelski (auth.)

Johann Rafelski
Relativity
Matters
From Einstein’s EMC2
to Laser Particle Acceleration
and Quark-Gluon Plasma
Relativity Matters
Johann Rafelski
Relativity Matters
From Einstein’s EMC2 to Laser Particle
Acceleration and Quark-Gluon Plasma
With Exercises, Examples and Discussions
JohannRafelski
DepartmentofPhysics
TheUniversityofArizona
Tucson,AZ,USA
ISBN978-3-319-51230-3 ISBN978-3-319-51231-0(eBook)
DOI10.1007/978-3-319-51231-0
LibraryofCongressControlNumber:2017935709
©SpringerInternationalPublishingAG2017
Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartofthemate-
rialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation,broadcasting,
reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionorinformationstorageandretrieval,
electronicadaptation,computersoftware,orbysimilarordissimilarmethodologynowknownorhereafterde-
veloped.
Theuseofgeneraldescriptivenames,registerednames,trademarks,servicemarks,etc.inthispublicationdoes
notimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfromtherelevantprotective
lawsandregulationsandthereforefreeforgeneraluse.
Thepublisher,theauthorsandtheeditorsaresafetoassumethattheadviceandinformationinthisbookare
believedtobetrueandaccurateatthedateofpublication.Neitherthepublishernortheauthorsortheeditors
giveawarranty,expressorimplied,withrespecttothematerialcontainedhereinorforanyerrorsoromissions
thatmayhavebeenmade.
Printedonacid-freepaper
ThisSpringerimprintispublishedbySpringerNature
TheregisteredcompanyisSpringerInternationalPublishingAG
Theregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,Switzerland
Dedicatedtothememoryofmyacademicteacher
Prof.Dr.Dr.h.c. mult.WalterGreiner
(29October1935–5October2016)
Preamble
ThisbookpresentsSpecialRelativity(SR)inlanguageaccessibletostudentswhileavoid-
ingtheburdenofgeometry,tensorcalculus,andspace-timesymmetries,yetadvancingin
highlycontemporarycontextallthewaytoresearchfrontiers.Ifurthertakeintoconsider-
ationthewayEinsteinsawSRafter1915asapartofthemoregeneralscientificcontext,
with the newly formulated General Relativity (GR) influencing the way SR was under-
stood. This is complemented by the current cosmological perspective and connected to
present day research topics. SR is presented such that nothing remains a paradox or just
apparent,butrathereverythingisexplained.
WefirstdevelopthebasicprinciplesofSR,andexploreanddiscussalternatives.Much
of the first half of the book has the format of a discussion in which the teacher, and in
particularhisgraduatestudent,willbechallengedbyabrilliantbutweb-self-taughtstudent
called‘Simplicius’.1
These conversations are representative of both the foundational concepts in SR and
howstudentshavechallengedthisauthorovertheyears.Theseconversationspresentthe
opportunitytoexplorewhatoftenremainsunsaidwhenteachingSRandoftenexplainhow
oneshouldthinkaboutSR.Theyarealsoinresponsetotherealizationthatmany‘Modern
Physics’textscontainseriousmisunderstandingsoftheprinciplesofSR.Thesefindtheir
wayintoweb-based,andevensomeclassroomteaching.
As the book progresses, the qualitative and historical discussion turns into textbook-
stylepresentation,andattheendevolvesintotheconciseandpreciseformatofaphysics
research book. The final 100 pages reveal research topics and unresolved questions re-
latedtorelativisticchargedparticledynamics.Thereaderreachingthemiddleofthisbook
1SimplicioappearsinGalileoGalilei’sDialogueConcerningtheTwoChiefWorldSystems(1632)
comparingtheCopernicanwiththePtolemaicparadigm.Thebookispresentedasaseriesofdiscus-
sionsamongtwophilosophersandSimplicio,laymandefenderoftheAristoteliangeocentricviewon
astronomy.SimpliciusofCilicia,c.490–c.560,wasaGreco-Romanmathematicianandphilosopher
whowroteextensivelyontheworksofAristotle.
vii
viii Preamble
needsagoodcommandofelementaryalgebraandthebasicknowledgeofcalculusalong
with introductory knowledge of classical mechanics and, ultimately, electrodynamics at
thelevelofMaxwell’sequations.
Atextofsimilarcharacter,content,scope,hasnotbeenpresentedbefore.Thesearchfor
clarityinthefundamentalquestionsaboutSR,thedevelopmentsafter1905,andthestrong
connectiontocurrentresearchtopicsare,inmyview,themostimportantandoriginalas-
sets of this book. Readers should keep in mind that I do not invent relativity, but report
and interpret the development and the progress of the theoretical framework, with many
conceptualdevelopmentsreachingfarbeyondtheinitialideas.ThosewhocherishSpecial
Relativityof1905vintageshouldrememberthatin1918–1922Einsteindisavowedpubli-
cation of his 1912 Special Relativityreview, whichhad been delayedby the outbreak of
WWI.Lookingatthismanuscript2 afterreadingthisbook,theanswerto‘why’shouldbe
clear:by1920thescientificcontexthadevolved.Today,ofcourse,ithasevolvedfurther.
Backgroundremarks
Intheearly1980swhenteachingatUniversityofFrankfurtIwrotemyfirstbookonSR.3
PublishedinWalterGreiner’s“TheoreticalPhysics”series,thisvolumewaswellreceived
inthreeeditions.WalterknewthereweresignificantproblemsinmanytextsexplainingSR;
thusheencouragedandsupportedthisproject.Lookingtodayatthis1980–1990effort,it
wasgoodbutnotcomplete.Thecurrentvolumeisverydifferent,buthasitsbasisinthat
firstexperience.
A few years later I asked John S. Bell, a friend and mentor, which English language
book to use to teach relativity. I reproduce his letter and some key words are here: John
said “...recommend ...my own paper ...Einstein approach is ...pedagogically danger-
ous...”.BetweenthelinesJohnarguesthatthebookIwasseekingneededtobewritten.
IofcourseagreedasmyGermanlanguagerelativitybookalignedwellwithBell’sthink-
ing.Inthepast25+yearsIwason-offinrespecttowritinganewtext,andImadesureto
takeJohn’sadvicetofollowthehistoricalapproach,clarifyingwhyEinstein’srelativisti-
callyinvariantætherisdifferentfromtheLorentzandLarmorpointsofview.
2The manuscript is published as a facsimile of the original hand written document, with English
translationandhistoricalintroduction:A.EinsteinandH.Gutfreund,Einstein’s1912Manuscripton
theSpecialTheoryofRelativity,ISBN0807615323(GeorgeBraziller2004).
3Spezielle Relativitätstheorie, Verlag Harri Deutsch, Frankfurt (1984, ISBN3-87144-711-0; 1989,
ISBN3-97171-1063-4;and1992ISBN3-8171-1205-X).
Preamble ix
JohnSBell’sanswerofMarch12,1985about“HowtoteachSpecialRelativity”,
thetitleofthelengthyconferencepaperhesentalongwiththeletter.
Acknowledgments
During the past three decades, each time I taught a SR related class, I made progress in
thisnewtext.Severalstudentscontributedtothewritingandvettingofthisbook.Ithank
in particular, (alphabetically) Jessica Bernier, Rebekah Cross, Stefan Evans, Martin For-
manek,KielHowe,TaylorKessinger,Will Parker,DanielRosser, andPerSchmidt.Kiel
Howe helped with some of the graphic material in the book, and challenged me in the
waythatledtothecreationoftheconversationcontents.IthankVictoriaGrossackforher
encouragementandeditorialsupportoverthepastdecade.
Ibenefitedgreatlyfromalonglistofcriticalcommentspreparedin2010“allsummer
long” by Iwo Bialynicki-Birula, of the Centrum Fizyki Teoretycznej, Polish Academy
of Sciences in Warsaw. Iwo’s crisp and critical mind was an invaluable help for me in
x Preamble
realizing why the 2010 version of this book could be considerably improved. Iwo took
deep interest in this manuscript; his criticism, comments, and questions influenced the
precisefinalformatofthisvolume.
Ithankallthoseinvolvedfortheirkindhelpandinterest.Iamaloneresponsibleforany
errors,omissions,andpersonalhistoricalremarksandanecdotesinthecontentspresented
here.
Tucson,Arizona,USA JohannRafelski
Summer2016
Contents
Preamble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Guidetocontents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Manyreasonstowritethisbook . . . . . . . . . . . . . . . . . . . . . . . . xix
Specialrelativitymatters. . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
Accelerationfrontierofphysics . . . . . . . . . . . . . . . . . . . . . . . . xxiv
Frequentlyusedabbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . xxv
PartI Space-Time,LightandtheÆther
1 Space-Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Time,anew4thcoordinate . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Measuringspaceandtime . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Speedoflightandtheæther . . . . . . . . . . . . . . . . . . . . . . . 9
2 TheMichelson-MorleyExperiment . . . . . . . . . . . . . . . . . . . . . 21
2.1 Earth’smotionandtheæther . . . . . . . . . . . . . . . . . . . . . . 21
2.2 Principleofrelativity . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.3 Cosmicmicrowavebackgroundframeofreference . . . . . . . . . . . 27
3 MaterialBodiesinSpecialRelativity . . . . . . . . . . . . . . . . . . . . 29
3.1 Timedilation,bodycontraction . . . . . . . . . . . . . . . . . . . . . 29
3.2 RealityoftheLorentz-FitzGeraldbodycontraction . . . . . . . . . . . 31
3.3 PathtowardsLorentzcoordinatetransformations . . . . . . . . . . . . 39
3.4 Highlights:howdidrelativity‘happen’? . . . . . . . . . . . . . . . . 41
xi