Fashion, Faith, and Fantasy in the New Physics of the Universe

518 Pages·2016·5.09 MB·English

by  Roger Penrose

Acknowledgements
Thisbook’ssomewhatlengthygestationhasfadedmymemoryofthesourcesof
many contributions to its development. To such helpful but anonymous friends
andcolleaguesIofferbothmygratitudeandapologies.Thereareofcourseothers
whom I clearly owe especial thanks, most particularly my long-time colleague
Florence Tsou (Sheung Tsun) for her enormous help (also with her husband
ChanHong-Mo)regardingparticlephysics.Myevenlonger-timecolleagueTed
(Ezra)Newmanhasprovidedcontinualinsightsandsupportovermanyyears,and
I benefited greatly from the knowledge and understandings ofAbhayAshtekar,
KrzysztofMeissner,andAndrzejTrautman.OxfordcolleaguesPaulTod,Andrew
Hodges,NickWoodhouse,LionelMason,andKeithHannabusshavealsogreatly
influenced my thinking. I have learned much of approaches to quantum gravity
fromCarloRovelliandLeeSmolin.SpecialthanksgotoShamitKachruforhis
carefulstudyofearlierdraftsofthisbook,andalthoughIdoubthewillbehappy
with its expressed sentiments regarding string theory, his criticisms have been
greatlyhelpfulinreducingerrorsandmisunderstandingsonbothsides.
For input of various kinds I am grateful to Fernando Alday, Nima Arkani-
Hamed,MichaelAtiyah,HarveyBrown,RobertBryant,MarekDemianski,Mike
Eastwood,GeorgeEllis,Jo¨rgeFrauendiener,IvetteFuentes,PedroFerreira,Vahe
Gurzadyan,LucienHardy,DennyHill,LaneHughston,ClaudeLeBrun,Tristan
Needham,SaraJonesNelson,PawelNurowsski,JamesPeebles,OliverPenrose,
SimonSaunders,DavidSkinner,GeorgeSparling,JohnStatchel,PaulSteinhardt,
LennySusskind,NeilTurok,GabrieleVeneziano,RichardWard,EdwardWitten,
andAntonZeilinger.
RichardLawrenceandhisdaughterJessicahavebeeninvaluableforproviding
numerousfacts.Forhelpinadministrativeways,IthankRuthPreston,FionaMar-
tin,PetronaWinton,EdytaMielczarek,andAnnePearsall.Iamsupremelygrateful
toVickieKearnofthePrincetonUniversityPressforherenormouspatience,sup-
port, and encouragement, and to her colleagues CarminaAlvarez for her cover
designandKarenFortgangandDimitriKaretnikovfortheirguidancewithregard
todiagrams,andtoJonWainwrightofT&TProductionsLtdforhiscarefulediting.
Finally, my wonderful wifeVanessa has kept me going, through difficult times,
withherlove,criticalsupport,andtechnicalexpertise–oftenmagicallyrescuing
ix
x Acknowledgements
me from seemingly hopeless entanglements with my computer. Huge thanks to
her and also to our teenage son, Max, whose technical know-how and loving
supporthavebeeninvaluable.
ILLUSTRATION CREDITS
Theauthorgratefullyacknowledgesthecopyrightholdersofthefollowingfigures:
Figure1-35:AfterRovelli[2004].
Figure1-38:M.C.Escher’sCircleLimitI (cid:2)c 2016TheM.C.EscherCompany–
TheNetherlands.Allrightsreserved.www.mcescher.com
Figure3-1:M.C.Escher’s(a)PhotoofSphere,(b)SymmetryDrawingE45,and
(c) Circle Limit IV (cid:2)c 2016 The M. C. Escher Company–The Netherlands.All
rightsreserved.www.mcescher.com
Figure3-38(a)and(b):From“CosmicInflation”byAndreasAlbrecht,inStruc-
ture Formation in the Universe (ed. R. Crittenden and N. Turok). Used with
permissionofSpringerScienceandBusinessMedia.
Figure3-38(c):From“InflationforAstronomers”byJ.V.NarlikarandT.Padman-
abhanasmodifiedbyEthanSiegelin“Whywethinkthere’saMultiverse,notjust
our Universe” (https://medium.com/starts-with-a-bang/why-we-think-theres-a
-multiverse-not-just-our-universe-23d5ecd33707#.3iib9ejum).Reproducedwith
permissionofAnnualReviewofAstronomyandAstrophysics,1September1991,
Volume29(cid:2)c byAnnualReviews,http://www.annualreviews.org.
Figure3-38(d):From“EternalInflation,PastandFuture”byAnthonyAguirre,
in Beyond the Big Bang: Competing Scenarios for an Eternal Universe (The
FrontiersCollection)(ed.RudyVaas).UsedwithpermissionofSpringerScience
andBusinessMedia.
Figure3-43:CopyrightofESAandthePlanckCollaboration
Allotherfigures(exceptingthecomputercurvesinfigures2-2,2-5,2-10,2-25,
3-6(b),A-1,A37,A-41,A-44,andA-46)weredrawnbytheauthor.
Preface
ARE FASHION, FAITH, OR FANTASY RELEVANTTO
FUNDAMENTAL SCIENCE?
ThisbookhasbeendevelopedfromanaccountofthreelecturesIgaveatPrinceton
University in October 2003 at the invitation of Princeton University Press.The
titleIhadproposedtothePressfortheselectures–Fashion,Faith,andFantasy
intheNewPhysicsoftheUniverse–andwhichremainsasthetitleofthisbook
may well have been a somewhat rash suggestion on my part.Yet it genuinely
expressed a certain unease I felt about some of the trends that were part of the
thinkingofthetimeconcerningthephysicallawsgoverningtheuniverseinwhich
we live.Well over a decade has passed since then, but the topics, and much of
whatIhadtosayaboutthem,appeartobe,forthemostpart,atleastasrelevant
todayastheywerethen.Igavethosetalkswithsomeapprehension,Imightadd,
asIwastryingtoexpresssomepointsofviewthatIworriedmightresonatenot
toofavourablywithmanyoftheresidentdistinguishedexperts.
Each of the eponymous words “fashion”, “faith”, and “fantasy” suggests a
quality that would seem to be very much at odds with the procedures normally
considered appropriate when applied to a search for the deep principles that
underlie the behaviour of our universe at its most basic levels. Indeed, ideally,
it would be very reasonable to assert that such influences as fashion, or faith,
orfantasyoughttobetotallyabsentfromtheattitudeofmindofthoseseriously
dedicatedtosearchingforthefoundationalunderpinningsofouruniverse.Nature
herself,afterall,surelyhasnoseriousinterestintheephemeralwhimsofhuman
fashion.Norshouldsciencebethoughtofasafaith,thedogmasofsciencebeing
undercontinualscrutinyandsubjecttotherigoursofexperimentalexamination,
tobeabandonedthemomentthataconvincingconflictariseswithwhatwefind
tobetheactualityofnature.Andfantasyissurelytheprovinceofcertainareasof
fictionandentertainment,whereitisnotdeemedessentialthatsignificantregard
bepaidtotherequirementsofconsistencywithobservation,ortostrictlogic,or
eventogoodcommonsense.Indeed,ifaproposedscientifictheorycanberevealed
asbeingtoomuchinfluencedbytheenslavementoffashion,bytheunquestioning
followingofanexperimentallyunsupportedfaith,orbytheromantictemptations
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