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Exploring the Global Topology of the Universe

Helio V.Fagundes

InstitutodeF

isiaTeoria,UniversidadeEstadual Paulista

S~aoPaulo,SP01405-900, Brazil

Reeivedon20Deember,2001

Wereviewtheworkdonebyourgrouponosmitopology. Itrangesfromearlyattemptstosolve

afamousontroversyaboutquasarsthroughthemultipliityofimages, toquantumosmologyin

thisontextandanappliationtoQEDrenormalization.

I Introdution

The preferred osmologial models for the

desrip-tion of the universe, exept for its very rst

in-stants, are those of Friedmann-Lema ^

itre-Robertson-Walker(FLRW), popularlyknownas`Big Bang'

mod-els. See,forexample,OhanianandRuÆni[1℄.

It isgenerallyassumed that theglobal topologyof

osmispatialsetionsissimplyonneted,thatis,they

areoneofthespherial(S 3

);Eulidean E 3

,or

hyper-boli (H 3

)spaes,whihhavepositive,null,and

nega-tiveurvature,respetively.

ButspaesE 3

andH 3

haveinniteextension. This

hasledsomepioneers,likeEinstein,Shwarzshild,and

Friedmann,toonsiderthequestionofthenitevs.

in-nite sizeoftheuniverse,anditstopology.

Beginningin1971,withapaperbyEllis[2℄,researh

on the possibility of osmi spae being nite and its

topologymultiplyonneted, hasbeendonemore

sys-tematially,ifslowlyatrst.

Today there is areasonable numberof researhers

in this area(my guessis aboutahundred worldwide),

inludinghereinBrazil.

Sine this area is still little known, in this talk I

will presentasummary of work doneby myselfand a

few ollaborators at IFT/UNESP in S~ao Paulo. The

setions thatfollowlistanumberofpublished papers,

whiharerepresentativeoftheeetofnontrivial

os-mi topologyon the topis: setion II,formal

theo-retial works; III, thequasar redshiftontroversy;IV,

tting models to data; V, osmi rystallography; VI,

quantumeldtheoryandquantumosmology;andVII,

theosmimirowavebakground.

Note that most of this researh was done before

1998, so we ould with impunity assume a null

os-II Formal theoretial works

II.1 A osmologial model with ompat spae

setionsand low massdensity[3℄.

Inthis model theadopted spaetime topologywas

M 4

=R,whereRisthetimeaxisandisthespae

setion. Thisformofspaetimeholdsforallworksited

below(withdierent's,ofourse).

Here =T

g S

1

; whereT

g

isthegenus-g surfae

andS 1

istheirle. Themetriis

ds 2

=a 2

()(d 2

d 2

sinh 2

d' 2

) b 2

()d 2

;

where

t() = a

(sinh );

a() = a

(osh 1);

b() = 3a

[oth(=2) 2℄;

witha

=onstant. This metrihad beenstudied by

KantowskiandSahs[4℄,andisoftypeIIIin the

las-siationofBianhi[5℄.

AtthetimeIwasunawareoftheexisteneof

three-dimensional losedhyperboli manifolds,and this was

thebestsubstituteI ouldndforalosedFriedmann

modelofunderritialdensity.

II.2CompatiationofFriedmann'shyperboli

model[6℄

Now is a losed hyperboli manifold onstruted

by Best[7℄. I didnotgo into thedetails ofimage

for-mation, but found that the spae of images was the

overingspaeH 3

,andthathomogeneityandisotropy

should bereinterpretedin terms ofthe distributionof

multiple images in the overing spae. I also found

that we should have the relative density of matter

0

<0:964in order thatarepeated patternof images

ouldbeobserved.

(2)

HereIestablishedaorrespondenebetweenthe

ge-ometrilassiationsofBianhiandKantowski-Sahs

(BKS) on one side, and Thurston's on the other,

a-ordingtothefollowingtable:

Thurston type BKS type

T1 BIX

T2 BI,BVII(0)

T3 BV,BVII(A> 0)

T4 KS

T5 BVI(1)

T6 BVIII

T7 BII

T8 BVI(0)

It was also found that Bianhi types IV and

VI(A); 0 < A < 1; annot be ompatied - i. e.,

there are not any losed, loally homogeneous

mani-foldsofthese Bianhitypes.

II.4 Closedspaes in osmology[9℄

This paperimproveson theprevious one,and

dis-usses thequestion of loal vs. global homogeneityof

theonstanturvaturemodels.

II.5NumerialstudyofaperturbedEinstein-de

Sitterosmologial model[10℄

Hereis the3-torusT 3

. Ourpurposewastond

howaninhomogeneityofthematterdensity,writtenas

(x;); =1 t;aetsthemetri,whihwasassumed

tohavetheform

ds 2

= 2

d 2

a 2

(x;)dx 2

b 2

(x;)(dy 2

+dz 2

);

wherea 2

(x;),b 2

(x;)reduetoa

EdS

(t)=(t=t

0 )

2=3

if

weremovetheperturbation. Theresultwasthat,fora

perturbationof ofabout 80%,themetri utuated

at most5%, in agreementwith aheuristiestimateof

Barrow[11℄

III The quasar redshift

ontro-versy

III.1Quasar-galaxyassoiationswithdisordant

redshiftsasa topologialeet. II.Alosed

hy-perboli model[12℄

isoneofBest's[7℄manifoldswitharegular

iosa-hedronasfundamentalpolyhedron (FP).Themetriis

thesameasinFriedmann'sopenmodel.

Thesearhforimagesinonjuntiontosimulatethe

ontroversialpairswasdonebyomputer,bysanning

alldiretionsthatmettheobserver. Theobtainedpairs

were notrealisti: e. g., redshifts 0.12 for the galaxy

and4.3forthequasar.

III.2Smallestuniverseofnegativeurvature[13 ℄

isthesmallestknownCHM,withnormalized

vol-ume 0.9427... and 18 faes, disovered independently

by Weeks [14℄ and by Matveev and Fomenko[15℄. It

wasassumed

0

=0:1:HereIgotbetterresultsforthe

quasar-galaxy assoiations than in the previous ase:

manyofthesimulatedpairshadrealistiredshifts,like

0.002 for thegalaxyand 1.31 forthe quasaror

quasi-stellarobjet(QSO).

However,omparisonwithBurbidgeetal.'s[16℄

at-alog of assoiations, for example, would still not be

reliable: the model parameters are arbitrary, only 31

soureswereusedinthesimulation,andofoursemany

onjuntionsareline-of-sightonidenes.

Themodelisalsointerestingonaountofthesmall

volume: multiple images would allow astronomers to

see objets at dierentepohs of their evolution; and

it hasalargerprobabilitythan alargermodel for the

spontaneousreationoftheuniverse.

IV Fitting models to data

IV.1 A searh for QSO's to t a osmologial

modelwith at, losed spatial setions[17℄

Based on a atalog with about 1500 quasars, we

lookedforpairsequidistantfromEarth,andalongthree

orthogonalaxis. wasthe3-torus,witharetangular

parallepiped as FP, whose sides were tted to 3591,

2966,and2792Mp.

IV.2 A suggestion on the pair of QSO triplets

1130+106fB,A,Cg,fX,Y,Zg[18℄

Thequasarsinthetitle aretwoalignedtriplets

dis-overed by Arp and Hazard [19℄, with similar

orre-sponding redshifts, whih are f2.1, 0.54, 1.6g for the

rst triplet, and f2.1, 0.51, 1.7g for the seond one.

TheywereadjustedtoanEinstein-deSittermodelwith

aubeofside387MpasFP,whihisanunrealistially

smallsize.

V Cosmi rystallography

V.1 Onlosed Einstein-de Sitteruniverses[20℄

Themethod of osmi rystallography(CC)

intro-dued by Lahieze-Rey et al. [21℄ was applied to a

fewmodels,allwithEinstein-deSittermetribut

vary-ing topologies. The idea was to verify that the CC

method yieldsobservable(inpriniple) results,even if

the FP'ssides are ofthe order of thehorizon's radius

R

H

= 2=H

0

, where H

0

is Hubble's onstant. Good

resultswere obtainedwiththeFP'ssidesequal0:7H

0 ;

(3)

V.2Cosmirystallographyinaompat

hyper-boli universe [22℄

andFParethesameasin[12℄. WeappliedtheCC

methodtothisgeometriallyinhomogeneousmodeland

didnotobtainanysharppeaks- asexpetedfrom the

independent works ofLehouqet al. [23℄and Gomero

et al. [24℄.

But we did get a smaller utuation that is not

present in the ontrol open osmology. We are at

presenttentativelyattributing thesesmallutuations

to typeIIpairs,asdened in[23℄.

VI Quantum eld theory and

quantum osmology

VI.1Aosmilattieasthesubstratumof

quan-tum elds[25℄

This work is a lowest-order attempt to avoid the

innitiesofquantumeletrodynamisrenormalization.

Bothongurationandmomentumspaesareassumed

tohavethetopologyofa3-torusT 3

;withubesofsides

a==H

0

=8000Mp=2:710 28

m,andP =2~=a

10 20

Gev/;respetively.

Lorentz invariane is abandoned for very large,

presentlyinaessibleenergies.

For harge and mass renormalization at the

one-loop order, I got Z

3

= 0:925, e = p

Z

3 e

0

= 0:962e

0 ;

m=1:185m

0 ;andZ

2

=1:160,inthenotationof

Itzyk-sonandZuber[26℄.

VI.2 Casimir energy in a small volume,

multi-ply onneted,stati hyperboli preinationary

universe[27℄

ThisworkwasorallyommuniatedatthisMeeting,

andappearselsewherein theseProeedings.

VI.3 Birth ofa losed universe of negative

spa-tial urvature [28℄;On the birthof a losed

hy-perboli universe[29℄

is the rst the lens spae L(50;1), then Weeks

manifoldasin[13℄.

Starting with the spontaneous reation, from a

spherialorbifold,ofadeSitteruniversewiththe

topol-ogy ofalens spae,weproeeded asDe Loreniet al.

[30℄, to obtain a quantum topology hange into a de

Sitter universe with Weeks manifold asspae setion.

Afterinationitbeomesalosedhyperboliuniverse,

withthemetriofanopenFLRWuniverse.

VII The osmi mirowave

bak-ground radiation

VII.1 The quadrupole omponent of the reli

model[31℄

This was an appliation of the model in [3℄ to a

quadrupole moment of the osmi mirowave

bak-groundreported by Fabbri and Melhiorri[32℄.

Com-paringtheobtainedrelation

1+Z= a(

observ )

a(

emission )

(1 "os 2

observ )

with the result of [32℄, I obtained " = 4Q=2:7K =

0:0013;

0

=1 3"=2=0:998:

VII.2 Fitting hyperboli universes to Cay

on-Smoot spots in COBE maps[33℄; Soures of

CMB spots in losed hyperboli universes [34℄

Cayon and Smoot [35℄ identied several spots in

NASA'ssatelliteCOBE'smapsoftheosmimirowave

bakground as physial (rather than noise), hene as

smallutuationsofthematterdensity.

InthesepapersIsimulatedtheposition ofsixold

andeighthotCSspotsin losedhyperboli manifolds,

and interpreted them as having evolved into today's

galaxysuperlustersandgalaxyvoids,respetively.

Present atalogs [36℄ only list superlusters up to

Z = 0:12, whih is ompletely inadequate for at of

thesimulatedmodels: typially,inoneofthelatterthe

14redshiftsareintherange0:361to1:370.

I thank the Brazilian ageny CNPq for partial

-nanialsupport.

Referenes

[1℄ H.Ohanian and R.RuÆni,Gravitation andSpaetime

(W.W.Norton,New York,1994),Chapter9.

[2℄ G.F.R.Ellis,Gen.Relat.Grav.2,7(1971).

[3℄ H.V.Fagundes,Lett.Math.Phys.6,417(1982).

[4℄ R.Kantowski and R. K.Sahs, J. Math. Phys.7, 443

(1966).

[5℄ L.Bianhi,Mem.Mat.Fis.So.Ital.Si.11,267(1898).

[6℄ H.V.Fagundes,Phys.Rev.Lett.51,517(1983).

[7℄ L.A.Best,Can.J.Math.23,451(1971).

[8℄ H.V.Fagundes,Phys.Rev.Lett.54,1200 (1985).

[9℄ H.V.Fagundes,Gen.Relat.Grav.24,199(1992);

Ad-denduminGen.Relat.Grav.30,1437(1998).

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337(1991).

[11℄ J.D.Barrow,Quart.J.Roy.Astr.So.30,163(1989).

[12℄ H.V.Fagundes,Astrophys.J.338,615(1989);Errata

(4)

[14℄ J. R. Weeks, Ph. D. Thesis, Prineton University

(1985);SnapPea: Aomputerprogram forreatingand

studying three-manifols, freely available from the site

www.northnet.org/weeks.

[15℄ S.V.MatveevandA.T.Fomenko,RussianMath.

Sur-veys43,3(1988).

[16℄ G. Burbidge, A. Hewitt, J. V. Narlikar, and P. Das

Gupta,Astrophys.J.(Suppl.)74,675(1990).

[17℄ H.V.FagundesandU.F.Wihoski,Astrophy.J.322,

L5(1987).

[18℄ H. V. Fagundes, Rev. Mex. Astron. Astrof. 21, 79

(1990).

[19℄ H.ArpandC.Hazard,Astrophys.J.240,726(1980).

[20℄ H.V.FagundesandE.Gausmann,Phys.Lett. A238,

235(1998).

[21℄ M. Lahieze-Rey, J.-P. Luminet, and J.-P. Uzan,

As-tron.Astrophys.313,339(1996).

[22℄ H. V. Fagundes and E. Gausmann,Pro. XIX Texas

Symp. Relat. Astrophys. Cosmol. (Paris, 1998), Nul.

Phys.B(Pro.Suppl.)80,CD-ROM.

[23℄ R. Lehouq, J.-P. Luminet, and J.-P. Uzan, Astron.

Astroph.344,735(1999).

[24℄ G. Gomero, A. F. Teixeira, M. Rebouas, and A.

Bernui,preprintgr-q/9811038(1998).

[25℄ H.Fagundes,Rev.Bras.F

is.(nowBraz.J.Phys.)19,

[26℄ C. Itzykson and J.-B. Zuber, Quantum Field Theory

(Addison-Wesley,NewYork,1980),Chapter7.

[27℄ D.Muller,H.V.Fagundes,andR.Opher,Phys.Rev.

D63,123508(2001).

[28℄ S.S.e Costa and H.V. Fagundes, Gen. Relat.Grav.

30,863(1999).

[29℄ S.S.e Costa and H.V. Fagundes, Gen. Relat.Grav.

33,1489(2001).

[30℄ V.A.DeLoreni,J.Martin,N.Pinto-Neto,andI.D.

Soares,Phys.Rev.D56,3329(1997).

[31℄ H. V. Fagundes, Astrophys. Lett. (now Astrophys.

Lett.Comm.)23,161(1983).

[32℄ R.FabbriandF.Melhiorri,Gen.Relat.Grav.13,201

(1981).

[33℄ H.V.Fagundes,Astrophys.J.470,494(1996).

[34℄ H.V.Fagundes,preprintastro-ph/0007443;toappear

inPro.IXMarelGrossmannMeetingonGeneral

Rel-ativity,eds.R.T.Jantzen,V.Gurzadyan,andR.RuÆni

(WorldSienti,Singapore,2002).

[35℄ L.CayonandG.Smoot,Astrophys.J.452,494(1996).

[36℄ M. Einasto, E. Tago, J. Jaaniste, J. Einasto, and H.

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