Chuong 7 Vu Tru Trong Vo Hat de - Smith.N Studio

8/3/2019 Chuong 7 Vu Tru Trong Vo Hat de - Smith.N Studio

1/29

Trang 173Ngi dch: [email protected]; http://datrach.blogspot.com

CHNG 7TH GII MNG

Chng ta sng trn mt mng hay chng ta ch l mt nh a chiu?

Smith Nguyen Studio.


2/29

V T R T R O N G M T V H T

Trang 174 Ngi dch: [email protected]; http://datrach.blogspot.com

(Hnh 7.1)

Thuyt-M ging nh mt tmhnh ghp. Ta c th d dng nhnra v xp cc mu phn binca n nhng chng ta khng bitnhiu v nhng g xy ra phngia, chng ta khng th lygn ng v cc i lng cgi tr rt nh.



3/29

T H G I I M N G


Chuyn du hnh khm ph ca chng ta trong tng lai stip tc nh th no? Chng ta s thnh cng trong vic truylng mt l thuyt thng nht hon ton iu khin v tr

ny v mi th trong hay khng? Thc ra, nh m t trongchng 2, chng ta c th ng nht L thuyt v vn vt (Theoryof Everything ToE) l l thuyt-M. L thuyt ny khng c mtm t n nht, t nht l vi hiu bit ca chng ta hin nay. Thayvo , chng ta tm thy mt mng li cc l thuyt khc hnnhau. Tt c cc l thuyt dng nh l cc l thuyt gn ngtheo cc gii hn khc nhau ca cng mt l thuyt c bn ngsau ging nh l thuyt hp dn ca Newton l mt l thuytgn ng ca l thuyt tng i rng ca Einstein trong gii hntrng hp dn yu. Thuyt-M ging nh mt tr chi ghp hnh:vic nhn dng v xp cc mu ra ca tm hnh l d nht. Raca tm hnh tng ng vi cc gii hn ca thuyt-M trong mt s cc i lng c gi tr nh. By gi chng ta c mt khinim tng i tt v cc ra ny nhng vn c mt khong trng tm ca tm hnh thuyt-M, , chng ta khng bit iu g angxy ra (hnh 7.1). Chng ta khng th ni l chng ta tm ra Lthuyt v vn vt cho n khi chng ta lp y kho ny.

Ci g tm ca thuyt-M? Chng ta s tm thy mt con rng(hoc mt ci g cng k l nh th) ging nh trn cc bn c v cc vng t cha c khm ph? Kinh nghim ca chng tatrong qu kh cho thy c th chng ta tm thy cc hin tng mikhng nh trng i khi chng ta m rng tm quan st vo cc ncthang nh hn. Vo u th k hai mi, chng ta hiu qu trnhvn hnh ca t nhin trn nc thang vt l c in, n ng nt khong cch gia cc thin cu cho n khong mt phn trmmili mt. Vt l c in gi thit rng vt cht l mt mi trng

Kiu IIB

Kiu I Kiu IIA

Heterotic-0 Heterotic-E

Siu hp dn 11 chiu



4/29



lin tc vi cc tnh cht nh l do v nht, nhng cc bngchng bt u xut hin cho thy rng vt cht khng lin tc mgin on: chng c to thnh t nhng n v nh ly ti c gil nguyn t. T nguyn t bt ngun t ting Hy Lp v c nghal khng th phn chia, nhng ngay sau ngi ta thy rng ccnguyn t bao gm cc in t quay xung quanh ht nhn c tothnh t proton v neutron (hnh 7.2).

Nghin cu v vt l nguyn t trong ba mi nm u ca th ktrc cho chng ta hiu bit n di mt phn triu mili mt. Sau chng ta pht hin ra rng proton v neutron c to thnh tcc ht cn nh hn c gi l quark (hnh 7.3).

Cc nghin cu gn y ca chng ta v vt l ht nhn v vt lnng lng cao dn chng ta ti cc nc thang cn nh hn mtphn t mili mt. Dng nh chng ta c th tip tc mi mi, phthin ra cc cu trc trn cc nc thang nh hn v nh hn. Tuynhin, c mt gii hn cho ci chui ny ging nh c mt gii hncho cc con bp b lng trong nhau ca ngi Nga (hnh 7.4).

Cui cng, khi ta cm n con bp b nh nht, n khng c tothnh t con no khc na. Trong vt l, con bp b nh nht c gi l di Plank. Vic d n cc khong cch ngn hni hi cc ht c nng lng cao ging cc ht trong cc h en.Chng ta khng bit chnh xc di Plank c bn trong thuyt-M,nhng c th n ch b bng mt mili mt c chia thnh mt trmngn t t t ln. Chng ta s khng c nh xy cc my gia tcht c th d n cc di nh nh th. Chng phi ln hn h mt

(Hnh 7.2)

Hnh th nht bn phi: M hnhnguyn t v hnh c inHnh th hai bn phi: Nguyn tvi cc in t quay xung quanhht nhn c to thnh t ccneutron v proton.

(Hnh 7.3)

Trn: Mt proton gm c haiquark thun (mi mt quark cin tch bng hai phn ba) vmt quark nghch (mi mt quarkc in tch bng m mt phnba). Di: Mt neutron gm haiquark nghch (mi mt quark cin tch bng m mt phn ba)v mt quark thun (mi mtquark c in tch bng hai phnba).



5/29

T H G I I M N G


Vt l c in

Vt l ht nhn

Vt l nguyn t

L thuyt thngnht ln

di Plank: Thuyt-M?

0,00000000000000000000000000000000001616 mm

(Hnh 7.4) Mi con bp b i din cho mt m hnh l thuyt v t nhin cho nmt gii hn nht nh. Mi mt con li gm mt con khc nh hn tng ng vimt l thuyt m t t nhin ti cc khong cch ngn hn. Nhng trong vt l, cmt di c bn nh nht, l di Plank, ti cc khong cch , t nhin cth c biu din bng thuyt-M.



6/29



tri v chc chn l chng khng c thng qua trong bi cnh tichnh hin nay (hnh 7.5).

Tuy nhin, c mt bc pht trin mi rt th v cho php chngta c th khm ph mt cch d dng hn (v r hn) t nht mtvi con rng ca thuyt-M. Nh gii thch trong chng 2 v 3,trong mng li cc m hnh ton hc ca thuyt-M, khng thigian c mi hoc mi mt chiu. Cho n gn y ngi ta vnngh l su hoc by chiu b sung b cun li rt nh. N ging nh

si tc ca con ngi (hnh 7.6).

Nu bn nhn vo mt si tc di mt ci knh lp, bn c th thyn c mt dy, nhng di mt thng, n ging nh mt ngch c di m khng c cc chiu khc. Khng thi gian c thtng t nh th: trn nc thang kch thc con ngi, nguyn thoc thm ch ht nhn, khng thi gian ging nh l c bn chiuv gn nh phng. Mt khc nu chng ta d ti cc khong cchrt ngn s dng cc ht nng lng cc cao, chng ta c th thykhng thi gian l mi hoc mi mt chiu.

(Hnh 7.5)

Kch thc ca mt my gia tc c th thm d cc khongcch nh nh di Plank c thln hn ng knh ca h mttri.



7/29

T H G I I M N G


Khi my d c nng lng cao, chng c th tit lkhng thi gian l a chiu

(Hnh 7.6)

Di mt thng th mt si tc ging nh mt ng vimt chiu. Tng t nh th, vi chng ta, khng thi gianc v nh l bn chiu nhng chng s l mi hay mimt chiu khi d bng cc ht nng lng rt cao.



8/29



Nu cc chiu b sung ny rt nh th rt kh c th quan st cchng. Tuy vy, gn y c gi rng c mt hoc nhiu hn mtchiu c th kh ln hoc thm ch l v hn. tng ny l mtli th rt ln (ch t l i vi mt ngi theo ch ngha thc chngnh ti) l n c th c kim nghim bng th h tip theo cacc my gia tc ht hoc bng cc php o lc hp dn tm ngnrt nhy. Cc php o nh vy c th tha mn c l thuyt hoc l

khng nh bng thc nghim s tn ti ca cc chiu khc.

Cc chiu b sung ln l mt bc pht trin mi th v trongnghin cu ca chng ta v m hnh hay l thuyt cui cng. Ccchiu ng rng chng ta ang sng trong mt th gii mng(brane world), mt mt phng hay mt mng bn chiu trong mtkhng thi gian c s chiu nhiu hn th.

Vt cht v cc lc phi hp dn nh l lc in t b gii hn trnmng ny. Do , tt c ngoi tr hp dn hnh x nh l chng

(Hnh 7.7) TH GII MNG

Lc in b gii hn trn mngv n s suy gim vi mt tc va phi cc in t c ccqu o n nh xung quanh htnhn ca cc nguyn t.



9/29

T H G I I M N G


trong bn chiu. c bit l lc in gia ht nhn ca nguyn tv in t quay xung quanh n s gim nhanh theo khong cch vimt tc va phi cc nguyn t n nh khng cho in t rivo ht nhn (hnh 7.7).

iu ny ph hp vi nguyn l v nhn l v tr cn phi ph hpcho sinh vt c tr tu: nu nguyn t khng n nh th chng ta

khng th y quan st v tr v hi ti sao n li th hin bnchiu.

Mt khc, hp dn trong hnh dng khng thi gian cong s thmvo ton b khng thi gian vi nhiu chiu hn. iu ny c nghal hp dn s hnh x khc hn vi cc lc khc m chng ta tringhim: v hp dn c th lan truyn theo cc chiu b sung nn ns suy gim theo khong cch nhanh hn l ta trng i (hnh 7.8).

Nu s suy gim nhanh ca lc hp dn m rng n khong cch

(Hnh 7.8)

Hp dn tri rng theo cc chiub sung v c tc ng dc trnmng v s suy gim theo khongcch nhanh hn l s suy gimkhi hp dn trong khng thigian c bn chiu.



10/29



(a)

(b)

v tr th chng ta s thy cc hiu ng ca n trn qu o ca cchnh tinh. Thc ra cc qu o s khng bn v nh nhn xt chng 3: cc hnh tinh hoc l s ri vo mt tri hoc l s thotvo khong khng ti tm lnh lo gia cc v sao (hnh 7.9).

Tuy nhin iu ny s khng xy ra nu cc chiu b sung kt thctrn mt mng khc khng qu xa mng m chng ta ang sng.Th th vi cc khong cch ln hn khong cch gia cc mng thhp dn khng th lan truyn mt cch t do m thc s b gii hnvo mt phng ging nh lc in v suy gim vi mt tc va phi cc hnh tinh quay quanh mt tri (hnh 7.10).

Mt khc, i vi cc khong cch nh hn khong cch gia ccmng, hp dn suy gim nhanh hn rt nhiu. Lc hp dn rt nhgia cc vt nng c o mt cch chnh xc trong phng th

(Hnh 7.9)

Lc hp dn suy gim theokhong cch nhanh hn th quo ca cc hnh tinh s bt nnh. Cc hnh tinh hoc l s ri

vo mt tri (a) hoc l s thotkhi sc ht ca mt tri (b).



11/29

T H G I I M N G


(Hnh 7.10) Mt mng th hai gn th gii mng s lm cho lc hp dn khng lan xatheo cc chiu b sung, iu c ngha l ti cc khong cch ln hn khong cc mng,lc hp dn s suy gim vi mt tc m ta mong i cho trng hp bn chiu.

Cc chiu b sung



12/29



nghim nhng cho n nay cc thc nghim vn cha quan stc cc hiu ng ca cc mng phn cch nhau mt khong nhhn mt vi mili mt (hnh 7.11).

Trong cc mng v tr ny, chng ta ang sng trn mt mngnhng c l l c mt mng bng (shadow) khc gn mng cachng ta. V nh sng b gii hn trn cc mng v khng th lantruyn xuyn qua khong cch gia chng nn chng ta khng thnhn thy v tr bng . Nhng chng ta c th cm thy nhhng hp dn ca vt cht ln mng bng. Trong mng ca chngta, ta thy cc lc hp dn nh th c to ra bi cc ngun thcs ti m ch c mt cch duy nht bit c n l thng qua hpdn ca chng (hnh 7.12). Thc ra gii thch tc quay ca ccv sao xung quanh tm ca di ngn h th xem ra cn phi c mtlng vt cht nhiu hn vt cht m chng ta quan st thy.

(Hnh 7.11)TH NGHIM CAVENDISH

Mt chm laser (e) xc nh btk s xon ca cnh tay n (b)v n c chiu ln mn hnh o(f). Hai qu cu ch nh (a) gnvo hai bn cnh tay n (b). Trncnh tay n c mt ci gng

nh (c) v cnh tay n c treot do bng mt si dy xon (d).Hai qu cu ch ln (g) gn vinhau bng mt thanh cn bng cth quay c v chng c tgn hai qu cu ch nh. Khi haiqu cu ch ln quay ti v tr idin th cnh tay n (b) s thitlp mt v tr mi.



13/29

T H G I I M N G


(Hnh 7.12) Trong kch bn th gii mng, cc hnh tinh c th quay xung quanh mt khilng ti trn mng bng v lc hp dn lan theo cc chiu b sung.



14/29



VNTCQUAY(KM/S)

Bn knh (kpc)

THIN H XOY C NGC 3198

ALBADA & SANCISI 1986

NGC 3198

BNG CHNG V VT CHT TI

Rt nhiu cc quan st v tr khc nhau gi rng, trong thin h ca chng ta v trongcc thin h khc, vt cht nhiu hn chng tanhn thy rt nhiu. Quan st thuyt phc nht lcc ngi sao ngoi ra cc thin h xoy c nh Ngn h ca chng ta quay qu nhanh, nu chnhng ngi sao m chng ta nhn thy th khngth gi chng trn cc qu o c (xem hnh

bn).T nhng nm 1970, chng ta thy c mt schnh lch gia vn tc quay ca cc ngi sao vng ra ca cc thin h hnh xoy c (biu dinbng cc ng chm trn gin ) v vn tcquay theo cc nh lut chuyn ng ca Newtonvi s phn b ca cc ngi sao kh kin trongthin h (ng cong lin nt trn gin ). Schnh lch ny cho thy cn phi c nhiu vt chthn cc vng bin ca cc thin h xoy c.



15/29

T H G I I M N G


BN CHT CA VT CHT TI

Ngy nay, cc nh v tr hc tin rng phn tm cacc thin h xoy c ch yu gm vt cht thng,nhng phn bin ca chng li ch yu gm vtcht ti m chng ta khng th nhn chng mt

cch trc tip. Nhng mt trong nhng vn quantrng nht l tm ra bn cht ca vt cht ti thngtr vng bin ca cc thin h. Trc nhng nm1980, ngi ta cho rng vt cht ti ny cng l vtcht thng to thnh t proton, neutron v int nhng dng khng th quan st c: c thl cc m my kh, hoc cc vt th c c nng

khng pht sng MACHO (massive compact haloobject) nh l cc sao ln trng, sao neutron, hocthm ch l cc h en.Tuy nhin, cc nghin cu gn y v s hnhthnh cc thin h lm cho cc nh v tr hctin rng mt phn ng k ca vt cht ti cn phi

dng khc vt cht thng. C th xut hin tkhi lng ca cc ht rt nh nh l cc ht axionhoc neutrino. Chng cn c th gm cc thc thk l hn nh l cc ht nng tng tc yu WIMP(weakly interacting massive particle) tin on tcc l thuyt ht c bn hin i, nhng ta vn chathu c t thc nghim.



16/29



Khi lng thiu ht c th l do c mt s loi ht k l trongth gii ca chng ta nh l cc ht nng tng tc yu (weaklyinteracting massive particles WIMP) hoc l cc ht axion (mtloi ht c bn rt nh). Nhng khi lng thiu ht ny c th lbng chng v s tn ti ca v tr bng vi vt cht trong . Cth trong v tr c loi ngi cn ngh bn khon v khi lngdng nh b thiu ht trong v tr ca h gii thch qu o cacc ngi sao bng xung quanh tm ca thin h bng (hnh 7.13).

(Hnh 7.13)C th chng ta khng nhn thythin h bng trn mt mng bngv nh sng khng th truyn theocc chiu b sung. Nhng lc hpdn th c th lan theo cc chiu, do , qu trnh quay ca thinh chng ta c th b nh hngbi vt cht ti m ta khng nhnthy c.

Th gii vi chiu b sung ca con ngi khng th nm gia cc mng.



17/29

T H G I I M N G


Thay cho vic cc chiu b sung kt thc trn mt mng th hai,mt kh nng khc l cc chiu l v hn nhng b un rt congnh mt ci yn nga (hnh 7.14). Lisa Randall v Raman Sundrumchng minh rng kiu cong th ny s hot ng kh ging mtmng th hai: nh hng hp dn ca mt vt th trn mng bgii hn trong mt ln cn nh ca mng v khng lan truyn nv tn theo cc chiu b sung. Trong m hnh mng bng, trng

hp dn suy gim theo khong cch kh ln gii thch qu oca cc hnh tinh v cc th nghim lc hp dn trong phng thnghim, nhng lc hp dn li thay i nhanh hn ti cc khongcch ngn.

Tuy nhin, c mt s khc bit quan trng gia m hnh Randall-Sundrum v m hnh mng bng. Cc vt th chuyn ng di nhhng ca lc hp dn s to ra mt sng hp dn, nhng gn sngca cong lan truyn trong khng thi gian vi tc nh sng.

(Hnh 7.14)

Trong m hnh Randall-Sun-drum, ch c mt mng (th hintrong hnh ch vi mt chiu).Cc chiu b sung m rng nv hn nhng chng b un cong

nh mt chic yn nga. congny lm cho trng hp dn cavt cht trn mng khng lan xatheo cc chiu b sung.

n tuyn ca th giimng ca chng ta



18/29



S

THAY

ICACHUKQUAY

CAPSR1913+16TNM1

975

th ca pulsari PSR 1913+16t nm 1975

Hai sao neutron ang tin lign nhau theo hnh xoy c

CHM SAO PULSAR IThuyt tng i rng tin on rng cc vt thnng chuyn ng di nh hng ca trng hp

dn s pht ra cc sng hp dn. Ging nh sngnh sng, cc sng hp dn cng mang nng lngkhi vt th pht ra chng. Nhng tc mt nnglng rt yu v rt kh quan st. V d, vic phtra sng hp dn s lm cho tri t dn dn ri vomt tri theo hnh xoy c, nhng qu trnh phimt n 1027 nm. Nhng vo nm 1975, Russell Hulse v Jo-seph Taylor pht hin ra chm sao pulsar i

PSR1913+16. y l mt h gm hai ngi saoneutron quay xung quanh nhau vi khong cchga chng ch bng ng knh ca mt tri. Theo

thuyt tng i rng, chuyn ng nhanh c nghal chu k quay ca h ny s gim nhanh hn rtnhiu v phi pht ra sng hp dn rt mnh. Sthay i tin on t thuyt tng i rng phhp tuyt vi vi cc quan st rt cn thn caHulse v Taylor v cc thng s chuyn ng. Ccthng s ny cho thy t nm 1975 chu k quay gim i 10 giy. Nm 1993, h t gii Nobel vtl v vic khng nh thuyt tng i.



19/29

T H G I I M N G


Ging nh sng in t nh sng, sng hp dn cng mang nnglng, mt tin on c khng nh bng cc quan st t chmpulsar i PRS1913+16.

Nu thc s chng ta ang sng trn mt mng trong mt khnggian c cc chiu b sung th cc sng hp dn c to bi cc vtth chuyn ng trn mng s truyn sang cc chiu khc. Nu cmt mng bng th hai th cc sng hp dn c th b phn x trli v b by gia hai mng. Mt khc nu ch c mt mng n nhtv cc chiu b sung tri di mi mi nh trong m hnh Randall-Sundrum th sng hp dn c th cng thot i v mang nng lngi khi mng v tr ca chng ta (hnh 7.15).

(Hnh 7.15)

Trong m hnh Randall-Sundrum,

cc sng hp dn bc sng ngnc th mang nng lng ra khingun pht nm trn mng lmcho nh lut bo ton nng lngb vi phm.



20/29



iu ny c v vi phm mt trong nhng nguyn l cn bn cavt l: nh lut bo ton nng lng. Tng nng lng lun lunkhng i. Tuy nhin s vi phm ch xut hin v tm nhn cachng ta v ci ang xy ra b gii hn vo mng. Mt thin thn cth nhn thy cc chiu b sung v c th bit nng lng vn khngi m ch lan truyn i ra xa m thi.

Cc sng hp dn to bi hai ngi sao quay quanh nhau c bcsng di hn rt nhiu ng knh ca cong hnh yn nga trong

cc chiu b sung. iu ny c ngha l cc sng hp dn c chiuhng b giam trong mt ln cn nh ca mng ging lc hp dn v khng th lan truyn ra xa vo cc chiu b sung hoc khngth mang nng lng ra khi mng. Mt khc, cc sng hp dn cbc sng ngn hn ln m cc chiu b sung b cun li s ddng thot ra khi ln cn ca mng.

Ngun duy nht c th pht ra mt lng ng k cc sng hp dnc bc sng ngn c th l cc h en. Mt h en trn mng sko di n mt h en theo cc chiu khc. Nu h en nhth n gn nh c hnh trn; tc l n vn ti nhng khong cchtrong cc chiu b sung bng kch thc ca n trn mng. Mtkhc, mt h en ln trn mng s ko di thnh mt chic bnhdt, tc l n b gii hn trong mt ln cn ca mng v chiu dy(theo cc chiu b sung) nh hn rt nhiu so vi chiu rng (trnmng) (hnh 7.16).

Nh gii thch trong chng 4, thuyt lng t ni rng cc hen khng phi l hon ton en: chng s pht ra tt c cc loiht v bc x ging nh cc vt nng. Cc ht cc nh sng tabc x (radiation-like light) s c pht ra dc theo mng v vtcht v cc lc phi hp dn nh l lc in t s b gii hn trongmng. Tuy nhin, cc h en cn pht ra sng hp dn. Cc sngny khng b gii hn trong mng m cn c th lan truyn theo ccchiu b sung na. Nu h en m ln v c dng chic bnh dt,cc sng hp dn s gn mng. iu ny c ngha l cc h ens mt nng lng (v do mt c khi lng do phng trnhE=mc2) vi mt tc cn thit trong khng thi gian bn chiu.Vy nn cc h en s bay hi chm chp v gim kch thc chon khi nh hn bn knh ca cong ca cc chiu b sung hnh



21/29

T H G I I M N G


yn nga. Ti thi im ny cc sng hp dn thot ra t h en bt u t do thot vo cc chiu b sung. i vi mt ngi trnmng th cc h en hay l cc ngi sao ti nh Michell gi (xemchng 4) s pht ra cc bc x ti, cc bc x ny khng th quanst trc tip t mng nhng s tn ti ca n c th c suy ra tvic cc h en mt i khi lng.

(Hnh 7.16)

Mt h en trong v tr cachng ta nm trn mng s mrng theo cc chiu b sung. Nuh en nh th n gn nh cdng hnh trn, nhng h en lnhn trn mng s n ra thnh mth en c hnh chic bnh trongcc chiu b sung.



22/29



(Hnh 7.17) S hnh thnh th gii mng c th ging nh s hnh thnh cc bt kh trong nc si.



23/29

T H G I I M N G


iu c ngha l s bng pht bc x cui cng t cc h enang bay hi s km mnh m. iu ny c th gii thch ti saochng ta khng quan st thy cc t bng pht ca cc tia gammam c th m t cc h en ang cht mc d c mt li gii thchkhc d hiu hn l khng c nhiu cc h en vi khi lng thp bay hi ht trong mt thi gian bng tui ca v tr chon gi.

Bc x t cc h en trn mng v tr xut pht t cc thng ginglng t ca cc ht nm trn v khng phi nm trn mt mng

m nhiu mng, ging nh tt c cc th khc trong v tr u phichu cc thng ging lng t. iu ny c th lm cho cc mngxut hin v bin mt mt cch t pht. S hnh thnh lng tca cc mng hi ging s hnh thnh cc bt kh trong nc si.Nc dng lng bao gm hng t t phn t H

2O b gi li vi nhau

bng cc tng tc gia cc phn t gn nhau nht. Khi nc bun nng, cc phn t chuyn ng nhanh hn v b m vo nhau.Thng th cc va chm ny lm cho cc phn t c vn tc cao nmc mt nhm cc phn t c th thot khi lc lin kt gia chngv hnh thnh cc bt kh trong nc. Cc bt ny s to ln hay nh

i mt cch ngu nhin khi c thm cc phn t cht lng tham giavo bt kh hoc ngc li. Phn ln cc bt kh nh s b ph vvo cht lng nhng mt s bt kh pht trin ti mt kch thc tihn nht nh m nu ln hn n th bt kh s tip tc ln ln. chnh l cc bt kh m ta thy trong nc ang si (hnh 7.17).

Cc mng v tr cng tng t nh vy. Nguyn l bt nh chophp cc mng v tr xut hin t chn khng ging nh cc btkh, b mt ca bt kh tng t nh mng v trong lng bt khtng t nh cc chiu bc cao hn. Cc mng rt nh c xu hng

b bin mt, nhng mt mng m nh cc thng ging lng tpht trin ln hn mt kch thc ti hn nht nh s tip tc phttrin. Nhng ngi ging nh chng ta sng trn mng trn bmt ca bt kh, s ngh rng v tr ang gin n. N gingnh vic v cc thin h ln b mt mt qu bngv thi n ln. Cc thin h s chuyn ng ra xanhau nhng khng mt thin h no c chn ltrung tm ca s gin n. Chng ta hy vng rngs khng c ai dng mt ci kim v tr chcvo bt kh !



24/29



Theo gi thuyt khng bin nh m t trong chng 3, th shnh thnh t pht ca mng v tr c mt lch s trong thi giano ging nh mt v ht: tc l n l mt hnh cu bn chiu, gingb mt tri t nhng c thm hai chiu na. S khc nhau quantrng l v ht c m t trong chng 3, v c bn l trngrng: hnh cu bn chiu khng l b mt ca ci g khc c v su

hoc by chiu ca khng thi gian b sung m thuyt-M tin onb cun li cn nh hn ci v ht. Tuy vy, trn bc tranh v mngv tr mi th ci v ht li b lp y: lch s trong thi gian o camng m trn chng ta sng s l mt hnh cu bn chiu, hnhcu bn chiu ny l bin ca bt kh nm chiu vi nm hoc suchiu cn li b cun li rt nh (hnh 7.18).

Lch s ca mng trong thi gian o s xc nh lch s ca n trongthi gian thc. Trong thi gian thc, mng gin n theo cch lmpht tng dn nh m t trong chng 3. Mt v ht trn v trn

hon ho s l lch s kh d nht ca bt kh trong thi gian o. Tuynhin, n tng ng vi mt mng gin n mi mi theo cch lmpht trong thi gian thc. Cc thin h s khng c hnh thnhtrn cc mng nh th v do cc cuc sng tr tu cng khngth pht trin. Mt khc, cc lch s trong thi gian o khng trn vtrn mt cch hon ho c xc xut thp hn nhng li tng ngvi cc tnh cht trong thi gian thc m trong , ban u mngc cc giai on gin n lm pht tng dn nhng sau chm dn.Trong qu trnh chm dn ny, cc thin h gin n c th c hnhthnh v cc sinh vt c tr tu pht trin. Do , theo nguyn l vnhn m t trong chng 3, ch c cc v ht hi sn si mi ccc sinh vt c tr tu ang bn khon v ngun gc ca v tr tisao li khng trn tru hon ho nhn thy m thi.

V mng ang gin n nn th tch ca khng gian ca cc chiu caohn bn trong tng ln. Thm ch c th c mt bt kh khng l bncnh mng m chng ta ang sng. Nhng c tht chng ta angsng trn mt mng hay khng? Da trn tng v nh a chium t trong chng 2, thng tin v nhng s kin ang xy ra trongmt vng khng thi gian c th c m ha trn bin ca n. Do



25/29

T H G I I M N G


(Hnh 7.18)

Bc tranh th gii mng ca ngun gc v tr khc vi bc tranh trongchng 3, bi v, hnh cu hay v ht bn chiu hi b dt khng cn trngrng na m b lp y bi mt chiu th nm.

Hnh cu rng

Hnh cu c



26/29



NH A CHIU

nh a chiu gii m thngtin trong mt vng khng gianln mt b mt m b mt nyc t hn vng khng gian mt chiu. y dng nh lmt tnh cht ca lc hp dnv din tch ca chn tri skin o s cc trng thi nica h en. Trong m hnhth gii mng, nh a chiu cth l mt s tng ng mt-mt gia cc trng thi trongmt th gii bn chiu v cctrng thi trong mt th giic nhiu chiu hn. Trn quanim thc chng, ta khng phn bit c m hnh noc bn hn.

, chng ta c th ngh rng chng ta ang sng trn mtth gii bn chiu v chng ta l ci bng in ln mng

nh nhng s kin ang xy ra trong lng mt bt kh.Tuy nhin, trn quan im thc chng, ta khng thhi: thc ti l g, l mng hay bt kh? C hai khinim ch l cc m hnh ton hc m t nhng iu

m chng ta quan st. Chng ta hon ton t do s dng m hnhtin li nht. Ci g bn ngoi mng? C mt vi kh nng c thxy ra (hnh 7.19):



27/29

T H G I I M N G


1. C th chng c g bn ngoi c. Mc d bt kh c nc xungquanh, nhng ch l mt s mng tng gip chng ta hnhdung v ngun gc ca v tr. Ta c th tng tng mt m hnhton hc ch c mt ci mng v mt khong khng gian nhiuchiu hn bn trong nhng hon ton khng c g bn ngoi n c,ngay c chn khng. Ta c th tnh c nhng iu m m hnhton hc tin on m khng cn phi m ch n nhng th bnngoi.

2. Ta cng c th c mt m hnh ton hc m bn ngoi ca btkh c rt nhiu bt kh tng t. M hnh ny thc s tng ngv mt ton hc vi kh nng v chng c g ngoi bt kh ctho lun trong phn trn nhng c mt s khc nhau v tm l:con ngi cm thy hnh phc hn khi thy mnh l trung tm cakhng thi gian hn l trn ra ca n; nhng i vi mt nh thcchng th kh nng 1 v 2 l tng ng.

3. Bt kh c th gin n vo khng gian, m khng gian ny khngphi l mt hnh nh th yu ca cc s kin bn trong bt kh. Khnng ny khc hai kh nng trn v n ging trng hp nc sihn. Cc bt khc c th c hnh thnh v gin n. Nu chng vachm v kt hp vi bt kh m chng ta ang sng th kt qu rtth thm. C gi thuyt ni rng bn thn v n ln c th c tora khi cc mng va chm vi nhau.

M hnh mng v tr nh th ang l cc im nng trong nghincu. Chng mang tnh t bin rt cao nhng chng li i hi ccloi tnh cht mi cn c kim tra bng thc nghim. Chng cth gii thch ti sao hp dn c v yu n th. Hp dn c th khmnh trong l thuyt c bn nhng s lan truyn ca lc hp dnra cc chiu b sung, c ngha l n s yu ti cc khong cch lntrn mng m chng ta ang sng.

Mt h qu ca iu ny chnh l di Plank, khong cch nhnht m chng ta c th d c m khng cn to ra mt h en,ln hn kh nhiu gi tr m n cn c t yu ca hp dn trongmng bn chiu ca chng ta. Con bp b Nga nh nht ny rtcuc s khng qu nh v c th nm trong tm vi ca cc my giatc ht trong tng lai. Trn thc t, chng ta c th pht hin ra

(Hnh 7.19)

1. Mt mng/bt kh vi mtkhng thi gian nhiu chiu hnv xung quanh n khng c gkhc.

Ging nhau

2. Mt kh nng l bn ngoi mtmng/bt kh c s lin quan nbt kh khc.

3. Mt mng/bt kh gin ntrong khng gian m khng gianny khng phi l nh gngca nhng g xy ra trong lngn. Cc bt kh khc c th hnhthnh v gin n theo mt kchbn nh th.



28/29



con bp b nh nht ri, di Plank c bn, nu Hoa K khngchu mt t suy thoi nm 1994 v hy b SSC (my siu va chmsiu dn Superconducting Super Collider) mc d n c xymt na ri. Cc my gia tc ht khc nh l LHC (my va chmhadron ln Large Hadron Collider) ti Geneva ang c xydng. Vi cc my ny cng vi cc quan st khc nh l bc x

phng vi sng, chng ta c th xc nh l chng ta ang sng trnmt ci mng hay khng. Nu ng l chng ta ang sng trn mtmng th c l nguyn l v nhn chn cc m hnh mng t mtvn bch th gm v vn cc v tr c th xy ra trong thuyt-M. Chng ta c th din t cho Miranda trong vThe TempestcaShakespeare:i mt th gii mng miSao c nhiu sinh vt nh th n vy(Nguyn vn:O Brane new world

That has such creatures int.Tc gi nhi li cu ni ca Miranda:i mt th gii mi dng cmSao c nhiu ngi nh th n vyO brave new worldThat has such people int.)

chnh l v tr trong mt v ht.

(Hnh 7.20)S ng ng LEP cho thyh tng ang c v cu trc tng

lai ca My va chm ln Ge-neva, Thy S.

B phn s c xy dngB phn c xy dng



29/29

T H G I I M N GSmith Nguyen Studio.

Documents

Chuong 7 Vu Tru Trong Vo Hat de - Smith.N Studio