万物简史英文版_比尔·布莱森-第3章

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　when　georges　lema？tre；　abelgian　priest…scholar；　first　tentatively　proposed　it；　but　it　didn鈥檛　really　bee　an　activenotion　in　cosmology　until　the　mid…1960s　when　two　young　radio　astronomers　made　anextraordinary　and　inadvertent　discovery。

their　names　were　arno　penzias　and　robert　wilson。　in　1965；　they　were　trying　to　make　useof　a　large　munications　antenna　owned　by　bell　laboratories　at　holmdel；　new　jersey；　butthey　were　troubled　by　a　persistent　background　noise鈥攁　steady；　steamy　hiss　that　made　anyexperimental　work　impossible。　the　noise　was　unrelenting　and　unfocused。　it　came　from　everypoint　in　the　sky；　day　and　night；　through　every　season。　for　a　year　the　young　astronomers　dideverything　they　could　think　of　to　track　down　and　eliminate　the　noise。　they　tested　everyelectrical　system。　they　rebuilt　instruments；　checked　circuits；　wiggled　wires；　dusted　plugs。

they　climbed　into　the　dish　and　placed　duct　tape　over　every　seam　and　rivet。　they　climbedback　into　the　dish　with　brooms　and　scrubbing　brushes　and　carefully　swept　it　clean　of　whatthey　referred　to　in　a　later　paper　as　鈥渨hite　dielectric　material；鈥潯�or　what　is　known　moremonly　as　bird　shit。　nothing　they　tried　worked。

unknown　to　them；　just　thirty　miles　away　at　princeton　university；　a　team　of　scientists　led　byrobert　dicke　was　working　on　how　to　find　the　very　thing　they　were　trying　so　diligently　to　getrid　of。　the　princeton　researchers　were　pursuing　an　idea　that　had　been　suggested　in　the　1940sby　the　russian…born　astrophysicist　george　gamow　that　if　you　looked　deep　enough　into　spaceyou　should　find　some　cosmic　background　radiation　left　over　from　the　big　bang。　gamowcalculated　that　by　the　time　it　crossed　the　vastness　of　the　cosmos；　the　radiation　would　reachearth　in　the　form　of　microwaves。　in　a　more　recent　paper　he　had　even　suggested　an　instrumentthat　might　do　the　job：　the　bell　antenna　at　holmdel。　unfortunately；　neither　penzias　andwilson；　nor　any　of　the　princeton　team；　had　read　gamow鈥檚　paper。

the　noise　that　penzias　and　wilson　were　hearing　was；　of　course；　the　noise　that　gamow　hadpostulated。　they　had　found　the　edge　of　the　universe；　or　at　least　the　visible　part　of　it；　90　billiontrillion　miles　away。　they　were　鈥渟eeing鈥潯�the　first　photons鈥攖he　most　ancient　light　in　theuniverse鈥攖hough　time　and　distance　had　converted　them　to　microwaves；　just　as　gamow　hadpredicted。　in　his　book　the　inflationary　universe　；　alan　guth　provides　an　analogy　that　helps　toput　this　finding　in　perspective。　if　you　think　of　peering　into　the　depths　of　the　universe　as　likelooking　down　from　the　hundredth　floor　of　the　empire　state　building　（with　the　hundredth　floorrepresenting　now　and　street　level　representing　the　moment　of　the　big　bang）；　at　the　time　ofwilson　and　penzias鈥檚　discovery　the　most　distant　galaxies　anyone　had　ever　detected　were　onabout　the　sixtieth　floor；　and　the　most　distant　things鈥攓uasars鈥攚ere　on　about　the　twentieth。

penzias　and　wilson鈥檚　finding　pushed　our　acquaintance　with　the　visible　universe　to　within　halfan　inch　of　the　sidewalk。

still　unaware　of　what　caused　the　noise；　wilson　and　penzias　phoned　dicke　at　princeton　anddescribed　their　problem　to　him　in　the　hope　that　he　might　suggest　a　solution。　dicke　realized　atonce　what　the　two　young　men　had　found。　鈥渨ell；　boys；　we鈥檝e　just　been　scooped；鈥潯�he　told　hiscolleagues　as　he　hung　up　the　phone。

soon　afterward　the　astrophysical　journal　published　two　articles：　one　by　penzias　andwilson　describing　their　experience　with　the　hiss；　the　other　by　dicke鈥檚　team　explaining　itsnature。　although　penzias　and　wilson　had　not　been　looking　for　cosmic　background　radiation；didn鈥檛　know　what　it　was　when　they　had　found　it；　and　hadn鈥檛　described　or　interpreted　itscharacter　in　any　paper；　they　received　the　1978　nobel　prize　in　physics。　the　princetonresearchers　got　only　sympathy。　according　to　dennis　overbye　in　lonely　hearts　of　the　cosmos；　neither　penzias　nor　wilson　altogether　understood　the　significance　of　what　they　had　founduntil　they　read　about　it　in　the　new　york　times　。

incidentally；　disturbance　from　cosmic　background　radiation　is　something　we　have　allexperienced。　tune　your　television　to　any　channel　it　doesn鈥檛　receive；　and　about　1　percent　of　thedancing　static　you　see　is　accounted　for　by　this　ancient　remnant　of　the　big　bang。　the　next　timeyou　plain　that　there　is　nothing　on；　remember　that　you　can　always　watch　the　birth　of　theuniverse。

although　everyone　calls　it　the　big　bang；　many　books　caution　us　not　to　think　of　it　as　anexplosion　in　the　conventional　sense。　it　was；　rather；　a　vast；　sudden　expansion　on　a　whoppingscale。　so　what　caused　it？

one　notion　is　that　perhaps　the　singularity　was　the　relic　of　an　earlier；　collapsed　universe鈥攖hat　we鈥檙e　just　one　of　an　eternal　cycle　of　expanding　and　collapsing　universes；　like　the　bladderon　an　oxygen　machine。　others　attribute　the　big　bang　to　what　they　call　鈥渁　false　vacuum鈥潯�or　鈥渁scalar　field鈥潯�or　鈥渧acuum　energy鈥濃�攕ome　quality　or　thing；　at　any　rate；　that　introduced　ameasure　of　instability　into　the　nothingness　that　was。　it　seems　impossible　that　you　could　getsomething　from　nothing；　but　the　fact　that　once　there　was　nothing　and　now　there　is　a　universeis　evident　proof　that　you　can。　it　may　be　that　our　universe　is　merely　part　of　many　largeruniverses；　some　in　different　dimensions；　and　that　big　bangs　are　going　on　all　the　time　all　overthe　place。　or　it　may　be　that　space　and　time　had　some　other　forms　altogether　before　the　bigbang鈥攆orms　too　alien　for　us　to　imagine鈥攁nd　that　the　big　bang　represents　some　sort　oftransition　phase；　where　the　universe　went　from　a　form　we　can鈥檛　understand　to　one　we　almostcan。　鈥渢hese　are　very　close　to　religious　questions；鈥潯�dr。　andrei　linde；　a　cosmologist　atstanford；　told　the　new　york　times　in　2001。

the　big　bang　theory　isn鈥檛　about　the　bang　itself　but　about　what　happened　after　the　bang。

not　long　after；　mind　you。　by　doing　a　lot　of　math　and　watching　carefully　what　goes　on　inparticle　accelerators；　scientists　believe　they　can　look　back　to　10…43seconds　after　the　moment　ofcreation；　when　the　universe　was　still　so　small　that　you　would　have　needed　a　microscope　tofind　it。　we　mustn鈥檛　swoon　over　every　extraordinary　number　that　es　before　us；　but　it　isperhaps　worth　latching　on　to　one　from　time　to　time　just　to　be　reminded　of　their　ungraspableand　amazing　breadth。　thus　10…43is　0。0000000000000000000000000000000000000000001；　orone　10　million　trillion　trillion　trillionths　of　a　second。

**a　word　on　scientific　notation：　since　very　large　numbers　are　cumbersome　to　write　and　nearly　impossible　to　read；　scientistsuse　a　shorthand　involving　powers　（or　multiples）　of　ten　in　which；　for　instance；　10；000；000；000　is　written　1010　and　6；500；000bees　6。5　x　106。　the　principle　is　based　very　simply　on　multiples　of　ten：　10　x　10　（or　100）　bees　102；　10　x　10　x　10　（or1；000）　is　103；　and　so　on；　obviously　and　indefinitely。　the　little　superscript　number　signifies　the　number　of　zeroes　followingthe　larger　principal　number。　negative　notations　provide　latter　in　print　（especially　essentially　a　mirror　image；　with　thesuperscript　number　indicating　the　number　of　spaces　to　the　right　of　the　decimal　point　（so　10…4　means　0。0001）。　though　i　salutethe　principle；　it　remains　an　amazement　to　me　that　anyone　seeing　〃1。4　x　109　km3鈥櫋�would　see　at　once　that　that　signifies　1。4most　of　what　we　know；　or　believe　we　know；　about　the　early　moments　of　the　universe　isthanks　to　an　idea　called　inflation　theory　first　propounded　in　1979　by　a　junior　particlephysicist；　then　at　stanford；　now　at　mit；　named　alan　guth。　he　was　thirty…two　years　old　and；by　his　own　admission；　had　never　done　anything　much　before。　he　would　probably　never　havehad　his　great　theory　except　that　he　happened　to　attend　a　lecture　on　the　big　bang　given　bynone　other　than　robert　dicke。　the　lecture　inspired　guth　to　take　an　interest　in　cosmology；　andin　particular　in　the　birth　of　the　universe。

the　eventual　result　was　the　inflation　theory；　which　holds　that　a　fraction　of　a　moment　afterthe　dawn　of　creation；　the　universe　underwent　a　sudden　dramatic　expansion。　it　inflated鈥攊neffect　ran　away　with　itself；　doubling　in　size　every　10…34seconds。　the　whole　episode　may　havelasted　no　more　than　10…30seconds鈥攖hat鈥檚　one　million　million　million　million　millionths　of　asecond鈥攂ut　it　changed　the　universe　from　something　you　could　hold　in　your　hand　tosomething　at　least　10；000；000；000；000；000；000；000；000　times　bigger。　inflation　theoryexplains　the　ripples　and　eddies　that　make　our　universe　possible。　without　it；　there　would　be　noclumps　of　matter　and　thus　no　stars；　just　drifting　gas　and　everlasting　darkness。

according　to　guth鈥檚　theory；　at　one　ten…millionth　of　a　trillionth　of　a　trillionth　of　a　trillionthof　a　second；　gravity　emerged。　after　another　ludicrously　brief　interval　it　was　joined　byelectromagnetism　and　the　strong　and　weak　nuclear　forces鈥攖he　stuff　of　physics。　these　werejoined　an　instant　later　by　swarms　of　elementary　particles鈥攖he　stuff　of　stuff。　from　nothing　atall；　suddenly　there　were　swarms　of　photons；　protons；　electrons；　neutrons；　and　much　else鈥攂etween　1079and　1089of　each；　according　to　the　standard　big　bang　theory。

such　quantities　are　of　course　ungraspable。　it　is　enough　to　know　that　in　a　single　crackinginstant　we　were　endowed　with　a　universe　that　was　vast鈥攁t　least　a　hundred　billion　light…yearsacross；　according　to　the　theory；　but　possibly　any　size　up　to　infinite鈥攁nd　perfectly　arrayed　forthe　creation　of　stars；　galaxies；　and　other　plex　systems。

what　is　extraordinary　from　our　point　of　view　is　how　well　it　turned　out　for　us。　if　theuniverse　had　formed　just　a　tiny　bit　differently鈥攊f　gravity　were　fractionally　stronger　orweaker；　if　the　expansion　had　proceeded　just　a　little　more　slowly　or　swiftly鈥攖hen　there　mightnever　have　been　stable　elements　to　make　you　and　me　and　the　ground　we　stand　on。　had　gravitybeen　a　trifle　stronger；　the　universe　itself　might　have　collapsed　like　a　badly　erected　tent；without　precisely　the　right　values　to　give　it　the　right　dimensions　and　density　and　ponentparts。　had　it　been　weaker；　however；　nothing　would　have　coalesced。　the　universe　would　haveremained　forever　a　dull；　scattered　void。

this　is　one　reason　that　some　experts　believe　there　may　have　been　many　other　big　bangs；perhaps　trillions　and　trillions　of　them；　spread　through　the　mighty　span　of　eternity；　and　that　thereason　we　exist　in　this　particular　one　is　that　this　is　one　we　could　exist　in。　as　edward　p。　tryonof　columbia　university　once　put　it：　鈥渋n　answer　to　the　question　of　why　it　happened；　i　offer　themodest　proposal　that　our　universe　is　simply　one　of　those　things　which　happen　from　time　tobillion　cubic　kilometers；　and　no　less　a　wonder　that　they　would　choose　the　former　over　the　in　a　book　designed　for　the　generalreader；　where　the　example　was　found）。　on　the　assumption　that　many　general　readers　are　as　unmathematical　as　i　am；　i　will　usethem　sparingly；　though　they　are　occasionally　unavoidable；　not　least　in　a　chapter　dealing　with　things　on　a　cosmic　scale。

time。鈥潯�to　which　adds　guth：　鈥渁lthough　the　creation　of　a　universe　might　be　very　unlikely；tryon　emphasized　that　no　one　had　counted　the　failed　attempts。鈥�

martin　rees；　britain鈥檚　astronomer　royal；　believes　that　there　are　many　universes；　possibly　aninfinite　number；　each　with　different　attributes；　in　different　binations；　and　that　we　simplylive　in　one　that　bines　things　in　the　way　that　allows　us　to　exist。　he　makes