万物简史英文版_比尔·布莱森-第24章

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ons　that　can　never　fail　to　excite　wonder鈥攕ent　the　paper鈥檚　golfing　correspondent；　onehenry　crouch；　to　conduct　the　interview。

crouch　was　hopelessly　out　of　his　depth；　and　got　nearly　everything　wrong。　among　the　morelasting　errors　in　his　report　was　the　assertion　that　einstein　had　found　a　publisher　daring　enoughto　publish　a　book　that　only　twelve　men　鈥渋n　all　the　world　could　prehend。鈥潯�there　was　nosuch　book；　no　such　publisher；　no　such　circle　of　learned　men；　but　the　notion　stuck　anyway。

soon　the　number　of　people　who　could　grasp　relativity　had　been　reduced　even　further　in　thepopular　imagination鈥攁nd　the　scientific　establishment；　it　must　be　said；　did　little　to　disturb　themyth。

when　a　journalist　asked　the　british　astronomer　sir　arthur　eddington　if　it　was　true　that　hewas　one　of　only　three　people　in　the　world　who　could　understand　einstein鈥檚　relativity　theories；eddington　considered　deeply　for　a　moment　and　replied：　鈥渋　am　trying　to　think　who　the　thirdperson　is。鈥潯�in　fact；　the　problem　with　relativity　wasn鈥檛　that　it　involved　a　lot　of　differentialequations；　lorentz　transformations；　and　other　plicated　mathematics　（though　it　did鈥攅veneinstein　needed　help　with　some　of　it）；　but　that　it　was　just　so　thoroughly　nonintuitive。

in　essence　what　relativity　says　is　that　space　and　time　are　not　absolute；　but　relative　to　boththe　observer　and　to　the　thing　being　observed；　and　the　faster　one　moves　the　more　pronouncedthese　effects　bee。　we　can　never　accelerate　ourselves　to　the　speed　of　light；　and　the　harderwe　try　（and　faster　we　go）　the　more　distorted　we　will　bee；　relative　to　an　outside　observer。

almost　at　once　popularizers　of　science　tried　to　e　up　with　ways　to　make　these　conceptsaccessible　to　a　general　audience。　one　of　the　more　successful　attempts鈥攎ercially　atleast鈥攚as　the　abc　of　relativity　by　the　mathematician　and　philosopher　bertrand　russell。　init；　russell　employed　an　image　that　has　been　used　many　times　since。　he　asked　the　reader　toenvision　a　train　one　hundred　yards　long　moving　at　60　percent　of　the　speed　of　light。　tosomeone　standing　on　a　platform　watching　it　pass；　the　train　would　appear　to　be　only　eightyyards　long　and　everything　on　it　would　be　similarly　pressed。　if　we　could　hear　thepassengers　on　the　train　speak；　their　voices　would　sound　slurred　and　sluggish；　like　a　recordplayed　at　too　slow　a　speed；　and　their　movements　would　appear　similarly　ponderous。　even　theclocks　on　the　train　would　seem　to　be　running　at　only　four…fifths　of　their　normal　speed。

however鈥攁nd　here鈥檚　the　thing鈥攑eople　on　the　train　would　have　no　sense　of　thesedistortions。　to　them；　everything　on　the　train　would　seem　quite　normal。　it　would　be　we　on　theplatform　who　looked　weirdly　pressed　and　slowed　down。　it　is　all　to　do；　you　see；　with　yourposition　relative　to　the　moving　object。

this　effect　actually　happens　every　time　you　move。　fly　across　the　united　states；　and　youwill　step　from　the　plane　a　quinzillionth　of　a　second；　or　something；　younger　than　those　you　leftbehind。　even　in　walking　across　the　room　you　will　very　slightly　alter　your　own　experience　oftime　and　space。　it　has　been　calculated　that　a　baseball　thrown　at　a　hundred　miles　an　hour　willpick　up　0。000000000002　grams　of　mass　on　its　way　to　home　plate。　so　the　effects　of　relativityare　real　and　have　been　measured。　the　problem　is　that　such　changes　are　much　too　small　tomake　the　tiniest　detectable　difference　to　us。　but　for　other　things　in　the　universe鈥攍ight；gravity；　the　universe　itself鈥攖hese　are　matters　of　consequence。

so　if　the　ideas　of　relativity　seem　weird；　it　is　only　because　we　don鈥檛　experience　these　sorts　ofinteractions　in　normal　life。　however；　to　turn　to　bodanis　again；　we　all　monly　encounterother　kinds　of　relativity鈥攆or　instance　with　regard　to　sound。　if　you　are　in　a　park　and　someoneis　playing　annoying　music；　you　know　that　if　you　move　to　a　more　distant　spot　the　music　willseem　quieter。　that鈥檚　not　because　the　musicis　quieter；　of　course；　but　simply　that　your　positionrelative　to　it　has　changed。　to　something　too　small　or　sluggish　to　duplicate　this　experience鈥攁snail；　say鈥攖he　idea　that　a　boom　box　could　seem　to　two　observers　to　produce　two　differentvolumes　of　music　simultaneously　might　seem　incredible。

the　most　challenging　and　nonintuitive　of　all　the　concepts　in　the　general　theory　of　relativityis　the　idea　that　time　is　part　of　space。　our　instinct　is　to　regard　time　as　eternal；　absolute；immutable鈥攏othing　can　disturb　its　steady　tick。　in　fact；　according　to　einstein；　time　is　variableand　ever　changing。　it　even　has　shape。　it　is　bound　up鈥斺�渋nextricably　interconnected；鈥潯�instephen　hawking鈥檚　expression鈥攚ith　the　three　dimensions　of　space　in　a　curious　dimensionknown　as　spacetime。

spacetime　is　usually　explained　by　asking　you　to　imagine　something　flat　but　pliant鈥攁mattress；　say；　or　a　sheet　of　stretched　rubber鈥攐n　which　is　resting　a　heavy　round　object；　suchas　an　iron　ball。　the　weight　of　the　iron　ball　causes　the　material　on　which　it　is　sitting　to　stretchand　sag　slightly。　this　is　roughly　analogous　to　the　effect　that　a　massive　object　such　as　the　sun（the　iron　ball）　has　on　spacetime　（the　material）：　it　stretches　and　curves　and　warps　it。　now　ifyou　roll　a　smaller　ball　across　the　sheet；　it　tries　to　go　in　a　straight　line　as　required　by　newton鈥檚laws　of　motion；　but　as　it　nears　the　massive　object　and　the　slope　of　the　sagging　fabric；　it　rollsdownward；　ineluctably　drawn　to　the　more　massive　object。　this　is　gravity鈥攁　product　of　thebending　of　spacetime。

every　object　that　has　mass　creates　a　little　depression　in　the　fabric　of　the　cosmos。　thus　theuniverse；　as　dennis　overbye　has　put　it；　is　鈥渢he　ultimate　sagging　mattress。鈥潯�gravity　on　thisview　is　no　longer　so　much　a　thing　as　an　oute鈥斺�渘ot　a　鈥榝orce鈥櫋�but　a　byproduct　of　thewarping　of　spacetime；鈥潯�in　the　words　of　the　physicist　michio　kaku；　who　goes　on：　鈥渋n　somesense；　gravity　does　not　exist；　what　moves　the　planets　and　stars　is　the　distortion　of　space　andtime。鈥�

of　course　the　sagging　mattress　analogy　can　take　us　only　so　far　because　it　doesn鈥檛incorporate　the　effect　of　time。　but　then　our　brains　can　take　us　only　so　far　because　it　is　sonearly　impossible　to　envision　a　dimension　prising　three　parts　space　to　one　part　time；　allinterwoven　like　the　threads　in　a　plaid　fabric。　at　all　events；　i　think　we　can　agree　that　this　wasan　awfully　big　thought　for　a　young　man　staring　out　the　window　of　a　patent　office　in　thecapital　of　switzerland。

among　much　else；　einstein鈥檚　general　theory　of　relativity　suggested　that　the　universe　mustbe　either　expanding　or　contracting。　but　einstein　was　not　a　cosmologist；　and　he　accepted　theprevailing　wisdom　that　the　universe　was　fixed　and　eternal。　more　or　less　reflexively；　hedropped　into　his　equations　something　called　the　cosmological　constant；　which　arbitrarilycounterbalanced　the　effects　of　gravity；　serving　as　a　kind　of　mathematical　pause　button。　bookson　the　history　of　science　always　forgive　einstein　this　lapse；　but　it　was　actually　a　fairlyappalling　piece　of　science　and　he　knew　it。　he　called　it　鈥渢he　biggest　blunder　of　my　life。鈥�

coincidentally；　at　about　the　time　that　einstein　was　affixing　a　cosmological　constant　to　histheory；　at　the　lowell　observatory　in　arizona；　an　astronomer　with　the　cheerily　intergalacticname　of　vesto　slipher　（who　was　in　fact　from　indiana）　was　taking　spectrographic　readings　ofdistant　stars　and　discovering　that　they　appeared　to　be　moving　away　from　us。　the　universewasn鈥檛　static。　the　stars　slipher　looked　at　showed　unmistakable　signs　of　a　doppler　shift5鈥攖hesame　mechanism　behind　that　distinctive　stretched…out　yee…yummm　sound　cars　make　as　theyflash　past　on　a　racetrack。　the　phenomenon　also　applies　to　light；　and　in　the　case　of　recedinggalaxies　it　is　known　as　a　red　shift　（because　light　moving　away　from　us　shifts　toward　the　redend　of　the　spectrum；　approaching　light　shifts　to　blue）。

slipher　was　the　first　to　notice　this　effect　with　light　and　to　realize　its　potential　importancefor　understanding　the　motions　of　the　cosmos。　unfortunately　no　one　much　noticed　him。　thelowell　observatory；　as　you　will　recall；　was　a　bit　of　an　oddity　thanks　to　percival　lowell鈥檚obsession　with　martian　canals；　which　in　the　1910s　made　it；　in　every　sense；　an　outpost　ofastronomical　endeavor。　slipher　was　unaware　of　einstein鈥檚　theory　of　relativity；　and　the　worldwas　equally　unaware　of　slipher。　so　his　finding　had　no　impact。

glory　instead　would　pass　to　a　large　mass　of　ego　named　edwin　hubble。　hubble　was　born　in1889；　ten　years　after　einstein；　in　a　small　missouri　town　on　the　edge　of　the　ozarks　and　grewup　there　and　in　wheaton；　illinois；　a　suburb　of　chicago。　his　father　was　a　successful　insuranceexecutive；　so　life　was　always　fortable；　and　edwin　enjoyed　a　wealth　of　physicalendowments；　too。　he　was　a　strong　and　gifted　athlete；　charming；　smart；　and　immensely　good…looking鈥斺�渉andsome　almost　to　a　fault；鈥潯�in　the　description　of　william　h。　cropper；　鈥渁n5named　for　johann　christian　doppler；　an　austrian　physicist；　who　first　noticed　the　effect　in　1842。　briefly；　whathappens　is　that　as　a　moving　object　approaches　a　stationary　one　its　sound　waves　bee　bunched　up　as　they　cramup　against　whatever　device　is　receiving　them　（your　ears；　say）；　just　as　you　would　expect　of　anything　that　is　beingpushed　from　behind　toward　an　immobile　object。　this　bunching　is　perceived　by　the　listener　as　a　kind　of　pinchedand　elevated　sound　（the　yee）。　as　the　sound　source　passes；　the　sound　waves　spread　out　and　lengthen；　causing　thepitch　to　drop　abruptly　（the　yummm）。

adonis鈥潯�in　the　words　of　another　admirer。　according　to　his　own　accounts；　he　also　managed　tofit　into　his　life　more　or　less　constant　acts　of　valor鈥攔escuing　drowning　swimmers；　leadingfrightened　men　to　safety　across　the　battlefields　of　france；　embarrassing　world…championboxers　with　knockdown　punches　in　exhibition　bouts。　it　all　seemed　too　good　to　be　true。　it　was。

for　all　his　gifts；　hubble　was　also　an　inveterate　liar。

this　was　more　than　a　little　odd；　for　hubble鈥檚　life　was　filled　from　an　early　age　with　a　levelof　distinction　that　was　at　times　almost　ludicrously　golden。　at　a　single　high　school　track　meetin　1906；　he　won　the　pole　vault；　shot　put；　discus；　hammer　throw；　standing　high　jump；　andrunning　high　jump；　and　was　on　the　winning　mile…relay　team鈥攖hat　is　seven　first　places　in　onemeet鈥攁nd　came　in　third　in　the　broad　jump。　in　the　same　year；　he　set　a　state　record　for　the　highjump　in　illinois。

as　a　scholar　he　was　equally　proficient；　and　had　no　trouble　gaining　admission　to　studyphysics　and　astronomy　at　the　university　of　chicago　（where；　coincidentally；　the　head　of　thedepartment　was　now　albert　michelson）。　there　he　was　selected　to　be　one　of　the　first　rhodesscholars　at　oxford。　three　years　of　english　life　evidently　turned　his　head；　for　he　returned　towheaton　in　1913　wearing　an　inverness　cape；　smoking　a　pipe；　and　talking　with　a　peculiarlyorotund　accent鈥攏ot　quite　british　but　not　quite　not鈥攖hat　would　remain　with　him　for　life。

though　he　later　claimed　to　have　passed　most　of　the　second　decade　of　the　century　practicinglaw　in　kentucky；　in　fact　he　worked　as　a　high　school　teacher　and　basketball　coach　in　newalbany；　indiana；　before　belatedly　attaining　his　doctorate　and　passing　briefly　through　thearmy。　（he　arrived　in　france　one　month　before　the　armistice　and　almost　certainly　never　hearda　shot　fired　in　anger。）in　1919；　now　aged　thirty；　he　moved　to　california　and　took