A Short History of Nearly Everything-第2章

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tion；everything…and　to　do　so　repeatedly。　thats　much　easier　said　than　done；　because　the　process　ofchange　is　random。　to　get　from　〃protoplasmal　primordial　atomic　globule〃　（as　the　gilbert　andsullivan　song　put　it）　to　sentient　upright　modern　human　has　required　you　to　mutate　new　traitsover　and　over　in　a　precisely　timely　manner　for　an　exceedingly　long　while。　so　at　variousperiods　over　the　last　3。8　billion　years　you　have　abhorred　oxygen　and　then　doted　on　it；　grownfins　and　limbs　and　jaunty　sails；　laid　eggs；　flicked　the　air　with　a　forked　tongue；　been　sleek；been　furry；　lived　underground；　lived　in　trees；　been　as　big　as　a　deer　and　as　small　as　a　mouse；and　a　million　things　more。　the　tiniest　deviation　from　any　of　these　evolutionary　shifts；　and　youmight　now　be　licking　algae　from　cave　walls　or　lolling　walrus…like　on　some　stony　shore　ordisgorging　air　through　a　blowhole　in　the　top　of　your　head　before　diving　sixty　feet　for　amouthful　of　delicious　sandworms。

not　only　have　you　been　lucky　enough　to　be　attached　since　time　immemorial　to　a　favoredevolutionary　line；　but　you　have　also　been　extremely…make　that　miraculously…fortunate　in　yourpersonal　ancestry。　consider　the　fact　that　for　3。8　billion　years；　a　period　of　time　older　than　theearths　mountains　and　rivers　and　oceans；　every　one　of　your　forebears　on　both　sides　has　beenattractive　enough　to　find　a　mate；　healthy　enough　to　reproduce；　and　sufficiently　blessed　by　fateand　circumstances　to　live　long　enough　to　do　so。　not　one　of　your　pertinent　ancestors　wassquashed；　devoured；　drowned；　starved；　stranded；　stuck　fast；　untimely　wounded；　or　otherwisedeflected　from　its　lifes　quest　of　delivering　a　tiny　charge　of　genetic　material　to　the　rightpartner　at　the　right　moment　in　order　to　perpetuate　the　only　possible　sequence　of　hereditarybinations　that　could　result…eventually；　astoundingly；　and　all　too　briefly…in　you。

this　is　a　book　about　how　it　happened…in　particular　how　we　went　from　there　being　nothing　atall　to　there　being　something；　and　then　how　a　little　of　that　something　turned　into　us；　and　alsosome　of　what　happened　in　between　and　since。　thats　a　great　deal　to　cover；　of　course；　which　iswhy　the　book　is　called　a　short　history　of　nearly　everything；　even　though　it　isnt　really。　itcouldnt　be。　but　with　luck　by　the　time　we　finish　it　will　feel　as　if　it　is。

my　own　starting　point；　for　what　its　worth；　was　an　illustrated　science　book　that　i　had　as　aclassroom　text　when　i　was　in　fourth　or　fifth　grade。　the　book　was　a　standard…issue　1950sschoolbookbattered；　unloved；　grimly　hefty…but　near　the　front　it　had　an　illustration　that　justcaptivated　me：　a　cutaway　diagram　showing　the　earths　interior　as　it　would　look　if　you　cut　intothe　planet　with　a　large　knife　and　carefully　withdrew　a　wedge　representing　about　a　quarter　ofits　bulk。

its　hard　to　believe　that　there　was　ever　a　time　when　i　had　not　seen　such　an　illustrationbefore；　but　evidently　i　had　not　for　i　clearly　remember　being　transfixed。　i　suspect；　in　honesty；my　initial　interest　was　based　on　a　private　image　of　streams　of　unsuspecting　eastboundmotorists　in　the　american　plains　states　plunging　over　the　edge　of　a　sudden　4；000…mile…highcliff　running　between　central　america　and　the　north　pole；　but　gradually　my　attention　did　turnin　a　more　scholarly　manner　to　the　scientific　import　of　the　drawing　and　the　realization　that　theearth　consisted　of　discrete　layers；　ending　in　the　center　with　a　glowing　sphere　of　iron　andnickel；　which　was　as　hot　as　the　surface　of　the　sun；　according　to　the　caption；　and　i　rememberthinking　with　real　wonder：　〃how　do　they　know　that？〃i　didnt　doubt　the　correctness　of　the　information　for　an　instant…i　still　tend　to　trust　thepronouncements　of　scientists　in　the　way　i　trust　those　of　surgeons；　plumbers；　and　otherpossessors　of　arcane　and　privileged　information…but　i　couldnt　for　the　life　of　me　conceive　howany　human　mind　could　work　out　what　spaces　thousands　of　miles　below　us；　that　no　eye　hadever　seen　and　no　x　ray　could　penetrate；　could　look　like　and　be　made　of。　to　me　that　was　just　amiracle。　that　has　been　my　position　with　science　ever　since。

excited；　i　took　the　book　home　that　night　and　opened　it　before　dinner…an　action　that　i　expectprompted　my　mother　to　feel　my　forehead　and　ask　if　i　was　all　right…and；　starting　with　the　firstpage；　i　read。

and　heres　the　thing。　it　wasnt　exciting　at　all。　it　wasnt　actually　altogether　prehensible。

above　all；　it　didnt　answer　any　of　the　questions　that　the　illustration　stirred　up　in　a　normalinquiring　mind：　how　did　we　end　up　with　a　sun　in　the　middle　of　our　planet？　and　if　it　isburning　away　down　there；　why　isnt　the　ground　under　our　feet　hot　to　the　touch？　and　why　isntthe　rest　of　the　interior　melting…or　is　it？　and　when　the　core　at　last　burns　itself　out；　will　some　ofthe　earth　slump　into　the　void；　leaving　a　giant　sinkhole　on　the　surface？　and　how　do　you　knowthis？　how　did　you　figure　it　out？

but　the　author　was　strangely　silent　on　such　details…indeed；　silent　on　everything　butanticlines；　synclines；　axial　faults；　and　the　like。　it　was　as　if　he　wanted　to　keep　the　good　stuffsecret　by　making　all　of　it　soberly　unfathomable。　as　the　years　passed；　i　began　to　suspect　thatthis　was　not　altogether　a　private　impulse。　there　seemed　to　be　a　mystifying　universalconspiracy　among　textbook　authors　to　make　certain　the　material　they　dealt　with　never　strayedtoo　near　the　realm　of　the　mildly　interesting　and　was　always　at　least　a　longdistance　phone　callfrom　the　frankly　interesting。

i　now　know　that　there　is　a　happy　abundance　of　science　writers　who　pen　the　most　lucid　andthrilling　prose…timothy　ferris；　richard　fortey；　and　tim　flannery　are　three　that　jump　out　froma　single　station　of　the　alphabet　（and　thats　not　even　to　mention　the　late　but　godlike　richardfeynman）…but　sadly　none　of　them　wrote　any　textbook　i　ever　used。　all　mine　were　written　bymen　（it　was　always　men）　who　held　the　interesting　notion　that　everything　became　clear　whenexpressed　as　a　formula　and　the　amusingly　deluded　belief　that　the　children　of　america　wouldappreciate　having　chapters　end　with　a　section　of　questions　they　could　mull　over　in　their　owntime。　so　i　grew　up　convinced　that　science　was　supremely　dull；　but　suspecting　that　it　needntbe；　and　not　really　thinking　about　it　at　all　if　i　could　help　it。　this；　too；　became　my　position　for　along　time。

then　much　later…about　four　or　five　years　ago…i　was　on　a　long　flight　across　the　pacific；staring　idly　out　the　window　at　moonlit　ocean；　when　it　occurred　to　me　with　a　certainunfortable　forcefulness　that　i　didnt　know　the　first　thing　about　the　only　planet　i　was　evergoing　to　live　on。　i　had　no　idea；　for　example；　why　the　oceans　were　salty　but　the　great　lakeswerent。　didnt　have　the　faintest　idea。　i　didnt　know　if　the　oceans　were　growing　more　saltywith　time　or　less；　and　whether　ocean　salinity　levels　was　something　i　should　be　concernedabout　or　not。　（i　am　very　pleased　to　tell　you　that　until　the　late　1970s　scientists　didnt　know　theanswers　to　these　questions　either。　they　just　didnt　talk　about　it　very　audibly。）and　ocean　salinity　of　course　represented　only　the　merest　sliver　of　my　ignorance。　i　didntknow　what　a　proton　was；　or　a　protein；　didnt　know　a　quark　from　a　quasar；　didnt　understandhow　geologists　could　look　at　a　layer　of　rock　on　a　canyon　wall　and　tell　you　how　old　it　was；didnt　know　anything　really。　i　became　gripped　by　a　quiet；　unwonted　urge　to　know　a　littleabout　these　matters　and　to　understand　how　people　figured　them　out。　that　to　me　remained　thegreatest　of　all　amazements…how　scientists　work　things　out。　how　does　anybody　know　howmuch　the　earth　weighs　or　how　old　its　rocks　are　or　what　really　is　way　down　there　in　thecenter？　how　can　they　know　how　and　when　the　universe　started　and　what　it　was　like　when　itdid？　how　do　they　know　what　goes　on　inside　an　atom？　and　how；　e　to　that…or　perhapsabove　all…can　scientists　so　often　seem　to　know　nearly　everything　but　then　still　cant　predict　anearthquake　or　even　tell　us　whether　we　should　take　an　umbrella　with　us　to　the　races　nextwednesday？

so　i　decided　that　i　would　devote　a　portion　of　my　life…three　years；　as　it　now　turns　out…toreading　books　and　journals　and　finding　saintly；　patient　experts　prepared　to　answer　a　lot　ofoutstandingly　dumb　questions。　the　idea　was　to　see　if　it　isnt　possible　to　understand　andappreciate…marvel　at；　enjoy　even…the　wonder　and　acplishments　of　science　at　a　level　thatisnt　too　technical　or　demanding；　but　isnt　entirely　superficial　either。

that　was　my　idea　and　my　hope；　and　that　is　what　the　book　that　follows　is　intended　to　be。

anyway；　we　have　a　great　deal　of　ground　to　cover　and　much　less　than　650；000　hours　in　whichto　do　it；　so　lets　begin。

。。



PART　　I　　　LOST　IN　THE　COSMOS

小？说网
they’re　all　in　the　same　plane。

they’re　all　going　around　in　the　same　direction。　。　。　。　

it’s　perfect；　you　know。　　

it’s　gorgeous。　

it’s　almost　uncanny。　　

…astronomer　geoffrey　marcy　

describing　the　solar　system

。d　　。



1　　　HOW　TO　BUILD　A　UNIVERSENO　MATTER

…小……说。网
how　hard　you　try　you　will　never　be　able　to　grasp　just　how　tiny；　how　spatiallyunassuming；　is　a　proton。　it　is　just　way　too　small。

a　proton　is　an　infinitesimal　part　of　an　atom；　which　is　itself　of　course　an　insubstantial　thing。

protons　are　so　small　that　a　little　dib　of　ink　like　the　dot　on　this　i　can　hold　something　in　theregion　of　500；000；000；000　of　them；　rather　more　than　the　number　of　seco