按键盘上方向键 ← 或 → 可快速上下翻页，按键盘上的 Enter 键可回到本书目录页，按键盘上方向键 ↑ 可回到本页顶部！
————未阅读完？加入书签已便下次继续阅读！
gard thecat as 100 percent alive and 100 percent dead at the same time。 this means； as stephenhawking has observed with a touch of understandable excitement； that one cannot “predictfuture events exactly if one cannot even measure the present state of the universe precisely！”
because of its oddities； many physicists disliked quantum theory； or at least certain aspectsof it； and none more so than einstein。 this was more than a little ironic since it was he； in hisannus mirabilis of 1905； who had so persuasively explained how photons of light couldsometimes behave like particles and sometimes like waves—the notion at the very heart of thenew physics。 “quantum theory is very worthy of regard；” he observed politely； but he reallydidn’t like it。 “god doesn’t play dice；” he said。
4einstein couldn’t bear the notion that god could create a universe in which some thingswere forever unknowable。 moreover； the idea of action at a distance—that one particle couldinstantaneously influence another trillions of miles away—was a stark violation of the specialtheory of relativity。 this expressly decreed that nothing could outrace the speed of light andyet here were physicists insisting that； somehow； at the subatomic level； information could。
（no one； incidentally； has ever explained how the particles achieve this feat。 scientists havedealt with this problem； according to the physicist yakir aharanov； “by not thinking aboutit。”）above all； there was the problem that quantum physics introduced a level of untidiness thathadn’t previously existed。 suddenly you needed two sets of laws to explain the behavior ofthe universe—quantum theory for the world of the very small and relativity for the largeruniverse beyond。 the gravity of relativity theory was brilliant at explaining why planetsorbited suns or why galaxies tended to cluster； but turned out to have no influence at all at theparticle level。 to explain what kept atoms together； other forces were needed； and in the1930s two were discovered： the strong nuclear force and weak nuclear force。 the strong forcebinds atoms together； it’s what allows protons to bed down together in the nucleus。 the weakforce engages in more miscellaneous tasks； mostly to do with controlling the rates of certainsorts of radioactive decay。
the weak nuclear force； despite its name； is ten billion billion billion times stronger thangravity； and the strong nuclear force is more powerful still—vastly so； in fact—but theirinfluence extends to only the tiniest distances。 the grip of the strong force reaches out only toabout 1/100；000 of the diameter of an atom。 that’s why the nuclei of atoms are so pactedand dense and why elements with big； crowded nuclei tend to be so unstable： the strong forcejust can’t hold on to all the protons。
the upshot of all this is that physics ended up with two bodies of laws—one for the worldof the very small； one for the universe at large—leading quite separate lives。 einstein dislikedthat； too。 he devoted the rest of his life to searching for a way to tie up these loose ends byfinding a grand unified theory； and always failed。 from time to time he thought he had it； butit always unraveled on him in the end。 as time passed he became increasingly marginalizedand even a little pitied。 almost without exception； wrote snow； “his colleagues thought； andstill think； that he wasted the second half of his life。”
4or at least that is how it is nearly always rendered。 the actual quote was： “it seems hard to sneak a look atgod’s cards。 but that he plays dice and uses ‘telepathic’ methods。 。 。 is something that i cannot believe for asingle moment。”
elsewhere； however； real progress was being made。 by the mid…1940s scientists hadreached a point where they understood the atom at an extremely profound level—as they alltoo effectively demonstrated in august 1945 by exploding a pair of atomic bombs over japan。
by this point physicists could be excused for thinking that they had just about conqueredthe atom。 in fact； everything in particle physics was about to get a whole lot moreplicated。 but before we take up that slightly exhausting story； we must bring anotherstraw of our history up to date by considering an important and salutary tale of avarice； deceit；bad science； several needless deaths； and the final determination of the age of the earth。
．．
10GETTING THE LEAD OUT
gxiaoshuowang
in the late 1940s； a graduate student at the university of chicago named clair patterson（who was； first name notwithstanding； an iowa farm boy by origin） was using a new methodof lead isotope measurement to try to get a definitive age for the earth at last。 unfortunatelyall his samples came up contaminated—usually wildly so。 most contained something like twohundred times the levels of lead that would normally be expected to occur。 many years wouldpass before patterson realized that the reason for this lay with a regrettable ohio inventornamed thomas midgley； jr。
midgley was an engineer by training； and the world would no doubt have been a safer placeif he had stayed so。 instead； he developed an interest in the industrial applications ofchemistry。 in 1921； while working for the general motors research corporation in dayton；ohio； he investigated a pound called tetraethyl lead （also known； confusingly； as leadtetraethyl）； and discovered that it significantly reduced the juddering condition known asengine knock。
even though lead was widely known to be dangerous； by the early years of the twentiethcentury it could be found in all manner of consumer products。 food came in cans sealed withlead solder。 water was often stored in lead…lined tanks。 it was sprayed onto fruit as a pesticidein the form of lead arsenate。 it even came as part of the packaging of toothpaste tubes。 hardlya product existed that didn’t bring a little lead into consumers’ lives。 however； nothing gave ita greater and more lasting intimacy than its addition to gasoline。
lead is a neurotoxin。 get too much of it and you can irreparably damage the brain andcentral nervous system。 among the many symptoms associated with overexposure areblindness； insomnia； kidney failure； hearing loss； cancer； p