《万物简史英文版_比尔·布莱森》

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万物简史英文版_比尔·布莱森- 第31部分


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it seemed as if there was no end of strangeness。 for the first time; as james trefil has put it;scientists had encountered 鈥渁n area of the universe that our brains just aren鈥檛 wired tounderstand。鈥潯r as feynman expressed it; 鈥渢hings on a small scale behave nothing like thingson a large scale。鈥潯s physicists delved deeper; they realized they had found a world where notonly could electrons jump from one orbit to another without traveling across any interveningspace; but matter could pop into existence from nothing at all鈥斺減rovided;鈥潯n the words ofalan lightman of mit; 鈥渋t disappears again with sufficient haste。鈥

perhaps the most arresting of quantum improbabilities is the idea; arising from wolfgangpauli鈥檚 exclusion principle of 1925; that the subatomic particles in certain pairs; even whenseparated by the most considerable distances; can each instantly 鈥渒now鈥潯hat the other isdoing。 particles have a quality known as spin and; according to quantum theory; the momentyou determine the spin of one particle; its sister particle; no matter how distant away; willimmediately begin spinning in the opposite direction and at the same rate。

it is as if; in the words of the science writer lawrence joseph; you had two identical poolballs; one in ohio and the other in fiji; and the instant you sent one spinning the other wouldimmediately spin in a contrary direction at precisely the same speed。 remarkably; thephenomenon was proved in 1997 when physicists at the university of geneva sent photonsseven miles in opposite directions and demonstrated that interfering with one provoked aninstantaneous response in the other。

things reached such a pitch that at one conference bohr remarked of a new theory that thequestion was not whether it was crazy; but whether it was crazy enough。 to illustrate thenonintuitive nature of the quantum world; schr?dinger offered a famous thought experimentin which a hypothetical cat was placed in a box with one atom of a radioactive substanceattached to a vial of hydrocyanic acid。 if the particle degraded within an hour; it would triggera mechanism that would break the vial and poison the cat。 if not; the cat would live。 but we could not know which was the case; so there was no choice; scientifically; but to regard 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 鈥減redictfuture events exactly if one cannot even measure the present state of the universe precisely!鈥

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鈥攖he notion at the very heart of thenew physics。 鈥渜uantum theory is very worthy of regard;鈥潯e observed politely; but he reallydidn鈥檛 like it。 鈥済od doesn鈥檛 play dice;鈥潯e said。

4einstein couldn鈥檛 bear the notion that god could create a universe in which some thingswere forever unknowable。 moreover; the idea of action at a distance鈥攖hat one particle couldinstantaneously influence another trillions of miles away鈥攚as 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; 鈥渂y not thinking aboutit。鈥潱゛bove all; there was the problem that quantum physics introduced a level of untidiness thathadn鈥檛 previously existed。 suddenly you needed two sets of laws to explain the behavior ofthe universe鈥攓uantum 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鈥檚 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鈥攙astly so; in fact鈥攂ut 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鈥檚 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鈥檛 hold on to all the protons。

the upshot of all this is that physics ended up with two bodies of laws鈥攐ne for the worldof the very small; one for the universe at large鈥攍eading 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; 鈥渉is colleagues thought; andstill think; that he wasted the second half of his life。鈥

4or at least that is how it is nearly always rendered。 the actual quote was: 鈥渋t seems hard to sneak a look atgod鈥檚 cards。 but that he plays dice and uses 鈥榯elepathic鈥櫋ethods。 。 。 is something that i cannot believe for asingle moment。鈥

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鈥攁s 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。

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10    GETTING THE LEAD OUT

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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鈥攗sually 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鈥檛 bring a little lead into consumers鈥櫋ives。 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; palsies; and convulsions。 in its mostacute form it produces abrupt and terrifying hallucinations; disturbing to victims andonlookers alike; which generally then give way to a and death。 you really don鈥檛 want toget too much lead into your system。

on the other hand; lead was easy to extract and work; and almost embarrassingly profitableto produce industrially鈥攁nd tetraethyl lead did indubitably stop engines from knocking。 so in1923 three of america鈥檚 largest corporations; general motors; du pont; and standard oil ofnew jersey; formed a joint enterprise called the ethyl gasoline corporation (later shortenedto simply ethyl corporation) with a view to making as much tetraethyl lead as the world waswilling to buy; and that proved to be a very great deal。 they called their additive 鈥渆thyl鈥

because it sounded friendlier and less toxic than 鈥渓ead鈥潯nd introduced it for publicconsumption (in more ways than most people realized) on february 1; 1923。

almost at once production workers began to exhibit the staggered gait and confusedfaculties that mark the recently poisoned。 also almost at once; the ethyl corporationembarked on a policy of calm but unyielding denial that would serve it well for decades。 assharon bertsch mcgrayne notes in her absorbing history of industrial chemistry;prometheans in the lab; when employees at one plant developed irreversible delusions; a spokesman blandly informed reporters: 鈥渢hese men probably went insane because theyworked too hard。鈥潯ltogether at least fifteen workers died in the early days of production ofleaded gasoline; and untold numbers of others became ill; often violently so; the exactnumbers are unknown because the pany nearly always managed to hu
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