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tant 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