ou have shuffled off。 worse； weare still introducing huge amounts of cfcs into the atmosphere every year。 according towayne biddle； 60 million pounds of the stuff； worth 1。5 billion； still finds its way onto themarket every year。 so who is making it？ we are鈥攖hat is to say； many of our largecorporations are still making it at their plants overseas。 it will not be banned in third worldcountries until 2010。
clair patterson died in 1995。 he didn鈥檛 win a nobel prize for his work。 geologists neverdo。 nor； more puzzlingly； did he gain any fame or even much attention from half a century ofconsistent and increasingly selfless achievement。 a good case could be made that he was themost influential geologist of the twentieth century。 yet who has ever heard of clair patterson？
most geology textbooks don鈥檛 mention him。 two recent popular books on the history of thedating of earth actually manage to misspell his name。 in early 2001； a reviewer of one ofthese books in the journal nature made the additional； rather astounding error of thinkingpatterson was a woman。
at all events； thanks to the work of clair patterson by 1953 the earth at last had an ageeveryone could agree on。 the only problem now was it was older than the universe thatcontained it。
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11 MUSTER MARK鈥橲 QUARKS
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in 1911； a british scientist named c。 t。 r。 wilson was studying cloud formations bytramping regularly to the summit of ben nevis； a famously damp scottish mountain； when itoccurred to him that there must be an easier way to study clouds。 back in the cavendish labin cambridge he built an artificial cloud chamber鈥攁 simple device in which he could cooland moisten the air； creating a reasonable model of a cloud in laboratory conditions。
the device worked very well； but had an additional； unexpected benefit。 when heaccelerated an alpha particle through the chamber to seed his make…believe clouds； it left avisible trail鈥攍ike the contrails of a passing airliner。 he had just invented the particle detector。
it provided convincing evidence that subatomic particles did indeed exist。
eventually two other cavendish scientists invented a more powerful proton…beam device；while in california ernest lawrence at berkeley produced his famous and impressivecyclotron； or atom smasher； as such devices were long excitingly known。 all of thesecontraptions worked鈥攁nd indeed still work鈥攐n more or less the same principle； the ideabeing to accelerate a proton or other charged particle to an extremely high speed along a track（sometimes circular； sometimes linear）； then bang it into another particle and see what fliesoff。 that鈥檚 why they were called atom smashers。 it wasn鈥檛 science at its subtlest； but it wasgenerally effective。
as physicists built bigger and more ambitious machines； they began to find or postulateparticles or particle families seemingly without number： muons； pions； hyperons； mesons； k…mesons； higgs bosons； intermediate vector bosons； baryons； tachyons。 even physicists beganto grow a little unfortable。 鈥測oung man；鈥潯nrico fermi replied when a student asked himthe name of a particular particle； 鈥渋f i could remember the names of these particles； i wouldhave been a botanist。鈥�
today accelerators have names that sound like something flash gordon would use inbattle： the super proton synchrotron； the large electron…positron collider； the large hadroncollider； the relativistic heavy ion collider。 using huge amounts of energy （some operateonly at night so that people in neighboring towns don鈥檛 have to witness their lights fadingwhen the apparatus is fired up）； they can whip particles into such a state of liveliness that asingle electron can do forty…seven thousand laps around a four…mile tunnel in a second。 fearshave been raised that in their enthusiasm scientists might inadvertently create a black hole oreven something called 鈥渟trange quarks；鈥潯hich could； theoretically； interact with othersubatomic particles and propagate uncontrollably。 if you are reading this； that hasn鈥檛happened。
finding particles takes a certain amount of concentration。 they are not just tiny and swiftbut also often tantalizingly evanescent。 particles can e into being and be gone again in aslittle as 0。000000000000000000000001 second （10…24）。 even the most sluggish of unstableparticles hang around for no more than 0。0000001 second （10…7）。
some particles are almost ludicrously slippery。 every second the earth is visited by 10；000trillion trillion tiny； all but massless neutrinos （mostly shot out by the nuclear broilings of thesun）； and virtually all of them pass right through the planet and everything that is on it；including you and me； as if it weren鈥檛 there。 to trap just a few of them； scientists need tanksholding up to 12。5 million gallons of heavy water （that is； water with a relative abundance ofdeuterium in it） in underground chambers （old mines usually） where they can鈥檛 be interferedwith by other types of radiation。
very occasionally； a passing neutrino will bang into one of the atomic nuclei in the waterand produce a little puff of energy。 scientists count the puffs and by such means take us veryslightly closer to understanding the fundamental properties of the universe。 in 1998； japaneseobservers reported that neutrinos do have mass； but not a great deal鈥攁bout one ten…millionththat of an electron。
what it really takes to find particles these days is money and lots of it。 there is a curiousinverse relationship in modern physics between the tininess of the thing being sought and thescale of facilities required to do the searching。 cern； the european organization for nuclearresearch； is like a little city。 straddling the border of france and switzerland； it employsthree thousand people and occupies a site that is measured in square miles。 cern boasts astring of magnets that weigh more than the eiffel tower and an underground tunnel oversixteen miles around。
breaking up atoms； as james trefil has noted； is easy； you do it each time you switch on afluorescent light。 breaking up atomic nuclei； however； requires quite a lot of money and agenerous supply of electricity。 getting down to the level of quarks鈥攖he particles that make upparticles鈥攔equires still more： trillions of volts of electricity and the budget of a small centralamerican nation。 cern鈥檚 new large hadron collider； scheduled to begin operations in 2005；will achieve fourteen trillion volts of energy and cost something over 1。5 billion toconstruct。
1but these numbers are as nothing pared with what could have been achieved by； andspent upon； the vast and now unfortunately never…to…be superconducting supercollider； whichbegan being constructed near waxahachie； texas； in the 1980s； before experiencing asupercollision of its own with the united states congress。 the intention of the collider was tolet scientists probe 鈥渢he ultimate nature of matter；鈥潯s it is always put； by re…creating as nearlyas possible the conditions in the universe during its first ten thousand billionths of a second。
the plan was to fling particles through a tunnel fifty…two miles long； achieving a trulystaggering ninety…nine trillion volts of energy。 it was a grand scheme； but would also havecost 8 billion to build （a figure that eventually rose to 10 billion） and hundreds of millionsof dollars a year to run。
in perhaps the finest example in history of pouring money into a hole in the ground；congress spent 2 billion on the project； then canceled it in 1993 after fourteen miles oftunnel had been dug。 so texas now boasts the most expensive hole in the universe。 the siteis； i am told by my friend jeff guinn of the fort worth star…telegram； 鈥渆ssentially a vast；cleared field dotted along the circumference by a series of disappointed small towns。鈥�
1there are practical side effects to all this costly effort。 the world wide web is a cern offshoot。 it wasinvented by a cern scientist； tim berners…lee； in 1989。
since the supercollider debacle particle physicists have set their sights a little lower； buteven paratively modest projects can be quite breathtakingly costly when pared with；well； almost anything。 a proposed neutrino observatory at the old homestake mine in lead；south dakota； would cost 500 million to build鈥攖his in a mine that is already dug鈥攂eforeyou even look at the annual running costs。 there would also be 281 million of 鈥済eneralconversion costs。鈥潯 particle accelerator at fermilab in illinois； meanwhile； cost 260 millionmerely to refit。
particle physics； in short； is a hugely expensive enterprise鈥攂ut it is a productive one。
today the particle count is well over 150； with a further 100 or so suspected； butunfortunately； in the words of richard feynman； 鈥渋t is very difficult to understand therelationships of all these particles； and what nature wants them for； or what the connectionsare from one to another。鈥潯nevitably each time we manage to unlock a box； we find that thereis another locked box inside。 some people think there are particles called tachyons； which cantravel faster than the speed of light。 others long to find gravitons鈥攖he seat of gravity。 atwhat point we reach the irreducible bottom is not easy to say。 carl sagan in cosmos raised thepossibility that if you traveled downward into an electron； you might find that it contained auniverse of its own； recalling all those science fiction stories of the fifties。 鈥渨ithin it；organized into the local equivalent of galaxies and smaller structures； are an immense numberof other； much tinier elementary particles； which are themselves universes at the next leveland so on forever鈥攁n infinite downward regression； universes within universes； endlessly。
and upward as well。鈥�
for most of us it is a world that surpasses understanding。 to read even an elementary guideto particle physics nowadays you must now find your way through lexical thickets such asthis： 鈥渢he charged pion and antipion decay respectively into a muon plus antineutrino and anantimuon plus neutrino with an average lifetime of 2。603 x 10…8seconds； the neutral piondecays into two photons with an average lifetime of about 0。8 x 10…16seconds； and the muonand antimuon deca