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and indeed still work—on 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’s why they were called atom smashers。 it wasn’t 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。 “young man；” enrico fermi replied when a student asked himthe name of a particular particle； “if i could remember the names of these particles； i wouldhave been a botanist。”
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’t 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 “strange quarks；” which could； theoretically； interact with othersubatomic particles and propagate uncontrollably。 if you are reading this； that hasn’thappened。
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’t 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’t 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—about 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—the particles that make upparticles—requires still more： trillions of volts of electricity and the budget of a small centralamerican nation。 cern’s 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 “the ultimate nature of matter；” as 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； “essentially a vast；cleared field dotted along the circumference by a series of disappointed small towns。”
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—this in a mine that is already dug—beforeyou even look at the annual running costs。 there would also be 281 million of “generalconversion costs。” a particle accelerator at fermilab in illinois； meanwhile； cost 260 millionmerely to refit。
particle physics； in short； is a hugely expensive enterprise—but it is a