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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 decay respectively into 。 。 。鈥潯nd so it runs on鈥攁nd this from a book for thegeneral reader by one of the （normally） most lucid of interpreters； steven weinberg。
in the 1960s； in an attempt to bring just a little simplicity to matters； the caltech physicistmurray gell…mann invented a new class of particles； essentially； in the words of stevenweinberg； 鈥渢o restore some economy to the multitude of hadrons鈥濃�攁 collective term used byphysicists for protons； neutrons； and other particles governed by the strong nuclear force。
gell…mann鈥檚 theory was that all hadrons were made up of still smaller； even morefundamental particles。 his colleague richard feynman wanted to call these new basicparticles partons； as in dolly； but was overruled。 instead they became known as quarks。
gell…mann took the name from a line in finnegans wake： 鈥渢hree quarks for mustermark！鈥潯。╠iscriminating physicists rhyme the word with storks； not larks； even though thelatter is almost certainly the pronunciation joyce had in mind。） the fundamental simplicity ofquarks was not long lived。 as they became better understood it was necessary to introducesubdivisions。 although quarks are much too small to have color or taste or any other physicalcharacteristics we would recognize； they became clumped into six categories鈥攗p； down；strange； charm； top； and bottom鈥攚hich physicists oddly refer to as their 鈥渇lavors；鈥潯nd theseare further divided into the colors red； green； and blue。 （one suspects that it was not altogethercoincidental that these terms were first applied in california during the age of psychedelia。） eventually out of all this emerged what is called the standard model； which is essentially asort of parts kit for the subatomic world。 the standard model consists of six quarks； sixleptons； five known bosons and a postulated sixth； the higgs boson （named for a scottishscientist； peter higgs）； plus three of the four physical forces： the strong and weak nuclearforces and electromagnetism。
the arrangement essentially is that