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in three minutes； 98 percent of all the matter there is or will ever be has beenproduced。 we have a universe。 it is a place of the most wondrous and gratifying possibility；and beautiful； too。 and it was all done in about the time it takes to make a sandwich。
when this moment happened is a matter of some debate。 cosmologists have long arguedover whether the moment of creation was 10 billion years ago or twice that or something inbetween。 the consensus seems to be heading for a figure of about 13。7 billion years； but thesethings are notoriously difficult to measure； as we shall see further on。 all that can really besaid is that at some indeterminate point in the very distant past； for reasons unknown； therecame the moment known to science as t = 0。 we were on our way。
there is of course a great deal we don鈥檛 know； and much of what we think we know wehaven鈥檛 known； or thought we鈥檝e known； for long。 even the notion of the big bang is quite arecent one。 the idea had been kicking around since the 1920s； when georges lema？tre； abelgian priest…scholar； first tentatively proposed it； but it didn鈥檛 really bee an activenotion in cosmology until the mid…1960s when two young radio astronomers made anextraordinary and inadvertent discovery。
their names were arno penzias and robert wilson。 in 1965； they were trying to make useof a large munications antenna owned by bell laboratories at holmdel； new jersey； butthey were troubled by a persistent background noise鈥攁 steady； steamy hiss that made anyexperimental work impossible。 the noise was unrelenting and unfocused。 it came from everypoint in the sky； day and night； through every season。 for a year the young astronomers dideverything they could think of to track down and eliminate the noise。 they tested everyelectrical system。 they rebuilt instruments； checked circuits； wiggled wires； dusted plugs。
they climbed into the dish and placed duct tape over every seam and rivet。 they climbedback into the dish with brooms and scrubbing brushes and carefully swept it clean of whatthey referred to in a later paper as 鈥渨hite dielectric material；鈥潯r what is known moremonly as bird shit。 nothing they tried worked。
unknown to them； just thirty miles away at princeton university； a team of scientists led byrobert dicke was working on how to find the very thing they were trying so diligently to getrid of。 the princeton researchers were pursuing an idea that had been suggested in the 1940sby the russian…born astrophysicist george gamow that if you looked deep enough into spaceyou should find some cosmic background radiation left over from the big bang。 gamowcalculated that by the time it crossed the vastness of the cosmos； the radiation would reachearth in the form of microwaves。 in a more recent paper he had even suggested an instrumentthat might do the job： the bell antenna at holmdel。 unfortunately； neither penzias andwilson； nor any of the princeton team； had read gamow鈥檚 paper。
the noise that penzias and wilson were hearing was； of course； the noise that gamow hadpostulated。 they had found the edge of the universe； or at least the visible part of it； 90 billiontrillion miles away。 they were 鈥渟eeing鈥潯he first photons鈥攖he most ancient light in theuniverse鈥攖hough time and distance had converted them to microwaves； just as gamow hadpredicted。 in his book the inflationary universe ； alan guth provides an analogy that helps toput this finding in perspective。 if you think of peering into the depths of the universe as likelooking down from the hundredth floor of the empire state building （with the hundredth floorrepresenting now and street level representing the moment of the big bang）； at the time ofwilson and penzias鈥檚 discovery the most distant galaxies anyone had ever detected were onabout the sixtieth floor； and the most distant things鈥攓uasars鈥攚ere on about the twentieth。
penzias and wilson鈥檚 finding pushed our acquaintance with the visible universe to within halfan inch of the sidewalk。
still unaware of what caused the noise； wilson and penzias phoned dicke at princeton anddescribed their problem to him in the hope that he might suggest a solution。 dicke realized at once what the two young men had found。 鈥渨ell； boys； we鈥檝e just been scooped；鈥潯e told hiscolleagues as he hung up the phone。
soon afterward the astrophysical journal published two articles： one by penzias andwilson describing their experience with the hiss； the other by dicke鈥檚 team explaining itsnature。 although penzias and wilson had not been looking for cosmic background radiation；didn鈥檛 know what it was when they had found it； and hadn鈥檛 described or interpreted itscharacter in any paper； they received the 1978 nobel prize in physics。 the princetonresearchers got only sympathy。 according to dennis overbye in lonely hearts of the cosmos； neither penzias nor wilson altogether understood the significance of what they had founduntil they read about it in the new york times 。
incidentally； disturbance from cosmic background radiation is something we have allexperienced。 tune your television to any channel it doesn鈥檛 receive； and about 1 percent of thedancing static you see is accounted for by this ancient remnant of the big bang。 the next timeyou plain that there is nothing on； remember that you can always watch the birth of theuniverse。
although everyone calls it the big bang； many books caution us not to think of it as anexplosion in the conventional sense。 it was； rather； a vast； sudden expansion on a whoppingscale。 so what caused it？
one notion is that perhaps the singularity was the relic of an earlier； collapsed universe鈥攖hat we鈥檙e just one of an eternal cycle of expanding and collapsing universes； like the bladderon an oxygen machine。 others attribute the big bang to what they call 鈥渁 false vacuum鈥潯r 鈥渁scalar field鈥潯r 鈥渧acuum energy鈥濃€攕ome quality or thing； at any rate； that introduced ameasure of instability into the nothingness that was。 it seems impossible that you could getsomething from nothing； but the fact that once there was nothing and now there is a universeis evident proof that you can。 it may be that our universe is merely part of many largeruniverses； some in different dimensions； and that big bangs are going on all the time all overthe place。 or it may be that space and time had some other forms altogether before the bigbang鈥攆orms too alien for us to imagine鈥攁nd that the big bang represents some sort oftransition phase； where the universe went from a form we can鈥檛 understand to one we almostcan。 鈥渢hese are very close to religious questions；鈥潯r。 andrei linde； a cosmologist atstanford； told the new york times in 2001。
the big bang theory isn鈥檛 about the bang itself but about what happened after the bang。
not long after； mind you。 by doing a lot of math and watching carefully what goes on inparticle accelerators； scientists believe they can look back to 10…43seconds after the moment ofcreation； when the universe was still so small that you would have needed a microscope tofind it。 we mustn鈥檛 swoon over every extraordinary number that es before us； but it isperhaps worth latching on to one from time to time just