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ich is to saytypes of vibrations。 vibrations must occur in something； hence the need for； and lastingdevotion to； an ether。 as late as 1909； the great british physicist j。 j。 thomson was insisting：
鈥渢he ether is not a fantastic creation of the speculative philosopher； it is as essential to us asthe air we breathe鈥濃�攖his more than four years after it was pretty incontestably establishedthat it didn鈥檛 exist。 people； in short； were really attached to the ether。
if you needed to illustrate the idea of nineteenth…century america as a land of opportunity；you could hardly improve on the life of albert michelson。 born in 1852 on the german鈥損olish border to a family of poor jewish merchants； he came to the united states with hisfamily as an infant and grew up in a mining camp in california鈥檚 gold rush country； where hisfather ran a dry goods business。 too poor to pay for college； he traveled to washington； d。c。；and took to loitering by the front door of the white house so that he could fall in besidepresident ulysses s。 grant when the president emerged for his daily constitutional。 （it wasclearly a more innocent age。） in the course of these walks； michelson so ingratiated himself tothe president that grant agreed to secure for him a free place at the u。s。 naval academy。 itwas there that michelson learned his physics。
ten years later； by now a professor at the case school in cleveland； michelson becameinterested in trying to measure something called the ether drift鈥攁 kind of head windproduced by moving objects as they plowed through space。 one of the predictions ofnewtonian physics was that the speed of light as it pushed through the ether should vary with2planck was often unlucky in life。 his beloved first wife died early； in 1909； and the younger of his two sonswas killed in the first world war。 he also had twin daughters whom he adored。 one died giving birth。 thesurviving twin went to look after the baby and fell in love with her sisters husband。 they married and two yearslater she died in childbirth。 in 1944； when planck was eighty…five； an allied bomb fell on his house and he losteverything…papers； diaries； a lifetime of accumulations。 the following year his surviving son was caught in aconspiracy to assassinate hitler and executed。
respect to an observer depending on whether the observer was moving toward the source oflight or away from it； but no one had figured out a way to measure this。 it occurred tomichelson that for half the year the earth is traveling toward the sun and for half the year it ismoving away from it； and he reasoned that if you took careful enough measurements atopposite seasons and pared light鈥檚 travel time between the two； you would have youranswer。
michelson talked alexander graham bell； newly enriched inventor of the telephone； intoproviding the funds to build an ingenious and sensitive instrument of michelson鈥檚 owndevising called an interferometer； which could measure the velocity of light with greatprecision。 then； assisted by the genial but shadowy morley； michelson embarked on years offastidious measurements。 the work was delicate and exhausting； and had to be suspended fora time to permit michelson a brief but prehensive nervous breakdown； but by 1887 theyhad their results。 they were not at all what the two scientists had expected to find。
as caltech astrophysicist kip s。 thorne has written： 鈥渢he speed of light turned out to bethe same inall directions and at all seasons。鈥潯t was the first hint in two hundred years鈥攊nexactly two hundred years； in fact鈥攖hat newton鈥檚 laws might not apply all the timeeverywhere。 the michelson…morley oute became； in the words of william h。 cropper；鈥減robably the most famous negative result in the history of physics。鈥潯ichelson was awardeda nobel prize in physics for the work鈥攖he first american so honored鈥攂ut not for twentyyears。 meanwhile； the michelson…morley experiments would hover unpleasantly； like a mustysmell； in the background of scientific thought。
remarkably； and despite his findings； when the twentieth century dawned michelsoncounted himself among those who believed that the work of science was nearly at an end；with 鈥渙nly a few turrets and pinnacles to be added； a few roof bosses to be carved；鈥潯n thewords of a writer in nature。
in fact； of course； the world was about to enter a century of science where many peoplewouldn鈥檛 understand anything and none would understand everything。 scientists would soonfind themselves adrift in a bewildering realm of particles and antiparticles； where things popin and out of existence in spans of time that make nanoseconds look plodding and uneventful；where everything is strange。 science was moving from a world of macrophysics； whereobjects could be seen and held and measured； to one of microphysics； where events transpirewith unimaginable swiftness on scales far below the limits of imagining。 we were about toenter the quantum age； and the first person to push on the door was the so…far unfortunatemax planck。
in 1900； now a theoretical physicist at the university of berlin and at the somewhatadvanced age of forty…two； planck unveiled a new 鈥渜uantum theory；鈥潯hich posited thatenergy is not a continuous thing like flowing water but es in individualized packets；which he called quanta。 this was a novel concept； and a good one。 in the short term it wouldhelp to provide a solution to the puzzle of the michelson…morley experiments in that itdemonstrated that light needn鈥檛 be a wave after all。 in the longer term it would lay thefoundation for the whole of modern physics。 it was； at all events； the first clue that the worldwas about to change。
but the landmark event鈥攖he dawn of a new age鈥攃ame in 1905； when there appeared inthe german physics journal annalen der physik a series of papers by a young swissbureaucrat who had no university affiliation； no access to a laboratory； and the regular use of no library greater than that of the national patent office in bern； where he was employed as atechnical examiner third class。 （an application to be promoted to technical examiner secondclass had recently been rejected。）his name was albert einstein； and in that one eventful year he submitted to annalen derphysik five papers； of which three； according to c。 p。 snow； 鈥渨ere among the greatest in thehistory of physics鈥濃�攐ne examining the photoelectric effect by means of planck鈥檚 newquantum theory； one on the behavior of small particles in suspension （what is known asbrownian motion）； and one outlining a special theory of relativity。
the first won its author a nobel prize and explained the nature of light （and also helped tomake television possible； among other things）。
3the second provided proof that atoms doindeed exist鈥攁 fact that had； surprisingly； been in some dispute。 the third merely changedthe world。
einstein was born in ulm； in southern germany； in 1879； but grew up in munich。 little inhis early life suggested the greatness to e。 famously he didn鈥檛 learn to speak until he wasthree。 in the 1890s； his father鈥檚 electrical business failing； the family moved to milan； butalbert； by now a teenager； went to switzerland to continue his education鈥攖hough he