"Annenberg Media" "¶" "C" "TODAY, I'LL TALK ABOUT PERHAPS" "THE MOST FAMOUS EXPERIMENT" "IN THE HISTORY OF PHYSICS." "IT'S CALLED THE MICHELSON-MORLEY EXPERIMENT." "IT WAS DESIGNED TO DETECT THE MOTION OF THE EARTH" "THROUGH THE LUMINIFEROUS ETHER." "THE ETHER WAS AN INVENTION OF 19th-CENTURY PHYSICISTS" "TO EXPLAIN HOW LIGHT COULD BE TRANSMITTED" "THROUGH EMPTY SPACE BETWEEN THE SUN AND THE EARTH." "PHYSICS HAS ITS FOLKLORE AND ITS LEGENDS," "JUST LIKE ANY OTHER CULTURE." "FOR EXAMPLE, THE STORY OF ISAAC NEWTON AND THE APPLE." "WELL, THERE'S A LEGEND" "ABOUT THE MICHELSON-MORLEY EXPERIMENT" "THAT'S JUST AS DEEPLY ROOTED" "AS THE STORY ABOUT ISAAC AND THE APPLE." "IT GOES LIKE THIS" "MICHELSON AND MORLEY DID THEIR EXPERIMENT" "AND PROVED THERE WAS NO ETHER." "SO ALBERT EINSTEIN WAS FORCED TO INVENT" "THE THEORY OF RELATIVITY" "IN ORDER TO EXPLAIN THAT RESULT." "THE EXPERIMENT WAS DONE AT WHAT WAS THEN CALLED" "THE CASE INSTITUTE OF TECHNOLOGY" "IN CLEVELAND, OHIO, IN 1887." "FOR THAT EXPERIMENT TO HAVE BEEN DONE IN CLEVELAND IN 1887" "WAS SOMETHING LIKE THE FIRST REAL THEORY OF ELECTRICITY" "COMING OUT OF PHILADELPHIA MORE THAN A CENTURY BEFORE." "IN THE 1880s, THE UNITED STATES" "WAS STILL THE SCIENTIFIC WILDERNESS" "AND ESPECIALLY CLEVELAND, OHIO." "IT'S JUST POSSIBLE THAT THE MICHELSON-MORLEY EXPERIMENT" "WAS THE MOST IMPORTANT THING" "TO HAPPEN IN CLEVELAND" "UNTIL SATCHEL PAIGE PITCHED FOR THE INDIANS." "THE MOST REMARKABLE THING ABOUT THIS WHOLE TALE" "MAY BE THE FACT THAT ALBERT MICHELSON," "FOR THE REMAINING 50 YEARS OF HIS LIFE," "CONSIDERED HIS GREAT EXPERIMENT TO HAVE BEEN A FAILURE." "TODAY, WE'LL SEE WHY THAT HAPPENED." "1887, THE TIME OF VICTORIA," "QUEEN OF ENGLAND AND EMPRESS OF INDIA." "LONDON IS THE WORLD CAPITAL OF COMMERCE." "ACROSS THE CHANNEL, IN GERMANY," "A CHILD NAMED ALBERT EINSTEIN CELEBRATES HIS 8th BIRTHDAY." "IT'S BEEN 23 YEARS" "SINCE JAMES CLERK MAXWELL STATED HIS EQUATIONS" "FOR ELECTROMAGNETIC RADIATION." "BEYOND THE ATLANTIC," "THE AMERICANS HAVE ENJOYED MORE THAN TWO DECADES" "OF PEACE AND PROSPERITY" "SINCE THEIR TERRIBLE CIVIL WAR ENDED." "WAVES OF MIGRANTS FROM EUROPE" "ARE SWELLING THE POPULATION OF THE UNITED STATES." "THE WESTERN FRONTIER IS BEING SETTLED" "AND SETTLING DOWN." "TODAY, 1887 SEEMS LIKE A TIME OF TRANQUILITY," "NOT ONLY IN COMMERCE AND POLITICS," "BUT ALSO IN SCIENCE." "MANY PHYSICISTS BELIEVED" "THAT ALL THE GREAT DISCOVERIES HAD BEEN MADE" "PHYSICS HAD REACHED A STATE OF PERFECTION" "THAT WAS POSITIVELY ETHEREAL." "IN FACT, THE CONCEPT OF THE ETHER" "WAS ONE OF ITS CENTRAL TENETS." "AND IN 1887," "IN CLEVELAND, OHIO," "TWO PHYSICISTS-- ALBERT ABRAHAM MICHELSON" "AND EDWARD W. MORLEY," "WERE PREPARING AN EXPERIMENT DESIGNED TO PROVE" "THAT THE ETHER REALLY EXISTED." "CERTAINLY, THE ETHER REALLY HAD EXISTED," "AT LEAST IN THE MINDS OF PHILOSOPHERS," "FOR THOUSANDS OF YEARS." "TODAY, WE CAN READILY ACCEPT" "THE IDEA OF SPACE AS A VACUUM," "VAST STRETCHES OF THE COSMOS VIRTUALLY DEVOID OF MATTER." "BUT TO THE ANCIENTS, THE CONCEPT OF A PERFECT VOID" "WAS IMPOSSIBLE TO GRASP." "SPACE HAD TO BE FILLED WITH SOMETHING, THEY THOUGHT." "THE SOLUTION THAT ARISTOTLE DEVISED WAS THE ETHER." "THAT WAS THE SUBSTANCE THAT FILLED" "WHAT WOULD OTHERWISE BE EMPTY SPACE." "BY THE 19th CENTURY, THE ETHER HAD COME TO SERVE" "MORE THAN A MERELY PHILOSOPHICAL NEED." "THE ETHER WAS THE MEDIUM" "THROUGH WHICH THE SUN'S LIGHT WAVES WOULD PROPAGATE" "TO NOURISH AND ILLUMINATE THE EARTH." "WAVES CAN PROPAGATE ALONG THE SURFACE OF WATER" "OR THROUGH A CRYSTAL" "OR THROUGH THE AIR OF A CONCERT HALL." "BUT ANY WAVE IS A DISTURBANCE" "THAT PASSES THROUGH A MEDIUM FROM ONE PART TO ANOTHER," "ON DOWN THE LINE." "IN OTHER WORDS, WHENEVER THERE'S A WAVE," "SOMETHING MUST BE WAVING." "BUT WHEN LIGHT WAVES FROM THE SUN REACH THE EARTH" "THROUGH APPARENTLY EMPTY SPACE, WHAT'S WAVING?" "IN THE 19th CENTURY," "THE ANSWER WAS AS CLEAR AS SPACE ITSELF." "IT WAS THE ETHER." "TO 19th-CENTURY PHYSICISTS," "THE ETHER WAS NOT ONLY REAL, IT HAD PHYSICAL PROPERTIES" "THAT COULD BE DEDUCED BY OBSERVING ITS BEHAVIOR." "FOR EXAMPLE," "THE SPEED OF ANY WAVE" "DEPENDS ON THE STIFFNESS" "OF THE MEDIUM THROUGH WHICH IT PASSES." "AND, OF COURSE, THE SPEED OF LIGHT IS ENORMOUS." "SO THE ETHER MUST BE VERY STIFF INDEED." "IN FACT, PHYSICISTS SAID," "IT WAS NEARLY IMPOSSIBLE TO COMPRESS IT." "ON THE OTHER HAND, THE EARTH AND OTHER PLANETS" "MOVED EASILY THROUGH THE INCOMPRESSIBLE ETHER," "OBEYING NEWTON'S LAWS" "AS IF THEY WEREN'T PASSING THROUGH ANY MEDIUM AT ALL." "IF THE ETHER BEHAVED LIKE A VISCOUS FLUID," "THE ORBITING PLANETS WOULD GRADUALLY LOSE ENERGY" "AND SPIRAL INWARD TOWARDS THE SUN." "SINCE THAT DIDN'T SEEM TO BE HAPPENING," "PHYSICISTS WERE ABLE TO REACH" "ANOTHER DEFINITE CONCLUSION ABOUT THE ETHER." "THE ETHER, THEY SAID, WAS A PERFECTLY MOBILE FLUID" "WITH NO VISCOSITY AT ALL." "IT WAS A TRANSPARENT," "PERFECTLY NONVISCOUS INCOMPRESSIBLE FLUID" "THAT FILLED ALL OF SPACE." "KNOWING SO MUCH ABOUT IT, THE ONLY JOB THAT REMAINED" "WAS TO DEMONSTRATE ITS EXISTENCE DIRECTLY" "IN A CLEAR AND IRREFUTABLE EXPERIMENT." "SOMEHOW THAT JOB HAD ELUDED THE GRASP OF PHYSICISTS" "THROUGHOUT THE CENTURY." "BUT IN 1887, ALBERT MICHELSON," "WITH THE HELP OF HIS FRIEND EDWARD MORLEY," "HAD DEVISED AN EXPERIMENT THAT COULDN'T FAIL." "AS FAR AS ACADEMIC CREDENTIALS GO," "MICHELSON WAS UNQUESTIONABLY QUALIFIED" "FOUR YEARS AT ANNAPOLIS," "EIGHT AT CLEVELAND'S CASE SCHOOL OF APPLIED SCIENCE," "AND THREE MORE YEARS" "AT CLARK UNIVERSITY IN WORCESTER, MASSACHUSETTS." "BUT IT WOULD TAKE MORE THAN TEACHING EXCELLENCE" "TO DETECT THE ABSOLUTE MOTION OF THE EARTH THROUGH SPACE," "WHICH, IN EFFECT, WOULD DETECT THE ETHER ITSELF." "IT WOULD TAKE AN EXTRAORDINARY EXPERIMENT" "WITH AN UNHEARD OF DEGREE OF ACCURACY." "FORTUNATELY, MICHELSON HAD AN ESTABLISHED TALENT" "FOR DESIGNING INSTRUMENTS THAT COULD MAKE" "THE MOST PRECISE MEASUREMENTS." "HIS EARLIER MEASUREMENTS OF THE SPEED OF LIGHT" "WERE BETTER THAN ANY BEFORE HIM." "WHEN HE WAS IN BERLIN," "MICHELSON DESIGNED A NEW INSTRUMENT" "THAT WAS EXQUISITELY PRECISE." "IT WAS CALLED AN INTERFEROMETER." "SHOWN HERE USING A LASER," "A MICHELSON INTERFEROMETER BEGINS" "BY SPLITTING A BEAM OF LIGHT INTO TWO BEAMS." "A PARTIALLY TRANSPARENT AND PARTIALLY REFLECTING MIRROR" "SENDS TWO BEAMS TRAVELING ON PERPENDICULAR PATHS." "EACH IS REFLECTED BACK TO THE POINT" "WHERE THEY HAD BEEN SPLIT IN TWO." "THERE, THEY COMBINE INTO A SINGLE BEAM AGAIN." "MICHELSON'S INTERFEROMETER CAN BE SEEN" "AS A RACE BETWEEN TWO LIGHT BEAMS." "IF THE RACE ENDS IN A TIE, THE RESULT IS A BRIGHT SPOT" "AT THE CENTER OF THE INTERFERENCE PATTERN." "BUT IN MICHELSON'S TIME," "THEY BELIEVED IT SHOULDN'T BE A TIE," "THAT IT SHOULDN'T EVEN BE A HORSE RACE." "THAT'S BECAUSE THE TWO BEAMS OF LIGHT" "WERE RACING ON A MOVING TRACK." "EVERYONE SUSPECTED THE EARTH" "AND THEREFORE THE INTERFEROMETER" "WERE MOVING THROUGH THE ETHER." "THE BEAMS SHOULD TRACE OUT QUITE DIFFERENT PATHS" "WITH RESPECT TO THE ETHER." "THE BEAM MOVING SIDEWAYS TO THE EARTH'S MOTION" "MAKES A TRIANGLE," "WHILE THE ONE MOVING ALONG THE MOTION" "HAS LESS DISTANCE TO GO ONE WAY," "BUT MORE THE OTHER." "ON THEIR ROUND TRIPS," "THE BEAM ALONG THE DIRECTION OF MOTION" "HAS A LITTLE FARTHER TO GO." "SO THE SIDEWAYS BEAM SHOULD ALWAYS WIN." "MICHELSON KNEW THAT THE EXPECTED DIFFERENCE" "IN THE ARRIVAL OF THE TWO BEAMS WOULD BE VERY SMALL." "AFTER ALL, THE SPEED OF LIGHT" "IS 3 x 10 TO THE 8th METERS PER SECOND," "WHILE EARTH'S SPEED THROUGH THE ETHER" "IS ONLY 3 x 10 TO THE 4th METERS PER SECOND." "SINCE THE TWO BEAMS" "WENT FORWARD AND BACK BEFORE BEING COMPARED," "THEIR TIME DIFFERENCE WOULD DEPEND" "ON THE SQUARE OF THAT RATIO." "IT WOULD BE A DIFFERENCE OF ONLY 1 PART IN 100 MILLION." "IRONICALLY, THAT TINY DIFFERENCE IN TRAVEL TIME" "WOULD BE THE EXACT PROOF" "GALILEO DESPERATELY NEEDED THREE CENTURIES EARLIER" "THE ABSOLUTE, CONCRETE PROOF HE NEEDED" "TO SHOW THAT COPERNICUS HAD BEEN RIGHT," "AND THAT THE EARTH REALLY MOVES AROUND THE SUN." "PERHAPS GALILEO COULD HAVE WON HIS CASE" "IF HE'D HAD REAL SCIENTIFIC PROOF" "THAT THE EARTH MOVES." "ALTHOUGH IT'S DOUBTFUL THAT HE HAD GALILEO IN MIND," "THAT TINY DIFFERENCE IN THE TRAVEL TIME" "OF THE TWO BEAMS OF LIGHT" "WAS WHAT MICHELSON WANTED TO MEASURE IN BERLIN IN 1880." "A GERMAN INSTRUMENT-MAKING FIRM" "BUILT THE FIRST INTERFEROMETER." "IN 1881, WHEN MICHELSON WENT TO POTSDAM," "HE TOOK IT WITH HIM." "IT WAS SENSITIVE, ALL RIGHT." "SO SENSITIVE THAT HORSE-DRAWN WAGONS," "EVEN PEDESTRIANS ON THE STREET OUTSIDE HIS LAB," "AFFECTED HIS MEASUREMENTS." "EACH TIME HE TRIED," "IT TOOK ALMOST A DAY TO GET A SINGLE MEASUREMENT." "SO WHEN MICHELSON SAW NO "ETHER EFFECT"" "IN HIS MEASUREMENTS, HE WASN'T CONCERNED." "HE THOUGHT, CORRECTLY," "THAT HIS INSTRUMENT WASN'T DEPENDABLE ENOUGH." "TIME PASSED, AND MICHELSON DID NO MORE" "WITH THE INTERFEROMETER." "HE RETURNED TO THE UNITED STATES" "AND TOOK A POSITION WITH CASE INSTITUTE IN CLEVELAND." "DURING THAT PERIOD, HE AND EDWARD W. MORLEY," "A PHYSICIST AND CHEMIST AT WESTERN RESERVE UNIVERSITY," "BECAME COLLEAGUES AND CLOSE FRIENDS." "OTHER PHYSICISTS, MEANWHILE," "URGED HIM TO TRY AGAIN TO DETECT THE ETHER." "SO IN 1887, MICHELSON ASKED HIS FRIEND MORLEY" "TO WORK WITH HIM" "ON A NEW AND HIGHLY SENSITIVE INTERFEROMETER." "THE NEW INTERFEROMETER WAS 10 TIMES MORE SENSITIVE" "THAN HIS 1880 INSTRUMENT." "MICHELSON HAD BEEN THINKING OF WAYS" "TO MAKE THE INTERFEROMETER STEADY" "AND NOT SUSCEPTIBLE TO PASSING CARTS AND PEOPLE." "THE MIRRORS RESTED ON AN ENORMOUS BASE OF SANDSTONE" "THAT FLOATED IN A POOL OF MERCURY." "WHEN MICHELSON AND MORLEY TESTED THE NEW INTERFEROMETER," "THEY WERE THRILLED AND DELIGHTED." "THE INSTRUMENT HAD ALL THE STABILITY AND SENSITIVITY" "THEY HAD HOPED FOR AND SHOULD BE ABLE, EASILY," "TO DETECT THE TINY EXPECTED DIFFERENCE IN TRAVEL TIME" "OF THE TWO BEAMS OF LIGHT" "DUE TO MOTION THROUGH THE ETHER." "THE ACTUAL EXPERIMENT WAS TO BE DONE" "BY OBSERVING THE INTERFERENCE PATTERN" "WITH THE INTERFEROMETER IN ONE ORIENTATION" "WITH RESPECT TO THE MOTION THROUGH THE ETHER..." "AND THEN ROTATING IT." "IF THE TWO BEAMS ARRIVED IN A TIE, FOR EXAMPLE," "CONSTRUCTIVE INTERFERENCE WOULD MAKE A BRIGHT SPOT" "AT THE CENTER OF THE PATTERN." "BUT IF ONE BEAM ARRIVED SLIGHTLY AHEAD OF THE OTHER," "DESTRUCTIVE INTERFERENCE COULD MAKE THE CENTER DARK." "THE EFFECT OF MOTION THROUGH THE ETHER" "WOULD BE SEEN IN THE SHIFT OF THE INTERFERENCE FRINGES" "AS THE INSTRUMENT WAS ROTATED." "TO THE COMPLETE SURPRISE OF MICHELSON AND MORLEY" "AND JUST ABOUT EVERYONE ELSE," "THERE WAS NO SHIFT AT ALL IN THE FRINGES," "WHICH MEANS THERE WAS NO DELAY." "NOTHING." "NO DIFFERENCE AT ALL." "NO MATTER HOW THEY VARIED THE EXPERIMENT," "SUMMER OR WINTER, NIGHT OR DAY," "THE RESULT WAS THE SAME." "LIGHT APPARENTLY TRAVELS AT THE SAME SPEED" "IN ALL DIRECTIONS," "IN COMPLETE DISAGREEMENT WITH THE IDEA OF EARTH" "MOVING THROUGH THE ETHER." "FOR THE NEXT 50 YEARS, NUMEROUS PHYSICISTS REPEATED" "THE MICHELSON-MORLEY EXPERIMENT" "WITH EVER-INCREASING PRECISION AND SOPHISTICATION" "IN THE VAIN HOPE OF FINDING SOME MISTAKE." "BUT EVEN IN 1887, THE FACTS WERE CLEAR." "THE EXPERIMENT HAD FAILED TO DETECT THE ETHER," "AND THE CONSEQUENCES WERE SHATTERING." "THE NEGATIVE RESULT" "WAS ALMOST AS DISTURBING FOR MICHELSON" "AS IT WAS FOR PHYSICS AS A WHOLE." "HE TRULY BELIEVED THE ETHER EXISTED," "AND THAT HE AND MORLEY HAD SIMPLY FAILED TO DETECT IT." "SUSTAINED BY A LEGENDARY SENSE OF HUMOR," "MICHELSON CARRIED ON THROUGH THE YEARS," "AND HE CONTINUED TO SUCCEED" "AS A VIRTUOSO OF EXPERIMENTAL PHYSICS." "NONETHELESS, HE REMAINED HAUNTED BY THE RESULTS" "OR THE LACK OF THEM" "IN HIS EXPERIMENT WITH EDWARD MORLEY." "PUTTING THE IDEA OF THE ETHER IN HISTORICAL PERSPECTIVE," "IT HAD BEEN IMPORTANT BEYOND MEASURE." "IN 1887, ITS EXISTENCE WAS AS IMPORTANT" "AS IN COPERNICUS' DAY THE SUN'S LOCATION." "NO EXPERIMENT HAD BEEN BETTER CONCEIVED" "NOR MORE CAREFULLY EXECUTED." "IN SCIENCE, WHEN SUCH AN EXPERIMENT FAILS," "IT NOT ONLY CREATES A THEORETICAL DILEMMA," "IT CAN PROVOKE FANTASTIC RESPONSES" "IN THE SCIENTIFIC COMMUNITY." "IN 1892, THE IRISH PHYSICIST G.F. FITZGERALD" "SUGGESTED THAT THE SIZE OF ONE ARM" "OF THE MICHELSON AND MORLEY INTERFEROMETER" "MIGHT HAVE SOMEHOW CONTRACTED." "HOW MUCH IT CONTRACTED, HE SAID," "DEPENDED ON ITS VELOCITY." "TO MOST PHYSICISTS," "FITZGERALD'S CONTRACTION SOUNDED ABSURD." "BUT NOT TO EUROPE'S MOST DISTINGUISHED PHYSICIST," "H.A. LORENTZ." "HE WORKED OUT A QUANTITATIVE MODEL" "TO EXPLAIN THE PHENOMENON," "AND IN THE PROCESS, DEVELOPED MATHEMATICAL EXPRESSIONS" "THAT WOULD CHANGE THE FACE OF PHYSICS." "THEY CAME TO BE CALLED "THE LORENTZ TRANSFORMATIONS."" "IN 1899, THE GREAT FRENCH MATHEMATICIAN HENRI POINCARE" "EXAMINED THE RESULTS OBTAINED BY MICHELSON AND MORLEY." "HE OFFERED A GENERAL EXPLANATION," "CALLING IT THE PRINCIPLE OF RELATIVITY." "IT WAS THE IDEA THAT ABSOLUTE MOTION" "WILL NEVER BE DETECTED IN THE LABORATORY." ""THERE MUST ARISE" "AN ENTIRELY NEW KIND OF DYNAMICS," HE SAID." "POINCARE WAS RIGHT." "AN ENTIRELY NEW KIND OF DYNAMICS WOULD ARISE," "BUT THE PRINCIPLE OF RELATIVITY," "WHICH WOULD BE ITS CORNERSTONE, WAS FAR FROM NEW." "IT WENT BACK AT LEAST AS FAR AS GALILEO GALILEI." "GALILEO HAD SAID THAT AN OBJECT IN MOTION" "WOULD TEND TO REMAIN" "IN THAT STATE OF UNIFORM MOTION." "THAT WAS THE LAW OF INERTIA." "IT WAS CORRECT BECAUSE," "IN ITS OWN FRAME OF REFERENCE," "EVERY STATE OF UNIFORM MOTION WAS A STATE OF REST." "GALILEO UNDERSTOOD THE LAW OF INERTIA" "AND WHY IT WAS TRUE." "THERE IS NO DIFFERENCE AT ALL" "BETWEEN BEING AT REST" "AND BEING IN UNIFORM MOTION." "BUT ON THE OTHER HAND," "ALBERT MICHELSON, IN HIS EXPERIMENT," "HAD SET OUT TO DETECT" "THE ABSOLUTE MOTION OF THE EARTH." "HAD HE SUCCEEDED, HE WOULD HAVE PROVED" "THAT THERE IS A DIFFERENCE BETWEEN MOTION AND REST," "A DIFFERENCE THAT CAN BE DETECTED IN AN EXPERIMENT." "THE TRUTH IS THAT, EITHER WAY, SUCCESS OR FAILURE," "THE RESULTS OF MICHELSON'S EXPERIMENT" "WOULD HAVE FACED PHYSICS WITH A GRAVE DILEMMA." "AS IT TURNED OUT, THE DILEMMA WAS ALMOST BEYOND IMAGINING" "EVEN TO THE IMAGINATION OF HENDRIK LORENTZ." "OF COURSE, WE CAN IMAGINE LORENTZ, IF WE CHOOSE," "AS A PITCHER FOR THE BROOKLYN DODGERS." "SUPPOSE HE HAD BEEN CAPABLE OF LAUNCHING A FASTBALL" "AT 6/10 THE SPEED OF LIGHT" "WHILE ROLLING PAST ALBERT" "AT THE SAME SPEED." "SURELY, FAST AS HENRY'S PITCH HAD BEEN," "IT WOULD SEEM MUCH FASTER TO ALBERT." "BUT--AND HERE'S WHAT" "THE MICHELSON-MORLEY EXPERIMENT SAID" "IF BOTH ALBERT AND HENRY WATCHED THE SAME LIGHT BEAM," "EACH WOULD THINK IT WAS TRAVELING" "AT THE SPEED OF LIGHT RELATIVE TO HIMSELF," "EVEN THOUGH THEY WERE MOVING RELATIVE TO EACH OTHER." "SUCH MIND-BOGGLING CONSEQUENCES WERE HARD TO ACCEPT," "EVEN FOR A MIND SUCH AS THAT OF HENDRIK LORENTZ." "HE WORKED OUT A MATHEMATICAL THEORY" "THAT ACCOUNTED FOR THE EXPERIMENT," "BUT IT WAS BASED ON" "THE MYSTERIOUS, UNVERIFIED PROPERTIES" "OF A NEWLY DISCOVERED PARTICLE CALLED THE ELECTRON." "IT TOOK A YOUNGER MAN, A FRESH POINT OF VIEW," "TO SEE THE SPEED OF LIGHT IN AN ENTIRELY NEW LIGHT." "HIS NAME WAS ALBERT EINSTEIN." "IN PHYSICS, HIS WAS THE WAY OF THE FUTURE." "BUT NO ONE HAD DONE MORE" "TO ILLUMINATE THAT FUTURE THAN ALBERT MICHELSON HIMSELF." "FOR NEARLY 50 YEARS AFTER HIS FIRST INTERFEROMETER," "HE LIVED ON, MEASURING THE SPEED OF LIGHT" "WITH EVER INCREASING PRECISION," "MEASURING A STAR'S DIAMETER FOR THE FIRST TIME EVER," "AND EVEN ADMITTING, FINALLY," "THAT HIS INTERFEROMETER EXPERIMENT" "HAD VERIFIED ALBERT EINSTEIN'S THEORY OF RELATIVITY." "...THEMEASUREMENTOF  THEVELOCITYOF LIGHT." "THESECOND,AMEASUREMENT OFTHEDIAMETEROFA STAR ," "ANDTHETHIRDWAS ATEST" "OFTHEEINSTEINTHEORY OFRELATIVITY." "MICHELSON WON THE RESPECT OF THE SCIENTIFIC COMMUNITY," "THE FRIENDSHIP OF ALBERT EINSTEIN," "AND BECAME THE FIRST AMERICAN" "TO WIN THE NOBEL PRIZE." "BUT TO THE END OF HIS DAYS," "HE NEVER FULLY ACCEPTED" "THE IMPLICATIONS OF HIS FAMOUS EXPERIMENT." ""IT MUST BE ADMITTED," HE CONFESSED IN 1931," ""THESE EXPERIMENTS ARE NOT SUFFICIENT" "TO JUSTIFY THE HYPOTHESIS OF AN ETHER."" ""BUT THEN," HE WONDERED," ""HOW CAN THE NEGATIVE RESULTS BE EXPLAINED?"" "ON THE SURFACE," "LIKE UNINTENTIONAL SHADOWS ON A CANVAS," "THERE ARE DARK AREAS" "IN THE LIFE OF ALBERT ABRAHAM MICHELSON." "FOR DESPITE ALL THE BRIGHT SPOTS" "IN A CAREER OF 50 YEARS," "HE TENDED TO FOCUS ON HIS SO-CALLED FAILURE OF 1887." ""SINCE THE RESULT OF THE ORIGINAL EXPERIMENT" "WAS NEGATIVE," HE CONCLUDED," ""THE PROBLEM IS STILL DEMANDING A SOLUTION."" "BUT IN REALITY, MICHELSON'S EXPERIMENT," "IF IT WAS A FAILURE," "WAS THE MOST BRILLIANT FAILURE IN ALL THE HISTORY OF SCIENCE." "AND THE SOLUTION HE SOUGHT BUT REFUSED TO ACCEPT" "ALBERT EINSTEIN'S THEORY OF RELATIVITY" "WOULD CHANGE FOREVER THE VERY MEANING OF SPACE AND TIME." "WE OFTEN TEACH PHYSICS IN A HISTORICAL WAY." "THE PURPOSE, OF COURSE, IS TO TEACH PHYSICS." "VERY OFTEN, WE REDESIGN THE HISTORY." "WE TELL YOU NOT WHAT REALLY HAPPENED," "BUT WHAT SHOULD HAVE HAPPENED." "WELL, I SUPPOSE IT SERVES" "SOME PEDAGOGICAL PURPOSE TO DO THAT," "SO LET ME TELL YOU WHAT SHOULD HAVE HAPPENED." "A PATENT CLERK IN SWITZERLAND NAMED ALBERT EINSTEIN" "SHOULD HAVE SAID, "LOOK, THE MICHELSON-MORLEY EXPERIMENT" ""COMPELS US TO DO TWO THINGS." ""ONE IS TO RESTORE THE PRINCIPLE OF RELATIVITY." ""THE OTHER ONE IS TO BELIEVE THAT THE SPEED OF LIGHT" ""WILL BE THE SAME TO ALL OBSERVERS," ""REGARDLESS OF THEIR STATE OF MOTION." ""AND FROM THOSE TWO FUNDAMENTAL POSTULATES" ""FOLLOW ALL THE ASTONISHING RESULTS" "OF THE THEORY OF RELATIVITY."" "NOW LET ME TELL YOU WHAT THE FACTS WERE." "ONE IS THAT MICHELSON NEVER, FOR THE REST OF HIS LIFE," "BELIEVED THE RESULTS OF HIS OWN EXPERIMENT." "THE OTHER ONE IS THAT EINSTEIN" "NOT ONLY DIDN'T BASE HIS THEORY" "ON THE MICHELSON-MORLEY EXPERIMENT," "BUT WHEN HE WROTE HIS FAMOUS PAPER IN 1905," "HE CLAIMED HE NEVER HEARD OF THE MICHELSON-MORLEY EXPERIMENT." "WE'LL SEE WHY NEXT TIME." 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