Albert A. Michelson Biographical A lbert Abraham Michelson was born in Strelno, Prussia, on December 19, Two years later his family emigrated to the United States to settle at Virginia City, Nevada, but they eventually moved to San Francisco where Michelson received his early education in public schools, matriculating from the High School in A.A. Michelson, in full Albert Abraham Michelson, (born December 19, , Strelno, Prussia [now Strzelno, Poland]—died May 9, , Pasadena, California, U.S.), German-born American physicist who established the speed of light as a fundamental constant and pursued other spectroscopic and metrological investigations.
He received the Nobel Prize for Physics. Michelson came to the United States with his parents when he was two years old. At age alebrt Michelson entered the United States Naval Academy at Annapolis, Maryland, where he what did albert michelson describe well in science but was rather below average in seamanship.
He graduated in and served as science instructor at the academy from until In Michelson began work on what was to be the fid of his life, the accurate measurement of the speed of light. He was able to obtain useful values with homemade apparatuses.
Feeling the need to study optics before he could be qualified to make real progress, he traveled to Europe in and spent two years in Berlin, Heidelberg, and Paris, resigning from the U. Navy in Upon his return to the United States, he determined the velocity of light to bekmmiles per second, a value that remained the best for a generation, until Michelson bettered it.
While in Europe, Michelson began constructing an interferometera device designed to split a beam of light in two, send the parts along perpendicular paths, then bring them back together.
If the light waves had, in the interimfallen how to find bank account number rbc of step, interference fringes of alternating light and dark bands would be obtained. From the width and number of those fringes, unprecedentedly delicate measurements could be made, comparing the velocity of light rays what did albert michelson describe at right angles to each other.
His earliest experiments in Berlin showed no interference fringes, however, which seemed to signify that there what did albert michelson describe no difference in the speed of the light rays and, therefore, no Earth motion relative to the ether.
In he accepted a position as professor of physics at the Case School of Applied Science in Cleveland and there concentrated his efforts on improving the delicacy of his interferometer experiment.
Bywith the help of his colleague, American chemist Edward Williams Morleyhe was ready whhat announce the results of what has since come to be called the Michelson-Morley experiment. Those results were still negative; there were no interference fringes and apparently no motion of Earth relative to the ether. It was perhaps the most significant negative experiment in the history of science. In terms of classical Newtonian physics, the results were paradoxical. Evidently, the speed of light plus any other added velocity was still equal only to the speed of light.
In Michelson—after serving as professor of physics at Clark University at WorcesterMassachusetts albertt, from —was appointed professor and the first head of the department of physics at the newly organized University of Chicagoa position he held until his retirement in From to he served as president of the National Academy of Sciences.
In he became the first American ever to receive a Nobel Prize in the sciences, for his spectroscopic and metrological investigations, the first of many honours he was to receive. Michelson advocated using some particular wavelength of light as a standard what happens when you turn your cellular data off distance a suggestion generally accepted in and, inmeasured the standard metre in terms of the red light emitted by heated cadmium.
His interferometer made it possible for him to determine the width of heavenly objects by matching the light rays from the two sides and noting the interference fringes that resulted.
Inusing a 6-metre foot interferometer attached to dsscribe cm inch telescope, he succeeded in measuring the diameter of the star Betelgeuse Alpha Orionis as , km times the diameter of the Sun.
This was the first substantially accurate determination of the size of a star. In Michelson returned to the problem of the accurate measurement of the velocity of light.
In the California mountains he surveyed a km pathway between two mountain peaks, determining the distance to an accuracy of less than 2. To refine matters further, he made use of a long, evacuated tube through which a light beam was reflected back and forth until it had traveled 16 km through a vacuum.
Michelson Article Media Additional Info. Home Science Physics Physicists A. Michelson American scientist. Print Cite descgibe Cite. While every effort has been made to follow citation style rules, there albret be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
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Professor of Biochemistry, Boston University, alberr See Article History. Alternative Title: Albert Abraham Michelson. Get a Britannica Premium subscription and gain access to exclusive content. Subscribe Now. Learn More in these related Britannica articles:. Michelson in while he was studying with Hermann von Helmholtz in Berlin for the purpose of measuring the effect on the speed of light of the motion of the ether through which light was believed to travel see below The electromagnetic wave….
Michelson set out to measure this effect and, as noted above, designed for this purpose the interferometer sketched in Figure 4. History at your fingertips. Sign up here to see what happened On This Day what we talk about when we talk about love analysis, what did albert michelson describe day in your inbox!
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The nineteenth century physicist, Albert Abraham Michelson, was the first American to be awarded a Nobel Prize in Physics. He became famous for his establishment of the speed of light as a fundamental constant and other spectroscopic and meteorological investigations.
He was the founder and the first head of the physics department of the University of Chicago. He grew up in the mining towns of Murphy's Camp , California and Virginia City, Nevada , where his father was a merchant. His family was Jewish by birth but non-religious, and Michelson himself was a lifelong agnostic.
President Ulysses S. Grant awarded Michelson a special appointment to the U. Naval Academy in After graduating in and two years at sea, he returned to the Naval Academy in to become an instructor in physics and chemistry until In the following year he obtained leave of absence to continue his studies in Europe.
Michelson was fascinated with the sciences, and the problem of measuring the speed of light in particular. While at Annapolis , he conducted his first experiments on the speed of light , as part of a class demonstration in In he accepted a position as professor of physics at the Case School of Applied Science in Cleveland , Ohio and concentrated on developing an improved interferometer. In he and Edward Morley carried out the famous Michelson—Morley experiment which failed to detect evidence of the existence of the luminiferous ether.
He later moved on to use astronomical interferometers in the measurement of stellar diameters and in measuring the separations of binary stars.
In Michelson became a professor at Clark University at Worcester , Massachusetts and in was appointed professor and the first head of the department of physics at the newly organized University of Chicago. In , Michelson had the honor of being the first American to receive a Nobel Prize in Physics "for his optical precision instruments and the spectroscopic and metrological investigations carried out with their aid".
A crater on the Moon is named after him. Michelson died in Pasadena, California at the age of Case Western Reserve has dedicated a Michelson House to him, and Michelson Hall an academic building of science classrooms, laboratories and offices at the United States Naval Academy also bears his name. There is a display in the publicly accessible area of the Lab which includes facsimiles of Michelson's Nobel Prize medal, the prize document, and examples of his diffraction gratings.
In , a newly renovated physics research center at the University of Chicago was renamed in honor of Michelson as well. Numerous awards, lectures, and honors have been created in Albert A. Michelson's name. Naval Academy. In Michelson married Margaret Hemingway, daughter of a wealthy New York stockbroker and lawyer and the niece of his commander William T.
They had two sons and a daughter. In , he married Edna Stanton. They raised three daughters. Michelson was fascinated by light all his life. He conducted some preliminary measurements using largely improvised equipment in , about the same time that his work came to the attention of Simon Newcomb , director of the Nautical Almanac Office who was already advanced in planning his own study.
Michelson's formal experiments took place in June and July He constructed a frame building along the north sea wall of the Naval Academy to house the machinery. Thus began a long professional collaboration and friendship between the two. In , a novel electrical method was used by E. Though this result has subsequently been shown to be severely biased by the poor electrical standards in use at the time, it seems to have set a fashion for rather lower measured values.
From , Michelson started planning a definitive measurement from the Mount Wilson Observatory , using a baseline to Lookout Mountain , a prominent bump on the south ridge of Mount San Antonio "Old Baldy" , some 22 miles distant. In , the U. Coast and Geodetic Survey began two years of painstaking measurement of the baseline using the recently available invar tapes.
Famous as the measurement is, it was beset by problems, not least of which was the haze created by the smoke from forest fires which blurred the mirror image. It is also probable that the intensively detailed work of the geodetic survey , with an estimated error of less than one part in 1 million, was compromised by a shift in the baseline arising from the Santa Barbara earthquake of June 29, , which was an estimated magnitude of 6.
The now-famous Michelson—Morley experiment also influenced the affirmation attempts of peer Albert Einstein 's theory of general relativity and special relativity , using similar optical instrumentation. These instruments and related collaborations included the participation of fellow physicists Dayton Miller , Hendrik Lorentz , and Robert Shankland.
The period after marked the advent of new measurements of the speed of light using novel electro-optic devices, all substantially lower than Michelson's value. Michelson sought another measurement, but this time in an evacuated tube to avoid difficulties in interpreting the image owing to atmospheric effects.
In , he began a collaboration with Francis G. Pease and Fred Pearson to perform a measurement in a 1. For the first time in history the speed of light was measured in an almost perfect vacuum of 0. For instance, he adopted a steel measuring tape with a said length of feet and he intended to measure tens of times across the distance; still, he measured its length against a copy of the official standard yard to find out it as Aside from the efforts to reduce as much as possible the systematic errors, repeated measurements were performed at multiple levels to obtain more accurate results.
MacKay and R. To realize that, he also strived to have each measurement not influencing each other, thus being mutually independent random variables. It should also be noted about the statistical model for repeated measurements where the assumption of independence or identical distributions is unrealistic.
In the case of light speed study, each measurement is approached as the sum of quantity of interest and measurement error. In the absence of systematic error, the measurement error of speed of light can be modeled by a random sample from a distribution with unknown expectation and finite variance; thus, the speed of light is represented by the expectation of the model distribution and the ultimate goal is to estimate the expectation of the model distribution on the acquired dataset.
The law of large numbers suggests to estimate the expectation by the sample mean. Their experiment for the expected motion of the Earth relative to the aether , the hypothetical medium in which light was supposed to travel, resulted in a null result. Surprised, Michelson repeated the experiment with greater and greater precision over the next years, but continued to find no ability to measure the aether.
The Michelson—Morley results were immensely influential in the physics community, leading Hendrik Lorentz to devise his now-famous Lorentz contraction equations as a means of explaining the null result.
There has been some historical controversy over whether Albert Einstein was aware of the Michelson—Morley results when he developed his theory of special relativity , which pronounced the aether to be "superfluous. I guess I just took it for granted that it was true. The precision of their equipment allowed Michelson and Morley to be the first to get precise values for the fine structure in the atomic spectral lines  for which in Arnold Sommerfeld gave a theoretical explanation, introducing the fine-structure constant.
In Michelson and Francis G. Pease made the first measurement of the diameter of a star other than the Sun. Michelson had invented astronomical interferometry and built such an instrument at the Mount Wilson Observatory which was used to measure the diameter of the red giant Betelgeuse. A periscope arrangement was used to direct light from two subpupils, separated by up to 20 feet 6m , into the main pupil of the inch 2.
The measurement of stellar diameters and the separations of binary stars took up an increasing amount of Michelson's life after this. Beginning in the s, astronomical interferometry was revived, with the configurations using two or more separate apertures with diameters small compared to their separation being often referred to as "Michelson Stellar Interferometry. Michelson's concept of interfering light from two relatively small apertures separated by a substantial distance but with that distance, or baseline , now often as long as hundreds of meters is employed at modern operational observatories such as VLTI , CHARA and the U.
Navy's NPOI. Gravitational waves are detected using a Michelson interferometer with a laser light source. In there were three Michelson interferometer gravitational wave detectors operational, and a fourth under construction.
These Michelson interferometers have arms 4 kilometers in length, set at 90 degree angles to each other, with the light passing through 1 m diameter vacuum tubes running their entire length. A passing gravitational wave will slightly stretch one arm as it shortens the other. This is precisely the motion to which these Michelson interferometers are most sensitive. As of fifteen gravitational wave events had been observed using these Michelson interferometers. Naval Academy , despite the opposition of the bigoted town schoolteacher played by William Schallert.
Bonanza was set in and around Virginia City, Nevada , where Michelson lived with his parents prior to leaving for the Naval Academy. In a voice-over at the end of the episode, Greene mentions Michelson's Nobel Prize. His aunt Bertha Meyers owned a house on Main Street toward the east end of town and Michelson probably visited her family there frequently. New Beast Theater Works in collaboration with High Concept Laboratories produced a 'semi-opera' about Michelson, his obsessive working style and its effect on his family life.
Michelson was portrayed by Jon Stutzman. The play was directed by David Maral with music composed by Joshua Dumas. Alan Weltzien, , it is an appreciation of Michelson from Maclean's vantage point as a graduate student regularly watching him play billiards.
The Computer Measurement Group gives an annual A. Michelson Award. From Wikipedia, the free encyclopedia. American physicist — Not to be confused with the athlete Albert Michelsen.
Strzelno , Kingdom of Prussia now Poland. Pasadena, California , U. Margaret Hemingway. Edna Stanton. This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources.
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