Albert Michelson

16 results back to index

pages: 492 words: 149,259

Big Bang by Simon Singh


Albert Einstein, Albert Michelson, All science is either physics or stamp collecting, Andrew Wiles, anthropic principle, Arthur Eddington, Astronomia nova, Brownian motion, carbon-based life, Cepheid variable, Chance favours the prepared mind, Commentariolus, Copley Medal, cosmic abundance, cosmic microwave background, cosmological constant, cosmological principle, dark matter, Dava Sobel, Defenestration of Prague, Dmitri Mendeleev, Edmond Halley, Edward Charles Pickering, Eratosthenes, Ernest Rutherford, Erwin Freundlich, Fellow of the Royal Society, fudge factor, Hans Lippershey, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, Henri Poincaré, horn antenna, if you see hoof prints, think horses—not zebras, Index librorum prohibitorum, invention of the telescope, John von Neumann, Karl Jansky, Louis Daguerre, Louis Pasteur, luminiferous ether, Magellanic Cloud, music of the spheres, Olbers’ paradox, On the Revolutions of the Heavenly Spheres, Paul Erdős, retrograde motion, scientific mainstream, Simon Singh, Solar eclipse in 1919, Stephen Hawking, the scientific method, Thomas Kuhn: the structure of scientific revolutions, unbiased observer, V2 rocket, Wilhelm Olbers, William of Occam

We believe it is a real thing, with great rigidity in comparison with its density: it may be made to vibrate 400 million million times per second; and yet be of such density as not to produce the slightest resistance to any body going through it. In other words, the ether was incredibly strong, yet strangely insubstantial. It was also transparent, frictionless and chemically inert. It was all around us, yet it was clearly hard to identify because nobody had ever seen it, grabbed it or bumped into it. Nevertheless, Albert Michelson, America’s first Nobel Laureate in physics, believed that he could prove its existence. Michelson’s Jewish parents had fled persecution in Prussia in 1854, when he was just two years old. He grew up and studied in San Francisco before going on to join the US Naval Academy, where he graduated a lowly twenty-fifth in seamanship, but top in optics. This prompted the Academy’s superintendent to remark: ‘If in the future you’d give less attention to those scientific things and more to your naval gunnery, there might come a time when you would know enough to be of some service to your country.’

The swimmers race in the following way: they both start at the same point on one bank. One swims directly across the river to the closest point on the opposite bank, then turns around and swims back. The other stays on one side of the river, swimming downstream a distance (measured along the bank) exactly equal to the width of the river, then swims back to the start. Who wins? [See Figure 20 for the solution.] Figure 20 Albert Michelson used this swimming puzzle to explain his ether experiment. The two swimmers play the same role as the two beams of light heading in perpendicular directions, then both returning to the same starting point. One swims first with and then against the current, while the other swims across the current – just as one light beam travels with and against the ether wind, and the other across it. The puzzle is to work out the winner of a race over a distance of 200 feet between two swimmers who both can swim at 5 feet per second in still water.

He took great pride in the profession that had made the Hubbies a respectable middle-class family: ‘The best definition we have found for civilisation is that a civilised man does what is best for all, while the savage does what is best for himself. Civilisation is but a huge mutual insurance company against human selfishness.’ Edwin resolved the conflict between his own ambition and his father’s pragmatism by formally studying law to pacify his father, while also completing enough courses in physics to keep alive his dream of becoming an astronomer. The Chicago physics department was headed by Albert Michelson, who had dispensed with the ether and won America’s first Nobel Prize for Physics in 1907. The university was also home to Robert Millikan, who would go on to become America’s second Nobel Laureate in physics, and who took on Hubble as his part-time laboratory assistant while Edwin was still an undergraduate. This was a brief but pivotal relationship, because Millikan helped to propel Hubble towards his next goal, a Rhodes scholarship to study at Oxford University.


pages: 208 words: 70,860

Paradox: The Nine Greatest Enigmas in Physics by Jim Al-Khalili


Albert Einstein, Albert Michelson, anthropic principle, Arthur Eddington, butterfly effect, clockwork universe, complexity theory, dark matter, Edmond Halley, Edward Lorenz: Chaos theory, Ernest Rutherford, Henri Poincaré, invention of the telescope, luminiferous ether, Magellanic Cloud, Olbers’ paradox, Schrödinger's Cat, Schrödingers cat, Search for Extraterrestrial Intelligence, The Present Situation in Quantum Mechanics, Wilhelm Olbers

And since no one had seen such a medium, they had to try to come up with an experiment to detect it. It was labeled the luminiferous (“light-carrying”) ether and a major effort was made to prove its existence. Of course, it had to have certain properties: for instance, it had to permeate the whole galaxy in order for distant starlight to reach us through the vacuum of space. In 1887, at a college in Ohio, two American physicists, Albert Michelson and Edward Morley, conducted one of the most famous experiments in the history of science. They had devised a method for measuring very accurately the time it takes for a light beam to cover a fixed distance. But before I describe what they found, there is another property of waves that I need to mention, which is that the speed at which waves travel does not depend on how fast their source is moving.

The Michelson-Morley result was the equivalent of both you on board the moving train and the observer watching the train go by agreeing on how fast the passenger was moving! It sounds ridiculous, right? Surely, as I explained before, you see the passenger moving at walking pace while the platform observer sees him whizz past at train speed, plus a little more. Just eight years before Michelson and Morley achieved their disturbing finding, Albert Einstein had been born in Ulm in Germany. That same year, 1879, Albert Michelson, working at a U.S. Naval Observatory in Washington, had measured the speed of light to an accuracy of about one part in ten thousand. He wasn’t the first to do this and would not be the last, but it would stand him in good stead when he and Morley conducted their famous experiment. As for the young Einstein, although of course he was completely unaware of the astonishing result that Michelson and Morley announced to the world, he was nevertheless soon pondering the unusual properties of light himself by devising imaginary experiments.


pages: 654 words: 204,260

A Short History of Nearly Everything by Bill Bryson


Albert Einstein, Albert Michelson, Alfred Russel Wallace, All science is either physics or stamp collecting, Arthur Eddington, Barry Marshall: ulcers, Brownian motion, California gold rush, Cepheid variable, clean water, Copley Medal, cosmological constant, dark matter, Dava Sobel, David Attenborough, Drosophila, Edmond Halley, Ernest Rutherford, Fellow of the Royal Society, Harvard Computers: women astronomers, James Watt: steam engine, John Harrison: Longitude, Kevin Kelly, Kuiper Belt, Louis Pasteur, luminiferous ether, Magellanic Cloud, Menlo Park, Stephen Hawking, supervolcano, Thomas Malthus, Wilhelm Olbers

Gibbs's Equilibrium has been called “the Principia of thermodynamics,” but for reasons that defy speculation Gibbs chose to publish these landmark observations in the Transactions of the Connecticut Academy of Arts and Sciences, a journal that managed to be obscure even in Connecticut, which is why Planck did not hear of him until too late. Undaunted—well, perhaps mildly daunted—Planck turned to other matters.*16 We shall turn to these ourselves in a moment, but first we must make a slight (but relevant!) detour to Cleveland, Ohio, and an institution then known as the Case School of Applied Science. There, in the 1880s, a physicist of early middle years named Albert Michelson, assisted by his friend the chemist Edward Morley, embarked on a series of experiments that produced curious and disturbing results that would have great ramifications for much of what followed. What Michelson and Morley did, without actually intending to, was undermine a longstanding belief in something called the luminiferous ether, a stable, invisible, weightless, frictionless, and unfortunately wholly imaginary medium that was thought to permeate the universe.

Thomson was insisting: “The ether is not a fantastic creation of the speculative philosopher; it is as essential to us as the air we breathe”—this more than four years after it was pretty incontestably established that it didn't 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–Polish border to a family of poor Jewish merchants, he came to the United States with his family as an infant and grew up in a mining camp in California's gold rush country, where his father 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 beside President Ulysses S.

At a single high school track meet in 1906, he won the pole vault, shot put, discus, hammer throw, standing high jump, and running high jump, and was on the winning mile-relay team—that is seven first places in one meet—and came in third in the broad jump. In the same year, he set a state record for the high jump in Illinois. As a scholar he was equally proficient, and had no trouble gaining admission to study physics and astronomy at the University of Chicago (where, coincidentally, the head of the department was now Albert Michelson). There he was selected to be one of the first Rhodes scholars at Oxford. Three years of English life evidently turned his head, for he returned to Wheaton in 1913 wearing an Inverness cape, smoking a pipe, and talking with a peculiarly orotund accent—not quite British but not quite not—that would remain with him for life. Though he later claimed to have passed most of the second decade of the century practicing law in Kentucky, in fact he worked as a high school teacher and basketball coach in New Albany, Indiana, before belatedly attaining his doctorate and passing briefly through the Army.


pages: 661 words: 169,298

Coming of Age in the Milky Way by Timothy Ferris


Albert Einstein, Albert Michelson, Alfred Russel Wallace, anthropic principle, Arthur Eddington, Atahualpa, Cepheid variable, Chance favours the prepared mind, Commentariolus, cosmic abundance, cosmic microwave background, cosmological constant, cosmological principle, dark matter, delayed gratification, Edmond Halley, Eratosthenes, Ernest Rutherford, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, Henri Poincaré, invention of writing, John Harrison: Longitude, Karl Jansky, Louis Pasteur, Magellanic Cloud, mandelbrot fractal, Menlo Park, music of the spheres, planetary scale, retrograde motion, Search for Extraterrestrial Intelligence, Searching for Interstellar Communications, Solar eclipse in 1919, Stephen Hawking, Thomas Kuhn: the structure of scientific revolutions, Thomas Malthus, Wilhelm Olbers

Time: 1877 Noteworthy Events: David Gill measures parallax of Mars during its opposition, deduces distance to the sun of ninety-three million miles. Time: 1879 Noteworthy Events: Albert Michelson, employing Foucault’s principle, determines velocity of light. Time: 1883 Noteworthy Events: Henry Rowland’s diffraction grating greatly improves the resolution of spectrographs. Time: 1884 Noteworthy Events: Johann Balmer determines harmonic sequence of hydrogen lines, initiating line of inquiry that will lead to investigation of the electron shells of atoms. Time: 1887 Noteworthy Events: Albert Michelson and Edward Morley perform the final and most precise in a series of experiments showing that space cannot be filled with the aether that had been thought to be responsible for transmitting light.

.* To measure this “aether drift”—as it was called, though what was thought to be drifting was not the aether but the earth—would of course be a delicate matter, since the velocity of the earth amounts to but a tiny fraction of the velocity of light. But by the latter part of the nineteenth century, technology had advanced to a sufficient degree of precision to make the task feasible. The critical experiment was conducted in the 1880s by the physicist Albert Michelson (who devoted his career to the study of light, he said, “because it’s so much fun”) and the chemist Edward Morley. Aether drift theory held that if the velocity of light was constant relative to a stationary, all-pervading aether, then when the earth in its orbit was moving away from star A and toward star B, the observed speed of the light coming from star ? would be higher than that of the light coming from star A.


pages: 695 words: 219,110

The Fabric of the Cosmos by Brian Greene


airport security, Albert Einstein, Albert Michelson, Arthur Eddington, Brownian motion, clockwork universe, conceptual framework, cosmic microwave background, cosmological constant, dark matter, dematerialisation, Hans Lippershey, Henri Poincaré, invisible hand, Stephen Hawking, urban renewal

By the late 1800s, it was evident that the universe’s secrets were proving no match for the power of human intellectual might. Indeed, with the successful incorporation of electricity and magnetism, there was a growing sense that theoretical physics would soon be complete. Physics, some suggested, was rapidly becoming a finished subject and its laws would shortly be chiseled in stone. In 1894, the renowned experimental physicist Albert Michelson remarked that “most of the grand underlying principles have been firmly established” and he quoted an “eminent scientist”—most believe it was the British physicist Lord Kelvin—as saying that all that remained were details of determining some numbers to a greater number of decimal places.1 In 1900, Kelvin himself did note that “two clouds” were hovering on the horizon, one to do with properties of light’s motion and the other with aspects of the radiation objects emit when heated,2 but there was a general feeling that these were mere details, which, no doubt, would soon be addressed.

For example, if you swim through water toward an oncoming water wave, the wave approaches you more quickly; if you swim away from the wave, it approaches you more slowly. Similarly, if you move through the supposed aether toward or away from an oncoming light wave, the light wave’s approach should, by the same reasoning, be faster or slower than 670 million miles per hour. In 1887, however, when Albert Michelson and Edward Morley measured the speed of light, time and time again they found exactly the same speed of 670 million miles per hour regardless of their motion or that of the light’s source. All sorts of clever arguments were devised to explain these results. Maybe, some suggested, the experimenters were unwittingly dragging the aether along with them as they moved. Maybe, a few ventured, the equipment was being warped as it moved through the aether, corrupting the measurements.

Imagine that we live on a three-brane that surrounds a region with four space dimensions (much as the two-dimensional skin of an apple surrounds the apple’s three-dimensional interior). The holographic principle in this setting would say that our three-dimensional perceptions would be the shadows of four-dimensional physics taking place in the region surrounded by our brane. Notes Chapter 1 1. Lord Kelvin was quoted by the physicist Albert Michelson during his 1894 address at the dedication of the University of Chicago’s Ryerson Laboratory (see D. Kleppner, Physics Today, November 1998). 2. Lord Kelvin, “Nineteenth Century Clouds over the Dynamical Theory of Heat and Light,” Phil. Mag. Ii—6th series, 1 (1901). 3. A. Einstein, N. Rosen, and B. Podolsky, Phys. Rev. 47, 777 (1935). 4. Sir Arthur Eddington, The Nature of the Physical World (Cambridge, Eng.: Cambridge University Press, 1928). 5.


pages: 186 words: 64,267

A Brief History of Time by Stephen Hawking


Albert Einstein, Albert Michelson, anthropic principle, Arthur Eddington, bet made by Stephen Hawking and Kip Thorne, Brownian motion, cosmic microwave background, cosmological constant, dark matter, Edmond Halley, Ernest Rutherford, Henri Poincaré, Magellanic Cloud, Stephen Hawking

Different observers, moving relative to the ether, would see light coming toward them at different speeds, but light’s speed relative to the ether would remain fixed. In particular, as the earth was moving through the ether on its orbit round the sun, the speed of light measured in the direction of the earth’s motion through the ether (when we were moving toward the source of the light) should be higher than the speed of light at right angles to that motion (when we are not moving toward the source). In 1887 Albert Michelson (who later became the first American to receive the Nobel Prize for physics) and Edward Morley carried out a very careful experiment at the Case School of Applied Science in Cleveland. They compared the speed of light in the direction of the earth’s motion with that at right angles to the earth’s motion. To their great surprise, they found they were exactly the same! Between 1887 and 1905 there were several attempts, most notably by the Dutch physicist Hendrik Lorentz, to explain the result of the Michelson-Morley experiment in terms of objects contracting and clocks slowing down when they moved through the ether.


pages: 233 words: 62,563

Zero: The Biography of a Dangerous Idea by Charles Seife


Albert Einstein, Albert Michelson, Arthur Eddington, Cepheid variable, cosmological constant, dark matter, Edmond Halley, Georg Cantor, John Conway, probability theory / Blaise Pascal / Pierre de Fermat, retrograde motion, Solar eclipse in 1919, Stephen Hawking

For instance, imagine a small boy who is throwing stones in all directions. For an observer approaching the boy, the stones seem to be going faster than for an observer who is running away; the velocity of the stones seems to depend on your direction and speed. In the same way, the speed of light should depend on whether you are running toward or running away from the lightbulb that’s shining on you. In 1887 the American physicists Albert Michelson and Edward Morley tried to measure this effect. They were baffled when they found no difference; the speed of light was the same in every direction. How could this be? Again, it was the young Einstein who had the answer in 1905. And again, very simple assumptions would have enormous consequences. The first assumption Einstein made seems fairly obvious. Einstein stated that if a number of people watch the same phenomenon—say, the flight of a raven toward a tree, the laws of physics are the same for each observer.


pages: 279 words: 75,527

Collider by Paul Halpern


Albert Einstein, Albert Michelson, anthropic principle, cosmic microwave background, cosmological constant, dark matter, Ernest Rutherford, horn antenna, index card, Magellanic Cloud, pattern recognition, Ronald Reagan, Solar eclipse in 1919, statistical model, Stephen Hawking

This raises the natural question, What is the medium for light? Could light travel through absolute vacuum? Many nineteenth-century physicists believed in a dilute substance, called ether, filling all of space and serving as the conduit for luminous vibrations. One prediction of that hypothesis is that light’s measured speed should vary with the direction of the ether wind. A famous 1887 experiment by American researchers Albert Michelson and Edward Morley disproved the ether hypothesis by showing that the speed of light is the same in all directions. Still, given the compelling analogy to material waves, it was hard for the scientific community to accept that light is able to move through sheer emptiness. The constancy of the speed of light in a vacuum raised another critical question. In a scenario pondered by the young Albert Einstein, what would happen if someone managed to chase and catch up with a light wave?


pages: 257 words: 66,480

Strange New Worlds: The Search for Alien Planets and Life Beyond Our Solar System by Ray Jayawardhana


Albert Einstein, Albert Michelson, Arthur Eddington, cosmic abundance, dark matter, Edmond Halley, invention of the telescope, Kuiper Belt, Louis Pasteur, planetary scale, Pluto: dwarf planet, Search for Extraterrestrial Intelligence, Solar eclipse in 1919

Because the wavelength of visible light is much shorter than the dimensions of most everyday objects—about 100 wavelengths ft across a dust speck—we rarely notice these subtle effects. When you see an array of shimmering rainbow colors on a puddle in the street, you’re seeing the result of interference, the cancellation of light waves on a thin flm of oil on the water’s surface. Even though optical interferometry is only now coming of age, its origins date back nearly a century to the efforts of Albert Michelson. Best known for measuring the speed of light, he won a Nobel Prize in Physics in 1907. Michelson knew that the angular resolution of a telescope—its ability to distinguish two stars that appear very close to each other—depended only on the size of the primary lens or mirror. If we double the size, we double the resolution. He realized that he could achieve the same effect by combining light from two smaller mirrors, without having to build a larger mirror.


pages: 634 words: 185,116

From eternity to here: the quest for the ultimate theory of time by Sean M. Carroll


Albert Einstein, Albert Michelson, anthropic principle, Arthur Eddington, Brownian motion, cellular automata, Claude Shannon: information theory, cosmic microwave background, cosmological constant, cosmological principle, dark matter, dematerialisation,, Harlow Shapley and Heber Curtis, Henri Poincaré, John von Neumann, lone genius, New Journalism,, Richard Stallman, Schrödinger's Cat, Slavoj Žižek, Stephen Hawking, stochastic process, the scientific method, wikimedia commons

You might guess that the light had been given some sort of push by dint of the fact that it was created within your moving ship. To check that, we’ll allow you to remove the curtains from the windows and let some light come in from the outside world. When you measure the velocity of the light that was emitted by some outside source, once again you find that it doesn’t depend on the velocity of your own spaceship. A real-world version of this experiment was performed in 1887 by Albert Michelson and Edward Morley. They didn’t have a spaceship with a powerful rocket, so they used the next best thing: the motion of the Earth around the Sun. The Earth’s orbital velocity is about 30 kilometers per second, so in the winter it has a net velocity of about 60 kilometers per second different from its velocity in the summer, when it’s moving in the other direction. That’s not much compared to the speed of light, which is about 300,000 kilometers per second, but Michelson designed an ingenious device known as an “interferometer” that was extremely sensitive to small changes in velocities along different directions.

See closed timelike curves Lorentz, Hendrik Antoon Lorentz transformations Loschmidt, Josef Loschmidt’s reversibility objection Lucretius lumpiness of the early universe MacDowell, Andie macrostates and arrow of time and coarse-graining counting and entropy and gas distribution and memory and mixing and possibilism and Principle of Indifference and statistical mechanics and wave functions magnetic fields magnetic monopoles Maldacena, Juan Maldacena correspondence many-worlds interpretation maps March, Hilde Marx, Karl mass and black holes and general relativity of matter and particle decay Planck mass and special relativity of the universe Mather, John matter Maxwell, James Clerk and atomic theory and classical mechanics death and electromagnetism and entropy and kinetic theory and Maxwell’s Demon and recurrence theorem and relativity and the Second Law of Thermodynamics and time asymmetry Maxwell’s Demon McTaggart, J. M. E. measurement. See also observation Méchanique Céleste (Laplace) medium, time as memory and cause and effect and cognitive instability and life and Maxwell’s Demon and physicality of information and possibilism and remembering the future mesons Messier, Charles Michell, John Michelson, Albert Michelson-Morley experiment microstates and arrow of time and black holes and closed timelike curves and coarse-graining counting and directionality of time and empty space and entropy and evolution of space of states and inflationary cosmology and memory and mixing and possibilism and Principle of Indifference and statistical mechanics and string theory and time asymmetry microwave background radiation.


pages: 551 words: 174,280

The Beginning of Infinity: Explanations That Transform the World by David Deutsch


agricultural Revolution, Albert Michelson, anthropic principle, artificial general intelligence, conceptual framework, cosmological principle, dark matter, David Attenborough, discovery of DNA, Douglas Hofstadter, Eratosthenes, Ernest Rutherford, first-past-the-post, Georg Cantor, Gödel, Escher, Bach, illegal immigration, invention of movable type, Islamic Golden Age, Jacquard loom, Jacquard loom, John Conway, John von Neumann, Joseph-Marie Jacquard, Loebner Prize, Louis Pasteur, pattern recognition, Search for Extraterrestrial Intelligence, Stephen Hawking, supervolcano, technological singularity, The Coming Technological Singularity, the scientific method, Thomas Malthus, Thorstein Veblen, Turing test, Vernor Vinge, Whole Earth Review, William of Occam

Following Popper, I shall use the term prediction for conclusions about future events that follow from good explanations, and prophecy for anything that purports to know what is not yet knowable. Trying to know the unknowable leads inexorably to error and self-deception. Among other things, it creates a bias towards pessimism. For example, in 1894 the physicist Albert Michelson made the following prophecy about the future of physics: The more important fundamental laws and facts of physical science have all been discovered, and these are now so firmly established that the possibility of their ever being supplanted in consequence of new discoveries is exceedingly remote…Our future discoveries must be looked for in the sixth place of decimals. Albert Michelson, address at the opening of the Ryerson Physical Laboratory, University of Chicago, 1894 What exactly was Michelson doing when he judged that there was only an ‘exceedingly remote’ chance that the foundations of physics as he knew them would ever be superseded?


pages: 372 words: 101,174

How to Create a Mind: The Secret of Human Thought Revealed by Ray Kurzweil


Alan Turing: On Computable Numbers, with an Application to the Entscheidungsproblem, Albert Einstein, Albert Michelson, anesthesia awareness, anthropic principle, brain emulation, cellular automata, Claude Shannon: information theory, cloud computing, computer age, Dean Kamen, discovery of DNA,, epigenetics, George Gilder, Google Earth, iterative process, Jacquard loom, Jacquard loom, John von Neumann, Law of Accelerating Returns, linear programming, Loebner Prize, mandelbrot fractal, optical character recognition, pattern recognition, Peter Thiel, Ralph Waldo Emerson, random walk, Ray Kurzweil, reversible computing, self-driving car, speech recognition, Steven Pinker, strong AI, the scientific method, Turing complete, Turing machine, Turing test, Watson beat the top human players on Jeopardy!, X Prize

This young boy was aware of English mathematician Thomas Young’s (1773–1829) experiment in 1803 that established that light is composed of waves. The conclusion at that time was that light waves must be traveling through some sort of medium; after all, ocean waves traveled through water and sound waves traveled through air and other materials. Scientists called the medium through which light waves travel the “ether.” The boy was also aware of the 1887 experiment by American scientists Albert Michelson (1852–1931) and Edward Morley (1838–1923) that attempted to confirm the existence of the ether. That experiment was based on the analogy of traveling in a rowboat up- and downstream in a river. If you are paddling at a fixed speed, then your speed as measured from the shore will be faster if you are paddling with the stream as opposed to going against it. Michelson and Morley assumed that light would travel through the ether at a constant speed (that is, at the speed of light).


pages: 282 words: 89,436

Einstein's Dice and Schrödinger's Cat: How Two Great Minds Battled Quantum Randomness to Create a Unified Theory of Physics by Paul Halpern


Albert Einstein, Albert Michelson, Arthur Eddington, Brownian motion, clockwork universe, cosmological constant, dark matter, Ernest Rutherford, Fellow of the Royal Society, John von Neumann, lone genius, New Journalism, Schrödinger's Cat, Solar eclipse in 1919, The Present Situation in Quantum Mechanics

The idea that the speed of light in a vacuum was constant—or even that light could travel through pure emptiness—was not widely accepted at the time Einstein was pondering this question. Many physicists of the day believed that light moved through an invisible substance called the “luminiferous aether,” or just “aether” for short. Earth’s motion relative to the aether should thereby be detectable. However, a well-known experiment in 1887 by American physicists Albert Michelson and Edward Morley had failed to detect such an effect. To try to reconcile light’s behavior with Newton’s laws of mechanics, Irish physicist Edward FitzGerald and, independently, Dutch physicist Henrik Lorentz suggested that fast-moving objects compress along their directions of motion. Such a shortening, called the Lorentz-FitzGerald 27 Einstein’s Dice and Schrödinger’s Cat contraction, would squash the instruments of the Michelson-Morley experiment in such a way to make it appear that the speed of light was always constant.


pages: 287 words: 87,204

Erwin Schrodinger and the Quantum Revolution by John Gribbin


Albert Einstein, Albert Michelson, All science is either physics or stamp collecting, Arthur Eddington, British Empire, Brownian motion, Drosophila, Edmond Halley, Ernest Rutherford, Fellow of the Royal Society, Henri Poincaré, John von Neumann, Schrödinger's Cat, Solar eclipse in 1919, The Present Situation in Quantum Mechanics, the scientific method, trade route, upwardly mobile

While this was going on, Schrödinger became involved in a controversy that could have had serious repercussions, and cast a permanent slight pall over his reputation. Einstein’s special theory of relativity is based upon the postulate that the measured speed of light is the same for all observers, no matter where they are or how they are moving, and this is borne out by a variety of experiments. The key practical evidence, as of the 1920s, came from a series of experiments carried out by Albert Michelson (1852–1931) and Edward Morley (1838–1923), dating back to the 1880s. In 1921, a similar experiment was carried out at the top of Mount Wilson, the site of an astronomical observatory in California, and seemed to show a slightly different result from measurements made at sea level. It was this claim that prompted Einstein to express his disbelief by making his famous comment “The Good Lord is subtle, but he is not malicious.”


pages: 412 words: 122,952

Day We Found the Universe by Marcia Bartusiak


Albert Einstein, Albert Michelson, Arthur Eddington, California gold rush, Cepheid variable, Copley Medal, cosmic microwave background, cosmological constant, Edmond Halley, Edward Charles Pickering, Fellow of the Royal Society, fudge factor, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, horn antenna, invention of the telescope, Louis Pasteur, Magellanic Cloud, Occam's razor, Pluto: dwarf planet, Solar eclipse in 1919, William of Occam

Hubble compromised by taking science classes—mathematics, astronomy, physics, chemistry, geology—as well as the prerequisite courses in the classics, including heavy doses of Greek and Latin, that would prepare him for a legal career. In regard to learning science, the timing for Hubble was perfect. Though a relatively new institution, the University of Chicago had already attracted two top physicists, Albert Michelson and Robert Millikan, who would go on to receive Nobel Prizes for their seminal work. And the Yerkes Observatory, affiliated with the university, offered one of the best telescopes then in existence. The early 1900s was a time, Hubble later recalled, when the world was astir: “Motor cars, at last, were successfully competing with horses. Airplanes were trying their wings. Bleriot had just flown the English channel, and…the wireless was groping its way over the map.


pages: 782 words: 245,875

The Power Makers by Maury Klein


Albert Einstein, Albert Michelson, Augustin-Louis Cauchy, British Empire, invention of radio, invention of the telegraph, James Watt: steam engine, Louis Pasteur, luminiferous ether, margin call, Menlo Park, price stability, railway mania, the scientific method, trade route, transcontinental railway, working poor

Sound waves moved through air, ocean waves through water; the lumiferous ether became the substance through which light waves moved. As such it was considered to be motionless, a constant through which all other bodies, including the earth as it orbited the sun, traveled. Light also traveled through the ether, which explained why distant stars were visible.70 However, this notion of the ether received an unexpected and fatal blow from, of all things, a failed experiment by physicist Albert Michelson. He first became absorbed in the task of measuring accurately the speed of light. Little progress had been made since the work of Danish astronomer Olaus Roemer in 1676, but Michelson managed in 1879 to come up with the figure of 186,320 miles a second, remarkably close to the 186,282 miles later accepted. Two years later, with financial backing from Alexander Graham Bell, he invented an interferometer, which could split a light beam in two, send the parts along separate paths, and bring them back together again.