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Wayward Satellites Test Einstein's Theory of General Relativity (scientificamerican.com)
An anonymous reader quotes a report from Scientific American: In August 2014 a rocket launched the fifth and sixth satellites of the Galileo global navigation system, the European Union's $11-billion answer to the U.S.'s GPS. But celebration turned to disappointment when it became clear that the satellites had been dropped off at the wrong cosmic "bus stops." Instead of being placed in circular orbits at stable altitudes, they were stranded in elliptical orbits useless for navigation. The mishap, however, offered a rare opportunity for a fundamental physics experiment. Two independent research teams -- one led by Pacome Delva of the Paris Observatory in France, the other by Sven Herrmann of the University of Bremen in Germany -- monitored the wayward satellites to look for holes in Einstein's general theory of relativity.
Einstein's theory predicts time will pass more slowly close to a massive object, which means that a clock on Earth's surface should tick at a more sluggish rate relative to one on a satellite in orbit. This time dilation is known as gravitational redshift. Any subtle deviation from this pattern might give physicists clues for a new theory that unifies gravity and quantum physics. Even after the Galileo satellites were nudged closer to circular orbits, they were still climbing and falling about 8,500 kilometers twice a day. Over the course of three years Delva's and Herrmann's teams watched how the resulting shifts in gravity altered the frequency of the satellites' super-accurate atomic clocks. In a previous gravitational redshift test, conducted in 1976, when the Gravity Probe-A suborbital rocket was launched into space with an atomic clock onboard, researchers observed that general relativity predicted the clock's frequency shift with an uncertainty of 1.4 x 10-4. The new studies, published last December in Physical Review Letters, again verified Einstein's prediction -- and increased that precision by a factor of 5.6. So, for now, the century-old theory still reigns.
Einstein's theory predicts time will pass more slowly close to a massive object, which means that a clock on Earth's surface should tick at a more sluggish rate relative to one on a satellite in orbit. This time dilation is known as gravitational redshift. Any subtle deviation from this pattern might give physicists clues for a new theory that unifies gravity and quantum physics. Even after the Galileo satellites were nudged closer to circular orbits, they were still climbing and falling about 8,500 kilometers twice a day. Over the course of three years Delva's and Herrmann's teams watched how the resulting shifts in gravity altered the frequency of the satellites' super-accurate atomic clocks. In a previous gravitational redshift test, conducted in 1976, when the Gravity Probe-A suborbital rocket was launched into space with an atomic clock onboard, researchers observed that general relativity predicted the clock's frequency shift with an uncertainty of 1.4 x 10-4. The new studies, published last December in Physical Review Letters, again verified Einstein's prediction -- and increased that precision by a factor of 5.6. So, for now, the century-old theory still reigns.
Think of a coordinate system with the three usual dimensions (x, y and z) and then one other dimension orthogonal to the other three, this extra dimension is time (t).
An object at rest describes a vector where x= y = z = 0 and t = c (the speed of light).
As an object moves the vector rotates to point in a new direction and therefore the resolution of the (now rotated) vector on the t dimension is smaller than when the object was at rest. Therefore as the object moves time passes more slowly for the object. When the object moves at speed c, time stops for the object.
I leave it for others to translate this model to a gravitational field (it's been too long and I've forgotten).
I said, look into it. In other words, read about it and see if it supports your opinion or contradicts it. Muons are created in particle accelerators. The ones created are moving fairly slowly compared to cosmic rays. We can measure the half life of them before they decay, which is 2.2 microseconds. The ones created by cosmic rays hitting the atmosphere are moving at a speed where the muon should go about 450m before decaying. Yet, they reach the Earth's surface from 60-100 km up where they are created in the atmosphere. The reason they last that long and can move that far is due to time dilation, since they are moving at relativistic speeds.