Questions tagged [equivalence-principle]
In general relativity, the equivalence principle is the equivalence of gravitational and inertial mass, along with the observation that the gravitational "force" experienced on a massive body is the same as the pseudo-force experienced by an observer in a non-inertial (accelerated) frame of reference.
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What do we know about mass equivalence principle for non-nucleons, mass in e.g. neutrino oscillations?
While special relativity says inertial mass is equivalent with energy, there are at least two more types of mass, for which equivalence seems not so certain - let me briefly summarize and ask for more ...
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Equivalence principle and principle of relativity
If equivalence principle was not true could we have almost inertial reference frames near the earth? Specially, is it was possible for a person in a train to know that if it is standing still or it is ...
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Principle of relativity near a charged earth
If earth was electrically charged is it was possible for a person in a train to know that if it is standing still or it is moving by constant velocity?
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The concept of Inertia and GR
How is the concept of inertia handled in GR? From what I have read that it is still handled as an intrinsic element of mass. Are there other ways to understand inertia that GR offers?
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Gravity same as free space?
Einstein’s remarkable insight was that a man falling freely experiences no gravity and his experiences are identical in some sense to a man far away in free space. But the man falling is increasing ...
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Is time dilation in gravity truly indistinguishable from acceleration?
The equivalence principle says they’re locally indistinguishable. But is there a measurable, nonlocal experiment (e.g. involving tidal forces or redshift gradients) that distinguishes between ...
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Rindler Time Dilation vs Gravitational Time Dilation in Accelerating Refernece Frame
I am trying to reconcile Rindler time dilation with gravitational time dilation between two points in an accelerating frame of reference separated by a distance d (e.g. 1 light-second). As far as I ...
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About the dynamics of an accelerated elevator
I’ve read other discussions of this problem, but I’m not fully satisfied with the answers because I want to examine the case of an elevator accelerating (up or down) with a person inside, specifically ...
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Violation of equivalence principle [closed]
Light is the fastest thing in universe but the speed of light is still a finite number. Imagine me and my friend are some separated by some distance and I fire a laser at my friend. If my friend is in ...
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Geodetic: does one entertain a force or not?
I have a basic problem on geodetic. Does a human who jumps out of of plane feel acceleration $a$ as in the equation $$a = g~?$$ I disregard the atmosphere. I think he does but also on the contrary as ...
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Why are there no reported experimental deviations from the Equivalence Principle due to nonhomogeneous gravitational fields?
Wikipedia says: [The assumption of? -ed] Uniformity of the gravitational field eliminates measurable tidal forces originating from a radial divergent gravitational field (e.g., the Earth) upon finite ...
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Sabine Hossenfelder and the meaning of acceleration
I've just watched Sabine Hossenfelder's Gravity video on YouTube. A couple of things in this have got my head spinning, but I think they basically come down to the definition of "accelerating&...
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Tidal Forces vs. Einstein’s Equivalence Principle [duplicate]
The essence of Einstein’s Equivalence Principle is that in General Relativity a free falling object’s inertial frame of reference is equivalent to the inertial frame of reference of an object floating ...
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Why do we need the metric in GR?
The equivalence principle only needs the connection coefficients to describe gravity so why isn't the metric just the Minkowski metric and we work with the connection coefficients? Is there a ...
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Do we use the equivalence principle to quantify gravitational potential energy?
Imagine a helium balloon suspending a 10kg rock just above the ground. Because neither is moving, we would normally say that they have potential energy, with the potential for the balloon to shoot ...
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