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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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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The gravitational Doppler shift
An observer in a free falling elevator measures no frequency shift in an EM waves emitted at the bottom of the elevator and received some time later at its top. Not only the free falling observer, but ...
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Unruh effect on the Earth's surface [duplicate]
Physics of accelerating observers can be written in Rindler's spacetime. Minkowski observers feel vacuum with 0 temperature, whereas Rindler observers feel same vacuum with non-zero temperature but ...
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Validity of Einsteins Principle Of Equivalency [duplicate]
My question is
Does the equivalency principle still hold up when considering the following?
Note: thought experiment disregarding air resistance, friction etc...
Situation 1. two objects are in ...
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The Equivalence Principle
Here is how I understand the equivalence principle. The equivalence principle states that, LOCALLY, the spacetime looks Minkowskian. Therefore, since gravity is locally uniform, then the metric ...
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Question about observing in a non-inertial frame of reference
I was going through this answer which beautifully explains why free falling objects are in an inertial frame of reference. This is the example that was given to explain why observers in a non-inertial ...
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What is the relationship between an object's surroundings and it being in free-fall?
I understand the general concept of an object being in free-fall, but I am still confused on some aspects.
What is the relationship between an object's surroundings and its being in free-fall? I ...
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Can you directly feel the effect of gravity, or only opposing forces?
I was trying to think through the consequences of Einstein's observation that a freely falling body does not experience its own weight. And, as freely falling (or "inertial") bodies will ...
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Inertial Frames, Relativity, Equivalence Principle and the Twin Paradox [duplicate]
I am very unsatisfied with how people resolve the twin paradox. As a little background, here is what the Wikipedia article about the paradox states...
In physics, the twin paradox is a thought ...
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Is there any intuitive way to understand the Strong and Weak Equivalence Principle?
The WEP talks about the indistinguishability of motion in a constant gravitational field and an inertial force in an accelerating reference frame. The SEP further claims that this indistinguishability ...
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Laser beam in a lift thought experiment in general relativity
I am reading "Cosmology - A very short Introduction" by P. Coles (2001) and I am a bit confused with a particular part of the text in p.24 about the famous thought experiment involving a ...
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