The equivalence-principle tag has no wiki summary.
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4answers
658 views
Is there a fundamental reason why gravitational mass is the same as inertial mass?
The principle of equivalence - that, locally, you can't distinguish between a uniform gravitational field and a noninertial frame accelerating in the sense opposite to the gravitational field - is ...
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9answers
2k views
How does this thought experiment not rule out black holes?
How does the following brief thought experiment fail to show that general relativity (GR) has a major problem in regards to black holes?
The full thought experiment is in my blog post. The post ...
1
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1answer
299 views
How does Newton's 2nd law correspond to GR in the weak field limit?
I can only perform the demonstration from the much simpler $E = mc^2$.
Take as given the Einstein field equation:
$G_{\mu\nu} = 8 \pi \, T_{\mu\nu}$
... can it be proved that Newton's formulation ...
4
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3answers
1k views
Why is the equivalence principle so important to general relativity?
In its simplest form, equivalence principle states that the inertial mass and the gravitational mass should be the same. This is easy to understand.
But why is it so important to the formulation of ...
3
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5answers
492 views
How are the comoving coordinates NOT a prefered reference frame?
Physics me this:
The equivalence principle has rigorous physical definitions that say, for one, that the laws of physics are the same in all inertial reference frames. This is to say that the ...
2
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3answers
184 views
Why can't we think of free fall as upside down rocket?
/\
/ \
| |
| m |
| |
------ <--- floor (Rocket A)
This rocket is accelerated (g) upwards then mass(m) falls on the floor.
...
10
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7answers
2k views
Would it help if you jump inside a free falling elevator?
Imagine you're trapped inside a free falling elevator. Would you decrease your impact impulse by jumping during the fall? When?
5
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2answers
1k views
Does the equivalence between inertial and gravitational mass imply anything about the Higgs mechanism?
For example: the role it might play in a theory of quantum gravity (ie causing space-time curvature)?
I realize that inertial mass can result from binding energy alone. Has the equivalence principle ...
1
vote
1answer
140 views
Accelerating elevator?
If your in an elevator accelerating downwards faster than gravity, would you be pushed up to the ceiling? Since gravity cannot match the acceleration of the elevator, you're wouldn't be able to move ...
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4answers
1k views
Water pressure in free fall
The increasing water pressure as you go deeper is generally explained in terms of the weight of the water column above the observation point pressing down. The question, then, is what would happen if ...
6
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8answers
451 views
Gravity theories with the equivalence principle but different from GR
Einstein's general relativity assumes the equivalence of acceleration and gravitation. Is there a general class of gravity theories that have this property but disagree with general relativity? Will ...
4
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2answers
194 views
How (or why) equivalence principle led to Einstein field equations?
If equivalence principle was origin of general relativity what was the process that this principle led Einstein to developed his theory of general relativity?
4
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1answer
141 views
Weak equivalence principle tests
on the wikipedia article about the equivalence principle there is a mention about testing the EP against parity-violating masses;
"The equivalence principle is untested
against opposite ...
3
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3answers
191 views
Does the equivalence principle mean that the Earth is expanding?
Popular books suggest that for an observer in the Einstein lift the following situations are equivalent:
1, the lift hangs motionless (relative to the Earth) on a cable in the gravitational field of ...
1
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0answers
104 views
Use of Principle of Equivalence
Let $x^\mu$ be the coordinates of a reference frame, $K$, where all bodies feel the same constant and uniform acceleration $\textbf{a}=\textbf{g}=-\nabla\varphi$; let $\xi^\mu$ be the coordinates of a ...
