All Questions
Tagged with particle-physics general-relativity
68
questions
2
votes
2
answers
239
views
Does an observer moving in a circle with constant angular velocity in space experience GR gravitational time dilation?
Assuming that there are no other planets or other gravitational sources around the observer in empty space, would the observer's very fast circular motion create GR gravitational or else called ...
- 4,170
5
votes
1
answer
342
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Why did Dirac say that atomic time is different from relativistic time, and that gravity is becoming weaker? What is the relation between the two?
In this gem of an interview in 1982 with Friedrich Hund, Dirac says at 09:17 that there is some theoretical basis and observational evidence that atomic time and distances are different from ...
- 1,421
1
vote
1
answer
84
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What happens when a galactic body gets bigger?
In my simple non-quantum non-nuclear but enthusiasm-filled mind, I fascinate that as a galactic body become much more massive, it can reduce matter first down to its building blocks, then eventually ...
- 137
1
vote
0
answers
110
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Why is the entry barrier in Physics Research Topics so high? [closed]
Why is the entry barrier in physics research so high?? When I try to read a research paper to see the latest developments in a particular topics I am always held back by my mathematical abilities. And ...
36
votes
7
answers
4k
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Why can’t gravitons distinguish gravity and inertial acceleration?
If gravitons mediate the gravitational force, couldn’t the detection of gravitons by an observer be used to distinguish whether they are experiencing gravitational acceleration vs. inertial ...
- 481
0
votes
1
answer
78
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Moving particle with GR not taken into account vs GR taken into account
If we imagine a lightwave moving through space without considering how the space is deformed due to the energy and momentum of the light, we would find it redshifted once we take GR into account ...
- 631
1
vote
0
answers
62
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Lagrangian of free particle relativistic case
Why must the covariant Lagrangian of a free particle be a first-order differential?
5
votes
1
answer
283
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The Explosive Force of the Braking Alcubierre Drive - What would this look like? [closed]
The Alcubierre Drive and faster than light travel more generally may be locked away in the realm of fiction forever. That might be depressing to some people but I think their impossibility is really ...
- 51
1
vote
1
answer
41
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Question about relative velocity and black hole formation in a fixed target experiment
In a given frame S, consider an inelastic collision between a particle A and a fixed target B. In frame S, the relative velocity of A (and thus the kinetic energy) to an observer in frame S is not ...
- 100
0
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1
answer
113
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Is there a way to detect gravitational waves in subatomic particles?
Consider the hypothetical situation of two electrons orbiting each other with a certain radius between them, going at extremely high speeds.
Would this create gravitational waves strong enough to be ...
user250721
-1
votes
1
answer
205
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Do particles produce gravitational waves?
We have obviously detected gravitational waves at very large scales, but what about small scales? I accept the answer that they would be indetectable, however I would think it would, considering the ...
user250721
2
votes
0
answers
180
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Spin particles in curved spacetime
On the Lorentz space, particles are axiomatized as unitary projective representations of the Poincaré group (according to Wigner if I recall correctly). It is then possible to specify a (non-charged) ...
- 41
1
vote
3
answers
202
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What is the result that that differs by many orders of magnitude between QM and GR? [duplicate]
It is well known that QM and GR are deemed incompatible due to a discrepancy in some calculations which I have read can differ by large magnitudes. What are these calculations to which people are ...
- 145
-1
votes
1
answer
57
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What does the photon feel when it hits an asteroid on its path to earth [duplicate]
If a photon was approaching earth, after 1 minute(from earths reference frame) an asteroid comes on the photons path. And it hits the asteroid, but from the photons reference frame time doesn't pass ...
2
votes
0
answers
131
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Elementary particle (electron) and non-elementary (proton) spagettification
I understand that spagettification means the vertical stretching and horizontal compression of objects into long thin shapes in a non-homogenous gravitational field, it is caused by tidal forces.
Now ...
- 29k