All Questions
Tagged with unruh-effect event-horizon
10
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Don't all objects that collapse have an apparent event horizon and so Hawking radiates?
So say there is an object that is in the form of gas and dust and a core that weighs 10 earths is in the center and there is a sphere of gas around it that weighs 50 Earths, so the final mass is only ...
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Cosmological horizon and Hawking/Unruh radiation? [closed]
I have two questions about cosmological horizons and their emission of radiation
The first one is:
There are some authors that propose that dark energy or the accelerated expansion of the universe ...
- 2,462
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Might the tiny Hawking radiation from our cosmic event horizon (CEH) be additive, since my CEH is not your CEH?
Concerning our cosmic event horizon, an interesting question arises from the seemingly innocent statement, "My cosmic event horizon is not your cosmic event horizon." Ie: Since 'you' and 'I'...
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Do the null geodesics of photons emitted by Hawking radiation arise from the event horizon?
It is a well-known explanation of Hawking radiation that it originates from the quantum fluctuations near the horizon. Does it mean that one can look at the photons (part of the radiation) and follow ...
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Firewall in Rindler horizon
In arXiv:1409.1231 in section 3.5 above equation (3.34) Daniel Harlow says
More precisely if the left and right wedges are completely uncorrelated, as in
the state 3.33, then the typical difference ...
- 1,580
4
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5
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Flux and radiation pressure from Unruh radiation?
A collection of accepted answers on Physics Exchange paint a seemingly inconsistent picture of Unruh radiation and it's isotropy. One of the most sophisticated answers, from Lubosz Motl, to the ...
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Direction of Unruh radiation
In case of a black hole, the direction of the Hawking radiation is from the horizon to the observer. The corresponding effect in the Rindler spacetime is the Unruh radiation.
Intuitively, a rapidly ...
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On the necessity of an event horizon for the Hawking-Unruh effect
I first explain my reasoning. I know that a Schwarzschild metric is the right metric outside any spherical object, but I also know that it is correct in the empty space. So I thought: why we don't ...
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If I spin around why do the stars not dissappear?
Galaxies at the far limit of the visible universe are moving away from us near the speed of light. There may be some beyond that that are moving away from us faster, so the universe appears to have an ...
- 942
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Horizon and Unruh radiation for a finite period of acceleration
It's a well known fact that an observer that accelerates at a constant rate from $-c$ at past infinity to $+c$ at future infinity sees a horizon in flat Minkowski spacetime. This is easy to see from a ...
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