Questions tagged [unruh-effect]
This tag is for questions regarding to the Unruh effect (also known as the Fulling–Davies–Unruh effect), the hypothetical prediction that an accelerating observer will observe a thermal bath, like blackbody radiation, whereas an inertial observer would observe none. It was described by Stephen Fulling in 1973, Paul Davies in 1975, and William Unruh in 1976.
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Static Patch Decomposition of Bunch Davies Vacuum
In the Jerusalem Lectures on Black Holes section 3.3 the author considers a QFT in Minkowski space. He then picks out a space coordiante, say $x$, and divides the Hilbert space $H$ of the QFT in two ...
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Is there an analogous Unruh effect for observers on a rigidly rotating ring?
I read up on the Unruh effect recently and what I got from it is that its basically a result of transforming to Rindler coordinates and using a Bogoliubov transformation to change the creation and ...
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GZK Limit in the Far Future and interaction with Vacuum energy?
The GZK limit stops high energy protons from propagating long distances because of the interaction with the CMB. But as the universe ages the CMB will become more red shifted. Will this mean the the ...
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What if acceleration changes in the Unruh effect?
Based on the Unruh effect, when a observer accelerates then he will see a thermal bath. mathematically the vacuum state for a non-inertial observer is
$$|0\rangle=\text{cos}^{-1}(r)\sum_{n=0}^{\infty}\...
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How to relate the two expressions of thermal spectrum?
I am reading a proof of the fact that if there exists a monochromatic plane electromagnetic wave for an observer in frame $S$, an observer in a frame $S'$, which is uniformly accelerated with respect ...
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Accelerating frame of reference, fermions and probability conservation
I'm looking at solutions to the massless Dirac equation in an accelerating frame of reference in $(1+1)$-dimensions but the wave functions I get appear to violate probability conservation.
My ...
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Unruh Radiation from hovering?
I know that masses on their own don't produce Unruh radiation outside of black holes which produce a similar effect known as Hawking radiation. However, what if some observer hovers above the Earth ...
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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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Behavior of Rindler modes for massless scalar field in 3+1 dimensions
Thank you in advance for any answer to my question.
I'm having trouble understanding the behaviour of the mode functions of a massless Klein-Gordon field in Rindler coordinates. We are in 3+1 ...
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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 ...
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Why is Unruh radiation in a full 4$\pi$ solid angle contrary to Hawking's radiation?
I have some trouble asking this question, so I will try a roundabout approach to explain what I mean.
If (outside of Earth atmosphere) one looks at the sun from different distances, the light coming ...
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Can we infer Hawking radiation assuming the Unruh effect?
An observer near the event horizon of a black hole will experience an extremely strong gravitational field.
Due to the principle of equivalence, this observer cannot locally distinguish between this ...
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Are non-virtual particles of QFT real?
Perhaps the question may seem a bit provocative, but it refers to several mathematical and, presently physical facts, pointed out a long time ago:
The Unruh effect suggests that an accelerated ...
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What are the experimental difficulties in measuring the Unruh effect?
The Unruh effect was predicted in 1976.
As someone with no background in experimental physics I find it surprising this effect hasn't been measured yet. What are the experimental difficulties (and ...
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Fulling–Davies–Unruh effect with non-uniform acceleration
Can there be some version of the Fulling–Davies–Unruh effect, in which the accelerating observer is moving with a non-uniform acceleration? Can someone refer some papers to read?
If there can not be ...
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