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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Will gravitational waves decay into photons? (and by how much?)
We know intense regions of curvature, for example near a black hole horizon, induce a flow of electromagnetic waves (and, less so, other particles). aka Hawking radiation.
By contrast, curvature in ...
user84158
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Boulware and Unruh vacuum in Schwarzschild spacetime
I am studying quantization in Schwarzschild spacetime. In class the Boulware vacuum $\left| B \right>$ has been defined using the o.n. modes $u_I(x) = \frac{1}{4\pi \sqrt{\omega}}e^{-i\omega v}$, $...
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Does accelerating blackhole grow in size due to constant infalling unruh radiation?
Unruh effects stipulates that an accelerating observer will observe a thermal bath, like blackbody radiation, whereas an inertial observer would observe none. Now assume a constantly accelerating ...
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Path Integral for Unruh Effect
In derivation of Unruh effect, according to arxiv 2108.09188, we have
$$
\langle\phi_L|\exp(-\pi H)|\phi_R\rangle=\int_{\phi=\phi_R}^{\phi=\phi_L} D\phi e^{-S_E}\propto \int_{lower\space half\space ...
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How does Unruh detector work?
It is often said that an inertial observer in flat spacetime vacuum will see an accelerating observer thermalize (Unruh Effect). If an accelerated observer takes a particle in a box coupled with the ...
user310742
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Is it possible to explain radiation of an accelerated charged particle via the Unruh effect?
From the point view of a noninertial observer, if a charged particle accelerates then it can catch the Unruh particle and excite. After that, the charged particle emits it and falls back to its ground ...
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Role of horizon in Unruh effect
I’m reading this on the Unruh effect and it is derived by calculating the Bogoliubov coefficients between the Minkowski and Rindler observer. Rindler observers use a different set of modes to describe ...
user310742
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Why is the Unruh effect observer dependent?
Why Unruh radition is observer dependent why Hawking radition is not observer dependent?
I know hawking radiation is caused by the creation of a pair partice and antiparticle in two different sides ...
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Bogoliubov coefficients between inertial frames
The Klein–Gordon Equation in Minkowski space says $\partial_\mu \partial^\mu \phi+ m^2 \phi = 0$.
The solution has modes $e^{ikx}$, $e^{-ikx}$ scaled by creation and annihilation operators $a^{\dagger}...
user310742
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How is Hawking radiation formally derived?
[EDITED] I'm a postdoc working in cond-mat/quant theory, and I've heard some explanations of Hawking radiation that strike me as inconsistent or silly (e.g., in terms of pair production). I'm hoping ...
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Does String Theory predict things like Unruh effect and Hawking radiation?
I've seen the other post about this, but the answer only discusses Unruh effect rather than String theory.
Hawking radiation and Unruh effect solidify fields as the universe's fundamental objects. ...
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Does the Unruh effect assume its conclusion?
Unruh effect says that accelerating observers see the single particle states of inertial frames as thermal baths.
But it proves it by defining the particle states in the accelerating observer's frame ...
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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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Informal derivation of the Unruh temperature
Imagine a charged particle of mass $m$ at rest in the electromagnetic vacuum.
The particle interacts most strongly with zero-point modes that have a wavelength $\lambda_C$ similar to the Compton ...
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Unruh effect origin of particle
I have a little confusion about where from the particle are coming in Unruh effect. Vacuum fluctuation is always there and does not depend on whether the frame/detector is moving or not. Vacuum ...
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