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1

BHs can carry charge - so you squirt some electrons into it to charge it and then use an electrical charge on the parabolic reflector to couple it to the ship.


2

It is not a coincidence. It has to work like that. The deficit angle has to be zero. It's most convenient to see it in the Feynman's path integral approach to quantum mechanics. One works in the Euclideanized spacetime to calculate the temperature $T=1/\beta$ partition sum. Let us consider the full finite-size black hole; the Rindler geometry is a local ...


11

To answer this we need to talk a bit about how particles are described in quantum field theory. For every type of particle there is an associated quantum field. So for the electron there is an electron field, for the photon there is a photon field, and so on. These quantum fields occupy all of spacetime i.e. they exist everywhere in space and everywhere in ...


6

@JohnDuffield: I can give you both a correct answer in simple terms and the fairy tale, together with references to an explanation how the fairy tale is related to the real thing! The dry facts are that two real particles (e.g., two photons, or an electron and a positron) are created from the energy in the very strong gravitational field near the horizon of ...


1

Suppose you have two systems $S_1,S_2$ with Hilbert spaces $H_1,H_2$ with a density matrix $\rho$ on $H_1\otimes H_2$. The partial trace of $\rho$ over the Hilbert space of one of the systems, $H_1$ say gives you a reduced density matrix $\rho_2$. The reduced density matrix predicts the expectation values of all the measurements you can conduct on $S_2$ ...


-2

Since everybody seems to need the kid who cries that the emperor has no clothes, I am more than happy to make the same statement in an answer: the question posed by the black hole complementarity paradox is unphysical. Information is always lost in any physical systems. Thermodynamics is about nothing else than information loss. Whether it's melting ice ...


2

So, black holes should emit not only photons, but also gravitons, axions (if they exist), and also more massive particles like electrons, protons, and even smaller black holes (with extremely small probability). There exists a misunderstanding here, I think. Black body radiation is connected with electromagnetic radiation, and has been derived and ...


-3

Is this analogy of Hawking Radiation correct? No. I know you read stuff like this on the internet, in pop-science articles, and even in textbooks. But it's not correct at all. Sorry. I'll go through it step by step: Within the ergosphere of the black hole, virtual pairs of particles and anti-particles are constantly appearing No they aren't. ...


3

As the comments have suggested, the problem is that your description of virtual particles appearing to vacuum fluctuations is wrong. Have a look at my answer to Black holes and positive/negative-energy particles for more on this. There isn't an explanation of what is really going on that is accessible to the non-quantum field theory nerd (though I have ...


1

To understand the origin of black body radiation, which is what every material body with a temperature T has been measured to emit, one has to go to quantum statistical mechanics. Atoms and molecules, to start with, in any ensemble, interact with the electromagnetic radiation. At that level, the processes are quantum mechanical. In quantum mechanics the ...


0

Suppose you crossed the event horizon. But you will never make up to the singularity. What happens at the singularity is still unanswered. Hawking's radiation is solely explained based on thermodynamic basis. Hawking assumed the blackhole as a black body. It could absorb any wavelength radiation. So at a low temperature the black body should emit radiations. ...



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