Do Black Holes Emit Different Particles at Varying Intensities?

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Discussion Overview

The discussion revolves around the nature of Hawking radiation emitted by black holes, specifically focusing on the types of particles emitted, such as photons, gravitons, and neutrinos, as well as the implications of mass and charge in this context. Participants explore theoretical aspects, including the potential for black holes to emit gluons and the conditions under which neutrino-antineutrino pairs might be produced.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that both photons and gravitons can be Hawking radiated by a massive black hole, questioning whether their emission intensities are equal or differ due to the properties of their respective fields.
  • There is a query about the conditions under which a black hole can emit neutrino-antineutrino pairs, including whether these pairs are emitted at a flavor or mass eigenstate.
  • Another participant proposes that if the lower mass eigenstate of neutrinos is either zero or very small, it could affect the power emitted as neutrino-antineutrino pairs compared to photons.
  • One participant argues that a black hole emitting a gluon would acquire a color charge, which they claim is not permissible, although they acknowledge that hadrons could be emitted under specific conditions.
  • Another participant mentions the possibility of a massless neutrino state affecting the composition of Hawking radiation, noting that the powers of emitted particles are not equal due to differences in spin states.
  • There is a contention regarding the nature of Hawking radiation, with one participant asserting that it is not solely based on particle pairs, while another emphasizes the thermal nature of the radiation and the improbability of producing massive particles at the temperatures associated with stellar mass black holes.

Areas of Agreement / Disagreement

Participants express differing views on the types of particles that can be emitted by black holes and the implications of mass and charge in this process. There is no consensus on the conditions for neutrino emission or the role of gluons in Hawking radiation.

Contextual Notes

Participants highlight the complexities surrounding the mass of neutrinos and the thermal nature of Hawking radiation, indicating that the discussion is influenced by assumptions about particle properties and the conditions under which they are emitted.

snorkack
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A photon and a graviton are both certainly devoid of mass and charge.
Therefore a massive black hole can certainly Hawking radiate either.

Is the intensity of photon radiation and graviton radiation by a black hole exactly equal, or different at some specific proportion due to different properties of electromagnetic and gravitational fields?

When can a black hole Hawking radiate a neutrino-antineutrino pair?
Are neutrino-antineutrino pairs Hawking radiated at a flavour eigenstate (at some average mass), or at a mass eigenstate?
There are observed square of mass differences with the two higher eigenstates. But is there a nonzero lower bound to the lower mass eigenstate of neutrino?

If the lower mass eigenstate of neutrino has mass which is zero or nonzero but small compared to the mass of photons and gravitons emitted by black hole, what would be the power emitted as neutrino-antineutrino pairs compared to the power emitted as photons?

And can a black hole have colour?
Black hole has no hair. Only mass, angular momentum and electric charge.
Colour is not a listed legal hair of a black hole.

A gluon is supposed to have no mass. Even a small gluon mass would be supposed to disturb some observed symmetries (which?).

If a gluon has no mass and a black hole no colour, what can stop a black hole from Hawking radiating a gluon? Because of no hair, the black hole has no colour to colour confine the colourful gluon!
 
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A black hole emitting a gluon would get a color charge and the gluon would have a free color charge as well - it cannot do that. It can emit hadrons, but it has to be really small to have a relevant probability of that.

It is not completely impossible that one neutrino type could be massless, in that case Hawking radiation would also contain neutrinos in addition to photons and gravitons. The powers are not equal due to spin states and so on, but they are of the same order of magnitude. It would be extremely weird to have one massless neutrino state, however.
 
I was under the impression that Hawking radiation can be anything that is created in pairs? Why is mass a problem?
 
Hawking radiation has nothing to do with pairs. Don't trust the pop science myths.

The natural mass for the lightest neutrino would be around 0.01 to 1 meV, or 10 to 12 orders of magnitude above the temperature of stellar mass black holes. It can be much lighter or even massless, but that would be quite odd. The radiation is thermal, things with a mass of billions of times the temperature are not produced with any relevant probability.
 

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