SWaB: could black holes be dark matter?

[notFritzArgelander]

https://www.forbes.com/sites/startswith ... e374c129bb

[Lady Fraktor]

Will read this in the morning, looks interesting

[Lady Fraktor]

A good read but I was hoping for a new approach instead of re-doing the old discussion.

[notFritzArgelander]

A good read but I was hoping for a new approach instead of re-doing the old discussion.

Yeah.... It was disappointing. I still think that relatively low was BHs might have a role to play. Small BHs of lunar mass could still be in play.

t≈2.1∙10^67 years 〖(M/M_⨀ )〗^3

Where t is the evaporation time assuming the CMB is at absolute zero.

If we solve for an initial mass that might be evaporating now we estimate 0.85x10^(-19) for the fraction of a solar mass. This is why 10^11 kg masses would be interesting. This is a billion time the mass of Ceres and surveys for primordial BHs are cut off at about the mass of Saturn. So.... I think there's more life in this hypothesis than Ethan does.

Maybe the next interstellar object to fly by will be a small BH? I think that the phase transitions with spontaneous symmetry breaking among the standard model forces could nucleate some fluctuations that wouldn't show up in the CMB fluctuation spectrum. They would be earlier and invisible behind the CMB wall.

I'm more interested in microlensing surveys driving the mass down.

[Lady Fraktor]

That is an interesting thought!
Have a great night I am off to work.

[notFritzArgelander]

That is an interesting thought!
Have a great night I am off to work.

You too. One more post and then... Cygnus calls.

[notFritzArgelander]

A good read but I was hoping for a new approach instead of re-doing the old discussion.

Yeah.... It was disappointing. I still think that relatively low was BHs might have a role to play. Small BHs of lunar mass could still be in play.

t≈2.1∙10^67 years 〖(M/M_⨀ )〗^3

Where t is the evaporation time assuming the CMB is at absolute zero.

If we solve for an initial mass that might be evaporating now we estimate 0.85x10^(-19) for the fraction of a solar mass. This is why 10^11 kg masses would be interesting. This is a billion time the mass of Ceres and surveys for primordial BHs are cut off at about the mass of Saturn. So.... I think there's more life in this hypothesis than Ethan does.

Maybe the next interstellar object to fly by will be a small BH? I think that the phase transitions with spontaneous symmetry breaking among the standard model forces could nucleate some fluctuations that wouldn't show up in the CMB fluctuation spectrum. They would be earlier and invisible behind the CMB wall.

I'm more interested in microlensing surveys driving the mass down.

Typo correction: t≈2.1∙10^(67) years [(M/M_⨀ )]^3 for the life of a BH against Hawking evaporation
0.85x10^(-19) for the fraction of a solar mass of a BH surviving the life of the universe translating into 10^(11) kg.

The electroweak phase transition in the Standard Model happens at energies of several 100s of Gev. That corresponds to a much smaller mass BH. More like 10^(-23) the Sun. Or in other words 10^7 kg. So the electroweak phase transition is unlikely a source of primordial BHs.