All Questions
Tagged with black-hole mass
34
questions
23
votes
3
answers
4k
views
From an outsider's perspective, how can a black hole grow if nothing ever crosses the event horizon?
Due to time dilation, an outside observer never sees a falling object actually cross the event horizon. I'm not referring to the optical illusion of red-shifted light making objects appear to fade ...
user52416
3
votes
1
answer
119
views
What mass does an evaporating black hole have when it's schwarzschild radius equals the Planck length?
I am referring to Hawking radiation and the decrease in mass of the black hole with time
user48394
3
votes
1
answer
290
views
How do you convert an uncertainty quoted in dex to a 1-sigma uncertainty?
The black hole mass measurement uncertainties from this paper https://arxiv.org/pdf/2006.15150.pdf are quoted in "dex" and are said to be equal to 0.4 dex. I have seen from certain papers ...
- 33
0
votes
2
answers
401
views
How is light unable to escape a black hole if photons are massless? [duplicate]
I understand light will follow the curved space that the BH is causing due to its mass. I also understand that mass attracts other mass but then photons are massless.
So 0(photon) x m2 (the BH) is ...
0
votes
1
answer
167
views
What actually is the mass? [closed]
Since high school, I've been told that the definition of mass is "quantity of matter" (which is absolutely wrong, I guess). If mass is actually a quantity of matter and it is a measure of ...
- 2,640
2
votes
4
answers
315
views
If a black hole has the same mass as me, then why dont i suck everything at my center of mass?
So, a black hole is very dense that you can get really close to its center of mass that it has a strong pull, well, if i have the mass of a black hole that has a really small event horizon, why doesnt ...
- 59
1
vote
1
answer
2k
views
If a black hole has a mass similar to a star, why does it have a different gravitational pull?
Say there is a black hole with 1 solar mass, having the sun's mass, it would have the same gravity as the sun, right? But it still has an event horizon, so why does it have such a strong gravitational ...
- 21
3
votes
1
answer
384
views
What if a primordial black hole went through the Sun?
How much mass would the Sun lose to a primordial black hole that (initially) has 10 Earth masses, passing through or close to the center of the Sun at solar escape velocity? How massive would the Sun ...
- 293
5
votes
2
answers
1k
views
GW190521 black hole merger total mass calculation and missing mass, how does this happen?
I have just read an article about that black hole merge event (it's in Italian):
Sette miliardi di anni fa, due mostri si unirono
What made me curious is that the article tell that a 66 solar mass ...
- 173
4
votes
1
answer
145
views
How do OGLE-III and GAIA measure the mass of free microlensing black holes?
What is the "hypothesized lower mass gap" between 2.5 and 5 solar masses? eventually links to Constraining the masses of microlensing black holes and the mass gap with Gaia DR2.
The angle of ...
- 30.7k
4
votes
3
answers
415
views
Could anything consume a small black hole?
Whenever I read about black holes, it is normally involving how they devour anything that comes too close... regardless of how big anything is.
But what if it were a really small black hole vs ...
user7845
0
votes
2
answers
608
views
Black hole's gravity
Is gravity relative to volume, or size of an object?
Since a black hole is a massive star that collapses on its weight, how comes the same sun's mass, when it becomes a black hole, provides gravity ...
- 41
-1
votes
1
answer
53
views
Mass of Photon and Black holes [duplicate]
The gravity caused by a black hole is said to be so strong such that even light(photons) can not escape from it. since gravity exist only in between objects with mass, How does a black hole attract a ...
- 183
1
vote
1
answer
109
views
Mass of a potential black hole in a binary system
So I've been given the velocity curve, parallax and apparent magnitude of a star in a binary system with what is potentially a black hole. I've calculated from the apparent magnitude and parallax that ...
2
votes
1
answer
687
views
Smallest mass of star to be a black hole? [duplicate]
It seems to me that I forgot the smallest mass of a star and its angular momentum in order to form a black hole.
So I know that electron degeneracy pressure is overcome if the core is 1.4 solar ...
- 1,872