Why Don't Black Holes Swallow All of Space?

[imhotep]

Black holes do a damn good job of swallowing everything. Then, why don't they just keep on expanding and expanding and simply swallow the Universe? A bit of a mind boggling question, isn't it?

Sometime ago the well known Stanford Physicist Leonard Susskind, who is one of the fathers of the "String Theory" provided an explanation.
He suggests that black holes expand by increasing in complexity inwardly – a feature we just don't see connected while watching from afar. In other words, they expand in, not out.

Weirder still, this hypothesis might have a parallel in the expansion of our own Universe, which also seems to be growing in a counterintuitive way.
Black holes aren't like ordinary space, so we can't expect ordinary rules to apply.

Details can be found on his "Three Lectures on Complexity and Black Holes" on the internet and also a printed book with the same name. Not for the average people though.

 

[Stimulus mind]

bump

 

[harindugamlath]

Bump. In any case Quasars are very interesting.

 

[Candid-B]

the closest black hole to earth is 'The Unicorn'. it lies 1500 light years away from us. it is said by the scientists that it 3 times larger than our sun. it would take 20000 years to get there by traveling speed of light.

 

[sam_sajith]

physics what we know does not exist in these, I think we are far from reality to discuss black holes, and hopefully space and time will be another dimension there, so all will move no further

 

[hodakolla]

BUMPER

 

[sam_sajith]

the closest black hole to earth is 'The Unicorn'. it lies 1500 light years away from us. it is said by the scientists that it 3 times larger than our sun. it would take 20000 years to get there by traveling speed of light.

1500 light years = 1500 years in speed of light to arrive close to our solar system
i think its the current speed of space will take 20000 years

 

[PHBhagya]

 

[Candid-B]

physics what we know does not exist these, I think we are far from reality to discuss black holes, and hopefully space and time will be another dimension there so all will move no further

they may be gateways to other galaxies. like wormholes

 

[fallend]

 

[Candid-B]

1500 light years = 1500 years in speed of light to arrive close to our solar system
i think its the current speed of space will take 20000 years

of course not. light wave travels at the speed of 1,079,252,849 km/h. so in a year (365*24=8760) 1,079,252,849*8760 = X
so, X*1500
=%^$^$#
so it would take around 20000 years to get there at a speed of light.

 

[imhotep]

Bump. In any case Quasars are very interesting.

BTW, did you notice the recent NASA photos from Hubble of a Double Quasar in merging galaxies.
https://www.nasa.gov/feature/goddard/2021/hubble-spots-double-quasars-in-merging-galaxies

 

[DjAnomaly]

people don't understand a shit about blackholes, how do they have zero volume, though they're bigger than our sun?

 

[NRTG]

BUMP

 

[sam_sajith]

of course not. light wave travels at the speed of 1,079,252,849 km/h. so in a year (365*24=8760) 1,079,252,849*8760 = X
so, X*1500
=%^$^$#
so it would take around 20000 years to get there at a speed of light.

Small clarification
One Light year = distance the Light travels within an earth year right ? so in that case 1500 light years means the distance light travels in 1500 years at speed of light ?

correct me if Im wrong, this is all about knowledge !
Thanks

 

[harindugamlath]

BTW, did you notice the recent NASA photos from Hubble of a Double Quasar in merging galaxies.
https://www.nasa.gov/feature/goddard/2021/hubble-spots-double-quasars-in-merging-galaxies

Wow! Thanks. Merging black holes in a young universes.

 

[Candid-B]

Small clarification
One Light year = distance the Light travels within an earth year right ? so in that case 1500 light years means the distance light travels in 1500 years at speed of light ?

correct me if Im wrong, this is all about knowledge !
Thanks

yes. I meant 'The Unicorn' black hole is 1500 light years away from the earth. that means the distance the light travels in a year multiplied by 1500. that means, 9.5tn KM * 1500 = X

 

[lovethebomb]

You need AdS CFT to make this speculation work. That's where I get a little less enthusiastic.

Also, this question: “why aren’t BHs expanding invasively?” always sounded off to me. Yes, the universe is quite old but BHs do not suck matter into them so ubiquitously. On top of that they can also decrease mass by way of radiation. So to say that BHs should be overbearingly large now is akin to saying that night sky should be brutally incandescent because there are immensely many stars in the universe.

If this is the case (which is boring I know), then event horizon is simply following the known Schwarzschild dynamics.

I admit though, this “inward expanding” next to the Hubble expansion which is “outward” looks really intriguing.

Unrelated comment...I might have my reservations about string theory but my god Lenny is such a good teacher when it comes to good old classical field theory. Everyone should read his “Theoretical Minimum” series. Especially people who are looking for a good entry point to the actual subject.

 

[imhotep]

You need AdS CFT to make this speculation work. That's where I get a little less enthusiastic.

Also, this question: “why aren’t BHs expanding invasively?” always sounded off to me. Yes, the universe is quite old but BHs do not suck matter into them so ubiquitously. On top of that they can also decrease mass by way of radiation. So to say that BHs should be overbearingly large now is akin to saying that night sky should be brutally incandescent because there are immensely many stars in the universe.

If this is the case (which is boring I know), then event horizon is simply following the known Schwarzschild dynamics.

I admit though, this “inward expanding” next to the Hubble expansion which is “outward” looks really intriguing.

Unrelated comment...I might have my reservations about string theory but my god Lenny is such a good teacher when it comes to good old classical field theory. Everyone should read his “Theoretical Minimum” series. Especially people who are looking for a good entry point to the actual subject.

I do not possess your knowledge in this area. However, the AdS/CFT correspondence is more than a decade old and it did revolutionize the way of thinking about quantum gravity.
There are many other theories too which came afterwards.

 

[ncpasan]