Black Hole theory

[hoppa]

" One theory states that if two people were standing on the outside of the event horizon, and one of them stepped over:
1)To the person standing outside the horizon, it would appear that the one who had crossed had instantly disappeared, being drawn to the point of singularity
2)To the person who had crossed, time would appear to stop, and they would be able to see the person on the outside forever frozen in time

How the heck do you explain" that?? "

that makes no sense. light has no problem going in to the black hole (and therefore to the person inside), its getting out that is the problem. if there is actually a theory that states that, there must be an explanation asscociated with it. i'd like to hear it.

 

[zugzoog]

Originally posted by: hoppa
" One theory states that if two people were standing on the outside of the event horizon, and one of them stepped over:
1)To the person standing outside the horizon, it would appear that the one who had crossed had instantly disappeared, being drawn to the point of singularity
2)To the person who had crossed, time would appear to stop, and they would be able to see the person on the outside forever frozen in time

How the heck do you explain" that?? "

that makes no sense. light has no problem going in to the black hole (and therefore to the person inside), its getting out that is the problem. if there is actually a theory that states that, there must be an explanation asscociated with it. i'd like to hear it.

The explantion is from Relativity. One of the results of the theory of relatively was the realistion that Mass affects time, in fact mass slows down time. The effects of this have been measured and verified IIRC the USAF synchroised two atomic clocks and then flew one of them at high altitude for a period of time. When the clock was returned to the groud there was a time difference between the two clocks that fitted within the experimental error.

As black holes have a very large mass, the closer you get to the black hole the more distorted time becomes, hence the effect that you have described.

Note that this is a form of time travel. If you wanted to go forward in time, hang around the edge of a black hole for a little while and when you come out more time has passed in the universe than the time that you have spent in the black hole (this is, of course, with the proviso of you having a power source sufficient to escape the black hole edge and you surviving the gravitational differential attempting to rip you and your spaceship apart).

 

[zugzoog]

Originally posted by: DoC91383
Is there actually PICTURES of a blackhole? I've never actually known if they are real or myth. And if they are real has anyone actually provided evidence of something passing through it doens't come out the other side?

Pictures of a black hole is something of an oxymoron. How can you take a picture of something that does not allow light to escape it....? 😕

They can be inferred however... Link, and there may be some direct evidence that they exist, although this is yet to be confirmed link

 

[Looney]

Originally posted by: Geniere

Present data now indicates the universe does not contain enough mass to contract. It now appears near certain the universe is expanding at an accelerated rate. The end result will be cold, black, and lifeless, no nuclear reactions, no chemical reactions, no nothing.

It's actually more confusing than that... we believe the universe should contain more matter than we really see, because otherwise galaxies would be flying apart... this missing matter is called Dark Matter, because it must be something we can't see or even detect.

But what's really confusing, is that the universe is expanding at a faster rate than we think... and actually accelerating. So now we're missing something called Dark Energy... something that is causing the universe to accelerate forward, but we don't know what it is.

 

[Looney]

Originally posted by: DoC91383
Is there actually PICTURES of a blackhole? I've never actually known if they are real or myth. And if they are real has anyone actually provided evidence of something passing through it doens't come out the other side?

There sure are pictures of blackholes... not direct pictures of them, since it's black, and light can't escape from it (which is why it's black. But blackholes have been observed when stars/galaxies pass behind one, and their light gets blocked.

 

[imported_jb]

Originally posted by: Hardcore
...Dark Energy...

can't anyone just assume its expanding from the big bang? matter still being propeled from the initial blast?


and to clarify my previous post:
yes i made that up. i am saying that some particles or something must be created at the edges of the universe, as it expands.

 

[Looney]

Originally posted by: jb

Originally posted by: Hardcore
...Dark Energy...

can't anyone just assume its expanding from the big bang? matter still being propeled from the initial blast?


and to clarify my previous post:
yes i made that up. i am saying that some particles or something must be created at the edges of the universe, as it expands.

Expanding, yes... but it's ACCELERATING. And for something to accelerate, there needs to be a force that is causing it to accelerate.

 

[Pohemi]

Originally posted by: jb

Originally posted by: Hardcore
...Dark Energy...

can't anyone just assume its expanding from the big bang? matter still being propeled from the initial blast?


and to clarify my previous post:
yes i made that up. i am saying that some particles or something must be created at the edges of the universe, as it expands.

But if it started from a point of singularity, or a marble, so to speak...if new matter had to be created to keep expanding and filling the universe, wouldn't it be created at the center where the Big Bang originated? I'm not sure I understand the logic there...😕

 

[imported_jb]

by "it started from a point of singularity, or a marble", you mean the big bang?
i'm picturing a center point, and an arrangement of stars (at first) forming outwards.

just seems that matter would be created at the edges. and probably relatively evenly.

 

[Pohemi]

If the matter was travelling outwards though (expanding the edge so to speak), the vacancy in space would be at the point of origin, so if new matter had to be created (out of nothing) I would imagine it'd be created at the point of origin, not along the imagined edge of space which is already being filled by matter moving outwards.

I don't think matter can just be created out of nothingness in order to fill empty space is my point, so I don't quite understand how you imagine this happening.

 

[itachi]

Black holes don't "suck" things in any differently than the earth "sucks" things downwards. It's just gravity. In fact, if you compressed the sun down to a radius of 1.48 km it would turn into a black hole. We would continue to orbit the sun at our current orbit and everything would be just as it is, except it'd be dark.

i think we'd be kinda dead too.. no sun, no heat.. ice.

Pictures of a black hole is something of an oxymoron. How can you take a picture of something that does not allow light to escape it....? 😕

i was thinking the same thing..

point of singularity, with respect to the big bang theory, is the universe before it became the universe. the ball of mass with no dimensions, a single point.

i'm kinda wonderin about this too now.. einstein theorized that mass and energy are intechangeable.. if mass were created at the edges of the universe then wouldn't the density of energy there have to be greater than anywhere closer to the center? and if it were denser, what's keeping the universe from reaching an even dispersion of energy? i kinda remember learning something related to this some years ago..

i have no idea wtf i'm talkin about.. 😕

 

[Pohemi]

Originally posted by: itachi

i have no idea wtf i'm talkin about.. 😕

:thumbsup: Ha ha, me too pretty much but I am at least smart enough to think about it, LOL :laugh:

 

[rymaster]

Hell anyone who is smart enough to think about these things should truly be thankful. I find nothing more fascinating then space. To relate to the black hole theory, I like to think that everything it collects it spits out of a white whole, maybe a whole different universe? To relate to the expanding of the universe, the only thing I can think about is how that one single point got there :-\

 

[Looney]

Originally posted by: Pohemi420

Originally posted by: jb

Originally posted by: Hardcore
...Dark Energy...

can't anyone just assume its expanding from the big bang? matter still being propeled from the initial blast?


and to clarify my previous post:
yes i made that up. i am saying that some particles or something must be created at the edges of the universe, as it expands.

But if it started from a point of singularity, or a marble, so to speak...if new matter had to be created to keep expanding and filling the universe, wouldn't it be created at the center where the Big Bang originated? I'm not sure I understand the logic there...😕

New matter/energy is not created... what we see in the universe, is what we've had since the very beginning of the big bang. It's taken different form of course due to fusion in the sun, but it's the same amount.

 

[Looney]

Originally posted by: rymaster
Hell anyone who is smart enough to think about these things should truly be thankful. I find nothing more fascinating then space. To relate to the black hole theory, I like to think that everything it collects it spits out of a white whole, maybe a whole different universe? To relate to the expanding of the universe, the only thing I can think about is how that one single point got there :-\

This is one of Hawking's theory... he even wrote a book on it called Black Holes and Baby Universes... he believes that black holes create or leads to baby universes. But if it just dumped matter into another universe, then how does a blackhole increases in size? A black hole increases in size because the singularity is more dense, and it's more dense because more matter is going into it, so it has a larger gravitation force... but if it's just ejecting everything into another universe, then it shouldn't grow. But we know there are different sizes of blackholes... with the center of galaxies having HUGE ones.

 

[Gibsons]

I've a question regarding Hawking radiation and the "evaporation" of black holes.

As I understand it, sometimes in a vacuum two virtual particles come to exist, a particle and an anti-particle. When this happens close to a black hole, particularly a small one, one particle can sometimes cross the event horizon and the other can escape. For some reason though, the anti-particle is more prone to be sucked into the black hole than the particle, so over time, the black hole loses mass (radiates it, sort of). Is this right? If so, why the bias between particles and anti-particles?

 

[Looney]

No, anti-particles are not more prone to be sucked into blackholes... they're both equally are likely. Except when an anti-particle escapes, it'll eventually collide with a normal particle and be destroyed. But if a positive particle escapes, it will eventually become a real particle, and to become that real particle, requires the energy from the anti-particle... which ineffect creates a debt in the blackhole. If we were observe these particles from the blackhole, we would see positive particles shooting out of the blackhole as real particles.

Or another way... if a anti-particle escapes, it will eventually destroy itself by colliding with normal particle. But the positive particle that goes into the blackhole, never becomes a real particle, because it's other half has been destroyed. So when a positive particle goes into the blackhole, it doesn't add or decrease the blackhole mass. But when an anti-particle goes into the blackhole, it does reduce the blackhole mass.

Confusing? Yeah, it can be. But if you google for Hawking's Radiation, i'm sure there are others that can explain it much better than i can.

 

[imported_jb]

Originally posted by: Pohemi420
If the matter was travelling outwards though (expanding the edge so to speak)...

i highly doubt matter is travelling outwards. the "outside" area of the universe must grow exponentially every second. just energy.. the energy from the collisions on the edge should create matter.
anyways, now that sounds like too much energy, as the need for it too would grow exponeteially every second w/ area. jeez.. think it's just expanding from the light of the big bang?

back on topic:
someone should change the name to blackball or something. blackhole is way too misleading.

 

[Pohemi]

Originally posted by: jb

Originally posted by: Pohemi420
If the matter was travelling outwards though (expanding the edge so to speak)...

i highly doubt matter is travelling outwards.

The universe is expanding, is it not? I was referring to the universe expanding outwards from the theoretical origin of the Big Bang.

😉

 

[r00tcause]

One theory states that if two people were standing on the outside of the event horizon, and one of them stepped over:
1)To the person standing outside the horizon, it would appear that the one who had crossed had instantly disappeared, being drawn to the point of singularity
2)To the person who had crossed, time would appear to stop, and they would be able to see the person on the outside forever frozen in time

How the heck do you explain that??

Easy. Time slows down the for accelerating object and remains constant for the outside observer. The difference is all in the perspective. To one traveling near light speed it would seem as if everything had stopped and it would take an infinite amount of time to reach the "singularity". The outside observer would simply see you disappear as soon as you crossed the horizon from which light cannot escape. However, the light reflecting off him is being sucked in with you, and so you can still view him, in slow motion. In theory.

 

[r00tcause]

and to clarify my previous post:
yes i made that up. i am saying that some particles or something must be created at the edges of the universe, as it expands.

How exactly would these particles be created?

 

[r00tcause]

Originally posted by: Hardcore

Originally posted by: rymaster
Hell anyone who is smart enough to think about these things should truly be thankful. I find nothing more fascinating then space. To relate to the black hole theory, I like to think that everything it collects it spits out of a white whole, maybe a whole different universe? To relate to the expanding of the universe, the only thing I can think about is how that one single point got there :-\

This is one of Hawking's theory... he even wrote a book on it called Black Holes and Baby Universes... he believes that black holes create or leads to baby universes. But if it just dumped matter into another universe, then how does a blackhole increases in size? A black hole increases in size because the singularity is more dense, and it's more dense because more matter is going into it, so it has a larger gravitation force... but if it's just ejecting everything into another universe, then it shouldn't grow. But we know there are different sizes of blackholes... with the center of galaxies having HUGE ones.

Hawking wised up and recently came out and said he was wrong. Now he agrees with me. Its about time. 😉

 

[InseName]

first of all, black holes only form from giant stars, and the grvitational pull is the same as the previous star's pull, (people think its greater since u can get closer to it, which will allow it to pull it harder) so as things are right now, we are not nociably moving towards any one large star, so if any star were to change to a black hole, there would be absolutly no change....

 

[zugzoog]

Originally posted by: zugzoog

Originally posted by: hoppa
" One theory states that if two people were standing on the outside of the event horizon, and one of them stepped over:
1)To the person standing outside the horizon, it would appear that the one who had crossed had instantly disappeared, being drawn to the point of singularity
2)To the person who had crossed, time would appear to stop, and they would be able to see the person on the outside forever frozen in time


How the heck do you explain" that?? "

that makes no sense. light has no problem going in to the black hole (and therefore to the person inside), its getting out that is the problem. if there is actually a theory that states that, there must be an explanation asscociated with it. i'd like to hear it.

The explantion is from Relativity. One of the results of the theory of relatively was the realistion that Mass affects time, in fact mass slows down time. The effects of this have been measured and verified IIRC the USAF synchroised two atomic clocks and then flew one of them at high altitude for a period of time. When the clock was returned to the groud there was a time difference between the two clocks that fitted within the experimental error.

As black holes have a very large mass, the closer you get to the black hole the more distorted time becomes, hence the effect that you have described.

Note that this is a form of time travel. If you wanted to go forward in time, hang around the edge of a black hole for a little while and when you come out more time has passed in the universe than the time that you have spent in the black hole (this is, of course, with the proviso of you having a power source sufficient to escape the black hole edge and you surviving the gravitational differential attempting to rip you and your spaceship apart).

My apologies, upon rereading your original question I note that I have slightly misread it, however my answer is still valid.

You stated that the theory predicted;
1)To the person standing outside the horizon, it would appear that the one who had crossed had instantly disappeared, being drawn to the point of singularity
2)To the person who had crossed, time would appear to stop, and they would be able to see the person on the outside forever frozen in time

When in fact (or "in theory") the following would occur

1)To the person standing outside the horizon, it would appear that for the one who had crossed time would slow down dramatically, and they would be able to see the person on the inside almost frozen in time
2)To the person who had crossed, he/she will instantaneously be drawn to the point of singularity.

 

[imported_jb]

Originally posted by: r00tcause

... i am saying that some particles or something must be created at the edges of the universe, as it expands.

How exactly would these particles be created?

i discussed this more in my 01/06/2005 04:02 PM post.