Universe Question?

Joshua Jones

So been reading a bit on "The Big Bang" and black holes/singularities and both seem similar in the sense that both have a point of infinite mass. So my question is, Is it possible that we exist inside a black hole/singularity?.

im invisible

no.

Edit, i thought you said is it possible TO exist..., its not possible to exist inside a black hole, but i'll leave the question of DO WE exist inside a black hole to someone else

Anonymo

im invisible wrote: »

no.

Edit, i thought you said is it possible TO exist..., its not possible to exist inside a black hole, but i'll leave the question of DO WE exist inside a black hole to someone else

Bit of a contradiction in your reply im invisible - surely if we exist inside a black hole then it must be possible to exist inside a black hole! In any case as an answer to the original question ... a singularity refers to a point where our current understanding of physics breaks down. It may be possible that a better theory will explain the 'singularity'. Specifically in the case of a black hole or the big bang the singularity refers to a state where the density and energies are so high that a theory of quantum gravity which incorporates quantum mechanics and general relativity at such high energies. There is no such theory right now. All we know (as an observer) about black holes is up to the horizon - where light can no longer escape. To give you an example: if we observe somebody in free-fall towards a black hole we would think they never reach the horizon (since the light we see gets more and more redshifted near the black hole horizon). However, to the person in free-fall they would cross the horizon in a finite time. I presume this is the sort of thing you are wondering about ... of course it's obvious a human couldn't withstand the extreme tidal gravitational forces in a black hole but I'm guessing you're not asking that!

You may be interested in the following link
http://www.physorg.com/news/2011-04-russian-cosmologist-life-black-hole.html

Joshua Jones

I kind of find it hard too explain without having the proper language but here goes.
To my knowledge there is the theory that there may be other universes parallel to or own which can exist with completely different laws of physics to our own i.e a universe which contains energy but no matter.

Now our universe is expanding opposite to what was expected so therefore there must be energy/matter coming from somewhere to assist this expansion. So is it possible that a parallel universe created a rip in time/space where the energy/matter of the “super” universe created ours causing the big bang and expansion?.

From what I understand a black hole expands as it “absorbs” more matter/energy/other black holes so could the edge of our known universe be the event horizon of a black hole observed from the inside?.

Anonymo

Joshua Jones wrote: »

I kind of find it hard too explain without having the proper language but here goes.
To my knowledge there is the theory that there may be other universes parallel to or own which can exist with completely different laws of physics to our own i.e a universe which contains energy but no matter.

Now our universe is expanding opposite to what was expected so therefore there must be energy/matter coming from somewhere to assist this expansion. So is it possible that a parallel universe created a rip in time/space where the energy/matter of the “super” universe created ours causing the big bang and expansion?.

From what I understand a black hole expands as it “absorbs” more matter/energy/other black holes so could the edge of our known universe be the event horizon of a black hole observed from the inside?.

If you mean ... is it possible that our universe is the inside of a black hole of another parallel universe, then yes that is possible. So let's assume that is true. You state that our black hole/universe is expanding due to the accretion of matter in the parent universe. This is unlikely to be true. If it were we would be changing the constituents of energy over time. I guess this is possible but many of our predictions for the matter/energy constituents of the universe are borne out by observations of the CMB and of Supernovae. If we were accreting loads of energy then the CMB and Supernova would presumably not satisfy the same relations for energy.

However, the idea of the big bang and black holes being equivalent things is certainly one that has a lot of interest. If instead you assume that the formation of the black hole is due to the build up of a huge amount of matter/energy in the parent universe/black hole and then assume that this new black hole evolves as if it were a universe with energy constituents given by the parent then this is consistent with what we see. The accretion of matter onto the new black hole would probably then just have to be a small perturbation - too small to appreciate.

Hope I haven't confused you!

Joshua Jones

Anonymo wrote: »

If you mean ... is it possible that our universe is the inside of a black hole of another parallel universe, then yes that is possible. So let's assume that is true. You state that our black hole/universe is expanding due to the accretion of matter in the parent universe. This is unlikely to be true. If it were we would be changing the constituents of energy over time. I guess this is possible but many of our predictions for the matter/energy constituents of the universe are borne out by observations of the CMB and of Supernovae. If we were accreting loads of energy then the CMB and Supernova would presumably not satisfy the same relations for energy.

However, the idea of the big bang and black holes being equivalent things is certainly one that has a lot of interest. If instead you assume that the formation of the black hole is due to the build up of a huge amount of matter/energy in the parent universe/black hole and then assume that this new black hole evolves as if it were a universe with energy constituents given by the parent then this is consistent with what we see. The accretion of matter onto the new black hole would probably then just have to be a small perturbation - too small to appreciate.

Hope I haven't confused you!

No that makes sense and is exactly what I wanted to know.

So, would our Universe obey the same laws as the parallel universe or could they be different?.

Anonymo

Joshua Jones wrote: »

No that makes sense and is exactly what I wanted to know.

So, would our Universe obey the same laws as the parallel universe or could they be different?.

The laws/physics of the new universe are set by the matter/energy that constitutes the new universe - we can assume that GR will remain the same (albeit governed by different Newtonian constants etc.). The expansion rate for example will be different due to different energy compositions. However, I guess what you're asking is - do we inherit the fundamental constants like the Newtonian constant, electromagnetic coupling, speed of light, etc from our parent universe. I'm pretty sure that we do inherit these but I've not thought about it deeply. One reasone that different universes would have different laws is because they are seeded by different realisations of the string theory landscape (each with possibly different physical constants). Since black hole universes born within particular black holes etc can be thought of as originating from the same seed as the parent universe I can't see how their fundamental constants could be different. Again this is just me thinking aloud so don't take this as fact!

Joshua Jones

Anonymo wrote: »

The laws/physics of the new universe are set by the matter/energy that constitutes the new universe - we can assume that GR will remain the same (albeit governed by different Newtonian constants etc.). The expansion rate for example will be different due to different energy compositions. However, I guess what you're asking is - do we inherit the fundamental constants like the Newtonian constant, electromagnetic coupling, speed of light, etc from our parent universe. I'm pretty sure that we do inherit these but I've not thought about it deeply. One reasone that different universes would have different laws is because they are seeded by different realisations of the string theory landscape (each with possibly different physical constants). Since black hole universes born within particular black holes etc can be thought of as originating from the same seed as the parent universe I can't see how their fundamental constants could be different. Again this is just me thinking aloud so don't take this as fact!

Yeah that's what I was thinking, logically the new universe would have the same constants as the seed universe. Just wondered if you could think of any reasons for an exception. Thanks for the replies they were very helpful.

Joshua Jones

Another one, (I do my best thinking in bed lol).

Is it possible for two parallel universes to come into contact i.e for a rip to appear between the two and energy/matter to be transferred from one to the other. Now if this is possible then would it also be possible, that with both universes having different laws and constants, to form completely different laws and constants when they mix i.e like mixing two colours together to get a third, blue+yellow=green.

Now this part probably wont be touched as physicists are loath to talk about anything before the big bang but could one universe have had the matter and energy we are made of/can detect and the other universe contain dark matter/energy and when they coalesed gave us the universe we inhabit now. Or is this just crazy talk?.

Anonymo

Joshua Jones wrote: »

Another one, (I do my best thinking in bed lol).

Is it possible for two parallel universes to come into contact i.e for a rip to appear between the two and energy/matter to be transferred from one to the other. Now if this is possible then would it also be possible, that with both universes having different laws and constants, to form completely different laws and constants when they mix i.e like mixing two colours together to get a third, blue+yellow=green.

Now this part probably wont be touched as physicists are loath to talk about anything before the big bang but could one universe have had the matter and energy we are made of/can detect and the other universe contain dark matter/energy and when they coalesed gave us the universe we inhabit now. Or is this just crazy talk?.

the way to think about parallel universes coming into contact is like bubbles coming into contact (that don't burst of course!). The universe with its different physics will look to those inside the universe it's colliding with like a nucleating bubble. The wall of this bubble separates the different phases (us and the universe colliding with us). If its energetically favourable the wall of this bubble will expand out at (close to) the speed of light, and this bubble may come to encapsulate all of our universe. In other words there would be a phase transition (like water freezing to form ice) from our current state with its laws to the state in the energetically favoured colliding universe. Of course this would wipe out the stuff that was there already! So to answer your question you cannot pick and choose bits from one universe to add to the other.

Btw physicists are not 'loath to talk about things before the big bang'. In fact they are more than happy to do so. However, the caveat is that the predictivity of such theories is almost non-existent. I'm a physicist and I'm answering your questions!

Joshua Jones

Anonymo wrote: »

the way to think about parallel universes coming into contact is like bubbles coming into contact (that don't burst of course!). The universe with its different physics will look to those inside the universe it's colliding with like a nucleating bubble. The wall of this bubble separates the different phases (us and the universe colliding with us). If its energetically favourable the wall of this bubble will expand out at (close to) the speed of light, and this bubble may come to encapsulate all of our universe. In other words there would be a phase transition (like water freezing to form ice) from our current state with its laws to the state in the energetically favoured colliding universe. Of course this would wipe out the stuff that was there already! So to answer your question you cannot pick and choose bits from one universe to add to the other.

Btw physicists are not 'loath to talk about things before the big bang'. In fact they are more than happy to do so. However, the caveat is that the predictivity of such theories is almost non-existent. I'm a physicist and I'm answering your questions!

Thanks, appreciate your time.

Anyway I was just trying to understand dark matter/energy. I know it constitutes about 3/4 of the known universe and for something to be so plentiful yet totally unknown to us is weirdly strange lol. I kinda got into the notion that maybe it was here before the big bang, kinda like agar jelly, then our universe (observable) "grew" in it.

Although I think this is going into QM and I remember watching a documentary one time about a guy labeled "The father of QM" and he said "if someone tells you they understand QM then they're lying" or something to that effect. So as a layman I wouldn't know where to start lol.