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View Full Version : Is matter destroyed forever in a black hole?



rtroxel
2014-Oct-31, 05:15 PM
Is matter being destroyed forever in black holes? If so, this would mean that the universe is losing matter constantly and in a few billion years will disappear altogether!

I realize that some astronomers feel that the matter is being sucked into another universe, but there is really no proof of that - yet.

Could we have a (humane) discussion about this?

Thanks,

Roy

Amber Robot
2014-Oct-31, 06:19 PM
It depends on what you mean by "destroyed". If the mass of the black hole increases, then the matter is still technically there.

Shaula
2014-Oct-31, 06:34 PM
Also it would take a lot longer than a few billion years to funnel all the matter in the universe into black holes. They actually feed quite slowly.

Solfe
2014-Oct-31, 07:02 PM
I guess it depends on what you mean by "destroyed" and "forever".

Seeing an asteroid go from a solid thing to plasma in a jet sounds pretty "destroyed" to me, and that doesn't even involve falling into a black hole. I am not sure if that qualifies for your "destroyed".

I am sort of up in the air about the forever part. Plasma in a jet seems to last a long time to me, but I doubt it will stay a plasma way forever.

Cougar
2014-Nov-02, 02:50 PM
Is matter being destroyed forever in black holes? If so, this would mean that the universe is losing matter...

Apparently not. When matter falls into a black hole, its gravitational effect does not "disappear." It's still there. That means the mass of that matter must still be there.


I realize that some astronomers feel that the matter is being sucked into another universe, but there is really no proof of that - yet.

I'm somewhat astounded that this speculative conjecture is given any serious consideration by the astronomical community. Apparently it arises from a purely analytical extension of Einstein's equations (a common "what if" exercise), which can lead to a "succession of asymptotically flat spacetime regions [within the black hole] that are inaccessible in the spacetime region in which the black hole first formed." Whether that describes "another universe," I don't know. I was going to say such a conjecture is unfalsifiable - not science - but just following the equations further, at least one of the possible solutions is falsified due to "quantum vacuum effects [that] cause an unbounded back-reaction which would smash the idealised interior geometry... demonstrat[ing] that the models which have been explicitly advanced to date cannot be taken seriously as space bridges." - source (http://www.nature.com/nature/journal/v272/n5648/abs/272035a0.html)

publiusr
2014-Nov-03, 08:05 PM
Over time--doesn't the mass energy lost by the matter just come back as hawking radiation?

antoniseb
2014-Nov-03, 08:23 PM
Over time--doesn't the mass energy lost by the matter just come back as hawking radiation?
No one has ever measured Hawking radiation, nor has the model been confirmed in other strong gravity ways, so the answer is that according the the current best model, yes.
This may be subject to change in the next few decades as we get better at observing black holes.

speach
2014-Nov-19, 10:34 PM
Lets think about the term "for ever" now this universe is around 14 billion year old. Is that "for ever". There must have been 'something' before, and it's going to last, I don't know' say 20 billion years more. Is that "for ever"? Does the word 'ever' mean no end and no beginning (starting to sound Biblical!). My interpretation of the word "ever" is just that no end no beginning.

Noclevername
2014-Nov-21, 06:29 AM
Lets think about the term "for ever" now this universe is around 14 billion year old. Is that "for ever". There must have been 'something' before, and it's going to last, I don't know' say 20 billion years more. Is that "for ever"? Does the word 'ever' mean no end and no beginning (starting to sound Biblical!). My interpretation of the word "ever" is just that no end no beginning.

Forever in this context, refers to the future, not the past.

Noclevername
2014-Nov-21, 06:30 AM
Also it would take a lot longer than a few billion years to funnel all the matter in the universe into black holes. They actually feed quite slowly.

And significant effort, since most mass is well outside the effective gravity wells of black holes, and so it could not "fall in" naturally.

Ken G
2014-Nov-21, 02:30 PM
I'm somewhat astounded that this speculative conjecture is given any serious consideration by the astronomical community. What's also odd is that in some people's views, these alternate universes, existing with "the bulk" surrounding ours, don't even have to obey the same laws as our universe does, or at least could have totally different attributes. I say, if you want to visit a universe where the laws or attributes are not like ours, you can save a lot of the energy needed to build wormholes by simply falling asleep and having a nice dream.