Open Space Indeed--Questions For A Variety of 'Astronomers'

[Evenstar]

If in ~ a trillion years the universe pulls itself apart into 'nothing' which I gather will include pulling apart atoms and subatomic particles... what will happen to black holes where all the matter that has entered ceases to exist because space/time gets caught up in a singularity of 'nothing'? Will the event horizons disappear? If everything else atomic has ceased to exist does this include dark energy and dark matter too? And one assumes all the galaxy and super galaxy clusters making up these amazing filaments in our universe are all gone as part of that atomic breakdown? It seems to me that even if everything is gone that we know of there will be an awful lot left in the boundary of our universe left that we know nothing about.

One of my most difficult problems as a layperson who barely touches calculus let alone quantum physics I have is how to appreciate the known universe with no boundary edge or center where this 'big bang' happened ~ 13 billion years ago?

Why call it dark energy and dark matter if we haven't a clue yet what it is? Why not call dark matter 'dark gravity' since it seems to account for glue holding astronomical mass together? Why not call dark energy 'dark acceleration' since it seems to be what upsets the balance of this attraction causing galaxies to be accelerating further away from each other?

I thought I read that the voyager spacecraft escaping our solar system but not through the Oort Cloud by any means yet are accelerating for some unknown reason since there is no thrust produced by the spacecraft themselves? Could this be dark energy / acceleration at work?

[Evenstar]

How can anything be called matter or energy just because what we think is missing matter and energy is unaccounted for if you can't see or detect that matter or energy? By calling it matter and energy are we limiting ourselves by 'defining' something we know nothing about just because we need these 'factors' to make the math work? Does it HAVE to be matter and energy we end up discovering or could what we are missing, once discovered, negate needing this mass and energy?

[geckzilla]

You might get a better response if you take it a bit more slowly and stay with one topic at a time. But anyway, I'm not sure why it takes such a stretch of imagination to hypothesize the existence of certain matter which doesn't interact with the EM spectrum. If it really exists, which it probably does, then it's mysterious by nature so don't expect to ever understand it intuitively or for it to ever stop being mysterious. I think photons are bloody weird but I don't deny they exist.

[Beyond]

Yeah, those little buggers(photons)know when you're watching them and they behave differently.
Hmm... i never quite thought of them as a life-form before.

[Evenstar]

You might get a better response if you take it a bit more slowly and stay with one topic at a time. But anyway, I'm not sure why it takes such a stretch of imagination to hypothesize the existence of certain matter which doesn't interact with the EM spectrum. If it really exists, which it probably does, then it's mysterious by nature so don't expect to ever understand it intuitively or for it to ever stop being mysterious. I think photons are bloody weird but I don't deny they exist.

Got to try a second reply here--sorry. Why didn't the first one to your reply post--can't find it anywhere after hitting 'Submit'? So what did I say? That I don't expect any one person to reply to all my questions but only to what catches their fancy/interest/expertise. I admit I'd like nothing better then to get the whole chaotic universe and life to line up in some intuitive fashion avoiding quantum physics and the like so that's got to be partly why I've got to live in a 3 dimensional world and universe that has edges and centers to it. I'm pretty comfortable letting space and time disappear into a singularity though.

[Chris Peterson]

If in ~ a trillion years the universe pulls itself apart into 'nothing' which I gather will include pulling apart atoms and subatomic particles... what will happen to black holes where all the matter that has entered ceases to exist because space/time gets caught up in a singularity of 'nothing'?

It will be a LOT more than a trillion years. Black holes will eventually go away. Remember that matter and energy are just two forms of the same thing. When matter is lost in a black hole, the mass remains, and that means the energy is still there. Black holes radiate away energy, both because they are warmer than absolute zero, and because of quantum effects at their event horizons. The process is slow, but with enough time even the most massive black holes evaporate. In this scenario, the ultimate fate of the Universe is to end up a diffuse sea of photons, electrons, neutrinos, and a few other particles, with no heat gradients left- thermodynamic equilibrium forever.

If everything else atomic has ceased to exist does this include dark energy and dark matter too?

Dark energy isn't atomic. It isn't matter. In the future, the total amount of energy in the Universe remains unchanged from today. It doesn't cease to exist.

One of my most difficult problems as a layperson who barely touches calculus let alone quantum physics I have is how to appreciate the known universe with no boundary edge or center where this 'big bang' happened ~ 13 billion years ago?

We know exactly where the Big Bang occurred. It occurred at (0,0,0,0). We can't access that point today because we are at t>0, and unlike the spatial dimensions, we can't move backwards in the time dimension.

Why call it dark energy and dark matter if we haven't a clue yet what it is? Why not call dark matter 'dark gravity' since it seems to account for glue holding astronomical mass together? Why not call dark energy 'dark acceleration' since it seems to be what upsets the balance of this attraction causing galaxies to be accelerating further away from each other?

Don't confound dark matter and dark energy. Outside of the fundamental matter-energy equivalence, they are completely different things. Science starts with observations. We observe dark matter in numerous ways by the way it influences energy and matter around it. In many respects, it behaves like other matter. We already have examples of particles that don't interact, or only interact very, very weakly with the electromagnetic force (neutrinos). So there is good reason to theorize that dark matter is just that- non-baryonic matter. Dark energy is simply the name given to an observed phenomenon. The name isn't important; the observation is. That dark energy is poorly understood simply reflects the nature of science as a process of increasing knowledge.

I thought I read that the voyager spacecraft escaping our solar system but not through the Oort Cloud by any means yet are accelerating for some unknown reason since there is no thrust produced by the spacecraft themselves? Could this be dark energy / acceleration at work?

No spacecraft are obviously experiencing forces that can't be explained by conventional physics. You are thinking here of the Pioneer anomaly, very slight unexpected accelerations observed in the Pioneer 10 and 11 spacecraft once they were near the edge of the Solar System. This has since been explained (very accurately) by modeling thermal radiation from the spacecraft, which creates an acceleration due to the momentum of photons.

[Evenstar]

Regarding Pioneer 10 and 11... interesting. I never read of the explanation before. So the Voyager spacecraft experienced this same thermal radiation/acceleration? These photons are radiating toward the Sun thus accelerating spacecraft ever so slightly away from the Sun.

I don't feel I can work my questions further nor understand your answers well without much more study. Thank you.

From recent 'How the Universe Works: Expanded Edition' I get that Black Holes are weird! ...and will hold that thought.

[Infrapace]

You are looking at light as only EMR,the same as you perceive a wave form in the frequency domain.
Light when looked as a particle behaves quite differently.See light bending by gravitation as was predicted.
Same as frequency in the Time domain. It can be different beast.

[lookinside1]

Disclaimer: I claim no expertise in the sciences.

That said, when dark matter and
dark energy caught my attention, it seemed obvious that they products of the evolution of black holes. They also seem to prove the idea that they are part of electromagnetic spectrum that we haven't the senses or science to detect. Is this being studied? By who? Thank you for any replies.

[geckzilla]

Disclaimer: I claim no expertise in the sciences.

That said, when dark matter and
dark energy caught my attention, it seemed obvious that they products of the evolution of black holes. They also seem to prove the idea that they are part of electromagnetic spectrum that we haven't the senses or science to detect. Is this being studied? By who? Thank you for any replies.

I don't think anything you've said is obvious at all. There may be some relationship or there may be none at all. You could try browsing or searching arXiv for papers on whatever topic interests you. https://arxiv.org/list/astro-ph.CO/current