Fate of Universe revealed by galactic lens

[Tank]

Thanks for that most interesting and enlightening post Hack. I will have a look at the book recommendation.

As you point out discovering the mechanisms that underpin gravity/DM/DE would be a remarkable step forward and hopefully the LHC will shed light on these mechanisms.

[karadan]

Lots of awesome

 :hail:

[Will]

Okay everybody, we have a few trillion years to figure out how to stop heat death.

And... go!

[Asmodean]

Eh... Only took us a... Vell, very short time to figure out how to stop life, so how hard can it be?! We just... Just... Errm... ..! Build the opposite of a gun and shoot dead people with it!  

[Will]

No, no, heat death. The theory is, eventually, the universe will reach maximum entropy. We've gotta stop it because the universe will become uninhabitable. Maybe we can trigger the big crunch.

[Asmodean]

No, no, heat death. The theory is, eventually, the universe will reach maximum entropy. We've gotta stop it because the universe will become uninhabitable. Maybe we can trigger the big crunch.

Uninhabitable, eh..? Well, we'll just have to make the opposite of the mother of all destructions  

[deekayfry]

I remember reading a time line of the heat death of the universe.  It is discomforting.  We think of existence as infinite, but there is an end point and it will be reached because the universe has all the time it needs to settle down and die.

[Ultima22689]

Well, if any force in this universe can stop the heat death, I guarantee you it's the human race. I think the human race or whatever we will have become over time will be more than capable of doing so, I sincerely doubt we will reach any cataclysmic disaster if one does not happen in the next decade or so because by then the human race may become impossible to extinguish thanks to our technology. I believe there is merit to the law of accelerating returns and I am a transhumanist, I believe the singularity will come sometime in this century. I can't even imagine what we will be like in over a few trillion years but the human race will surely dwarf any "god" we thought up in the past or present. SCIENCE FTW!

[hackenslash]

I think you're overestimating the abilities of humans. Our influence on the universe is piddling, and will almost certainly remain so. More importantly, decrease in entropy requires the input of energy, and is therefore only achievable on a local level. The input of energy at a local level necessarily increases entropy overall. Every time we do work of any kind, we make energy unavailable to do work, which is the definition of entropy. What this means for our ability to reverse heat death is simple. We can't.

[karadan]

We might be able to escape heat death by jumping to younger universes, though.

[Ultima22689]

Sure. I am overestimating humans if we're thinking of them in terms of the standard Homo Sapien. I'm thinking of creatures one with their own technology completely erasing the line between their biology and technology. The majority of the population thinking with all the ambition and creativity of the human race but with the ever rapidly evolving computational power and perfection of a machine. New theories we've never thought of or wouldn't think of because of math beyond our brain's capabilities to process quickly or comprehend much at all will become child's play as we run equations through our heads millions of times every second.

Although I would imagine that we may sooner figure out how to leave our universe before we can actually stop it's expansion but you never say never, physics isn't absolute, considering the phrase dark matter is just a place holder who knows what we will eventually learn about the universe. in a couple of years we could have to rewrite everything we know about physics.

[karadan]

As soon as AI starts upgrading itself to the point of Matrioshka brain status, anything and everything will be possible. Links between universes will be a walk in the park
By that point humans will live their lives as pure energy anyway.

[hackenslash]

Just a couple of points, in the interest of a little rigour.

Sure. I am overestimating humans if we're thinking of them in terms of the standard Homo Sapien. I'm thinking of creatures one with their own technology completely erasing the line between their biology and technology. The majority of the population thinking with all the ambition and creativity of the human race but with the ever rapidly evolving computational power and perfection of a machine.

This is wishful thinking, to be honest. Even given huge technological mastery, the sheer scale of the cosmos is an issue.

New theories we've never thought of or wouldn't think of because of math beyond our brain's capabilities to process quickly or comprehend much at all will become child's play as we run equations through our heads millions of times every second.

This is a misunderstanding of the possible future capabilities of the human brain, and I think it seriously doubtful that we will evolve much more capacity than we already have. It may certainly be possible to have  neural implants, increasing our capacity, but there are physical limitations to how large our brains can grow naturally. More imortantly, though, it isn't clear that the kind of neural implants we're talking about are even possible, for all sorts of reasons, not least the simple fact that all our brains are wired completely differently. If your brain were downloaded and implanted into mine, it would make absolutely no sense, because your synaptic connections are all radically different from mine. I'm not ruling it out, but it's important to be aware of the limitations.

Although I would imagine that we may sooner figure out how to leave our universe before we can actually stop it's expansion but you never say never,

ACtually, I can, although I suspect that this is simply a non-rigorous use of the word 'universe'. There is no way to leace the universe, because there is no outside the universe. The universe is literally all that exists. Of course, it may be that you are employing the word in the sense of that which arose from the big bang, in which case, I refer you to my earlier comments about our cosmos being a closed system.

physics isn't absolute, considering the phrase dark matter is just a place holder who knows what we will eventually learn about the universe. in a couple of years we could have to rewrite everything we know about physics.

That's doubtful. Rewriting everything we know about physics would require that we've missed something fundamental. Our current physical theories are immensely accurate, so they are definitely giving us the right picture. The picture is incomplete at the moment, but our best theories are definitely right. The two remaining questions in physics that really matter are the unification of General Relativty and Quantum Mechanics (or answering the question of why they may not be unified) and describing what gravity actually is. These two questions can actually be stated to be one and the same. If we discover the graviton or the Higgs particle, then both questions are answered and we can work toward a quantum theory of gravity, which is really the last piece in the puzzle. All areas in physics, whether relativistic mechanics, quantum mechanics or particle physics, are all geared toward fitting this final piece into the puzzle. Much of the rest will be, I suspect, mopping up the details.

As for the comment about dark matter being a place holder, this doesn't mean that there's something fundamental that we've missed, or that there is something missing from our theories. It just means that there is matter out there that doesn't reflect or emit radiomagnetic energy. There's nothing exotic about it, we just can't see it.

[Dretlin]

As Professor Farnsworth said: "Evacuate the Universe!"

[Tanker]

It is kind of eerie to think that in a few trillion years, there will be nothing other than black holes and red dwarfs floating about the cosmos.

It's all about perspective. Is it not more eerie to think in just a few decades there will be nothing, as far as we care, in the universe? There you go a much more depressing thought. The univese is practically timeless compared to eyeblick we exist through. The universe wll continue to exist long after heat deat,h it will just be alot more boring.