Ask Me Help Desk - Absolute 0

So, this isn't really a question. Just some thoughts I have had. Disclaimer, I am a layman never formally study physics, but it is something I have always been interested. Please forgive me and correct me where ever I am wrong.
I have been watching a couple different documentaries and read a couple different books. They have ranged in topics, but specifically I have been curious about two things in particular. Absolute 0 and the end of the universe. For instance, one documentary was talking about the cooling of liquid helium to just a nano kelvin above absolute zero. How the helium then behaves quantum mechanically and all of the helium behaves as one entity. Really interesting stuff in its own right. Here is a link for a clip of the documentary.
http://www.youtube.com/watch?v=9FudzqfpLLs
The second part of my thoughts were concerning the expansion of the universe and eventual end. How all galaxies are moving away from all other galaxies. Eventually even stars within a galaxy will start to move apart and then planets etc all the way down atoms themselves moving away. Essentially, how I am interrupting this is that the universe is approaching absolute zero. The energy density of the entire universe will gradually get closer and closer to 0. Am I wrong here, because what this tells me is that if we combine these two ideas of a substance close to absolute 0 behaves quantum mechanically, as "one" and the universe expands to the point where it is uniformally nearly absolute zero. I suppose this is where my question is. What does this actually mean? I see it as kind of a default reset that the universe is operating as the singularity it was in the beginning and everything would start over. These are kind of lofty ideas, but I am curious to see what an actual physicist would say.

Quote:

Originally Posted by bweezie

So, this isn't really a question. Just some thoughts I have had. Disclaimer, I am a layman never formally study physics, but it is something I have always been interested. Please forgive me and correct me where ever I am wrong.
I have been watching a couple different documentaries and read a couple different books. They have ranged in topics, but specifically I have been curious about two things in particular. Absolute 0 and the end of the universe. For instance, one documentary was talking about the cooling of liquid helium to just a nano kelvin above absolute zero. How the helium then behaves quantum mechanically and all of the helium behaves as one entity. Really interesting stuff in its own right. Here is a link for a clip of the documentary.
Ben Miller experiments with superfluid helium - Horizon: What is One Degree? - BBC Two - YouTube
The second part of my thoughts were concerning the expansion of the universe and eventual end. How all galaxies are moving away from all other galaxies. Eventually even stars within a galaxy will start to move apart and then planets etc all the way down atoms themselves moving away. Essentially, how I am interrupting this is that the universe is approaching absolute zero. The energy density of the entire universe will gradually get closer and closer to 0. Am I wrong here, because what this tells me is that if we combine these two ideas of a substance close to absolute 0 behaves quantum mechanically, as "one" and the universe expands to the point where it is uniformally nearly absolute zero. I suppose this is where my question is. What does this actually mean? I see it as kind of a default reset that the universe is operating as the singularity it was in the beginning and everything would start over. These are kind of lofty ideas, but I am curious to see what an actual physicist would say.

Hi bweezie,

I'm not a physicist, but I do have it somewhere in the back of my mind there is a theory that the heat death of the universe will resemble the beginning of the universe.

Unfortunately I can't remember who came up with this theory, but I am sure it is taken seriously in cosmology.

Tut

I am not a physicist, but if I am not wrong, you have spoken about two different ends: the first (where everything starts going apart) is called Big Rip, in which for each atom its observable universe is empty (i.e. every other atom stays outside). The second scenario, in which the Universe continues its expansion, and II law of thermodynamics does its job, is called Big Freeze (or heat death). These two scenarios involve very different timescales.

The second scenario can be grossly reassumed as follows: due to II law of thermodynamics, Universe will have lower and lower energy density, thus lower and lower gradients (which naturally diminishes in a closed system).

As for the quantum part, unfortunately I do not remember anything. Will the Universe at some point recreate an enormous gradient (maybe due to quantum effects) is entirely uncertain.

Quote:

Originally Posted by Aurora2000

I am not a physicist, but if I am not wrong, you have spoken about two different ends: the first (where everything starts going apart) is called Big Rip, in which for each atom its observable universe is empty (i.e. every other atom stays outside). The second scenario, in which the Universe continues its expansion, and II law of thermodynamics does its job, is called Big Freeze (or heat death). These two scenarios involve very different timescales.

The second scenario can be grossly reassumed as follows: due to II law of thermodynamics, Universe will have lower and lower energy density, thus lower and lower gradients (which naturally diminishes in a closed system).

As for the quantum part, unfortunately I do not remember anything. Will the Universe at some point recreate an enourmous gradient (maybe due to quantum effects) is entirely uncertain.

Hi Aurora,

Yes, two quite different fates for the universe. I can't be 100 percent sure but I think it is the second scenario I was thinking about. I would look it up but I don't know where to look.

Perhaps I misunderstood the theory. From memory it seems to be claiming that the universe will eventually experience a heat death. A reasonable assumption given that the universe is accelerating. Every point is moving away from every other point. If this goes unchecked the universe will reach absolute zero.

Given the liquid helium experiment there is a claim that at extremely low temperatures matter starts to behave in a odd way. Going on my limited understanding, the people conducting the experiment on the U tube clip seem to be claiming there is some type of quantum entanglement going on. Although this is not stated directly. "Spooky action at a distance" as Einstein would say.

It was then I remembered this particular Big Freeze/Singularity Theory. It would strike everyone, including myself that this is counter intuitive. A Big Freeze can't be a Singularity and a Singularity cannot be a Big Freeze

In quantum terms a very tiny distance (Planck length) is required for space time to be subject to quantum effects. Once ( assuming one day it will) the universe has reached absolute zero then distance is irrelevant in quantum terms. There is no difference between a Plank length and 15 billion light years. Matter will behave like it would at tiny distances provided it is cold enough.

Perhaps it is possible to show how the two dissimilar states exhibit a similar type of symmetry. As said, I really can't remember the theory so I better apologize to the person who came up with it just in case I am reading a whole lot of stuff into it that isn't really there.

Is there a quantum physicist out there that can help?

Tut

Hi Tut,

Thank you for the quantum part.

Thank you all for your responses they have helped me process my own thoughts a bit more. I suppose what I am suggesting is that apparently, when something is cooled extremely low quantum effects manifest themselves on a macro scale. So, if they whole universe experiences a "Big Freeze" how would it behave? What are the implications of the whole universe not being contained in the metaphorical plug (referencing the video)?