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Bigemptybrain
2008-Nov-07, 11:20 PM
Hi, I'm new to all this so I hope i'm in the right place to be asking a question, or should I say request some discussion, on the question of an ever expanding universe. If we view that energy and matter are the same thing in a different form and we take the amount of energy and matter we can see and set those results aside. If we could then measure all of the dark matter and dark energy(being the same thing). It would be cool if these two ratios(matter:energy against dark matter:dark energy) corolated to one another in some way. And, then would it all add up to enough for there to be enough mass to slow the expansion down and eventually make it contract. I remember reading somewhere some guy worked out the magic figure that there needs to be so much mass for this to happen. I know the observation is that the universe is accelerating its expansion but can we assume for a minute that our observation is distorted in some way and we are wrong thinking that it is accelerating at this rate and these results are infact from the past. Or, we are in an accelerarory stage that at some time in the future will slow down.

sabianq
2008-Nov-08, 12:13 AM
I personally don't believe that it is ever expanding.
seems to go against the laws of thermodynamics.

this is what i believe is happening

the universe started as a collision between vast high energy dimensions, the collision happens like the ocean collides with the shore or like oil and water.
this produces a foam of universes. each tiny bubble of foam is its own universe, each taking up its own space, in its own dimension, its own time.
a foam of universes permeate the bigger universe that all of this happens in.
the universe (single bubble int the foam) is born, has a life, and dies. like everything in the universe.

it expands and grows like a bubble, then bursts, (bang) like a balloon popping, the contents of that universe accelerate into the lower energy/density void of the all encompassing big universe, then slow down and finally come to rest, all the matter in that universe loses its energy and dies a cold and slow death, mass just winds down, the energy holding everything together just eventually runs out.
Subatomic particles lose their spin and decay back into what they were before the collision that gave them their energy happened.
then and everything is just recycled back to the foam again.

and it just keeps happening, has always happened, always will.

my very general take.

I would bet that if we can see far enough, we would see the galaxys slowing down, depending on where we are in the life cycle of our universe....

Hornblower
2008-Nov-08, 01:30 AM
I personally don't believe that it is ever expanding.
seems to go against the laws of thermodynamics.

this is what i believe is happening

the universe started as a collision between vast high energy dimensions, the collision happens like the ocean collides with the shore or like oil and water.
this produces a foam of universes. each tiny bubble of foam is its own universe, each taking up its own space, in its own dimension, its own time.
a foam of universes permeate the bigger universe that all of this happens in.
the universe (single bubble int the foam) is born, has a life, and dies. like everything in the universe.

it expands and grows like a bubble, then bursts, (bang) like a balloon popping, the contents of that universe accelerate into the lower energy/density void of the all encompassing big universe, then slow down and finally come to rest, all the matter in that universe loses its energy and dies a cold and slow death, mass just winds down, the energy holding everything together just eventually runs out.
Subatomic particles lose their spin and decay back into what they were before the collision that gave them their energy happened.
then and everything is just recycled back to the foam again.

and it just keeps happening, has always happened, always will.

my very general take.

I would bet that if we can see far enough, we would see the galaxys slowing down, depending on where we are in the life cycle of our universe....
Can you show us, in appropriate mathematical detail, why you think your idea explains the observations better than does the standard model?

If you are serious, perhaps you should ask the mods to move this to ATM. Then it can be debated at length without confusing novices who wish to learn some fundamentals here in Q&A.

PraedSt
2008-Nov-08, 01:36 AM
If you are serious, perhaps you should ask the mods to move this to ATM. Then it can be debated at length without confusing novices who wish to learn some fundamentals here in Q&A.

Yes, Sabianq, this is fine at the ATM section, not here!

this produces a foam of universes. each tiny bubble of foam is its own universe, each taking up its own space, in its own dimension, its own time.
a foam of universes permeate the bigger universe that all of this happens in.

sabianq
2008-Nov-08, 01:37 AM
sure, lets move it to atm so i wont get in trouble anymore.
:)

but i did not think that mainstream had a good answer as to why the universe is expanding.

can anybody say what dark energy is anyway?

Ken G
2008-Nov-08, 01:41 AM
Mainstream science does not need to say why the universe is expanding. It knows the proper place of science, that's why it's mainstream. The goal is to understand the expansion, the rules it obeys, not why it exists. Much progress has been made on the former, and little so far on the latter. Wild speculation adds little to that state of affairs, though it may be fun to partake in.

Hornblower
2008-Nov-08, 01:46 AM
sure, lets move it to atm so i wont get in trouble anymore.
:)

but i did not think that mainstream had a good answer as to why the universe is expanding.

can anybody say what dark energy is anyway?

The idea of dark energy was very much ATM initially, and we still do not know what it is, but the mainstream scientists have scrutinized it and have not found anything better. Once again, can you show us mathematically how your idea is supposed to work better?

The cosmos is what it is and does what it does, and it does not care whether or not fallible mortal human beings like ourselves think it makes sense.

sabianq
2008-Nov-08, 01:50 AM
so i have a question to ad to the op

how does the standard model explain the expansion of the universe?
what exactly is dark energy and why does it seem that it violates the second law of thermo dynamics? (stating that the entropy of an isolated system which is not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.)

how can something just keep accelerating forever?

i am just suggesting/wondering that/if eventually everything will slow down and reach a state of equilibrium.?

PraedSt
2008-Nov-08, 01:51 AM
sure, lets move it to atm so i wont get in trouble anymore.
:)

It's the newbies who we're worried about. :)

You'll be fine.

sabianq
2008-Nov-08, 01:56 AM
i guess my idea would work better because it is not based on what i perceive as perpetual energy. things wind down, and die, particles decay, stars burn out..

does the current model suggest/predict that the universe will stop expanding?

if it does, then i am in error thinking it does not suggest that.

sabianq
2008-Nov-08, 02:06 AM
its loosy based on the cyclic model including The Steinhardt-Turok model and m-theory

http://en.wikipedia.org/wiki/Cyclic_model

In this cyclic model, two parallel orbifold planes or M-branes collide periodically in a higher dimensional space. The visible four-dimensional universe lies on one of these branes. The collisions correspond to a reversal from contraction to expansion, or a big crunch followed immediately by a big bang. The matter and radiation we see today were generated during the most recent collision in a pattern dictated by quantum fluctuations created before the branes. Eventually, the universe reached the state we observe today, before beginning to contract again many billions of years in the future. Dark energy corresponds to a force between the branes, and serves the crucial role of solving the monopole, horizon, and flatness problems.

however as As Richard C. Tolman showed, the earlier cyclic model failed because the universe would undergo inevitable thermodynamic heat death which i feel compelled to concur with.

which leads me to think it is a combination of many of the models

this isnt my original idea...

sabianq
2008-Nov-08, 02:59 AM
i forgot to mention its roots in "bubble theory"

http://en.wikipedia.org/wiki/Multiverse#Multiverse_hypotheses_in_physics

Bubble theory posits an infinite number of open multiverses, each with different physical constants. (The set of bubble universes is thus a Level II multiverse.)

The bubble universe concept involves creation of universes from the quantum foam of a "parent universe." On very small scales, the foam is frothing due to energy fluctuations. These fluctuations may create tiny bubbles and wormholes. If the energy fluctuation is not very large, a tiny bubble universe may form, experience some expansion like an inflating balloon, and then contract and disappear from existence. However, if the energy fluctuation is greater than a particular critical value, a tiny bubble universe forms from the parent universe, experiences long-term expansion, and allows matter and large-scale galactic structures to form.

yes, as quoted from wiki "these theories lack empirical correlation and testability, and without hard physical evidence are unfalsifiable;"

however m-theory, string theory and quantum gravity all seem to support each other.
http://en.wikipedia.org/wiki/Quantum_gravity#CITEREFGreenSchwarzWitten1987

sabianq
2008-Nov-08, 03:10 AM
I know the observation is that the universe is accelerating its expansion but can we assume for a minute that our observation is distorted in some way and we are wrong thinking that it is accelerating at this rate and these results are infact from the past. Or, we are in an accelerarory [sic]stage that at some time in the future will slow down.

i am just suggesting that the acceleration we see that we think is caused by some form of hypothetical form of dark energy:
http://en.wikipedia.org/wiki/Dark_Energy

In physical cosmology, dark energy is a hypothetical exotic form of energy that permeates all of space and tends to increase the rate of expansion of the universe.

may indeed be something that we don't quite understand yet.

i suggested that maybe, according to the second law of thermodynamics, the universe will eventually slow down and maybe even just stop altogether.

PraedSt
2008-Nov-08, 03:20 AM
Sabianq. It's nice that you're so enthusiastic, but how about giving the OP a chance to respond? :)

sabianq
2008-Nov-08, 03:23 AM
Sabianq. It's nice that you're so enthusiastic, but how about giving the OP a chance to respond? :)

u are absolutely 100% correct.

Cheap Astronomy
2008-Nov-09, 08:38 AM
Hi bigemptybrain,

Getting back to your question... :-)

Certainly the observations that led to the current view that the universe is expanding are from the past - as all astronomical observations are. Sure the situation could be different 'now', but we have no way to confirm or refute that.

I understand you are suggesting that the dark energy viewed 'then' might have converted into mass 'now'. Can't see any way to confirm or refute that either, although most conversion of (known) energy to mass occured in the very early stages of the universe.

I understand that current thinking on dark energy is that it represents a form of vacuum energy - and is hence ephemeral in nature - albeit the cumulative effect of lots of ephemeral quantum fluctuations is increased as the universe expands (i.e. more vacuum). This is the thinking behind why it doesn't violate thermodynamics (usual complaint is that it violates the first law) and why the universe could expand forever.

The whole point of the word dark is that we know sod-all about it and can only speculate based on the scanty evidence available. Less theorising and more evidence gathering seems the best way forward at present.