Dark mater and the multiverse?

[Fishteacher73]

Cosomolgy and theoretical physics are not my strogest suits, but I do finf it intersting, so pehaps my question/thought is already answered out there.

I was speaking with my brother and he was saying that with the discovery that the expansion of the universe was increasing and they had calculated that aproximatly 95% of the universe's mass would have to be dark matter to "fuel" this expansion.

Another scrap of info that I have recently seen was that through microwaves (If I recall, it may have been some other sort of dectection) that if we trace back to emmissions that date in the 13-14 billion year age that we essentailly reach a wall of plasma that we can not penetrate with any imeans of observation (Yet).

While I have seen the concept of a multiverse with universes like bubbles in a boiling pot. Would it be reasonable to attibute the expansion rate to real matter/energy in these other univeses as opposed to this "phantom" of dark energy and matter?

[RiverRat]

Are you saying the expansion is related to the attraction of our entire universe to another universe (ie … our universe is (+) and other nearby universes are (-) … like being stretched) or that matter from other nearby universes are spewing into ours ‘physically’?

I would tend to think that if matter was crossing universal boundaries physically, we would theoretically be able to detect it ???

Dumb question ... Does our universe overall have a charge ???

[maddog]

Fish,

I think you are speaking of the distribution of the kinds of matter in the universe. Yes, recent evidence
from survey indicate that on one hand (method) the universe is Very Flat, while other evidence shows
that the amount of matter in the universe if about 5%. By studies of gravitational lensing show about
22-25% for dark matter. The remaining is the really weird "dark energy" that is thought to be driving the
inflation portion of the expansion. Any boundry you speak of is the horizon where to see further you
have to have been around before the begining. Since the light from any object further than the boundry
would take longer than the universe was in existence. NASA & JPL have been using 13.7 Billion as the
current age now that the latest microwave background ratiation (MBR) has been corroberrated with
Globular Clusters luminosity (few years back there was independent evidence that some Globular
CLusters of nearby Galaxies were older than the Galaxy they were going around.

Oh, I see you were talking about this "wall" as MBR. Well yes before that models are used to predict
what happened. No direct evidence has yet been found.

Multiverses are somewhat of a different topic. Also depends on the old concept by Wheeler where each
universe was its own bubble, or a recent Sci Am article about a year ago mentions the BB wasn't so big
that any such crunch isn't so final. The end product is oscillating unverse where each new bang creates
a new expansion inside of the old one.

Maddog

[Buffy]

The canonical article on Multiverses is Andre Linde's article in Scientific American in 1994, which you can download here: http://www.stanford.edu/%7Ealinde/1032226.pdf

Its my favorite on the topic, and he's the guy principally responsible for the whole concept...

Cheers,
Buffy

[Aki]

Originally Posted by Fishteacher73

While I have seen the concept of a multiverse with universes like bubbles in a boiling pot. Would it be reasonable to attibute the expansion rate to real matter/energy in these other univeses as opposed to this "phantom" of dark energy and matter?

Dark energy and dark matter are two opposite things. While dark energy causes the universe to expand, dark matter (like ordinary matter) tries to stop/ slow down the expansion due to gravitational force.

[Fishteacher73]

Originally Posted by RiverRat

Are you saying the expansion is related to the attraction of our entire universe to another universe (ie … our universe is (+) and other nearby universes are (-) … like being stretched) or that matter from other nearby universes are spewing into ours ‘physically’?

I was wondering if just the mass of these other universes could be streaching us gravitationally. No real cross over of material.

Maybe thare has been some emperical evidence that I have not been privy to (Most of my exposure to this realm of science is mainly popular sources, Nova,etc.) that supports dark mater/energy. As it seems now is that iit is a mathmatical construct to allow our theories to continue to work.

[bumab]

I was wondering that too. It seems like the accelerating expansion is going on just as one would imaging gravitational acceleration towards some giant, unknown thing outside (and around) the observable universe. Of course, it would have to be attracting space itself, not just the mass in it...

[lindagarrette]

Originally Posted by Buffy

The canonical article on Multiverses is Andre Linde's article in Scientific American in 1994, which you can download here: http://www.stanford.edu/%7Ealinde/1032226.pdf

Its my favorite on the topic, and he's the guy principally responsible for the whole concept...

Cheers,
Buffy

I remember reading that article years ago and thought there might be something to it but I haven't heard of any solid evidence to support or reject it.