Current Theory of Cosmology

[dmill1220]

Hello everyone!
Please believe me! I, in no way intend to start a heated debate over this subject in any manner.
Im just looking for varied input on the Current theories out there, with any deviations from presently accepted theories,that anyone may have.
I would like to keep this friendly,and intuitive and in laymans terms that we can all understand, especially me! LOL!
I have heard of String theory, or M theory and the Multiverse theory,
the strange dark energy and its role in current cosmology.
the expanding and contracting or cyclic theories, are there more?
I even heard of one where things go from infinetly larger to infinetly smaller!
which one do you like the most and Why?
Dennis

[Dragon Star]

# Big Bang Theory

# Bubble Universe Theory

# Cyclic universe theory

# Recycled Universe Theory

# Clockwork universe theory

# Block Universe Theory

# Electric Universe theory

And it goes on and on and on...Big Bang and/or Multiverse Theory are what I think to be most likely. Both have more evidence and more support from direct observation then any-other theories as of now.

[dmill1220]

I personally Like the Multiverse and Cyclic theories, Cosmology does indeed have quite a few theories, To me its a fascinating Mix of possibilities.

It makes me feel Humble, sort of puts us in a perplexing Conundrum.
We really know very little of exactly How it was created, and where the Universe is headed. That to me is the fascinating part! the possibility that we could be completely wrong on all counts is really alluring.

With the little understanding that I have of this wonderful question, I can only rely on my intuition, but I lean to the ones I mentioned above. I dont like the Idea that it may expand forever and end up a cold place with dead Stars and Planets it a sad ending for me, but this also could be Correct!
Dont you wish we could zoom to the future just to see of we ever figure it out? I sure do! then again maybe its just one of those questions that can never be answered fully!
Dennis

[Blue Fire]

Good topic dmill! I don't think I'm knowlegeable enough to evalute a favorite cosmological theory, but I'll take a stab at a comment or two. I am currently fascinated by the idea of the Holographic Principle, as cursorily explained here in Wiki:

The holographic principle is a speculative conjecture . . . claiming that all of the information contained in a volume of space can be represented by a theory that lives in the boundary of that region. In other words, if you have a room then you can model all of the events within that room by creating a theory that only takes into account what happens in the walls of the room

and here:

Reasons for the holographic principle
Given any finite, compact region of space (e.g. a sphere), this region will contain matter and energy within it. If this energy surpasses a critical density then the region collapses into a black hole.

A black hole is known theoretically to have an entropy [1] which is directly proportional to the surface area of its event horizon. Black holes are maximal entropy objects [2], so the entropy contained in a given region of space cannot be larger than the entropy of the largest black hole which can fit in that volume.

A black hole's event horizon encloses a volume, and more massive black holes have larger event horizons and enclose larger volumes. The most massive black hole that can fit in a given region is the one whose event horizon corresponds exactly to the boundary of the given region.

Greater mass entails greater entropy. Therefore the maximal limit of entropy for any ordinary region of space is directly proportional to the surface area of the region, not its volume. This is counter-intuitive to physicists because entropy is an extensive variable, being directly proportional to mass, which is proportional to volume (all else being equal, including the density of the mass).

If entropy of ordinary mass (not just black holes) is also proportional to area, then this implies that volume itself is somehow illusory: that mass occupies area, not volume, and so the universe is really a hologram which is isomorphic to the information "inscribed" on its boundaries [3].

The key point here, for me anyway, is the finding that the entropy of a black hole is directly related to it's surface area rather than to volume. In any case, just the mere thought of what we think of as our universe being essentially illusory due to some kind of holographic effect projected (to represent the universe you and I observe) from an encompassing area boundary, seems so elegantly weird!

Another pet idea I entertain often is that there actually is a smallest chunk of space and a smallest chunk of time. I think this actually follows from the cosmological theory that all of spacetime exists at once and that you and I only experience a "forward" arrow of time as a consequence of traveling through spacetime in a particular "direction" at the speed of light, but in tiny steps from one state to another - sort of like how a movie proceeds one frame at a time. And so objects can move entirely through space but not time (like light), or entirely through time but not space (like someone standing motionless), or some combination of space/time vectors (like someone driving northeast whereby their motion is partly north and partly east).

I think having a smallest unit of time and a smallest unit of space would eliminate a lot of those nasty infinities that mathematical analysis of space and time currently has to deal with. Curiously, if this is so, then Zeno's Paradox is solved easily without resorting to analyzing either the logic or mathematics of traversing infinitely divisible distances.

Whew, that's all the brain matter I can spare at the moment. But I'm looking forward to other folks' posts here.

[Dragon Star]

Well we have a very good idea where it is going, and how it got to where it is, but how it started in the initial millionth of a second and before is clueless to us, because there truly are so many ways it could have happened it will be a very long time before we make sure we have the right one, but I will say that we will figure it out as long as we save our butts long enough to get there.

Read more on fate of the universe.

[Blue Fire]

Originally Posted by Dragon Star

[snip] but I will say that we will figure it out as long as we save our butts long enough to get there.

I concur!! But saveing our butts is a whole 'nother can of worms!! Let's take the optimistic view that we learn how to do this first before it's too late. *hoping, hoping, hoping*

[dmill1220]

HI Blue fire!
WOW! Thats a very interesting theory, that I dont think I ever heard of, but I like it! I really never thought of it in that Manner.
Dennis

[Dragon Star]

Oh, nice explanation on that theory Blue. Quite interesting indeed.

[dmill1220]

Hi Blue Fire!
I did some further research on the Holographic Principle theory that you pointed me to, its a fascinating idea!
it makes so much sense its wierd!

Time, is it not an invention of Man, in order to make sense of everthing we see or do?
Dennis

[Dragon Star]

Time is a tricky subject, as relativity comes to bite you in the butt. I would expand on it here but I think it deserves it's own thread. If someone would like to make it that would be nice.