Was the Early Universe 2 Dimensional Spacetime? 309
astroengine writes "According to two theoretical physicists, our current four-dimensional Universe (3 dimensions of space, 1 dimension of time) is actually an evolution from a lower-dimensional state. The early Universe may have existed with just one spatial dimension (plus one time dimension) up until the Universe cooled below an energy state of 100 TeV. At this point, a transition occurred when the spatial dimension "folded" to create 2 dimensions. At 1 TeV, it folded again to create the Universe we know today: 3 dimensions of space, one of time. This may sound like a purely theoretical study, but there might be evidence of the evolution of universal dimensions in cosmic ray measurements and, potentially, in gravitational wave cut-off frequency."
Re:Physicists (Score:3, Insightful)
s/see what we'll buy/get the world to notice them/
Re:Physicists (Score:5, Insightful)
It doesn't matter what one buys or likes. Nature doesn't give a damn about opinions. It's just the way it is and that's it. Either scientists find data to back that hypothesis up and it explains data better than other attempts or not. But whether one finds it crazy or not is completely irrelevant.
Flatland? (Score:2, Insightful)
With regards to 2 D universe in the early universe, "Flatland" was from 1884. Err... 1884 is "early universe" to this 5 digit UID, you lower digit UIDs probably think of 1884 as your middle age.
http://www.gutenberg.org/ebooks/97 [gutenberg.org]
Re:The Cameron Divide (Score:5, Insightful)
"The Lucas Shift" is when it went to being 'far, far, away'.
And the acting went from 3D to 2D.
Re:Physicists (Score:3, Insightful)
Re:Physicists (Score:5, Insightful)
Actually, in my twenty-plus years as an academic, the theoretical physicists I've known and occasionally played cards with are among the most grounded and sensible people. They are not weed-smoking crazies.
If you want to meet the really whacky impractical "crazy-for-the-sake-of-crazy" folks, you have to go to the economics department. Especially since the rise of the contrary-for-no-good-reason "Freakonomics". Those are people who should not be driving cars. They should also not be calling themselves "Science" but that's a discussion for another day.
Not the physicists (Score:5, Insightful)
Re:Physicists (Score:0, Insightful)
Those are people who should not be driving cars. They should also not be calling themselves "Science" but that's a discussion for another day.
Yes, everyone should go with the herd. Being contrary and questioning things is unmutual. Questions are a burden to others; answers are a prison for oneself. Be seeing you.
Re:Nope that's Science Fiction Authors (Score:4, Insightful)
No, it doesn't sound anything like it. One is a theory about things that happen at Big Bang levels of energy, the other is an author putting the words "space" and "fold" together.
Re:Time. (Score:4, Insightful)
It cannot be modelled mathematically unless it involves statistics, which physicists hate to admit becasue it means no tractable solutions for real General Relativity problems exist.
Time is no dimension, but if you don't mind a little uncertainty, you can pretend it is.
Not that crazy... (Score:5, Insightful)
We might imagine the universe is starting with a very large amount of energy compressed into singularity and then it starts expanding by inflating dimensions. You can assume that there are as many dimensions as you want, but that they are very small; not infinitely small, but small enough so that a complete circuit of the dimension is much smaller than a Planck length. The dimensions are expanding to create a place to put all that energy, so we might expect that one dimension would inflate significantly before it runs out of space - literally - and the next one would start to inflate in earnest. So to expand out and get the three big dimensions we have now, you would naturally pass through a stage where we have 1 and then 2 dimensions. If this happened, we should be able to see the tell-tale signs still imprinted in the make-up of the current universe. For instance, events that happened at very high energies (from early universe), should look today like they all happened in a line or plane instead of in 3D space. That is what the paper is about - more ways to check for this..
BTW, the reason inflation mostly stops after 3 dimensions is that three dimensions is the lowest number of dimensions where randomly distributed items are no longer on top of each other. (e.g., a 1d or 2d random walk will always return to its origin, but in 3D you can get lost for good). You can also hypothesize that a few more dimensions also expanded a little in the process, but not by very much. This is (very) basically what string theory holds.
Many people have trouble understanding the relationship between how many dimensions you have, how much you can hold, and the energy levels involved. Here is a simple thought experiment that anyone can do with just a pen and paper or maybe a string. We will use the paper for space and the string for energy. Draw a 1" line. How long of a piece of string can it "hold"? Only an 1" of course. Now draw a 1"x1" box. How long of a piece of string can it hold? About 1.4", if you stretch it from corner to corner. Now make a 1"x1"x1" box. How long of a piece of string can it hold now?
You can actually stick the Empire State Building into a 1" n-dimensional cube, as long as n is sufficiently large (I think around 225 million should do it...