Saturday, April 26, 2008

Why our time dimension is about to become space-like

"Good Morning.
While you were sleeping,
the world as you knew it ceased to exist."

Sitting on the fringe of the quantum foam,
listening to the 11 dimensional humm...

(Is so much easier than doing the math.)

It don’t get much weirder than this. The universe is about to lose its dimension of time says a group of theoretical astrobods at the University of Salamanca in Spain. And they got the evidence to prove it.

The idea comes from the study of braneworlds: the thinking that the universe we see around us is a 4-dimensional cosmos called a braneworld embedded in a multidimensional universe. The “signature” of our universe is the number of space and time-like dimensions it has: in our case we got 3 space-like dimensions and one time-like dimension. It’s what astrobods call a Lorentzian universe. So far so good: lots of astronutters think the same thing.

But our universe may not always have been like this. Some theorists think it may once have had a Euclidean signature meaning that all the dimensions were space-like. Now Marc “Bars” Mars and a few pals in Spain say that the Universe’s signature might be about to flip from Lorentzian to Euclidean. In other words, our dimension of time is about turn space-like. Gulp!

This ain’t entirely bonkers and here’s why. Bars Mars has calculated what it’s like to be an observer in a universe that is about to flip and get this: it would look as if it were expanding and accelerating away from us. Sound familiar?

Yep, it’s exactly what astrobods have been observin over the last few years, a phenomenon they attribute to dark energy. If Bars Mars is right, dark energy ain’t got nothing to do with it and we’re all starin’ down the barrel of a cosmic catastrophe.

Still, maybe four space-like dimensions will be better than three. Who needs time anyway?

Ref: Is the Accelerated Expansion Evidence of a Forthcoming change of Signature?

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