the universe is not ageless/eternal

[Eastoff]

http://www.technologyreview.com/blog/arxiv/27793/?ref=rss

In recent years, however, cosmologists have begun to study a number of new ideas that have similar properties. Curiously, these ideas are not necessarily at odds with the notion of a Big Bang.

For instance, one idea is that the universe is cyclical with big bangs followed by big crunches followed by big bangs in an infinite cycle.

Another is the notion of eternal inflation in which different parts of the universe expand and contract at different rates. These regions can be thought of as different universes in a giant multiverse.

So although we seem to live in an inflating cosmos, other universes may be very different. And while our universe may look as if it has a beginning, the multiverse need not have a beginning.

Then there is the idea of an emergent universe which exists as a kind of seed for eternity and then suddenly expands.

So these modern cosmologies suggest that the observational evidence of an expanding universe is consistent with a cosmos with no beginning or end. That may be set to change.

Today, Audrey Mithani and Alexander Vilenkin at Tufts University in Massachusetts say that these models are mathematically incompatible with an eternal past. Indeed, their analysis suggests that these three models of the universe must have had a beginning to

 

[Fez Hammersticks]

The Universe is still expanding -- shouldn't the 'big bang theory' kinda prove this already?

 

[jlprk]

"In recent years"--there is nothing recent about the ideas which follow that. Scientists have contemplated them for over a century, and Hinduism long before that.

What is recent is that the formerly science fiction idea of dimensions got a lot of mathematical treatment when acid users became middle-aged scientists. The multiverse is now cutting edge science with a lot of developed math. There may be parallel universes, some eternal and some with beginning points.

What is new in this poorly-explained article is that someone has some math claiming that either all universes are finite or all are infinite in time. They can't be mixed. Next year someone else will come up with math opposing this. This dialectic is how science progresses.

 

[crowTrobot]

misleading. their work does not address multiverse models, only models where our visible universe is eternal in some sense (cyclical etc.). Vilenkin himself is largely responsible for the idea of eternal inflation within our visible universe, so he's contradicting his own idea here.