May 25, 2007

How will our Universe die?

An interesting theory has emerged which predicts that trillions of years into the future, the information that currently allows us to understand how the universe expands will have disappeared over the visible horizon. All that will remain will be "an island universe" made from the Milky Way and its nearby galactic Local Group neighbors. What's left will be a dark and lonely void.

The theory was put out by physicists Lawrence Krauss from Case Western Reserve University and Robert J. Scherrer from Vanderbilt University. Their research article, titled, "The Return of the Static Universe and the End of Cosmology," will be published in the October issue of the Journal of Relativity and Gravitation.

This brings to mind a number of different theories in the field of cosmological eschatology.

The Big Crunch

The work of Krauss and Scherrer stands in sharp contrast to another end-state theory, namely the Big Crunch. In this model, the momentum of the Big Ban will eventually wane causing the Universe to collapse in on itself. But due to the recent revelation that the Universe is not just expanding but that its expansion is speeding up, newer theories have suggested that the Universe will continue to expand forever.

The Big Rip

This has lead to some rather bizarre conclusions, including the emergence of a theory known as the Big Rip. According to this theory, the Universe will start to expand at such a rapid rate that all its elements, from galaxies to atoms, will be torn apart by the extreme expansion rate of the Universe. This is scheduled to happen about 20 billion years from now.

The force that is causing the Universe's matter to push outwards is what's known as dark energy. This is why galaxies are moving away from each other -- and why they will continue to do so until gravity will be too weak to hold them together.

Eventually, in the final months of the Universe, our solar system will be gravitationally unbound. In the last minutes, stars and planets will be torn apart. And in the Universe's final spastic salvo all atoms will be destroyed.

Heat Death

Another possibility is the Heat Death of the Universe, also known as The Big Freeze. In this model the Universe would continue to expand forever, but it would enter into a state of maximum entropy in which all matter and energy is evenly distributed; consequently, there would be no 'gradient' to the Universe -- a characteristic that is needed to sustain information processing, including life.

Other theories

Other possibilities include the False Vacuum, where the laws and constants of the Universe are subject to radical change, and various multiverse theories in which the cosmos is expressed in a infinite number of iterations for an infinity.

Another more radical possibility is that the future of the Universe will be influenced by intelligent life. Theories already exist in regards to stellar engineering -- where a local sun could be tweaked in such a way as to extend its lifespan. Future civilizations may eventually figure out how to re-engineer the Universe itself (such as re-working the constants) or create an escape hatch to basement universes.

Thinkers who have explored this possibility include Milan Cirkovic, John Smart, Ray Kurzweil, Alan Guth and James N. Gardner.

Read more here.


Hoka-shay-honaqut said...

The "Island Universe" is attractive for the infinite universe believer, as well, because any subsequent "bangs" and inflations beyond the horizon will not interact with this current space. Indeed, the current bang could be beyond the horizon of a "previous" universe.

mw said...

What I find interesting about some of these theories is the singular direction of their scenarios.

If we regard the universe as a system, then surely its parameters - and hence their inherent functionalities - must be applicable across the entire time line. There may be various scales, moving the phenomena from energy relationships to their counterparts in matter and so on, but the underpinning system ought to remain the same.

When it comes to life processes, the best analogy I have come across is autocatalytic closure. Here we have a system that lets phase states emerge out of its own pool of properties. These properties may manifest at different scales but are nevertheless subject to the bounds established by that system.

It can be shown this works when transposing the phenomenon into cognitive abstractions, and it certainly works for polymers. If and when differing manifestations occur they can still be related back to the original set of parameters. (Think of carbon: molecules > life forms > humans > industry > emissions > back to carbon; all within the confines of our planet)

To postulate a scenario in which the universe ‘disappears’ somehow, leaves the question of those underpinning parameters unanswered.

Since I am not a physicist I cannot even begin to suggest what those parameters might be. However, what strikes me about autocatalytic closure in those settings I have been able to examine (and yes, understand) is the sheer universality of its occurrence. It applies to polymers; you can find it in the emergent complexity of the central nervous system; it works when it comes to the system of mind and its ongoing abstractions.

Why couldn’t it be something fundamental to reality as such?

Anonymous said...

Of boredom..... or perhaps nanopsychopathology

Anonymous said...

Well, i think it was pretty neat, although what's with all the "Big" theories? like, the "Big Bang" and the "Big Freeze", and the "Big Crunch" and the "Big Rip"? C'mon, i know the universe is infanite, but can we atleast try to be more creative in our last trillion years of life?