DARK ENERGY AND THE EXPANSION OF THE UNIVERSE – WHAT IS TO BECOME OF US?

WMAP image of the (extremely tiny) anisotropies in the cosmic background radiation (Photo credit: Wikipedia)

Where are we headed? Cosmologists don’t know for sure, but they’re trying to find out. 

Recently, I went to the latest FREE physics dialogue at the Aspen Center for Physics -- “The Universe Caught Speeding: the Mystery of Dark Energy,” given by Dr. Dragan Huterer , Associate Professor of Physics at the. It was a great follow-up to the May 24th Aspen Center for Physics lecture, “TheDynamic and Evolving Universe”. 

As predicted, based on my experience at previous Aspen Center for Physics lectures, I came away with more questions than answers, but I did learn a lot as well. 

Dr. Huterer’s Presentation

 

In the presentation, we learned that it was once believed that the shape of the universe would dictate its future. This holds true, however, only if the universe is comprised of matter exclusively. 

This theory of “Geometry is destiny”, which acknowledges the existence of Dark Matter as well as regular matter, relies on several assumptions, one of which is that gravity is the ONLY large range force that exists.

Actual observations, however, have cast doubt on the assumption that that gravity is the only large range force in existence and suggest that the universe is NOT made up of matter only. 

In the 1990’s, cosmologists and astrophysicists theorized and discovered observationally through the study of distant supernovae and several other methods, that the expansion of the universe is in fact accelerating and that some repulsive large range force must be causing it to do so.

PHYSICS IN ASPEN - “THE DYNAMIC AND EVOLVING UNIVERSE”

Hubble - infant galaxy (Photo credit: Wikipedia)

Last week I attended the first Summer 2012 Free physics dialogue hosted by the Aspen Center for Physics , “The Dynamic and Evolving Universe”. This presentation was given by Dr. GilHolder, Associate Professor of Physics at McGill University . 

As is usual for me in regard to these kinds of presentations, I have come away with more questions than answers – but I guess that’s the nature of scientific inquiry. 

We were presented with a lot of details, but were given three main takeaways:

1. The universe is expanding at an increasing rate. 
   
2. This is occurring despite the fact that the force of gravity is relentless – It is a relatively weak force, but never stops. 
3. Star formation is a relatively recent phenomenon (on the Cosmological time scale), and the rate of formation has slowed down.

In the discussion, Dr. Holder walked us through the currently most-accepted view that the universe started off as a hot singularity, expanded rapidly at the Big Bang, and has continued to expand ever since.

He informed us that shortly after the Big Bang, the universe was quite smooth, but got more “lumpy” as gravity slowly took over – forming atom parts, then atoms themselves, and then progressively larger structures, including stars and galaxies.