Cosmology





Dark Energy & Dark Matter

We're learning at a fast clip that we don't know as much as we thought we did. But, maybe the LHC will catch us up next week.

By: Ernie Fitzpatrick
For those that have the fancy calculators or whatever measuring devices that they have, say that about four percent of the universe is capable of being directly probed by our "current scientific instruments". Wo what's that mean? It says that scientists now believe that 96% of the universe is amde up of dark energy (73%) and dark matter (23%). So let's take a look at the implications of such theory or postulates. 

The discovery in 1998 that the universe is actually speeding up its expansion was a shock to traditional astronomers. But, the evidence has become convincing.

In physical cosmology, dark energy is an exotic form of energy that permeates all of space and tends to increase the rate of expansion of the universe. Dark energy is the most popular way to explain recent observations that the universe appears to be expanding at an accelerating rate. In the standard model of cosmology, dark energy currently accounts for 73% of the total mass-energy of the universe. What's standard any more?   :-)

Dark matter is hypothetical matter that does not interact with the electromagnetic force, but whose presence can be inferred from gravitational effects on visible matter. According to present observations of structures larger than galaxies, as well as Big Bang cosmology, dark matter accounts for the vast majority of mass in the observable universe.

Is there an English version of the above?  :-)

Dark energy, a mysterious force that no one understands, is causing the universe to fly apart faster and faster. Only a few years ago, if you'd suggested something like that to astronomers, they would have told you not not change your day job, unless it was cosmology or physics. But dark energy is real or at least, a growing number of astronomers think it is. No one, however, can truly explain it. So, are we saying we beleive in something we don't know?

Sorta!

Dark energy entered the astronomical scene in 1998, after two groups of astronomers made a survey of exploding stars, or supernovas, in a number of distant galaxies. These researchers found that the supernovas were dimmer than they should have been, and that meant they were farther away than they should have been. The only way for that to happen, the astronomers realized, was if the expansion of the universe had sped up at some time in the past.

"Frankly, we just dont understand it," says Craig Hogan, an astronomer at the University of Washington at Seattle. "We know what its effects are," Hogan says, but as to the details of dark energy, "Were completely clueless about that. And everybodys clueless about it."

Maybe we'll know something this coming week as they throw the switch on the Large Hadrom Collider (LHC). CLues to 2012 just might be found in CERN. Stay tuned and keep the tin foil on your head til then.   :-)

As a spiritual-futurist, I interpret current events in light of possible macro-universal forces at play leading up to 2012, but not limited to it.









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