Slashdot Mirror
NASA and DoE Team On Dark Energy Research
Roland Piquepaille writes "NASA and the U.S. Department of Energy have teamed up to operate the future Joint Dark Energy Mission. As you probably know, recent astronomical measurements have showed that about 72% of the total energy in the universe is dark energy, even if scientists don't know much about it, but speculate that it is present almost since the beginning of our Universe more than 13 billion years ago. The JDEM 'mission will make precise measurements of the expansion rate of the universe to understand how this rate has changed with time. These measurements will yield vital clues about the nature of dark energy.' The launch of a spacecraft for the JDEM mission is not planned before 2015."
Come on.... "Dark Energy" this should have everyone wearing some form of mask and a black uniform with just a simple white spark on it or something. We complain about not getting kids into science and then when we get something with one of the coolest sounding names around we make it into something dull and boring.
"Dark Energy has been around for 13 billion years but no-one has been able to harness it. Do you have what it takes to join the Legion of Dark Scientists?"
An Eye for an Eye will make the whole world blind - Gandhi
And even if Dark Matter/Dark Energy really does not exist, I think it's justifiable that people search for it. If the experiments don't match what the scientists say about it, we'll know we need another explanation. The money will not be spent in vain.
Any life is made up of a single moment, the moment in which a man finds out, once and for all, who he is.
My problem with both theories is that they seem to be band-aids applied to current physics to tweak the result to something that matches our observations. For example, we assume that general relativity works the same for superclusters of galaxies as it does here in our solar system. Problem is the results it gives don't match our observations. So is this evidence that the theory breaks down over very large scales? Nope, it just means the universe is mostly made of invisible energy with negative pressure that only interacts through gravitation.
The whole situation reminds me of the aether theories of early physics. The problem then was that Newton's explanation of light provided a very good explanation for reflection, but not refraction or diffraction. The assumption was that since the theory worked well on one set of problems, it must work equally well on another similar set. It didn't, but no matter. By assuming light travels through a medium, the aether, you could tweak the equations to give results close to the observations.
Over the next 200 years this aether gained more and more 'magical' properties to tweak the results of other theories. It had to be a fluid, but also millions of times more rigid than steel. It had to be massless, completely transparent, incompressible and a whole host of other things all at the same time. Everyone was aware of the obvious problems here, but because so many physical theories (theories that gave pretty accurate predictions) were based on it it was just assumed to exist.
In the end aether theory was made obsolete when Einstein re-wrote the incomplete physics that relied on it to deliver accurate predictions. Physics was stuck in a rut for 200 years because it assumed aether must exist, and everyone's efforts were aimed at incorporating aether into physical theories. I just hope this isn't happening again with Dark Matter/Energy.
Disclaimer: I am not a physicist or cosmologist, I just have a passing interest in this stuff, so take what I've said as nothing more than an opinion.
Murphey's fighting Occam, and we're in the stands.
The idea of a luminiferous aether followed naturally from the observation that light acted like a wave, and one of the fundamental things about waves is that they travelled in a medium.
This lead to experiments designed to detect the medium of light (like the famous Michelson-Morley one), to the Lorentz transformations and the Theory of Relativity. The aether conjecture is science at its best: hypothesis, experiment, falsification, paradigm shift. Why it's used as a metaphor for stupidity has always been a mystery to me.
Does this temper your skepticism any?
I find it hard to accept the idea that some lone guy on slashdot has found a problem in the maths used by all the astronomers in the world who describe galaxy rotation, or indeed that even if you had, it seems galaxy rotation is not the sole piece of evidence for dark matter.
(1.21 gigawatts) / (88 miles per hour) = 30 757 874 newtons