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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
Once they form the Department of Dark Energy they could post job ads reading "Come to the dark side".
if there's so much dark energy in the universe, then why don't we have any local in our own little solar system or planet? how come dark energy only makes the science of things far away off-kilter, yet all our science locally we can measure to 9 or more decimal places? seems like an awfully big fudge factor, if you ask me.
Actually DOE has always been deeply involved in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.
You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).
Of course being a couch-scientist (worse than amateur scientist), I might be hugely wrong, but somehow, I don't think I am (surprisingly).
Unfortunately, you are wrong, and I guess it's not that surprising, considering your ... interesting take on cosmology. Einstein's work was intimately concerned with the nature of spacetime, so saying that "he looked soley[sic] at matter" is flat-out wrong.
Space and matter are the same? Then either space has a gravitational effect, or they're the "same" in a way that doesn't include a fundamental property of matter, which is to say that they're not the same at all (you'll recognise the quote "in exactly the same way that bricks don't" -- it speaks to nature of classification rather elegantly I think).
So why hasn't the gravitational effect of space been detected? Oh, wait, because the scientists missed something. Silly scientists!
I was always a skeptic when it came to Dark Matter(I am not an astronomer, so this all technically an uniformed opinion). But now I know that it really is all a load of idle speculation coupled with incomplete investigation, and an excessive dose of hype. It only took a few minutes of googling to come up with this paper.
One of the biggest pieces of evidence for Dark Matter is the Galaxy Rotation Problem. Basically the rotations of Galaxies do not behave as astronomers expect them to do, leading to the hypothesis that there is more matter in them that we cannot see, "Dark Matter". The velocity profiles that Astronomers expect to see are Keplerian. That is, they expect star systems in galaxies to behave like planets in solar systems when it comes to orbit speed and distance from the focus of rotation.
The bottom line is, as shown in the paper, this assumption is totally unjustified. The integrals in the 2D galactic disc case do not work out using Shell Theorem, which cannot be applied. They are instead quite nasty singular integrals, but twenty minutes with MATLAB and the "QUAD" function will be all it takes to see that basic gravitational theory most certainly does not predict that Galaxies should have Keplerian(Solar System-like) rotation curves, and there is no reason whatsoever for astronomers to assume this. It's all basic mathematical physics well withing the reach of many reading this post.
The galactic rotation problem is not evidence for Dark Matter. It is only evidence of the need for more applied mathematics courses in astronomy undergraduate degrees. Of course the Galactic rotation problem is not the only evidence for Dark Matter, but it is a big part. The other big piece of evidence was the Galactic Cluster mass problem. It's been a while since I read the relevant papers, but as I recall, Zwicky played hard and fast with the virial theorem, in particular making assumptions about the stability of Galactic clusters.
Again of course, I am not an astronomer. I am essentially a lay person in these matters, so my posts and opinions (not only in this thread) should be taken with a pinch of salt. Still, I stand by my overall skepticism of Dark Matter theories, and I stand quite firmly on my objections to the interpretation of the Galactic rotation problem. I expect that in the near future, as our ability to analyse and simulate galatic dynamics improves, Dark Matter will finally be debunked.
May the Maths Be with you!
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.
Except, I don't really see how high energy physics is involved. I mean, it's not as if anybody has proposed a high-energy experiment that could detect it.
Ultimately, there must be a particle-physics-based explanation for Dark Energy, whether from string theory or something other theory.
And just because Dark Energy not accessible via "classical" accelerator experiments, this does not mean that it should not be considered experimental particle physics research. In other words, instead of using a ground-based accelerator, the Universe is the "poor man's" accelerator.
If NASA and the DoE start yanking on the Dark Energy in the Universe, they might find that attached to the other end are . . . Dark Energy Creatures.
They might not be amused with the antics of NASA and the DoE.
"Hey, you, Earthling! Is this your Joint Dark Mission Probe, that just broke my window?"
You have been warned.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Actually DOE has always been deeply involved in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.
Good so far.
You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).
Yes, but don't forget that DOE has its own cosmologists, too. The DOE end of JDEM is being handled by Lawrence Berkeley National Laboratory, which has quite a bit of stuff going on in cosmology, mostly under its physics division.
(I do some work with one of the collaborations based there.)
Village idiot in some extremely smart villages.
Once scientists understand that space and matter is the same thing (something you should be able to test and prove here on earth) they should understand that dark matter is just space.
Although attempts have been made to unify matter and space (see Wheeler's geon idea), they've all failed. Matter and space appear to be different. But even if they were unified, so what? What's the practical difference between "matter which is secretly some aspect of space" and "matter"? I mean, I can say that an electron is really just "space", but that doesn't prevent it from acting like matter.
it's really interesting that they aren't doing it with a clear understanding about what they're measuring or why.
They have quite concrete ideas of what they're measuring. They just don't happen to agree with your pet ideas of what they're "really" measuring.
Space can have a gravitational effect: in general relativity, gravity gravitates. A black hole is a vacuum solution of the Einstein field equations. And if you object to it being vacuum because you can't say what's at the singularity, there are non-singular vacuum solutions too, like gravitational geons. However, they're not stable, so attempts to describe matter as pure space have failed. (Another attempt which also largely failed is to describe particles as wormhole mouths.)
Some people think that dark energy is the gravitational effect of space. See the vacuum energy interpretation of the cosmological constant. That is also different, however, from dark energy being matter, or matter being space.
Matter = space is an intriguing idea, but people have worked on it for over 50 years and haven't made it work. Maybe with a full theory of quantum gravity they could, but I really doubt that would lend any new insight into dark matter or energy, any more than it would suddenly revolutionize our understanding of electrons — the relevant physics would have to be Planck scale and mostly irrelevant except maybe at the Big Bang.
Lindsay: Yes. For example, no one was showing up for jury
duty, so we made the experience more exciting by
synergizing it with his comic book collection.
[cut to Moe's tavern. Moe opens an envelope]
Moe: [reading] You have been chosen to join the Justice
Squadron, 8 a.m. Monday at the Municipal Fortress of
Vengeance. Oh, I am *so* there!