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Dark Matter Stars in the Early Universe?
OriginalArlen writes "UniverseToday reports new research which suggests dark matter could have condensed to form 'dark stars' in the early universe. These stars would have been very massive and burned very slowly, fueled by non-fusion reactions, they could still be with us. Astronomers hope to better constrain theories of early galaxy and star formation with observations of gravitational lensing events caused by these ghosts of the primordial universe."
Here is the PDF: Dark matter and the first stars: a new phase of stellar evolution
Here is the abstract:
Note that dark matter is *not* regular matter. It is matter which does not interact through the electro-magnetic forces. It does not interact "with charged particles" nor with light! Hence, the name "dark." If light can not scatter from it, then that makes it "dark."
An Arxiv paper doesn't really "count" as a publication for most purposes and certainly will not prevent you from "perishing" (that's what the peer-reviewed scientific journals are for).
Publishing in Arxiv is more like posting to a blog or slashdot where you semi-formally share your ideas and try to start up a discussion on the topic of interest to you.
Of course, some of the papers over there ended up being darn important.
Obama likes poor people so much, he wants to make more of them.
The idea that the net sum product of the Big Bang is 0 (zero) mass and energy is old, and has been discarded for better theories.
Except that's not exactly right. Matter and antimatter annihilate, true, but they produce energy as the product of that annihilation. So it's not exactly a zero-sum-game as you seem to think. You may be getting confused by vacuum flux (a real phenomenon that has been experimentally observed), in which pairs of virtual particles and anti-particles are spontaneously created in a vacuum, only to disappear without a trace when they collide again. In that case, you end up with nothing (unless you're talking about a region of space arbitrarily close to the event horizon of a black hole -- that's how Hawking radiation works).
Try "never." The current standard model in cosmology posits that matter and antimatter were created in nearly equal quantities which condensed out of the energy of the Big Bang. The resultant mass reacted with itself, and the energy produced by these annihilations generated the next wave of particle creation. Eventually, a very slight bias in the production of matter vs. antimatter led to the overwhelming dominance of "normal" baryonic matter in the visible universe.
The idea that there are vast pockets of antimatter out there in the universe has been generally discarded. As for why there was a bias toward "normal" matter and against antimatter, I don't think that has ever been adequately explained, although there are several competing theories. It's interesting to note that in quantum mechanics, you can model antimatter interactions as a sort of time-reversal of matter interactions -- leading to the bizarre notion that antimatter is just normal matter that's "backwards" in time. Perhaps entropy provided enough of a "time arrow" to force a bias in the early universe's composition. (Or, as I sometimes muse, there might be some as-yet-unknown force that is responsible for breaking symmetry in time, and entropy as we understand it is just a product of this force.)
The "antimatter is just matter backwards in time" concept was kind of a shocker to me, taking quantum mechanics classes as a college undergrad. I'd been introduced to the concept by a story or novella that was published in Analog, and had dismissed the idea as hokey... and then one day, I cracked open one of my textbooks and saw a weird little diagram, and asked why there was an electron moving backwards in the time dimension, to which the professor responded, "That's a positron."
See Clowe, Douglas et al (2006). "A Direct Empirical Proof of the Existence of Dark Matter," The Astrophysical Journal, ISSN 0004-637X, 648 (September 10): L109-L113.
It was big news at the time so Google will find you plenty of commentary online.
My own instincts suggest that we will eventually come to realise that dark matter and "dark energy" are as close as we will ever get to the main game in town and that baryonic matter will come to be seen as just the scum on the pond.
-- Our systemic servants do not good masters make.
>> Gravity doesn't obey Newton's laws on the very small scale (atomic)...
>
>What gives you that idea?
Quantum Gravity
"the first quantum-mechanical corrections to graviton-graviton scattering and Newton's law of gravitation have been explicitly computed (although they are so astronomically small that we may never be able to measure them)"
Look at the bottom of this link. Dark matter and antimatter are two separate issues. Antimatter was verified with the observation of the positron that you mention in the 1930's and the existence of antimatter hasn't really been debated since then. Dark matter is something totally different... it's existence is suggested by astrophysical data and not by experimental particle physics. There is no theoretical understanding of dark matter. It's all suggested by observation. Of course, that's the way science is supposed to work, but in a few cases theoretical understanding preceded observation, as was the case with antimatter.