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If this writing is blue you're going too fast!

This is what happens when particle physicists start getting into astronomy. They are certainly right that the potential to use quark stars to study quarks is very interesting, but they seemed to have overlooked the most important step of all-- the actual observation of quark stars. Theorists certainly hit a home run with black holes, but I don't think we can put quark stars into that category just yet. We'll need a little more evidence that they actually exist before we can tout them as fundamental particle laboratories-- a few radio-quiet neutron stars is not going to cut it. Also, the authors are a bit misleading when they suggest that we can't explain gamma ray bursts so we need quark stars. In fact, progress in explaining gamma ray bursts without quark stars has made great strides in recent years, so either the quoted author, or the reporter, is being a bit dishonest in the effort to sell the idea. Scientists should not try to hawk theories, they should try to challenge and falsify theories in a classic example of survival of the fittest.

There's more evidence to quark stars than just what is in that article Ken. The two best candidates include one(RX J185635-375) that is much dimmer than it should be based on neutron star theory. If the star is smaller than a neutron star, (and it has been measured (based on temprature and luminosity) by Chandra to be only 11 km in diameter, smaller than neutron star theory allows) the visible light matches what is observed. Another star (3C58) is much cooler than expected, based on the the theoretical cooldown of a neutron star. Both the above can be modeled using a strange quark star. For some reason, my Adobe is acting up and I can’t give you links to papers, but if you do a google search on each of those designators, you will find several paper on each.

Now, I'm not saying that this is absolute evidence for quark stars. In the case of the smaller one(RX J185635-375), some critics have claimed a hot spot was measured, and the star is cooler overall. This could possibly be the reason the star is not as bright, instead of it being too small. I just wanted to point out that there are other theoretical reasons for suspecting quark stars. And the quark star models seem to agree with the observations on the two stars.

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Some try to tell me, thoughts they cannot defend,... - Moody Blues.

That is interesting information Tensor. I may be too quick to judge, if quark stars are the next black holes then I will certainly eat my words. But I smell, if not a rat, perhaps a hamster.

From your post, it seemed you weren't aware of the those observations. You usually aren't so dismissive.

Actually, when I first studied the EOS for white dwarfs and neutron stars, I wondered why, or even if, there was an equivalent degeneracy pressure for quarks. I didn't know the QM equations then (and am not that much further along now), so I still don't know why. Not to mention, it doesn't appear that "quark degneracy pressure" has anything to do with this anyhow.

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Some try to tell me, thoughts they cannot defend,... - Moody Blues.

I don't mean to be dismissive, only skeptical. But I certainly should not have maligned the researchers for overextending particle physics into astronomy-- the synergy of those fields is important and quite valuable. It would be very exciting if quark stars really existed, and if the equations suggest it is possible, then I am glad some people are seriously pursuing the possibility. They should get the Nobel prize if they are right. There was just a flavor of salesmanship in the quoted link that I think is detrimental to science-- when people want something to be true too much, it can really color the quality of their scientific conclusions. Citing gamma ray bursts as evidence for quark stars really struck me as disingenuous, for example. But it doesn't make it wrong...

We didn't have much proof of black holes until recently. Even then we would not have known to look had they not been theorized. It may be very early to say that they do or don't exist, however if the math supports them, we should be cautious to dismiss it as an unprovable theory. Perhaps we simply haven't figured out how to look for them yet.

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From the land of the free because of the brave!

I don't dismiss quark stars, I object to the environment of twisting information to try to convince people of their existence while the evidence is still quite flimsy. Why can't the authors just say "if these turn out to be real, they will be very useful to understand", rather than "So the universe has provided us with a natural laboratory to study their properties." (quoted from the above link.) If that latter statement was made about ghosts or UFOs, we'd call it pseudoscience. That quark stars have current theoretical support, while ghosts and UFOs don't, is not good enough.