Talk:Exotic star

Page history

The Yeti (talk · contribs) has messed up this page's history. Instead of reverting to the pre-redirect version, s/he copy-pasted existing articles here without attribution. See http://en.wikipedia.org/enwiki/w/index.php?title=Exotic_star&action=historysubmit&diff=381918363&oldid=310531196 and the pages than were copy-pasted here without summary or talk page attribution. 76.66.203.138 (talk) 11:36, 30 October 2010 (UTC)

I'm adding the tag templates here for attribution purposes necessary for users of this page to figure out where things are from, since it's not in the edit summaries. 76.66.203.138 (talk) 11:45, 30 October 2010 (UTC)

On second thought, this is even more messed up; Charvest (talk · contribs) did the same thing last year! 76.66.203.138 (talk) 12:02, 30 October 2010 (UTC)

Earth comparison

Hi, the article Earth states that Earth is around 5.9*10^24 kilos. If preon matter is 10^23 per m^3, I don't see how a tennis ball worth of it is the same mass as Earth. Works out to be around 59 cubic meters of the stuff or around a large trash container, unless this lurker is missing something. 96.55.136.38 (talk) 10:40, 8 May 2011 (UTC)

Maybe a tennis ball 2.415 m in radius? Rich Farmbrough, 10:27, 6 September 2011 (UTC).

Q stars removed?

I added way back the AJ papers about a theoritical Q stars (aka. Gray Holes). Now that has been removed. I do not know if the theory has been debunked or just least favored. So should Q stars be added back or not? Thanks, Marasama (talk) 15:58, 28 December 2011 (UTC)

They should be added back, since it still exists as compact star, it should exist here. The Q star article has even been revived. -- 65.92.180.137 (talk) 06:12, 14 March 2013 (UTC)

Ultra relativistic pressure could support a Compact Star

All the contents of a light containing compact star would be expected to be ultra relativistic. If the pressure P of ultra relativistic material is given as (rho)(c^2)/3 [where rho is the energy density], the total supporting energy or viral energy of this star would be ∫PdV = (Mc^2)/3, meaning a whopping 1/3 of the mass energy of the star would be used just to oppose the force of gravity. The Newtonian gravitational binding energy of a gas star is considered to be about G(M^2)/R . I do not know the formula for the gravitational binding energy of an ultra relativistic star - does someone know this or how to calculate this? Is the Newtonian ratio of viral energy to binding energy the same for ultra relativistic material? From my limited understanding of relativistic gravity it appears that the gravitational binding energy of an ultra relativistic star could be twice the newtonian value, or 2G(M^2)/R . Using the viral equation, if (Mc^2)/3 is equal to 1/2 the gravitational binding energy, or G(M^2)/R, the radius R of this star equals 3GM/(c^2), or 1.5 times the Schwarzchild radius. I do not know if this figure of 1.5 times the Schwarzchild radius is correct, maybe these calculations have a cancelation of errors. But note if a star of about 1.5 - 2 times the Schwarzchild radius exists it would still contain light but not as well as a singularity of the same mass; it would contain light up to a little less than 2 to 3 times the Schwarzchild radius. There is observational evidence that this type of star is contained in a black hole: (1) Some black holes eject more energy than would be expected. (2) Some super massive black holes have been observed spinning at about 1/10 RPM, which implies a star of very large radius. The existance of an about 1.5 - 2 Schwarzchild radius star, instead of a conventional black hole point singularity, would probably mean the end of the conventional big bang model as coming from a point singularity. If 2 approximately equal mass 1.5 - 2 Schwarzchild radius stars merged the contents would be expected to be ejected at the speed of light from the contact point. This model could explain where our inflationary universe came from. It could also explain a possible ancient explosion at the center of M87. 172.162.25.192 (talk) 15:52, 11 May 2014 (UTC)BG

planck star removed

carlo rovelli wrote about planck stars sustained by quantum gravitational pressure — Preceding unsigned comment added by 24.94.181.85 (talk • contribs) 18:46, 11 January 2015 (UTC)

Are quark stars black holes?

If quark material should be the limit to compression of matter and energy, then such is the limit to degeneracy. Condensed quark matter (which might have incorporated photons that have fallen into the quark star and never having a chance to escape) could then be dense enough to create a black hole if in an adequate mass. If further compression beyond quarks is impossible, then a black hole might still have some semblance of a rigid structure while having an event horizon. Of course a stellar-mass quark star/black hole would absorb in-falling matter and radiation and incorporate such matter and radiation into the quark star as quark matter (and captured photons, whatever those become).

This speculation, should it hold true, would prevent the absurdity of division by zero of infinite density at an infinitesimal point. The gravitation and matter remain. Of course, black holes can offer no indication of anything other than mass, charge, and rotation. It is unlikely, of course, that any quark star could ever be seen. Pbrower2a (talk) 15:14, 29 February 2016 (UTC)

If the degeneracy pressure involved does not prevent the star from shrinking below the event horizon, then it should create some form of black hole, but not the traditional singularity based one. The section on Planck stars suggests such a star as well. -- 65.94.171.217 (talk) 12:39, 3 November 2016 (UTC)