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From: http://casa.colorado.edu/~ajsh/hawk.html in part reads: "Evaporation of a mini black hole Black holes get the energy to radiate Hawking radiation from their rest mass energy. So if a black hole is not accreting mass from outside, it will lose mass by Hawking radiation, and will eventually...

Yes; the equation would be: "Minimum Mass = No Black Hole Anymore = (Mass=0)"...:biggrin:

True, and the smaller the BH, the more intense the Hawking radiation. Regarding small BH's, someone coined the (now) common phrase: "Black holes are white hot." Also there are two opinions on the "finality" of small BH's; one is "evaporation" you mention above and the other is that once a...

The Event Horizon (EH) calculates to spherical, but all Black Holes (BH) rotate; none can be "non-rotating". That was shown long ago. Actually, Hawking Radiation (HR) "comes from" the edge of the EH which is the classical 2GM/c2. This EH is at the same radius for a rotating BH as it is in the...

From Post 2: What else can I say? Other people refer to "zero-point" something(?) but I'm saying no such thing. No reply is needed, PLEASE!

You didn't get my meaning. I will never "accept the conclusion of infinite density" OR accept any assumption of zero volume. I never called any "volume" zero; it is exactly that which I have been posting about.(Against?) I think that we generally agree but have a "semantics" problem going on...

:uhh: But, my point is that there is nothing with zero volumn! If zero-volumn is considered, then whatever it may be called just doesn't exist. This is "General Astronomy" so go to some other more advanced forums, or many recent (last 5 years) papers published by "well-known" astrophysicists and...

Take any sized finite volumn you can think of; maybe a sphere with a diameter of 1 Planck length, or a basketball. How can you fill that volumn to infinite density without using an infinite amount of mass? I can't think of a way to accomplish that.(?) That's how it implies infinite mass. p=m/V.

Agreed, but what I meant to explain is that a "signularity" as defined 10-15 years ago doesn't exist. The "center" of a BH has a finite size with a very large density but not an infinite density. The gravity of the large mass still exists and the measure of the mass determines the EH boundry...

To any "outside observer", time appears to stop at the Event Horizon (EH) which is an "effect" at: 2Gm/c^2 or at the poles (only) of an "Ergosphere" where the gravity curves space-time back into a "loop" returning to the interior of the EH boundry. (That is definitely a non-technical...

I'm not sure what you mean by "pole" but most recent accepted theory is that the "center" of a black hole is not a zero-point singularity. The "center" must have a finite size of at least a Planck length: (1.61624 × 10-35 m). Infinities simply do not work in math, and a zero-size point of any...

The term "necro" simply means dead.

Try these: http://www.peripatus.gen.nz/Astronomy/CepVar.html [Broken] http://sims.berkeley.edu/~jhall/ho/ http://www.fofweb.com/Subscription/Science/Helicon.asp?SID=2&iPin=ffdastron2630 http://www.madsci.org/posts/archives/2004-02/1076556627.As.r.html...

There is no "dark side of the moon". All of it is in sunlight once every lunation, just as Earth has no dark side.

This only goes back to 1885, but it is a LONG list. http://cfa-www.harvard.edu/iau/lists/Supernovae.html

http://news.yahoo.com/s/nm/20061206/sc_nm/blackhole_dc [Broken] If this were the case as explained, wouldn't we be detecting in X-ray also?

Are you still refusing to pay attention to post #8 above? Too lazy to read a bit? As someone once said:

That's just not how it works, but trust me, there have been PLENTY of PF threads on the subject. All you need is to find a few and read for hours. P.S. Electrons or any particle with mass will never accelerate to c.

Re-read post #8 above and then go to the link(s) provided. That explains it about as well as any you'll find.

I have posted this before but it fits well here too.

Sorry, but I have to let my last post above stand as final opinion on this subject. I just can't imagine how all those astrophysicists wasted their education and years of research when all they needed was an EE degree to solve all of the current mysteries of the cosmos. As for my ignorance...

Hilton; The first link didn't open an accesible page. The second link connected to long essays which seemed to use tons of verbage but no reasonable "back-up" for any of the "claims-of-truth". A few quotes from that page and its links were: I have added the underlines and emphasis...

Do you have the reference, ..please ??..:confused: ..:confused:

I would like the reference on that one, please. It could let me understand what type of object could rotate 716 times per second. http://www.nrao.edu/pr/2006/mspulsar/

I agree with that 100% and have never "bought" the idea of a zero size or infinite density for a so-called singularity. I think the Planck length or Planck density would be a minimum for any amount of collapsed matter, but actually think that any "singularity" would be even larger than that...

Ok, but Marcus said it would change to a more elliptical orbit and you give the formulae for a circular, closer orbit. Wouldn't it do a more eccentric ellipse like Marcus posted? And, would it ever return to the aphelion radius we now have?? Every time I post anything re: solar...

The Sun would still be considered a "massive body", especially relative to the Earth's mass. Therefore, reducing the orbital velocity of the Earth would make that velocity less than necessary to maintain orbit at present or lesser distance so the Earth would slowly spiral inward and eventually...

That was already answered this week https://www.physicsforums.com/showthread.php?p=1145337#post1145337".

Matter from a BH is not coming out of the event horizon (EH). There are two methods where matter can radiate from a BH, and Hawking Radiation is the most well-known. In this case, any escaping matter is created just outside the EH and sometimes, one of two virtual particles can escape while the...

I haven't heard of "conservation of mass", only conservation of energy. But, since mass = energy (e=mc2) I guess it could be called either.(?) A BH can form from several methods; direct collapse of a massive star, large core remaining from a Type II supernova, merger of two massive bodies...

Pick a distance, any distance from a ball, rotating or not. If within the ball (sphere) the net gravity is zero, beyond the ball it would be the Schwartzchild coordinates. That gives the "spherical symmetry" of the gravitational field. Only some cataclysmic event, as explained by many other...

Yes, spherical symmetry, BUT, of the gravitational field at a distance. It is not about the shape (spherical or oblate) of the object itself.

Some should be listed http://www.astro.uiuc.edu/~kaler/sow/class.html#variable" [Broken], or various links from the top of the page.

Which is also a problem with any telescope where a secondary mirror is held by "spider vanes" crossing the field of incoming light to the main objective. Even a secondary without vanes, as in an SCT or Maksutov, causes diffraction from the edges of the secondary simply because it (the secondary)...

I would have to guess that a quick perusal of the SOHO and NOAA websites would give you several ideas to ponder.

Thanks ST; at least I was mostly right in my earlier posts. Especially when I posted in # 12: When the Sun contains more than 99.8% of the total mass of the Solar System, is seems that two orbiting (asteroids, for instance) would have a whole lot more pertubations acting on them from other...

Yes, but slowly, not instantly..:eek:

That's about all I really meant.

Not squished necessarily, but total disaster. As of now, the Earth is "compressed" by tidal forces between Sun and Moon in a vectored direction. If the Sun's gravity were to "let go" 499 seconds (mean) after the Sun disappeared, the tidal forces would be instantly gone and the Earth's crust...

I didn't look at the whole thing yet, but it should be on: http://chjaa.bao.ac.cn/2004/2004_4_5p490.pdf (Pages 2 & 3) or at: http://www.journals.uchicago.edu/ApJ/journal/issues/ApJS/v108n2/33389/33389.web.pdf [Broken] (Page 6).

In looking at the formulae for two-body systems, it appears that you are right and Labguy blew it, so I was likely wrong...:frown: But, that's Ok, I think I was wrong once before a long time ago on simple, stupid stuff...:biggrin: I hate and "don't do" planetary and solar system stuff. Why...

These may not be technical enough, but try http://arxiv.org/PS_cache/astro-ph/pdf/0401/0401088.pdf" [Broken].

So, are you saying that two asteroids at the same distance from the sun revolve with different periods because one is massive and one is a small rock? Are you saying that the Space Shuttle and the ISS (not docked) revolve with different periods because one has more mass? Does a golf ball...

Yes, but consider two objects at any distance from the "main" body, like jupiter's moons or your example above. If you have a massive planet (or moon or small rock) orbiting at the same distance, their period will be the same. The small one won't go faster than the big one just because it has a...

Try putting an F-18 down on a rolling Carrier...:biggrin:

Which is exactly what became several L-O-N-G threads on the General Astronomy forum. Check over there for about all the opinions and questions you would ever want to read...:smile:

You didn't specify anything about a supernova, just electron degeracy. For that see http://imagine.gsfc.nasa.gov/docs/science/know_l2/dwarfs.html".

Your milk bottle is a lens, badly formed, that is causing both refraction and diffraction problems (effects) to the light. You have chromatic aberration problems and diffraction problems in focusing to the "most visable" light, causing yellow to be, as in most short focal length lenses, the...

Drift alignment is usually reserved for scopes on a permanent mounting. It takes a long time to get it right. I once did it on a 16", f/ Newtonian on a 2000 pound mount. With one helper, it took two nights but then stayed dead-on for two years. Seeing drift in the eyepiece has nothing to do...

I can guarantee you that was, and would always be, your biggest alignment problem. Another point: did you loosen both the RA and DEC axis (one at a time) and move the scope & counterweight for a near-perfect balance?