Titanomachy
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From: Dennis M. Hammes on 30 Nov 2007 03:14 Ned wrote: > "Don Shepherd" <donshep2.nospam(a)verizon.net> wrote in message > news:QaE3j.15559$Mr.695(a)trnddc04... > >>>But seriously, how fast would a singularity have to spin >>>in order for it to fly apart? >>>Ned >> >>0/0 rpm. >>Don >> > > > Ok, how fast would the earth have to spin for you to fly > off it (assuming you were on the equator)? What is the > escape velocity on earth - 25,000 miles per hour? So a > person on the equator moves through one circumference, > which is about 25,000 miles, in 24 hours, or about 1000 > miles per hour. So if we speeded up the earth to 25,000 > mph, or about 25 times its current rotational speed, or > about one rotation per hour, things would fly off the > equator. (Including dirt and mountains, etc. - of course, > most organic matter would burn up.) > > Hmmm... that's interesting - wiki is quite adamant that > the escape velocity of a black hole is infinite. That seems > intuitively irritating. Ah, no wonder. The escape velocity of a Black Hole is /not/ infinite, it is merely greater than /c/ at r sub S (which defines r sub S, the Schwartzschild Radius). For the escape velocity to be infinite, /g/ would have to be infinite, and the whole dam' universe would be in there already. Since it isn't, it isn't. > > That's saying that no matter how fast a black hole spins, > it CAN'T break up?? No way! There has GOT to be some > rotational speed at which all the mass in a black hole > becomes unstable and begins to break up. No, stop! Don't > lecture me. Pick a number, a huge - impossibly huge - > number, say 500 billion trillion revolutions per second. > Don't tell me nothing bad would happen to the back hole > under the force of that much angular momentum! > > Ned > The "mass" in a Black Hole is already as degenerate as a Newsfroup, which is why a Newsfroup swallows everything you throw at it no matter how fast it's running in circles. -- -------(m+ ~/:o)_| Gresham's Law is not worth a Continental. http://scrawlmark.org
From: Dennis M. Hammes on 30 Nov 2007 03:28 Rik wrote: > Ned wrote: > >> "Don Shepherd" <donshep2.nospam(a)verizon.net> wrote in message >> news:QaE3j.15559$Mr.695(a)trnddc04... >> >>>> But seriously, how fast would a singularity have to spin >>>> in order for it to fly apart? >>>> Ned >>> >>> 0/0 rpm. >>> Don >>> >> >> Ok, how fast would the earth have to spin for you to fly >> off it (assuming you were on the equator)? What is the >> escape velocity on earth - 25,000 miles per hour? So a >> person on the equator moves through one circumference, >> which is about 25,000 miles, in 24 hours, or about 1000 >> miles per hour. So if we speeded up the earth to 25,000 >> mph, or about 25 times its current rotational speed, or >> about one rotation per hour, things would fly off the >> equator. (Including dirt and mountains, etc. - of course, >> most organic matter would burn up.) >> >> Hmmm... that's interesting - wiki is quite adamant that >> the escape velocity of a black hole is infinite. That seems >> intuitively irritating. >> > Surely it just needs to be slightly higher than the speed of light. > Which is in turn slightly lower than the speed achieved by the average > poet chasing a publishing contract. > > Rik, knee deep. Perzackly. If v sub esc were infinite, r sub S (the Schwarzschild Radius) would be infinite, or at least the radius of the universe, i.e., the whole universe would already be in there. Since it isn't, it isn't. I.e., it isn't over until the fat lady singes. > >> That's saying that no matter how fast a black hole spins, >> it CAN'T break up?? No way! There has GOT to be some >> rotational speed at which all the mass in a black hole >> becomes unstable and begins to break up. No, stop! Don't >> lecture me. Pick a number, a huge - impossibly huge - >> number, say 500 billion trillion revolutions per second. >> Don't tell me nothing bad would happen to the back hole >> under the force of that much angular momentum! >> >> Ned >> >> -- -------(m+ ~/:o)_| Gresham's Law is not worth a Continental. http://scrawlmark.org
From: Ned on 30 Nov 2007 10:52 "Dennis M. Hammes" <scrawlmark(a)arvig.net> wrote in message news:FvqdnXiTQpsOVNLanZ2dnUVZ_hWdnZ2d(a)onvoy.com... > >>> Ok, how fast would the earth have to spin for you to fly >>> off it (assuming you were on the equator)? What is the >>> escape velocity on earth - 25,000 miles per hour? So a >>> person on the equator moves through one circumference, >>> which is about 25,000 miles, in 24 hours, or about 1000 >>> miles per hour. So if we speeded up the earth to 25,000 >>> mph, or about 25 times its current rotational speed, or >>> about one rotation per hour, things would fly off the >>> equator. (Including dirt and mountains, etc. - of course, >>> most organic matter would burn up.) >>> Hmmm... that's interesting - wiki is quite adamant that >>> the escape velocity of a black hole is infinite. That seems >>> intuitively irritating. >>> >> Surely it just needs to be slightly higher than the speed of >> light. Which is in turn slightly lower than the speed achieved >> by the average poet chasing a publishing contract. >> Rik, knee deep. > > Perzackly. > If v sub esc were infinite, r sub S (the Schwarzschild Radius) > would be infinite, or at least the radius of the universe, i.e., > the whole universe would already be in there. > Since it isn't, it isn't. > I.e., it isn't over until the fat lady singes. > How do you know the whole universe isn't in there? Ned
From: Keynes on 30 Nov 2007 11:19 On Fri, 30 Nov 2007 02:14:16 -0600, "Dennis M. Hammes" <scrawlmark(a)arvig.net> wrote: >Ned wrote: > >> "Don Shepherd" <donshep2.nospam(a)verizon.net> wrote in message >> news:QaE3j.15559$Mr.695(a)trnddc04... >> >>>>But seriously, how fast would a singularity have to spin >>>>in order for it to fly apart? >>>>Ned >>> >>>0/0 rpm. >>>Don >>> >> >> >> Ok, how fast would the earth have to spin for you to fly >> off it (assuming you were on the equator)? What is the >> escape velocity on earth - 25,000 miles per hour? So a >> person on the equator moves through one circumference, >> which is about 25,000 miles, in 24 hours, or about 1000 >> miles per hour. So if we speeded up the earth to 25,000 >> mph, or about 25 times its current rotational speed, or >> about one rotation per hour, things would fly off the >> equator. (Including dirt and mountains, etc. - of course, >> most organic matter would burn up.) >> >> Hmmm... that's interesting - wiki is quite adamant that >> the escape velocity of a black hole is infinite. That seems >> intuitively irritating. > > >Ah, no wonder. > The escape velocity of a Black Hole is /not/ infinite, it is >merely greater than /c/ at r sub S (which defines r sub S, the >Schwartzschild Radius). > For the escape velocity to be infinite, /g/ would have to be >infinite, and the whole dam' universe would be in there already. > Since it isn't, it isn't. > >> >> That's saying that no matter how fast a black hole spins, >> it CAN'T break up?? No way! There has GOT to be some >> rotational speed at which all the mass in a black hole >> becomes unstable and begins to break up. No, stop! Don't >> lecture me. Pick a number, a huge - impossibly huge - >> number, say 500 billion trillion revolutions per second. >> Don't tell me nothing bad would happen to the back hole >> under the force of that much angular momentum! >> >> Ned >> > >The "mass" in a Black Hole is already as degenerate as a Newsfroup, >which is why a Newsfroup swallows everything you throw at it no >matter how fast it's running in circles. And no trace of light escapes?
From: Lee Rudolph on 30 Nov 2007 12:43
"Ned" <nedludd(a)ix.netcom.com> writes: >"Dennis M. Hammes" <scrawlmark(a)arvig.net> wrote in message >news:FvqdnXiTQpsOVNLanZ2dnUVZ_hWdnZ2d(a)onvoy.com... .... >> Perzackly. >> If v sub esc were infinite, r sub S (the Schwarzschild Radius) >> would be infinite, or at least the radius of the universe, i.e., >> the whole universe would already be in there. >> Since it isn't, it isn't. >> I.e., it isn't over until the fat lady singes. >> > > How do you know the whole universe isn't in there? She's not *that* fat. Lee Rudolph |