Titanomachy
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From: Androcles on 29 Nov 2007 05:13 "Invisible Lurker" <ansaman(a)gmail.com> wrote in message news:1Rq3j.4896$k27.2249(a)bignews2.bellsouth.net... : Ned said: : > "tadchem" <tadchem(a)comcast.net> wrote in message : > news:62d7fd94-63ee-4322-9087-acd0f710efa9(a)t47g2000hsc.googlegroups.com... : >> : >>> I don't buy it. The earth's rotation is slowing down. It is : >>> slowing down for the same reason that the moon (and all moons) : >>> slow down and ultimately present the same 'face' to the object : >>> they are circling: The gravitational pull of the larger object : >>> inhibits the rotation of the smaller object. : >> : >> What you are saying here is that "The gravitational pull of the : >> larger object (Earth) inhibits the rotation of the smaller object : >> (the moon)", which is a fait accompli. The moon no longer rotates : >> relative to the gradient in the earth's gravitational field. : >> What you are ignoring (or mis-stating) is that the *differential* : >> gravitation (tide-raising force) works both ways, so the moon's : >> gravitation (and to a lesser extent the sun's as well) is what : >> is slowing the earth's rotation. : >> The earth is not perfectly rigid. It flexes as it spins in the : >> moon's gravity because the part that is facing the moon feels a : >> stronger gravitational effect from the moon than the part facing : >> away from the moon. : >> Tidal friction converts kinetic energy of rotation to thermal : >> energy, while the total angular momentum of the system is : >> conserved. : >> The earth is still spinning fast, but friction from the interaction : >> with the moon's gravitational field raises tides in the water and : >> the land, heating both while slowing down rotation. When the earth : >> has slowed enough that it keeps one face towards the moon, then the : >> interaction with the moon's gravity will no longer produce tides, : >> and the sun's gravity will become the main factor slowing down the : >> rotation of the earth. : >> http://en.wikipedia.org/wiki/Tidal_locking : >> http://www.badastronomy.com/bad/misc/tides.html : >> http://www.jal.cc.il.us/~mikolajsawicki/tides_new2.pdf : >> Eventually, if the sun, earth, and moon last that long, the moon : >> and earth will recombine and become a single body locked into : >> position facing the sun (at the moment I don't want to calculate : >> how long that may take). : >> Tom Davidson : >> Richmond, VA : >> : > : > Oh, take a shot. Is it more like a billion years or more : > like a 100 million years? : > : > But one question... If all motion is relative, how does : > the earth know that the moon is revolving around IT, rather : > than IT revolving around the moon? : > : > Ned : : The moon is so large that it is essentially a binary system : with the LaGrange points far outside the earth. The moon : is no puny satellite. : : -- : Invisible Lurker : Really Not Here or There, Either Not all there.
From: dt on 29 Nov 2007 09:53 Dennis M. Hammes wrote: > Ned wrote: > >> >> But one question... If all motion is relative, how does >> the earth know that the moon is revolving around IT, rather >> than IT revolving around the moon? >> >> Ned >> > > If all motion is relative, how do you explain teh couch potato? Newton's first law. Or Newton's brother-in-law. DT
From: Ned on 29 Nov 2007 10:00 "Dennis M. Hammes" <scrawlmark(a)arvig.net> wrote in message news:8fqdnXiYroxB79PanZ2dnUVZ_h-vnZ2d(a)onvoy.com... > >> But one question... If all motion is relative, how does >> the earth know that the moon is revolving around IT, rather >> than IT revolving around the moon? >> Ned > > If all motion is relative, how do you explain teh couch potato? > Couch potatoes are singularities. They absorb everything and nothing comes out, not even light. How fast would a singularity have to spin in order for it to come apart? Ned
From: Ned on 29 Nov 2007 10:01 "Dennis M. Hammes" <scrawlmark(a)arvig.net> wrote in message news:8fqdnXuYrowz7tPanZ2dnUVZ_h_inZ2d(a)onvoy.com... > >>>> But one question... If all motion is relative, how does >>>> the earth know that the moon is revolving around IT, rather >>>> than IT revolving around the moon? >>>> Ned >>> >>> What does it mean to say that the earth "knows" something? >>> Don >> >> What does it mean to say that one thing goes "around" another >> thing, when all motion is relative? > > Why is relatives' motion "around" each other called a "square" dance? > Because it's only done by squares, dadyo! Ned
From: Ned on 29 Nov 2007 10:05
"Dennis M. Hammes" <scrawlmark(a)arvig.net> wrote in message news:6-udnaMEpcIQ5dPanZ2dnUVZ_vCknZ2d(a)onvoy.com... > >>>> Thus do I never come back, because I have never left. >>> >>> Then that means you're stuck here with us. >>> Don >> >> Ah, but alas, the reason I have never left is because I have never >> been here. >> Ned > > If you have never been here, you might be a Buddhist. > If you have never been anywhere, you might be a couch potato. > If you are not here now, /I/ might be a Buddhist. > I fundamentally do not exist and at the present moment will not be annihilated. Ned |