Path: news.ccsf.jp!news.heimat.gr.jp!goblin1!goblin2!goblin.stu.neva.ru!xlned.com!feeder1.xlned.com!newsfeed.freenet.de!newsfeed00.sul.t-online.de!t-online.de!border2.nntp.dca.giganews.com!nntp.giganews.com!backlog2.nntp.dca.giganews.com!nntp.scnresearch.com!news.scnresearch.com.POSTED!not-for-mail NNTP-Posting-Date: Sun, 19 Apr 2009 02:21:28 -0500 Newsgroups: alt.math,alt.math.recreational,alt.sci.math,alt.sci.nanotech,alt.sci.physics,japan.sci.math,sci.math,sci.physics Date: Sun, 19 Apr 2009 00:21:26 -0700 From: William Elliot X-X-Sender: marsh@agora.rdrop.com Subject: Re: sphere of large radius In-Reply-To: Message-ID: <20090418235802.I88792@agora.rdrop.com> References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Lines: 34 X-Usenet-Provider: http://www.giganews.com NNTP-Posting-Host: 199.26.172.34 X-AuthenticatedUsername: NoAuthUser X-Trace: sv3-C4fRzx0nP9442DPV9AZTpKw2Owxc/IsO3wvxg3Icvu+8/MBnjbH90QBCpltFxwtc2LTyXNA1Yu88DRY!Cv36fclcZ76XxzgMvbSzAImnWkr7BYDJoMspk95pmYVtdWVxy6aM+UUAIdU6gtJWN7cQx5RZ0LgC!jQD6n7J+ X-Complaints-To: abuse@scnresearch.com X-DMCA-Complaints-To: abuse@scnresearch.com X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.39 Xref: news.ccsf.jp japan.sci.math:223 On Sat, 18 Apr 2009, Jon wrote: > A sphere of large radius becomes a plane, reverses curvature and converges > on a new center. If the center is not moved then the infinite radius sphere is the plane at infinity, which though non-existing in Euclidean geometry, does exist in projective geometry. Since a naive person like you doesn't know about projective geometry but only some vague notions of Euclidean geometry, you are forced to admit that as the radius r, increases to infinity, the center will move. In this event the center will be a point at infinity which again does not exist in Euclidean geometry but only projective geometry. What do you mean by reverses curvature? A plane has zero curvature. Since the curvature went from 1/r to 0, to reverse that would mean that the curvature went from -0 to -1/r? That is incorrect. Spheres do not have negative curvature. A plane can be considered as a sphere with zero curvature. A point can be considered as a sphere with infinite curvature. Is that the convergence of the centers that you expected? Throw your trash away, it's not recreational nor does it show any knowledge of math except for some worthless artsy-feely sort of pseudo math. Are you an example of a new math educated student?