Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!columbia!heathcliff.columbia.edu!zdenek From: zdenek@heathcliff.columbia.edu (Zdenek Radouch) Newsgroups: sci.physics Subject: Re: Speed of light Message-ID: <3799@columbia.UUCP> Date: Fri, 7-Nov-86 22:04:31 EST Article-I.D.: columbia.3799 Posted: Fri Nov 7 22:04:31 1986 Date-Received: Sat, 8-Nov-86 18:22:56 EST References: <241@sri-arpa.ARPA> Sender: nobody@columbia.UUCP Reply-To: zdenek@heathcliff.columbia.edu.UUCP (Zdenek Radouch) Followup-To: sci.physics Distribution: net Organization: Columbia University CS Department Lines: 33 In article <241@sri-arpa.ARPA> KFL@MX.LCS.MIT.EDU writes: [In the reply to the question whether the speed of light is decreasing] > > Since 1982 the length of the meter (and hence of the inch, mile, etc) >has been defined in terms of the length of the second and the speed of >light. This means that the speed of light is now constant by >definition. Let me remind you that the constant speed of light is not an implication of the new definition of meter. The speed of light is assumed to be constant. The definition is based on that assumption. It doesn't make any sense to use this definition when questioning constant speed of light. If we find that speed of light really is changing, we are going to get rid of the definition. You are right in one thing; given this definition, it's going to be difficult. Consider this: I am going to define the length of meter in terms of the length of the second and the speed of my car. Then I can say that the speed of my car is constant... zdenek ------------------------------------------------------------------------- Men are four: He who knows and knows that he knows, he is wise - follow him; He who knows and knows not that he knows, he is asleep - wake him; He who knows not and knows that he knows not, he is simple - teach him; He who knows not and knows not that he knows not, he is a fool - shun him! zdenek@CS.COLUMBIA.EDU or ...!seismo!columbia!cs!zdenek Zdenek Radouch, 457 Computer Science, Columbia University, 500 West 120th St., New York, NY 10027