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Article #38

Re: Borel measure question

#38
From: Jens Peter Reus Christensen
Date: Wed, 26 Aug 1992 15:36
39 lines
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In article <17dh96INN35s@function.mps.ohio-state.edu> edgar@function.mps.ohio-state.edu (Gerald Edgar) writes:

   (I seem to remember seeing this, but can't remember for sure.)

   Let S be a metric space.  Write B(x,r) for the open ball with center
   x and radius r.  Let mu be a finite Borel measure on S.  For fixed
   r>0, does it follow that the function

      x --->  mu(B(x,r))

   (from S to R) is a Borel function of x ?

   Assume, if necessary, that S is separable.
   -- 
     Gerald A. Edgar                Internet:  edgar@mps.ohio-state.edu
     Department of Mathematics      Bitnet:    EDGAR@OHSTPY
     The Ohio State University      telephone: 614-292-0395 (Office)
     Columbus, OH 43210             -292-4975 (Math. Dept.) -292-1479 (Dept. Fax)

*****
I do think this function is lower semicontinuous! Thus always
measurable!

--
|--------------------------------------------------------------------------|
|  Jens Peter Reus Christensen   |                                         |
|  Associate professor, Dr. Phil.|                                         |
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|  University of Copenhagen      |                                         |
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From: reus@klein.euromath.dk (Jens Peter Reus Christensen)
Subject: Re: Borel measure question
References: <17dh96INN35s@function.mps.ohio-state.edu>
Message-ID: <REUS.92Aug26103619@klein.euromath.dk>
Sender: Daniel Grayson <dan@math.uiuc.edu>
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In-Reply-To: edgar@function.mps.ohio-state.edu's message of 25 Aug 92 14:49:10 GMT
Date: Wed, 26 Aug 1992 15:36:19 GMT
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