🚀 go-pugleaf

In article <1992Aug11.154818.26748@galois.mit.edu> jbaez@nevanlinna.mit.edu (John C. Baez) writes:
>In article <1992Aug10.202618.1433@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
>>In article <1992Aug10.184700.3204@sbcs.sunysb.edu> rscott@csws1.ic.sunysb.edu (Robert Scott) writes:
>
>>>AS FOR YOUR COMPLAINT THAT LIGHT-SPEED DELAYS CAN NOT EXPLAIN WHY
>>>TIME-DILATION OCCURS, I THINK THAT YOU GOT IT EXACTLY BACKWARDS.  THAT
>>>IS, IT'S NOT THAT THE ROBOTS IN THE GAME DON'T EXHIBIT TIME-DILATION;
>>>RATHER IT'S THAT THERE ISN'T EVEN ANY STANDARD AGAINST WHICH YOU CAN
>>>ASK WHETHER THEIR TIME IS DILATED.  THAT IS, THE SYMMETRY GROUP
>>>OPERATING HERE, WHICH IS THE INTERSECTION OF THE GROUP OF AFFINE
>>>TRANSFORMATIONS (PRESERVING THE STRUCTURE RELATED TO INERTIAL MOTION
>>>AND THE SPECIFICATION OF SPACE-TIME POINTS IN TERMS OF AFFINE
>>>COMBINATIONS) AND THE GROUP OF "LORENTZIAN CONFORMAL" TRANSFORMATIONS
>>>(PRESERVING THE STRUCTURE RELATED TO THE LIGHT-SPEED SIGNALLING
>>>PROTOCOL) IS ALMOST, BUT NOT QUITE, JUST THE POINCARE GROUP OF SPECIAL
>>>RELATIVITY.  
>>
>>     What?   If there is no relation between the time standards, there
>>     is complete anarchy and you cannot describe the kinematics of the 
>>     system at all.
>
>The group Scott is referring to here, Poincare transformations plus
>scaling, is sometimes called the Weyl group and is indeed a symmetry of
>relativistic theories of *massless* particles.  See my forthcoming post
>on symmetry for more.

     I realize that.  How does he impose it? 

                            dale bass
-- 
C. R. Bass                                           crb7q@virginia.edu
Department of Mechanical and Aerospace Engineering
University of Virginia
Charlottesville, Virginia                            (804) 924-7926