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<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no,location=no, scrollbars=yes,resizable=yes,status=no,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Urs Schreiber wrote in message news:<Pine.LNX.4.31.0406031214100.16355-100000@feynman.harvard.edu>...\n\n> On Wed, 2 Jun 2004, Squark wrote:\n>\n> > What precisely is the configuration space that you are talking about?\n>\n> By the ADM method config space is the space of field configurations on\n> spatial hyperslices - Wheeler\'s "superspace" (not that of supersymmetry) or\n> some min- or midi- superspace approximation thereof, retaining only a finite\n> number of degrees of freedom\n\nNow I see what you\'re talking about. Well, a Killing vector\nin this configuration space is essentially a continous global\nsymmetry of the theory. However, Michael Douglas writes in\n"The statistics of M-theory vacua" (hep-th/0303194), page 12,\nthat probably no such continous global symmetry exists. The\narticle he is referring to (T.Banks and L.J.Dixon, Nuclear\nPhysics, B307, 93) dates back to 1988 and is not avaible on\nthe net, as far as I know, so unfortunatelly I have no access\nto it currently. I certainly know about no such symmetry. The\none argument I can think about against it is that it would be\nassociated with a conserved charged whose existence in a\ngravitational theory conflicts the no-hair theorem.\n\n> exp(E10) is shorthand for the "group" associated with the hyperbolic\n> Kac-Moody algabra E10.\n>\n> One reason to conjecture that this humongous group is the full configuration\n> space of M-theory is that apparently the full dynamics of 11D sugra is\n> obtained by geodesic motion in a (small) subsector of this group.\n\nI haven\'t peeked at the references you supplied yet, but it\nis far from obvious what would be meant by "the full\nconfiguration space pf M-theory". According to the\ndefinition you gave earlier, (classical) gravitational\ndynamics would not generate trajectories in this\nconfiguration space but rather subspaces of\ninfinite dimension (and codimension), each such subspace\ncorresponding to all of the spacelike slices of a given\nsolution. I\'d say the system is not described by a particle\nin configuration space but rather by and infinity-brane!\n\nBest regards,\nSquark.\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>Urs Schreiber wrote in message news:<Pine.LNX.4.31.0406031214100.16...arvard.edu>...
> On Wed, 2 Jun 2004, Squark wrote:
>
> > What precisely is the configuration space that you are talking about?
>
> By the ADM method config space is the space of field configurations on
> spatial hyperslices - Wheeler's "superspace" (not that of supersymmetry) or
> some [itex]min-[/itex] or midi- superspace approximation thereof, retaining only a finite
> number of degrees of freedom
Now I see what you're talking about. Well, a Killing vector
in this configuration space is essentially a continous global
symmetry of the theory. However, Michael Douglas writes in
"The statistics of M-theory vacua" (http://www.arxiv.org/abs/hep-th/0303194), page 12,
that probably no such continous global symmetry exists. The
article he is referring to (T.Banks and L.J.Dixon, Nuclear
Physics, B307, 93) dates back to 1988 and is not avaible on
the net, as far as I know, so unfortunatelly I have no access
to it currently. I certainly know about no such symmetry. The
one argument I can think about against it is that it would be
associated with a conserved charged whose existence in a
gravitational theory conflicts the no-hair theorem.
> [itex]\exp(E10)[/itex] is shorthand for the "group" associated with the hyperbolic
> Kac-Moody algabra E10.
>
> One reason to conjecture that this humongous group is the full configuration
> space of M-theory is that apparently the full dynamics of 11D sugra is
> obtained by geodesic motion in a (small) subsector of this group.
I haven't peeked at the references you supplied yet, but it
is far from obvious what would be meant by "the full
configuration space pf M-theory". According to the
definition you gave earlier, (classical) gravitational
dynamics would not generate trajectories in this
configuration space but rather subspaces of
infinite dimension (and codimension), each such subspace
corresponding to all of the spacelike slices of a given
solution. I'd say the system is not described by a particle
in configuration space but rather by and infinity-brane!
Best regards,
Squark.
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