Lubos Motl
Sep27-04, 11:37 AM
<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>Hi!\n\nI have just a couple of minutes. Juan Maldacena has just explained us\ntheir paper with Oleg Lunin and Hai Lin\n\nhttp://arxiv.org/abs/hep-th/0409174\n\nand it is extremely interesting and relevant for our discussions about\nsumming over different spacetime topologies in string theory.\n\nThey consider 1/2 BPS states in AdS5 x S5 (and other backgrounds), which\nare somewhat analogous to the pp-wave states. However, now they label\nthese states using the free fermions - much like if you imagine the case\nof two-dimensional string theory - in this case, you must forget about a\ncouple dimensions (a plenty of degrees of freedom); this restriction comes\nby the requirement of supersymmetry.\n\nOK, so this 1/2 BPS sector then looks like free fermions - much like if\nyou study a matrix model with a single boson - and you create states of\nthe Fermi liquid. The droplets can have various shapes, and they design\nvarious geometries asymptotic to AdS5 x S5 or the pp-wave, which can\nhowever have many different topologies.\n\nTherefore many states with different topologies, "handles", are included\nin the gauge theory (even macroscopically large and smooth manifolds with\ndifferent topologies), and you can explicitly see them in this\napproximation. These extra topologies also contribute to the path\nintegral. But they probably don\'t include the infinitely long wormholes\nthat Hawking would need for baby universes etc.\n\nThis is probably a bit chaotic description, but let me certainly recommend\nyou their paper.\n\nAll the best\nLubos\n_____________________________________ _________________________________________\nE-mail: lumo@matfyz.cz fax: +1-617/496-0110 Web: http://lumo.matfyz.cz/\neFax: +1-801/454-1858 work: +1-617/384-9488 home: +1-617/868-4487 (call)\n^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\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>Hi!
I have just a couple of minutes. Juan Maldacena has just explained us
their paper with Oleg Lunin and Hai Lin
http://arxiv.org/abs/http://www.arxiv.org/abs/hep-th/0409174
and it is extremely interesting and relevant for our discussions about
summing over different spacetime topologies in string theory.
They consider 1/2 BPS states in AdS5 x S5 (and other backgrounds), which
are somewhat analogous to the pp-wave states. However, now they label
these states using the free fermions - much like if you imagine the case
of two-dimensional string theory - in this case, you must forget about a
couple dimensions (a plenty of degrees of freedom); this restriction comes
by the requirement of supersymmetry.
OK, so this 1/2 BPS sector then looks like free fermions - much like if
you study a matrix model with a single boson - and you create states of
the Fermi liquid. The droplets can have various shapes, and they design
various geometries asymptotic to AdS5 x S5 or the pp-wave, which can
however have many different topologies.
Therefore many states with different topologies, "handles", are included
in the gauge theory (even macroscopically large and smooth manifolds with
different topologies), and you can explicitly see them in this
approximation. These extra topologies also contribute to the path
integral. But they probably don't include the infinitely long wormholes
that Hawking would need for baby universes etc.
This is probably a bit chaotic description, but let me certainly recommend
you their paper.
All the best
Lubos
__{_______________________________________________ _____________________________}
E-mail: lumo@matfyz.cz fax: +1-617/496-0110 Web: http://lumo.matfyz.cz/
eFax: +1-801/454-1858 work: +1-617/384-9488 home: +1-617/868-4487 (call)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I have just a couple of minutes. Juan Maldacena has just explained us
their paper with Oleg Lunin and Hai Lin
http://arxiv.org/abs/http://www.arxiv.org/abs/hep-th/0409174
and it is extremely interesting and relevant for our discussions about
summing over different spacetime topologies in string theory.
They consider 1/2 BPS states in AdS5 x S5 (and other backgrounds), which
are somewhat analogous to the pp-wave states. However, now they label
these states using the free fermions - much like if you imagine the case
of two-dimensional string theory - in this case, you must forget about a
couple dimensions (a plenty of degrees of freedom); this restriction comes
by the requirement of supersymmetry.
OK, so this 1/2 BPS sector then looks like free fermions - much like if
you study a matrix model with a single boson - and you create states of
the Fermi liquid. The droplets can have various shapes, and they design
various geometries asymptotic to AdS5 x S5 or the pp-wave, which can
however have many different topologies.
Therefore many states with different topologies, "handles", are included
in the gauge theory (even macroscopically large and smooth manifolds with
different topologies), and you can explicitly see them in this
approximation. These extra topologies also contribute to the path
integral. But they probably don't include the infinitely long wormholes
that Hawking would need for baby universes etc.
This is probably a bit chaotic description, but let me certainly recommend
you their paper.
All the best
Lubos
__{_______________________________________________ _____________________________}
E-mail: lumo@matfyz.cz fax: +1-617/496-0110 Web: http://lumo.matfyz.cz/
eFax: +1-801/454-1858 work: +1-617/384-9488 home: +1-617/868-4487 (call)
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