applications to gauge theory [Archive]

Creighton Hogg

Feb10-05, 11:11 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,\nI\'ve heard casually in passing that there\'s dualities that allow string\ntheory techniques to be applied to gauge theories like QCD, which might\nhelp with calculations?\nIf this is true, I was wondering if there\'s good articles to start reading\nabout the subject and maybe some keywords to use to find articles on arXiv\nand google-scholar?\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've heard casually in passing that there's dualities that allow string
theory techniques to be applied to gauge theories like QCD, which might
help with calculations?
If this is true, I was wondering if there's good articles to start reading
about the subject and maybe some keywords to use to find articles on arXiv
and google-scholar?

Robert C. Helling

Feb11-05, 07:42 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>On Thu, 10 Feb 2005 12:11:32 -0500, Creighton Hogg <wchogg@hep.wisc.edu> wrote:\n\n> I\'ve heard casually in passing that there\'s dualities that allow string\n> theory techniques to be applied to gauge theories like QCD, which might\n> help with calculations?\n> If this is true, I was wondering if there\'s good articles to start reading\n> about the subject and maybe some keywords to use to find articles on arXiv\n> and google-scholar?\n\nThe keywords are \'twistor\' and \'MHV\'. Once again, this was started by\nBig Ed it is probably a good idea to start with his paper before you\nget into the more technical stuff.\n\nRobert\n\n\n[Moderator\'s note: I thought that Creighton meant simply AdS/CFT\ncorrespondence. The question whether any kind of string theory is useful\nor completely correct for the twistor gauge theory calculations has\nbeen re-opened. LM]\n\n-\n-\n..oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oO o.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oO\nRobert C. Helling School of Science and Engineering\nInternational University Bremen\nprint "Just another Phone: +49 421-200 3574\nstupid .sig\\n"; http://www.aei-potsdam.mpg.de/~helling\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>On Thu, 10 Feb 2005 12:11:32 -0500, Creighton Hogg <wchogg@hep.wisc.edu> wrote:

> I've heard casually in passing that there's dualities that allow string
> theory techniques to be applied to gauge theories like QCD, which might
> help with calculations?
> If this is true, I was wondering if there's good articles to start reading
> about the subject and maybe some keywords to use to find articles on arXiv
> and google-scholar?

The keywords are 'twistor' and 'MHV'. Once again, this was started by
Big Ed it is probably a good idea to start with his paper before you
get into the more technical stuff.

Robert

[Moderator's note: I thought that Creighton meant simply AdS/CFT
correspondence. The question whether any kind of string theory is useful
or completely correct for the twistor gauge theory calculations has
been re-opened. LM]

-
-
..oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo. oOo.oOo.oOo.oOo.oOo.oOo.oOo.oO
Robert C. Helling School of Science and Engineering
International University Bremen
print "Just another Phone: +49 421-200 3574
stupid .sig\n"; http://www.aei-potsdam.mpg.de/~helling

mattreece@gmail.com

Feb11-05, 08:42 PM

<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>If you mean AdS/CFT, the idea is that string theory on AdS_5 x S^5 is\ndual to N=4 SUSY Yang-Mills. One can then attempt to turn this into\nsomething more like QCD by adding branes to your five-dimensional\nspace. Some recent phenomenological papers looking at this sort of\n"AdS/QCD" model include hep-ph/0501128 by Erlich, Katz, Son, and\nStephanov, and hep-ph/0501218 by Da Rold and Pomarol. Both of those\npapers look at chiral symmetry breaking from the five-dimensional\nholographic perspective. The references in them should lead you to the\nearlier work along these lines.\n\nAs a model of QCD, these 5D theories get results accurate at the 5% to\n10% level for at least the lighter hadrons. It\'s not clear to me that\nthere\'s a huge advantage here over other approaches to QCD, but I\'m no\nexpert. Similar ideas are very useful for different approaches to\nbeyond-the-Standard-Model model-building, though.\n\nA general reference for this sort of thing is the paper "Holography and\nPhenomenology" by Arkani-Hamed, Porrati, and Randall, which also has\nreferences to the early stringy papers by Maldacena and others.\n\n--\nMatt Reece (mreece -at- lepp dot cornell dot edu)\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>If you mean AdS/CFT, the idea is that string theory on AdS_5 x S^5 is
dual to N=4 SUSY Yang-Mills. One can then attempt to turn this into
something more like QCD by adding branes to your five-dimensional
space. Some recent phenomenological papers looking at this sort of
"AdS/QCD" model include http://www.arxiv.org/abs/hep-ph/0501128 by Erlich, Katz, Son, and
Stephanov, and http://www.arxiv.org/abs/hep-ph/0501218 by Da Rold and Pomarol. Both of those
papers look at chiral symmetry breaking from the five-dimensional
holographic perspective. The references in them should lead you to the
earlier work along these lines.

As a model of QCD, these 5D theories get results accurate at the 5% to
10% level for at least the lighter hadrons. It's not clear to me that
there's a huge advantage here over other approaches to QCD, but I'm no
expert. Similar ideas are very useful for different approaches to
beyond-the-Standard-Model model-building, though.

A general reference for this sort of thing is the paper "Holography and
Phenomenology" by Arkani-Hamed, Porrati, and Randall, which also has
references to the early stringy papers by Maldacena and others.

--
Matt Reece (mreece -at- lepp dot cornell dot edu)

Creighton Hogg

Feb11-05, 08:42 PM

<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>\n\nOn Fri, 11 Feb 2005, Robert C. Helling wrote:\n>\n> The keywords are \'twistor\' and \'MHV\'. Once again, this was started by\n> Big Ed it is probably a good idea to start with his paper before you\n> get into the more technical stuff.\n>\n> Robert\n>\n>\n> [Moderator\'s note: I thought that Creighton meant simply AdS/CFT\n> correspondence. The question whether any kind of string theory is useful\n> or completely correct for the twistor gauge theory calculations has\n> been re-opened. LM]\n\nWhy don\'t I explain my interest. I\'ve become very interested in QCD and\nI\'ve seen that there are alot of problems with non-perturbative\ncalculations and the need for corrections higher than NLO or NNLO, which\nis not readily tractable.\nI\'ve heard of gauge/string duality and was wondering if there ways that\nnon-perturbative calculations in a gauge theory could be mapped to much\neasier calculations in string theory in some limit. From Lubos\' comments\nit sounds as though this is related to the AdS/CFT correspondence I\'ve\nheard of, but never read up on.\n\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>On Fri, 11 Feb 2005, Robert C. Helling wrote:
>
> The keywords are 'twistor' and 'MHV'. Once again, this was started by
> Big Ed it is probably a good idea to start with his paper before you
> get into the more technical stuff.
>
> Robert
>
>
> [Moderator's note: I thought that Creighton meant simply AdS/CFT
> correspondence. The question whether any kind of string theory is useful
> or completely correct for the twistor gauge theory calculations has
> been re-opened. LM]

Why don't I explain my interest. I've become very interested in QCD and
I've seen that there are alot of problems with non-perturbative
calculations and the need for corrections higher than NLO or NNLO, which
is not readily tractable.
I've heard of gauge/string duality and was wondering if there ways that
non-perturbative calculations in a gauge theory could be mapped to much
easier calculations in string theory in some limit. From Lubos' comments
it sounds as though this is related to the AdS/CFT correspondence I've
heard of, but never read up on.

Urs Schreiber

Feb11-05, 09:23 PM

<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>On Fri, 11 Feb 2005, Creighton Hogg wrote:\n\n> I\'ve heard of gauge/string duality and was wondering if there ways that\n> non-perturbative calculations in a gauge theory could be mapped to much\n> easier calculations in string theory in some limit. From Lubos\' comments\n> it sounds as though this is related to the AdS/CFT correspondence I\'ve\n> heard of, but never read up on.\n\nYup, the point is that under the duality strong coupling on the CFT side\nmaps to weak coupling on the AdS side.\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>On Fri, 11 Feb 2005, Creighton Hogg wrote:

> I've heard of gauge/string duality and was wondering if there ways that
> non-perturbative calculations in a gauge theory could be mapped to much
> easier calculations in string theory in some limit. From Lubos' comments
> it sounds as though this is related to the AdS/CFT correspondence I've
> heard of, but never read up on.

Yup, the point is that under the duality strong coupling on the CFT side
maps to weak coupling on the AdS side.

Creighton Hogg

Feb13-05, 09:34 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>On Fri, 11 Feb 2005, Urs Schreiber wrote:\n\n> On Fri, 11 Feb 2005, Creighton Hogg wrote:\n>\n> > I\'ve heard of gauge/string duality and was wondering if there ways that\n> > non-perturbative calculations in a gauge theory could be mapped to much\n> > easier calculations in string theory in some limit. From Lubos\' comments\n> > it sounds as though this is related to the AdS/CFT correspondence I\'ve\n> > heard of, but never read up on.\n>\n> Yup, the point is that under the duality strong coupling on the CFT side\n> maps to weak coupling on the AdS side.\n\nAlthough, how practical is this duality really? In order to apply it to\nsomething like QCD, you have to assume massless quarks and no running of\nthe coupling constant (since the theory has to be conformal). Also, I\nthink it\'s still not so much QCD as it is a N=4 SUSY version of QCD.\nThat seems to me like an awful lot of systematic error introduced into any\nresults you get out, but that is just my first impression from skimming.\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>On Fri, 11 Feb 2005, Urs Schreiber wrote:

> On Fri, 11 Feb 2005, Creighton Hogg wrote:
>
> > I've heard of gauge/string duality and was wondering if there ways that
> > non-perturbative calculations in a gauge theory could be mapped to much
> > easier calculations in string theory in some limit. From Lubos' comments
> > it sounds as though this is related to the AdS/CFT correspondence I've
> > heard of, but never read up on.
>
> Yup, the point is that under the duality strong coupling on the CFT side
> maps to weak coupling on the AdS side.

Although, how practical is this duality really? In order to apply it to
something like QCD, you have to assume massless quarks and no running of
the coupling constant (since the theory has to be conformal). Also, I
think it's still not so much QCD as it is a N=4 SUSY version of QCD.
That seems to me like an awful lot of systematic error introduced into any
results you get out, but that is just my first impression from skimming.

Creighton Hogg

Feb13-05, 09:34 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>On Fri, 11 Feb 2005, mattreece@gmail.com wrote:\n\n> If you mean AdS/CFT, the idea is that string theory on AdS_5 x S^5 is\n> dual to N=4 SUSY Yang-Mills. One can then attempt to turn this into\n> something more like QCD by adding branes to your five-dimensional\n> space. Some recent phenomenological papers looking at this sort of\n> "AdS/QCD" model include hep-ph/0501128 by Erlich, Katz, Son, and\n> Stephanov, and hep-ph/0501218 by Da Rold and Pomarol. Both of those\n> papers look at chiral symmetry breaking from the five-dimensional\n> holographic perspective. The references in them should lead you to the\n> earlier work along these lines.\n\nI actually just found the paper by Erlich et al shortly before reading\nyour post! It seems fairly interesting, but it does appear to be very\nmuch a "proof of concept" paper rather than presenting fully usable tools\nfor calculation. I was quite pleased, though, to the authors very\nexplicitly outline the region of applicablity of their results.\n\n> As a model of QCD, these 5D theories get results accurate at the 5% to\n> 10% level for at least the lighter hadrons. It\'s not clear to me that\n> there\'s a huge advantage here over other approaches to QCD, but I\'m no\n> expert. Similar ideas are very useful for different approaches to\n> beyond-the-Standard-Model model-building, though.\n\nWell, that doesn\'t sound like it is really good enough yet as an\nalternative to more typical methods of doing calculations in QCD. I\'ll\nstill keep digging into this a little though.\n\n> A general reference for this sort of thing is the paper "Holography and\n> Phenomenology" by Arkani-Hamed, Porrati, and Randall, which also has\n> references to the early stringy papers by Maldacena and others.\n\nThanks, that\'s a paper I didn\'t know about! It sounds quite useful.\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>On Fri, 11 Feb 2005, mattreece@gmail.com wrote:

> If you mean AdS/CFT, the idea is that string theory on AdS_5 x S^5 is
> dual to N=4 SUSY Yang-Mills. One can then attempt to turn this into
> something more like QCD by adding branes to your five-dimensional
> space. Some recent phenomenological papers looking at this sort of
> "AdS/QCD" model include http://www.arxiv.org/abs/hep-ph/0501128 by Erlich, Katz, Son, and
> Stephanov, and http://www.arxiv.org/abs/hep-ph/0501218 by Da Rold and Pomarol. Both of those
> papers look at chiral symmetry breaking from the five-dimensional
> holographic perspective. The references in them should lead you to the
> earlier work along these lines.

I actually just found the paper by Erlich et al shortly before reading
your post! It seems fairly interesting, but it does appear to be very
much a "proof of concept" paper rather than presenting fully usable tools
for calculation. I was quite pleased, though, to the authors very
explicitly outline the region of applicablity of their results.

> As a model of QCD, these 5D theories get results accurate at the 5% to
> 10% level for at least the lighter hadrons. It's not clear to me that
> there's a huge advantage here over other approaches to QCD, but I'm no
> expert. Similar ideas are very useful for different approaches to
> beyond-the-Standard-Model model-building, though.

Well, that doesn't sound like it is really good enough yet as an
alternative to more typical methods of doing calculations in QCD. I'll
still keep digging into this a little though.

> A general reference for this sort of thing is the paper "Holography and
> Phenomenology" by Arkani-Hamed, Porrati, and Randall, which also has
> references to the early stringy papers by Maldacena and others.

Thanks, that's a paper I didn't know about! It sounds quite useful.

Urs Schreiber

Feb14-05, 12:54 PM

<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>On Sun, 13 Feb 2005, Creighton Hogg wrote:\n\n> On Fri, 11 Feb 2005, Urs Schreiber wrote:\n>\n> > On Fri, 11 Feb 2005, Creighton Hogg wrote:\n> >\n> > > I\'ve heard of gauge/string duality and was wondering if there ways that\n> > > non-perturbative calculations in a gauge theory could be mapped to much\n> > > easier calculations in string theory in some limit. From Lubos\' comments\n> > > it sounds as though this is related to the AdS/CFT correspondence I\'ve\n> > > heard of, but never read up on.\n> >\n> > Yup, the point is that under the duality strong coupling on the CFT side\n> > maps to weak coupling on the AdS side.\n>\n> Although, how practical is this duality really?\n\n\nThere is currently quite some activity on trying to figure this out. See\nfor instance\n\n- Dixon\'s strings04 talk\n\nhttp://strings04.lpthe.jussieu.fr/talks/Dixon.pdf .\n\n\n- Nastase: The RHIC fireball as a dual black hole (hep-th/0501068) .\n\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>On Sun, 13 Feb 2005, Creighton Hogg wrote:

> On Fri, 11 Feb 2005, Urs Schreiber wrote:
>
> > On Fri, 11 Feb 2005, Creighton Hogg wrote:
> >
> > > I've heard of gauge/string duality and was wondering if there ways that
> > > non-perturbative calculations in a gauge theory could be mapped to much
> > > easier calculations in string theory in some limit. From Lubos' comments
> > > it sounds as though this is related to the AdS/CFT correspondence I've
> > > heard of, but never read up on.
> >
> > Yup, the point is that under the duality strong coupling on the CFT side
> > maps to weak coupling on the AdS side.
>
> Although, how practical is this duality really?

There is currently quite some activity on trying to figure this out. See
for instance

- Dixon's strings04 talk

http://strings04.lpthe.jussieu.fr/talks/Dixon.pdf .

- Nastase: The RHIC fireball as a dual black hole (http://www.arxiv.org/abs/hep-th/0501068) .