|
|
| Author |
Message |
Creighton Hogg
science forum addict
Joined: 04 May 2005
Posts: 93
|
 Posted: Thu Feb 10, 2005 4:11 pm Post subject:
applications to gauge theory
|
|
|
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? |
|
| Back to top |
|
 |
Robert C. Helling
science forum beginner
Joined: 30 Apr 2005
Posts: 22
|
| Posted: Fri Feb 11, 2005 12:42 pm Post subject:
Re: applications to gauge theory
|
|
|
On Thu, 10 Feb 2005 12:11:32 -0500, Creighton Hogg <wchogg@hep.wisc.edu> wrote:
| Quote: | 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 |
|
| Back to top |
|
|
Matt Reece
science forum beginner
Joined: 25 Apr 2005
Posts: 2
|
| Posted: Sat Feb 12, 2005 1:42 am Post subject:
Re: applications to gauge theory
|
|
|
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 hep-ph/0501128 by Erlich, Katz, Son, and
Stephanov, and 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) |
|
| Back to top |
|
|
Creighton Hogg
science forum addict
Joined: 04 May 2005
Posts: 93
|
| Posted: Sat Feb 12, 2005 1:42 am Post subject:
Re: applications to gauge theory
|
|
|
On Fri, 11 Feb 2005, Robert C. Helling wrote:
| Quote: |
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. |
|
| Back to top |
|
|
Urs Schreiber
science forum Guru Wannabe
Joined: 04 May 2005
Posts: 127
|
| Posted: Sat Feb 12, 2005 2:23 am Post subject:
Re: applications to gauge theory
|
|
|
On Fri, 11 Feb 2005, Creighton Hogg wrote:
| Quote: | 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. |
|
| Back to top |
|
|
Creighton Hogg
science forum addict
Joined: 04 May 2005
Posts: 93
|
| Posted: Sun Feb 13, 2005 2:34 pm Post subject:
Re: applications to gauge theory
|
|
|
On Fri, 11 Feb 2005, Urs Schreiber wrote:
| Quote: | 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. |
|
| Back to top |
|
|
Creighton Hogg
science forum addict
Joined: 04 May 2005
Posts: 93
|
| Posted: Sun Feb 13, 2005 2:34 pm Post subject:
Re: applications to gauge theory
|
|
|
On Fri, 11 Feb 2005, mattreece@gmail.com wrote:
| Quote: | 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 hep-ph/0501128 by Erlich, Katz, Son, and
Stephanov, and 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.
| Quote: | 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.
| Quote: | 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. |
|
| Back to top |
|
|
Urs Schreiber
science forum Guru Wannabe
Joined: 04 May 2005
Posts: 127
|
| Posted: Mon Feb 14, 2005 5:54 pm Post subject:
Re: applications to gauge theory
|
|
|
On Sun, 13 Feb 2005, Creighton Hogg wrote:
| Quote: | 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 (hep-th/0501068) . |
|
| Back to top |
|
|
Google
|
|
| Back to top |
|
|
|
|
The time now is Wed Jan 07, 2009 1:26 pm | All times are GMT
|
|
Guitar Lessons | Guitar Lessons | Debt Consolidation | Mobile Phone | Mortgage insurance
|
|
Copyright © 2004-2005 DeniX Solutions SRL
|
|
Other DeniX Solutions sites:
Electronics forum |
Medicine forum |
Unix/Linux blog |
Unix/Linux documentation |
Unix/Linux forums
|
Powered by phpBB © 2001, 2005 phpBB Group
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
Forum index
»
Science and Technology
»
Physics
»
Strings
