The conformal-field-theory tag has no wiki summary.
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Scale invariance Vs Conformal invariance [duplicate]
Possible Duplicate:
Why does dilation invariance often imply proper conformal invariance?
What exactly is the difference between the two. Can someone give an example of a theory which is ...
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1answer
708 views
Why/How is this Wick's theorem?
Let $\phi$ be a scalar field and then I see the following expression for the square of the normal ordered version of $\phi^2(x)$.
$$T(:\phi^2(x)::\phi^2(0):) ~=~ 2<0|T(\phi(x)\phi(0))|0>^2 $$
...
2
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1answer
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Electromagnetic current-current correlators
Let the free electromagnetic current $J_\mu(x)$ be = $:\bar{\psi}(x)\gamma_\mu Q \psi(x):$ where $::$ is the normal ordering.
In this expression why is $Q$ thought of as a "charge operator" instead ...
3
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1answer
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Wick Order and Radial Ordering in CFT
I am not so much familiar with the computations tools of conformal field theory, and I just run into an exercise asking to demonstrate the following formula (related to the bosonic field case):
...
3
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1answer
225 views
String matrix models with c>1
Question 1: What is the status of string random matrix models (~ triangulated random surfaces) with c>1?
In my limited search, I have just come across a few papers by Frank Ferrari (in 2000-2002) on ...
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2answers
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Why are conformal transformations so prevalent in physics?
What is it about conformal transformations that make them so widely applicable in physics?
These preserve angles, in other words directions (locally), and I can understand that might be useful. Also, ...
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1answer
636 views
Some questions on Conformal Field Theory, Current algebras and the Sugawara construction
Since I don't know how to add another question to an already existing topic,
I'm opening a new thread. However I'm referring to:
Beginners questions concerning Conformal Field Theory
As noted, a ...
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1answer
187 views
Conformal transformation equation
I am currently reading Kiritsis's string theory book, and something bugs in the CFT (fourth) chapter. He derives the equation that should satisfy an infinitesimal conformal transformation $x^{\mu} ...
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Holomorphic Factorization in CFT$_2$
Is a CFT$_2$ always holomorphically factorizable? I had this idea because that's what we usually see is taken in string theory e.g (taking $z$ and $\bar{z}$ as independent variables). E.g. Ginsparg ...
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How to construct a 2D conformal field on a mirrored annulus with a looping pattern?
I would like to construct a 2D conformal field on an annulus in which the inner and outer boundaries are like mirrors, and can be approximated by regular polygons (with the same number n of mirror ...
4
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1answer
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Do a 1-dimensional conformal theory exist?
can we have in physic or can we speak about 1-d conformal theory in physics ??
for example in this one dimensional theory what would be the generators $ x \partial _{x} $ or $ \partial _{x} $ ??
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1answer
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Generalized propagator
I don't understand how to calculate this generalized two-point function or propagator, used in some advanced topics in quantum field theory, a normal ordered product (denoted between ::) is subtracted ...
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1answer
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Explanation of Cardy's “a theorem”
There seems to have been some discussion of Cardy's "a-theorem" recently:
“It is shown that, for d even, the one-point function of the trace of the stress tensor on the sphere, Sd, when suitably ...
6
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1answer
157 views
About unitarity and R-charge in 2+1 superconformal field theory
How does unitarity require that every scalar operator in a $2+1$ SCFT will have to have a scaling dimension $\geq \frac{1}{2}$ ?
Why is an operator with scaling dimension exactly equal to ...
2
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1answer
383 views
How do you obtain the commutation relations at non-equal times (for the edge of a fractional quantum Hall state)?
The edge of a fractional quantum Hall state is an example of a chiral Luttinger liquid. Take, for the sake of simplicity, the edge of the Laughlin state. The Hamiltonian is:
$$H = ...
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Trace of energy momentum tensor in $CFT_1$
There is a standard procedure to show that for CFT's in dimension $d\geq 2$, the trace of stress tensor vanishes. I think I can't apply those steps when I only have one dimension, say time, because if ...
6
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1answer
373 views
Boundary Conditions Invariant Under Conformal Transformations in Electrostatics?
in two dimensional electrostatics it is assumed that the whole physical system is translationally invariant in one direction. Here, the two-dimensional Laplace equation $$\Delta \phi(x,y) = ...
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Argument for quantum theoretic conformality of $\cal{N}=2$ super-Chern-Simon's theory in $2+1$ dimensions -Part 2
This is in continuation to what I was asking here earlier -
Argument for quantum theoretic conformality of $\cal{N}=2$ super-Chern-Simon's theory in $2+1$ dimensions
Or one can look at this ...
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1answer
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Argument for quantum theoretic conformality of $\cal{N}=2$ super-Chern-Simon's theory in $2+1$ dimensions
I am using the standard symbols of $V_\mu$ for the gauge field, $\lambda$ for its fermionic superpartner and $F$ and $D$ be scalar fields which make the whole thing a $\cal{N}=2$ vector/gauge ...
3
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1answer
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Superpartner for the stress-energy tensor
I would like to understand what is meant when one introduces a generator $G(z)$ as the superpartner of the energy-momentum tensor $T(z)$.
How does one decide that this $G(z)$ should have a ...
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2answers
442 views
Question on Conformal Field Theory
Since every question has to be asked in a seperate topic,
I'm asking a question refering to the following topic:
Beginners questions concerning Conformal Field Theory
In particula I'm refering to the ...
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Beginners questions concerning Conformal Field Theory
I started reading about Conformal Field Theory a few weeks ago.
I'm from a more mathematical background. I do know Quantum Mechanics/Classical Mechanics,
but I'm not really an expert when it comes ...
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1answer
611 views
conformal, Weyl transformations, apparent discrepancies and confusions
Because of the apparent discrepancy of how some CFT and GR books define conformal transformation unlike in string theory area, I wanted to get rid of all the confusion from McGreevy's lecture notes:
...
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1answer
748 views
What is Euler Density?
can someone please explain to me what Euler Density is? I encountered it in Weyl anomaly related issues in various articles. Most of them assumes that its familiar, but I couldn't find any accessible ...
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1answer
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Can a $CFT_2$ which can't be factorized into chiral and antichiral parts and/or have a central charge not a multiple of 24 have AdS duals?
In the article Three dimensional gravity reconsidered by Ed Witten, he remarked that the CFT dual to three dimensional quantum gravity has to admit a holomorphic factorization and have a central ...
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1answer
429 views
CFTs and formalizing quantum field theory
Moshe's recent questions on formalizing quantum field theory and lattices as a definition of field theory remind me of something I occasionally idly wonder about, and maybe this site can tell me the ...
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2answers
473 views
Superconformal algebra
I had earlier also asked a question about super conformal theories and I am continuing with that, now with more specific examples. I am quite puzzled with it given that I see no book explaining even ...
0
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1answer
449 views
Question on dimensions of CFT operators (ref: MAGOO, hep-th/9905111)
Right now I am having this silly difficulty from the following:
BTW, Conformal dimension/scaling dimension is -ve of mass dimension ..right?
In p-63 of Magoo, after 3.15 eq, they said
a.) $\phi$ is ...
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4answers
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Method of Images
The method of image charges is a well-known and very useful tool for solving problems in electrostatics.
Unfortunately, when I was taught this method, it was presented simply as an algorithm. No real ...
4
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2answers
244 views
Witten Index and letter partition function
I haven't seen any reference which explains these things and I am not sure of all the steps of the argument or the equations. I am trying to reproduce here a sequence of arguments that I have mostly ...
8
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2answers
459 views
Superconformal theories
Can anyone tell me where can I read about the notion of "short" and "long" representations? Like what they are etc.
From where can I learn the arguments which show that the bosonic subalgebra of ...
