# Tagged Questions

The tag has no usage guidance.

112 views

### $\langle TT\rangle$ correlator of the boundary CFT from metric fluctuations in the bulk gravity

Is there a reference which explains how the $\langle TT\rangle$ correlation of the boundary conformal field theory (CFT) can be holographically calculated from the bulk gravity? (..I am often getting ...
499 views

### Gauss-Bonnet term in Physics

Given a 4-dimensional compact manifold (torsion free), the Euler characteristic is defined as: $$E_4 ~=~ \int \epsilon_{abcd}R^{ab} \wedge R^{cd}$$ with $R^{ab}$ is the curvature 2-form. Perturb the ...
792 views

I have been working for some time now on deriving the equations of motion (EOM) for the Gauss-Bonnet Gravity, which is given by the action: $$\int d^D x \sqrt{|g|} (R^2-4R_{ab}R^{ab}+R_{abcd}R^{abcd})... 1answer 200 views ### Euler number of the world sheet I have a question in the section 3.2 "The Polyakov path integral" in Polchinski's string theory p. 83. Given$$ \chi=\frac{1}{4 \pi} \int_M d^2 \sigma g^{1/2} R + \frac{1}{2 \pi} \int_{\partial ...
At the page 336 of Hawking, Ellis: The Large Scale Structure of Space-Time, the Gauss-Bonnet theorem is stated as $$\int_H \hat{R}\ d\hat{S} = 2\pi \chi(H) \qquad (1)$$ with \hat{R} = R_{abcd} \...