Searcharxiv⌕ Search

arXiv subjects

Alexander Belavin

Publications and source records attributed to Alexander Belavin.

27 records · Page 2Linked to original sources
arXiv2017

A new approach for computing the geometry of the moduli spaces for a Calabi-Yau manifold

It is known that moduli spaces of Calabi-Yau (CY) manifolds are special Kähler manifolds. This structure determines the corresponding low-energy effective theory which arises in superstring compactifications on CY manifolds. In the case, where CY manifold is given as a hypersurface in the weighted projective space, we propose a new procedure for computing the Kähler potential of the moduli space. Our method is based on the fact that the moduli space of CY manifolds is a marginal subspace of the Frobenius manifold which arises on the deformation space of the corresponding Landau--Ginzburg superpotential.

hep-th↗
arXiv2016

On exact solution of topological CFT models based on Kazama-Suzuki cosets

We compute the flat coordinates on the Frobenius manifolds arising on the deformation space of Gepner $\hat{SU}(3)_k$ chiral rings. The explicit form of the flat coordinates is important for exact solutions of models of topological CFT and 2d Liouville gravity. We describe the case k=3, which is of particular interest because apart from the relevant chiral fields it contains a marginal one. Whereas marginal perturbations are relevant in different contexts, their analysis requires additional care compared to the relevant perturbations.

hep-th↗
arXiv2016

Flat coordinates for Saito Frobenius manifolds and String theory

It was shown in \cite{DVV} for $2d$ topological Conformal field theory (TCFT) \cite{EY,W} and more recently in \cite{BSZ}-\cite{BB2} for the non-critical String theory \cite{P}-\cite{BAlZ} that a number of models of these two types can be exactly solved using their connection with the Frobenius manifold (FM) structure introduced by Dubrovin\cite{Dub}. More precisely these models are connected with a special case of FMs, so called Saito Frobenius manifolds (SFM)\cite{Saito} (originally called Flat structure together with the Flat coordinate system), which arise on the space of the versal deformations of the isolated Singularities after choosing of a suitabe so-called Primitive form, and which also arises on the quotient spaces by reflection groups. In this paper we explore the connection of the models of TCFT and non-critical String theory with SFM. The crucial point for obtaining an explicit expression for the correlators is finding the flat coordinates of SFMs as functions of the parameters of the deformed singularity. We suggest a direct way to find the flat coordinates, using the integral representation for the solutions of Gauss-Manin system connected with the corresponding SFM for a simple singularity. Also, we address the possible generalization of our approach for the models investigated in \cite{Gep} which are ${SU(N)_k}/({SU(N-1)_{k+1} \times U(1)})$ Kazama-Suzuki theories \cite{KS}.

hep-th↗
arXiv2014

Minimal Liouville Gravity correlation numbers from Douglas string equation

We continue the study of $(q,p)$ Minimal Liouville Gravity with the help of Douglas string equation. We generalize the results of \cite{Moore:1991ir}, \cite{Belavin:2008kv}, where Lee-Yang series $(2,2s+1)$ was studied, to $(3,3s+p_0)$ Minimal Liouville Gravity, where $p_0=1,2$. We demonstrate that there exist such coordinates $τ_{m,n}$ on the space of the perturbed Minimal Liouville Gravity theories, in which the partition function of the theory is determined by the Douglas string equation. The coordinates $τ_{m,n}$ are related in a non-linear fashion to the natural coupling constants $λ_{m,n}$ of the perturbations of Minimal Lioville Gravity by the physical operators $O_{m,n}$. We find this relation from the requirement that the correlation numbers in Minimal Liouville Gravity must satisfy the conformal and fusion selection rules. After fixing this relation we compute three- and four-point correlation numbers when they are not zero. The results are in agreement with the direct calculations in Minimal Liouville Gravity available in the literature \cite{Goulian:1990qr}, \cite{Zamolodchikov:2005sj}, \cite{Belavin:2006ex}.

hep-th↗
arXiv2012

Generalized Rogers Ramanujan Identities from AGT Correspondence

AGT correspondence and its generalizations attracted a great deal of attention recently. In particular it was suggested that $U(r)$ instantons on $R^4/Z_p$ describe the conformal blocks of the coset ${\cal A}(r,p)=U(1)\times sl(p)_r\times {sl(r)_p\times sl(r)_n\over sl(r)_{n+p}}$, where $n$ is a parameter. Our purpose here is to describe Generalized Rogers Ramanujan (GRR) identities for these cosets, which expresses the characters as certain $q$ series. We propose that such identities exist for the coset ${\cal A}(r,p)$ for all positive integers $n$ and all $r$ and $p$. We treat here the case of $n=1$ and $r=2$, finding GRR identities for all the characters.

hep-th↗
arXiv2012

N=1 superconformal blocks with Ramond fields from AGT correspondence

We use AGT correspondence between N=2 SUSY Yang-Mills theory on ${\mathbb R}^4/{\mathbb Z}_2$ and two-dimensional CFT model with the algebra $ {\cal H} \oplus \hat{sl}(2)_2 \oplus \text{NSR}$ to obtain the explicit expressions for 4-point NSR conformal blocks including Ramond fields in terms of Nekrasov partition functions and correlation functions of $\hat{sl}(2)_2$ WZW model.

hep-th↗
arXiv2010

Bulk one-point function on disk in one-matrix model

We consider bulk correlation numbers on disk in one-matrix model. Using the recently found so-called resonance transformation from the KdV to the Liouville frame, we obtain an explicit expression for the bulk one-point function. The result is consistent with the form of FZZ one-point function in the boundary Liouville Field Theory.

hep-th↗
arXiv2005

Polyakov's String: Twenty Five Years After

An International Workshop dedicated to the anniversary of the Polyakov's String (of course today there is no need to remind the meaning and the role of this theory) was held in Chernogolovka in June 2005. Apart from the 25-th anniversary of the first appearance of the Polyakov's String theory, this conference, to our mind, might be also thought of as a 35 years from the discovery of the Conformal Invariance, 30 years of the Monopole and the Instantons and, finally, as the 20-th anniversary of the CFT. A case of mysterious coincidence, this year is also a jubilee of Sasha himself, whose contribution to the Theoretical Physics of 20-th century is far from being exhausted by the achievements listed above.

hep-th↗