Andrei Pronko | Searcharxiv

arXiv2004

On the partition function of the six-vertex model with domain wall boundary conditions

The six-vertex model on an $N\times N$ square lattice with domain wall boundary conditions is considered. A Fredholm determinant representation for the partition function of the model is given. The kernel of the corresponding integral operator is of the so-called integrable type, and involves classical orthogonal polynomials. From this representation, a ``reconstruction'' formula is proposed, which expresses the partition function as the trace of a suitably chosen quantum operator, in the spirit of corner transfer matrix and vertex operator approaches to integrable spin models.

math-ph↗

arXiv1994

Extended Chiral Transformations Including Diquark Fields as Parameters

We introduce extended chiral transformation, which depends both on pseudoscalar and diquark fields as parameters and determine its group structure. Assuming soft symmetry breaking in diquark sector, bosonisation of a quasi-Goldstone $ud$-diquark is performed. In the chiral limit the $ud$-diquark mass is defined by the gluon condensate, $m_{ud}\approx 300 MeV$. The diquark charge radius is $\langle r^2_{ud}\rangle^{1/2}\approx 0.5 fm$.

hep-ph↗