arXiv subjects

Kohei Iwaki

Publications and source records attributed to Kohei Iwaki.

22 records · Page 2Linked to original sources

arXiv2014

Exact WKB analysis and cluster algebras

We develop the mutation theory in the exact WKB analysis using the framework of cluster algebras. Under a continuous deformation of the potential of the Schrödinger equation on a compact Riemann surface, the Stokes graph may change the topology. We call this phenomenon the mutation of Stokes graphs. Along the mutation of Stokes graphs, the Voros symbols, which are monodromy data of the equation, also mutate due to the Stokes phenomenon. We show that the Voros symbols mutate as variables of a cluster algebra with surface realization. As an application, we obtain the identities of Stokes automorphisms associated with periods of cluster algebras. The paper also includes an extensive introduction of the exact WKB analysis and the surface realization of cluster algebras for nonexperts.

math.CA↗

arXiv2013

Stokes Matrices for the Quantum Cohomologies of Orbifold Projective Lines

We prove the Dubrovin's conjecture for the Stokes matrices for the quantum cohomology of orbifold projective lines. The conjecture states that the Stokes matrix of the first structure connection of the Frobenius manifold constructed from the Gromov-Witten theory coincides with the Euler matrix of a full exceptional collection of the bounded derived category of the coherent sheaves. Our proof is based on the homological mirror symmetry, primitive forms of affine cusp polynomials and the Picard-Lefschetz theory.

math.AG↗

arXiv2013

Voros coefficients of the third Painelv'e equation and parametric Stokes phenomena

We compute all Voros coefficients of the third Painleve equation of the type D6 (in the sense of [OKSO]) and discuss the parametric Stokes phenomena occurring to formal transseries solutions. We derive connection formulas for parametric Stokes phenomena under an assumption for Borel summability of transseries solutions. Furthermore, we also compute the Voros coefficient of the degenerate third Painleve equation of the type D7 in Appendix D.

math.CA↗

arXiv2011

Parametric Stokes phenomenon for the second Painlevé equation with a large parameter

The second Painlevé equation with a large parameter ($P_{II}$) is analyzed by using the exact WKB analysis. The purpose of this study is to investigate the problem of the degeneration of $P$-Stokes geometry of ($P_{II}$), which relates to a kind of Stokes phenomena for asymptotic (formal) solutions of ($P_{II}$). We call this Stokes phenomenon a "parametric Stokes phenomenon". We formulate the connection formula for this Stokes phenomenon, and confirm it in two ways: the first one is by computing the "Voros coefficient" of ($P_{II}$), and the second one is by using the isomonodromic deformation theory. Our main claim is that the connection formulas derived by these two completely different methods coincide.

math.CA↗