arXiv subjects

Takao Suyama

Publications and source records attributed to Takao Suyama.

At least 19 recordsLinked to original sources

arXiv2025

Differential Equations for Wilson Loops in ABJM Theory

We derive a system of differential equations which are satisfied by the vevs of BPS Wilson loops and 't Hooft coupling of ABJM theory. They are Picard-Fuchs equations of an algebraic curve defined by the derivative of the planar resolvent of the corresponding matrix model. The weak and strong coupling behaviors can be reproduced by their local solutions around regular singularities. We also obtain a recursion relation which can be used to determine the planar vevs of BPS Wilson loops in arbitrary representations.

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arXiv2023

Solvable limit of ETH matrix model for double-scaled SYK

We study the two-matrix model for double-scaled SYK model, called ETH matrix model introduced by Jafferis et al [arXiv:2209.02131]. If we set the parameters $q_A,q_B$ of this model to zero, the potential of this two-matrix model is given by the Gaussian terms and the $q$-commutator squared interaction. We find that this model is solvable in the large $N$ limit and we explicitly construct the planar one- and two-point function of resolvents in terms of elliptic functions.

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arXiv2023

Stringy Threshold Corrections in D-brane Systems

We investigate string amplitudes by using the partial modular transformation which we introduced in our previous works. This enables us to extract stringy threshold corrections from the full string amplitudes and interpret them in terms of the Wilsonian effective field theory in a natural way. We calculate mass shifts and wave function renormalizations for massless scalar fields on brane-antibrane systems. We find that the mass shift can be exponentially small and negative. We also propose a strategy for realizing a hierarchical mass spectrum on D-branes.

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arXiv2021

Gauge Symmetry Restoration by Higgs Condensation in Flux Compactifications on Coset Spaces

Extra-dimensional components of gauge fields in higher-dimensional gauge theories will play a role of the Higgs field and become tachyonic after Kaluza-Klein compactifications on internal spaces with (topologically nontrivial) gauge field backgrounds. Its condensation is then expected to break gauge symmetries spontaneously. But, contrary to the expectation, some models exhibit restoration of gauge symmetries. In this paper, by considering all the massive Kaluza-Klein excitations of gauge fields, we explicitly show that some of them indeed become massless at the minimum of the Higgs potential and restore (a part of) the gauge symmetries which are broken by gauge field backgrounds. We particularly consider compactifications on $S^2$ with monopole-like fluxes and also on $\mathbb{CP}^2$ with instanton and monopole-like fluxes. In some cases, the gauge symmetry is fully restored, as argued in previous literature. In other cases, there is a stable vacuum with a partial restoration of the gauge symmetry after Higgs condensation. Topological structure of the gauge field configurations prevent the gauge symmetries to be restored.

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arXiv2020

More on Effective Potentials for Revolving D-Branes

We continue to investigate the effective potential between a pair of D$p$-branes revolving around each other by using the technique of ${\it partial\ modular\ transformation}$ developed in our previous work. We determine the shape of the potential for general $p$ for a wide range of regions interpolating smaller and larger distances than the string scale $l_s$. We also discuss the backreaction of the D-brane system to the space-time metric and the validity of our calculations.

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arXiv2019

Dynamics of Revolving D-Branes at Short Distances

We study the behavior of the effective potential between revolving D$p$-branes at all ranges of the distance $r$, interpolating $r \gg l_s$ and $r \ll l_s$ ($l_s$ is the string length). Since the one-loop open string amplitude cannot be calculated exactly, we instead employ an efficient method of $\it{ partial\ modular\ transformation}$. The method is to perform the modular transformation partially in the moduli parameter and rewrite the amplitude into a sum of contributions from both of the open and closed string massless modes. It is nevertheless free from the double counting and can approximate the open string amplitudes with less than $3\%$ accuracy. From the D-brane effective field theory point of view, this amounts to calculating the one-loop threshold corrections of infinitely many open string massive modes. We show that threshold corrections to the $ω^2 r^2$ term of the moduli field $r$ cancel among them, where $ω$ is the angular frequency of the revolution and sets the scale of supersymmetry breaking. This cancellation suggests a possibility to solve the hierarchy problem of the Higgs mass in high scale supersymmetry breaking models.

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arXiv2019

Effective Potential for Revolving D-branes

We quantize an open string stretched between D0-branes revolving around each other. The worldsheet theory is analyzed in a rotating coordinate system in which the worldsheet fields obey simple boundary conditions, but instead the worldsheet Lagrangian becomes nonlinear. We quantize the system perturbatively with respect to the velocity of the D-branes and determine the one-loop partition function of the open string, from which we extract the short-distance behavior of the effective potential for the revolving D0-branes. It is compared with the calculation of the partition function of open strings between D0-branes moving at a constant relative velocity.

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arXiv2019

Linear Chern-Simons-matter Theories in the Planar Limit

We study ${\cal N}=3$ linear Chern-Simons-matter theories in the planar limit. The matter content of the theory is depicted by a linear-shape diagram with $n$ nodes and $n-1$ links for any $n$. The free energy and the vevs of BPS Wilson loops are given in terms of a single 1-form on $\mathbb{CP}^1$ which can be determined explicitly for all linear theories. The analytic structure of the vevs of the Wilson loops is investigated in detail for $n=1$ and $n=2$. The addition of fundamental matters is also discussed.

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arXiv2018

Secular Terms in Dyson Series to All-Orders of Perturbation

In classical and quantum systems, perturbation of an evolution equation is often invalidated by secular terms which diverge at late times. The diverging behavior of evolution can be remedied by various techniques of resumma- tion such as renormalization group or multi-scale analysis. In this paper, we prove that, in a generic quantum mechanical system, secular terms can be systematically removed to all orders in the Dyson series by the method of improved (renormalized) perturbation. A recurrence relation to provide an explicit method to remove the secular terms is given. As a byproduct, we give a simple method to obtain energy eigenvalues and decay rates to all orders of perturbation.

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arXiv2017

$θ=π$ in $SU(N)/\mathbb{Z}_N$ gauge theories

In $SU(N)$ gauge theory, it is argued recently that there exists a "mixed anomaly" between the CP symmetry and the 1-form $\mathbb{Z}_N$ symmetry at $θ=π$, and the anomaly matching requires CP to be spontaneously broken at $θ=π$ if the system is in the confining phase. In this paper, we elaborate on this discussion by examining the large volume behavior of the partition functions of the $SU(N)/\mathbb{Z}_N$ theory on $T^4$ a la 't Hooft. The periodicity of the partition function in $θ$, which is not $2π$ due to fractional instanton numbers, suggests the presence of a phase transition at $θ=π$. We propose lattice simulations to study the distribution of the instanton number in $SU(N)/\mathbb{Z}_N$ theories. A characteristic shape of the distribution is predicted when the system is in the confining phase. The measurements of the distribution may be useful in understanding the phase structure of the theory.

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arXiv2017

Strong Coupling Limit of A Family of Chern-Simons-matter Theories

We investigate the strong coupling limit of a family of Chern-Simons-matter theories in the planar limit. The family consists of ${\cal N}=3$ theories with the gauge group ${\rm U}(N_1)_{k_1}\times{\rm U}(N_2)_{k_2}$ coupled to $n$ bi-fundamental hypermultiplets. All observables which can be determined from the planar resolvent turn out to have finite limits in the large 't Hooft coupling limit. Possible gravity duals are briefly discussed. We observe that Kac-Moody algebras govern the structure of the planar spectral curves of the theories.

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arXiv2016

Notes on Planar Resolvents of Chern-Simons-matter Matrix Models

We revisit planar resolvents of matrix models corresponding to ${\cal N}\ge3$ Chern-Simons-matter theories with the gauge groups of the form ${\rm U}(N_1)\times{\rm U}(N_2)$ coupled to any number of bi-fundamental hypermultiplets. We find that the derivative of a suitably defined planar resolvent can be written explicitly. From this resolvent, we derive the explicit formula for (a linear combination of) the vevs of BPS Wilson loops.

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arXiv2016

Cubic constraints for the resolvents of the ABJM matrix model and its cousins

A set of Schwinger-Dyson equations forming constraints for at most three resolvent functions are considered for a class of Chern-Simons matter matrix models with two nodes labelled by a non-vanishing number $n$. The two cases $n=2$ and $n= -2$ label respectively the ABJM matrix model, which is the hyperbolic lift of the affine $A_1^{(1)}$ quiver matrix model, and the lens space matrix model. In the planar limit, we derive two cubic loop equations for the two planar resolvents. One of these reduces to the quadratic one when $n = \pm 2$.

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arXiv2016

Instanton Effects in Orientifold ABJM Theory

We investigate another supersymmetric Chern-Simons theory called the orientifold ABJM theory, which replaces the unitary supergroup structure of the ABJM theory with an orthosymplectic one. Its non-perturbative structure is completely clarified by considering the duplication of the quiver.

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arXiv2016

Orthosymplectic Chern-Simons Matrix Model and Chirality Projection

Recently it was found that the density matrix for a certain orthosymplectic Chern-Simons theory matches with that for the ABJM theory with the odd chiral projection. We prove this fact for a general case with the inclusion of fractional branes. We also identify the first few diagonal Gopakumar-Vafa invariants for the grand potential constructed from the chirally projected density matrix.

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arXiv2014

Supersymmetry Breaking and Planar Free Energy in Chern-Simons-matter Theories

We investigate a relation between zeros of the partition function and supersymmetry breaking, conjectured by Morita and Niarchos, for a family of Chern-Simons-matter theories. We analyze the analytic structure of the free energy in the large $N$ limit derived from the resolvent of the corresponding matrix model. We find that a branch point exists at the value of the 't Hooft coupling above which supersymmetry is known to be broken, confirming the conjecture.

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arXiv2013

A Systematic Study on Matrix Models for Chern-Simons-matter Theories

We investigate the planar solution of matrix models derived from various Chern-Simons-matter theories compatible with the planar limit. The saddle-point equations for most of such theories can be solved in a systematic way. A relation to Fuchsian systems play an important role in obtaining the planar resolvents. For those theories, the eigenvalue distribution is found to be confined in a bounded region even when the 't Hooft couplings become large. As a result, the vevs of Wilson loops are bounded in the large 't Hooft coupling limit. This implies that many of Chern-Simons-matter theories have quite different properties from ABJM theory. If the gauge group is of the form ${\rm U}(N_1)_{k_1}\times{\rm U}(N_2)_{k_2}$, then the resolvents can be obtained in a more explicit form than in the general cases.

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arXiv2012

On Large N Solution of N=3 Chern-Simons-adjoint Theories

The planar resolvent for N=3 U(N)_k Chern-Simons theory coupled to an arbitrary number of adjoint matters is determined. Analytic continuation of the 't Hooft coupling t is analyzed. The eigenvalue distribution turns out to be confined in a finite region even for a large t. The vev of a Wilson loop does not exhibit an exponential growth although such a behavior would be expected for theories with classical gravity duals.

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