Publishing type：Research paper (scientific journal)  

We study how the symmetry operator of the axial U(1) non-invertible symmetry acts on the’t Hooft line operator in the U(1) gauge theory by employing the modified Villain-type lattice formulation. We model the axial anomaly by a compact scalar boson, the “QED axion”. For the gauge invariance, the simple’t Hooft line operator, which is defined by a line integral of the dual U(1) gauge potential, must be “dressed” by the scalar and U(1) gauge fields. A careful consideration on the basis of the anomalous Ward–Takahashi identity containing the’t Hooft operator with the dressing factor and a precise definition of the symmetry operator on the lattice shows that the symmetry operator leaves no effect when it sweeps out a’t Hooft loop operator. This result appears inequivalent with the phenomenon concluded in the continuum theory. In an appendix, we demonstrate that the half-space gauging of the magnetic ZN 1-form symmetry, when formulated in an appropriate lattice framework, leads to the same conclusion as above. A similar result is obtained for the axion string operator.

DOI： 10.1093/ptep/ptae093

Scopus

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DOI： 10.1093/ptep/ptae040

Publishing type：Research paper (scientific journal)  

arXiv

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We extend the definition of Lüscher’s lattice topological charge to the case of 4d SU(N) gauge fields coupled with ℤ N 2-form gauge fields. This result is achieved while maintaining the locality, the SU(N) gauge invariance, and ℤ N 1-form gauge invariance, and we find that the manifest 1-form gauge invariance plays the central role in our construction. This result gives the lattice regularized derivation of the mixed ’t Hooft anomaly in pure SU(N) Yang-Mills theory between its ℤ N 1-form symmetry and the θ periodicity.

DOI： 10.1007/JHEP08(2023)118

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DOI： 10.1093/ptep/ptad078

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DOI： 10.1093/ptep/ptad074

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DOI： 10.1093/ptep/ptad009

Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.22323/1.430.0177

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DOI： 10.1093/ptep/ptac047

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DOI： 10.1093/ptep/ptac003

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DOI： 10.1093/ptep/ptab096

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DOI： 10.1093/ptep/ptab100

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We theoretically clarify the functional form to be used in t → 0 extrapolation in the small flow time expansion method for the energy-momentum tensor (EMT), which facilitates lattice simulation of the EMT based on the gradient flow. We argue that in the t → 0 extrapolation analysis, lattice data should be fitted by a power function in g(μ(t)), the flow time dependent running coupling, where the power is determined by the perturbation order we consider. From actual lattice data, we confirm the validity of the extrapolation function. Using the new extrapolation function, we present updated lattice results for thermodynamics quantities in quenched QCD; our results are consistent with the previous study [T. Iritani et al., Prog. Theor. Exp. Phys. 2019, 023B02 (2019)] but we obtain smaller errors due to the reduction of systematic errors.

DOI： 10.1093/ptep/ptab068

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Abstract

We study latent heat and the pressure gap between the hot and cold phases at the first-order deconfining phase transition temperature of the SU(3) Yang–Mills theory. Performing simulations on lattices with various spatial volumes and lattice spacings, we calculate the gaps of the energy density and pressure using the small flow-time expansion (SF$t$X) method. We find that the latent heat $Delta epsilon$ in the continuum limit is $Delta epsilon /T^4 = 1.117 pm 0.040$ for the aspect ratio $N_s/N_t=8$ and $1.349 pm 0.038$ for $N_s/N_t=6$ at the transition temperature $T=T_c$. We also confirm that the pressure gap is consistent with zero, as expected from the dynamical balance of two phases at $T_c$. From hysteresis curves of the energy density near $T_c$, we show that the energy density in the (metastable) deconfined phase is sensitive to the spatial volume, while that in the confined phase is insensitive. Furthermore, we examine the effect of alternative procedures in the SF$t$X method—the order of the continuum and the vanishing flow-time extrapolations, and also the renormalization scale and higher-order corrections in the matching coefficients. We confirm that the final results are all very consistent with each other for these alternatives.

DOI： 10.1093/ptep/ptaa184

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DOI： 10.1093/ptep/ptaa184

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DOI： 10.1103/PhysRevD.102.059903

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DOI： 10.1093/ptep/ptaa096

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.102.034508

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DOI： 10.1103/PhysRevD.102.014510

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DOI： 10.1093/ptep/ptaa066

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DOI： 10.1093/ptep/ptaa002

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DOI： 10.1093/ptep/ptz157

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DOI： 10.1093/ptep/ptz147

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We propose a clear definition of the gluon condensate within the<br />
large-$eta_0$ approximation as an attempt toward a systematic argument on the<br />
gluon condensate. We define the gluon condensate such that it is free from a<br />
renormalon uncertainty, consistent with the renormalization scale independence<br />
of each term of the operator product expansion (OPE), and an identical object<br />
irrespective of observables. The renormalon uncertainty of<br />
$mathcal{O}(Lambda^4)$, which renders the gluon condensate ambiguous, is<br />
separated from a perturbative calculation by using a recently suggested<br />
analytic formulation. The renormalon uncertainty is absorbed into the gluon<br />
condensate in the OPE, which makes the gluon condensate free from the<br />
renormalon uncertainty. As a result, we can define the OPE in a renormalon-free<br />
way. Based on this renormalon-free OPE formula, we discuss numerical extraction<br />
of the gluon condensate using the lattice data of the energy density operator<br />
defined by the Yang--Mills gradient flow.

DOI： 10.1093/ptep/ptz100

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DOI： 10.1093/ptep/ptz020

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.99.059904

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Have computed the two-loop order (i.e., NNLO) coefficients in the gradient-flow representation of the energy-momentum tensor (EMT) in vector-like gauge theories. In this paper, we study the effect of the two-loop order corrections (and the three-loop order correction for the trace part of the EMT, which is available through the trace anomaly) on the lattice computation of thermodynamic quantities in quenched QCD. The use of the two-loop order coefficients generally reduces the t dependence of the expectation values of the EMT in the gradient-flow representation, where t is the flow time. With the use of the two-loop order coefficients, therefore, the t → 0 extrapolation becomes less sensitive to the fit function, the fit range, and the choice of the renormalization scale; the systematic error associated with these factors is considerably reduced.

DOI： 10.1093/ptep/ptz001

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In K. Hieda, A. Kasai, H. Makino, and H. Suzuki, Prog. Theor. Exp. Phys. 2017, 063B03 (2017), a properly normalized supercurrent in the four-dimensional (4D) N = 1 super Yang-Mills theory (SYM) that works within on-mass-shell correlation functions of gauge-invariant operators is expressed in a regularization-independent manner by employing the gradient flow. In the present paper, this construction is extended to the supercurrent in the 4D N = 2 SYM. The so-constructed supercurrent will be useful, for instance, for fine tuning of lattice parameters toward the supersymmetric continuum limit in future lattice simulations of the 4D N = 2 SYM.

DOI： 10.1093/ptep/pty117

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It is believed that the two-dimensional massless N = 2 Wess-Zumino model becomes the N = 2 superconformal field theory (SCFT) in the infrared (IR) limit. We examine this theoretical conjecture of the Landau-Ginzburg (LG) description of the N = 2 SCFT by numerical simulations on the basis of a supersymmetric-invariant momentum-cutoff regularization. We study a single supermultiplet with cubic and quartic superpotentials. From two-point correlation functions in the IR region, we measure the scaling dimension and the central charge, which are consistent with the conjectured LG description of the A2 and A3 minimal models, respectively. Our result supports the theoretical conjecture and, at the same time, indicates a possible computational method of correlation functions in the N = 2 SCFT from the LG description.

DOI： 10.1093/ptep/pty088

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DOI： 10.1093/ptep/pty073

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DOI： 10.1093/ptep/pty050

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DOI： 10.1051/epjconf/201817511014

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DOI： 10.1051/epjconf/201817511013

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DOI： 10.1051/epjconf/201817507023

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DOI： 10.1051/epjconf/201817507013

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DOI： 10.1093/ptep/ptx073

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© The Author(s) 2017. We study the one-loop effective action defined by the chiral overlap operator in the fourdimensional lattice formulation of chiral gauge theories by Grabowska and Kaplan. In the tree-level continuum limit, the left-handed component of the fermion is coupled only to the original gauge field A, while the right-handed one is coupled only to A∗, which is given by the gradient flow of A with infinite flow time. In this paper, we show that the continuum limit of the one-loop effective action contains local interaction terms between A and A∗, which do not generally vanish even if the gauge representation of the fermion is anomaly free.We argue that the presence of such interaction terms can be regarded as undesired gauge symmetry-breaking effects in the formulation.

DOI： 10.1093/ptep/ptx085

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DOI： 10.1016/j.nuclphysb.2017.02.017

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DOI： 10.1103/PhysRevD.95.054502

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DOI： 10.1103/PhysRevD.94.114512

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DOI： 10.1142/S021773231650214X

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DOI： 10.1093/ptep/ptw167

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Background field method in the gradient flow
The Yang--Mills gradient flow and its extension to the fermion field provide
a very general method to obtain renormalized observables in gauge theory. The
method is applicable also with non-perturbative regularization such as lattice.
The gradient flow thus offers useful probes to study non-perturbative dynamics
of gauge theory. In this work, aiming at possible simplification in
perturbative calculations associated with the gradient flow, a modification of
the gauge-fixed version of the flow equation, which preserves gauge covariance
under the background gauge transformation, is proposed. This formulation allows
for example a very quick one-loop calculation of the small flow time expansion
of a composite operator that is relevant to the construction of a lattice
energy--momentum tensor. Some details of the calculation, which have not been
given elsewhere, are presented.

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.92.085020

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DOI： 10.1103/PhysRevD.92.085020

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DOI： 10.1093/ptep/ptv139

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DOI： 10.1103/PhysRevD.92.059902

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DOI： 10.1103/PhysRevD.92.059902

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DOI： 10.1103/PhysRevD.91.065010

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DOI： 10.1093/ptep/ptv028

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DOI： 10.1103/PhysRevD.90.011501

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevD.90.011501

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DOI： 10.1016/j.nuclphysb.2013.09.005

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DOI： 10.1016/j.nuclphysb.2012.11.023

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DOI： 10.1016/j.physletb.2013.01.028

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DOI： 10.1016/j.nuclphysb.2012.04.008

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DOI： 10.1016/j.nuclphysb.2011.09.007

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DOI： 10.1016/j.physletb.2010.12.012

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DOI： 10.1016/j.physletb.2010.01.022

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DOI： 10.1016/j.physletb.2009.11.028

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DOI： 10.1016/j.nuclphysb.2009.05.012

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DOI： 10.1016/j.nuclphysb.2008.11.021

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DOI： 10.1016/j.physletb.2009.01.039

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DOI： 10.1103/PhysRevD.77.091502

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DOI： 10.1143/PTP.119.797

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DOI： 10.1088/1126-6708/2007/10/018

Language：English   Publishing type：Research paper (scientific journal)  

Language：Others  

Numerical results of two-dimensional N=(2,2) super Yang-Mills theory
We report the results of a numerical simulation of a lattice formulation of
the two-dimensional N=(2,2) super Yang-Mills theory proposed by Suzuki and
Taniguchi. We measure the 1-point functions and 2-point functions. The scenario
is that only tuning of the scalar mass to a specific value gives a
supersymmetric continuum limit. Our results are consistent with this scenario
although conclusive results on the restoration of supersymmetry have not been
obtained.

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We carry out preliminary numerical study of Sugino's lattice formulation [1, 2] of the two-dimensional ≤ (2,2) super Yang-Mills theory (2d ≤ (2,2) SYM) with the gauge group SU(2). The effect of dynamical fermions is included by re-weighting a quenched ensemble by the pfaffian factor. It appears that the complex phase of the pfaffian due to lattice artifacts and flat directions of the classical potential are not problematic in Monte Carlo simulation. Various one-point supersymmetric Ward-Takahashi (WT) identities are examined for lattice spacings up to a ≤ 0.5/g with the fixed physical lattice size L ≤ 4.0/g, where g denotes the gauge coupling constant in two dimensions. WT identities implied by an exact fermionic symmetry of the formulation are confirmed in fair accuracy and, for most of these identities, the quantum effect of dynamical fermions is clearly observed. For WT identities expected only in the continuum limit, the results seem to be consistent with the behavior expected from supersymmetry, although we do not see clear distintion from the quenched simulation. We measure also the expectation values of renormalized gauge-invariant bi-linear operators of scalar fields. © SISSA 2007.

DOI： 10.1088/1126-6708/2007/09/052

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.116.1117

Language：Others  

Overlap Fermion in External Gravity
On a lattice, we construct an overlap Dirac operator which describes the
propagation of a Dirac fermion in external gravity. The local Lorentz symmetry
is manifestly realized as a lattice gauge symmetry, while the general
coordinate invariance is expected to be restored only in the continuum limit.
The lattice index density in the presence of a gravitational field is
calculated.

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physe.2006.03.141

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.116.197

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DOI： 10.1143/PTP.115.1129

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DOI： 10.1143/PTP.115.467

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The N ≤ (2,2) extended super Yang-Mills theory in 2 dimensions is formulated on the lattice as a dimensional reduction of a 4 dimensional lattice gauge theory. We use the plaquette action for a bosonic sector and the Wilson- or the overlap-Dirac operator for a fermion sector. The fermion determinant is real and, moreover, when the overlap-Dirac operator is used, semi-positive definite. The flat directions in the target theory become compact and present no subtlety for a numerical integration along these directions. Any exact supersymmetry does not exist in our lattice formulation; nevertheless we argue that one-loop calculable and finite mass counter terms ensure a supersymmetric continuum limit to all orders of perturbation theory. © SISSA 2005.

DOI： 10.1088/1126-6708/2005/10/082

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/JPSJ.74.1674

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DOI： 10.1088/1126-6708/2005/01/051

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A local formulation of lattice Wess-Zumino model with exact $U(1)_R$ symmetry
A lattice Wess-Zumino model is formulated on the basis of Ginsparg-Wilson
fermions. In perturbation theory, our formulation is equivalent to the
formulation by Fujikawa and Ishibashi and by Fujikawa. Our formulation is,
however, free from a singular nature of the latter formulation due to an
additional auxiliary chiral supermultiplet on a lattice. The model posssesses
an exact $U(1)_R$ symmetry as a supersymmetric counterpart of the L"uscher
lattice chiral $U(1)$ symmetry. A restration of the supersymmetric
Ward-Takahashi identity in the continuum limit is analyzed in renormalized
perturbation theory. In the one-loop level, a supersymmetric continuum limit is
ensured by suitably adjusting a coefficient of a single local term $ ilde
F^* ilde F$. The non-renormalization theorem holds to this order of
perturbation theory. In higher orders, on the other hand, coefficents of local
terms with dimension $leq4$ that are consistent with the $U(1)_R$ symmetry
have to be adjusted for a supersymmetric continuum limit. The origin of this
complexicity in higher-order loops is clarified on the basis of the Reisz power
counting theorem. Therefore, from a view point of supersymmetry, the present
formulation is not quite better than a lattice Wess-Zumino model formulated by
using Wilson fermions, although a number of coefficients which require
adjustment is much less due to the exact $U(1)_R$ symmetry. We also comment on
an exact non-linear fermionic symmetry which corresponds to the one studied by
Bonini and Feo; an existence of this exact symmetry itself does not imply a
restoration of supersymmetry in the continuum limit without any adjustment of
parameters.

DOI： 10.1088/1126-6708/2005/02/012

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Anomalous gauge theories revisited
A possible formulation of chiral gauge theories with an anomalous fermion
content is re-examined in light of the lattice framework based on the
Ginsparg-Wilson relation. It is shown that the fermion sector of a wide class
of anomalous non-abelian theories cannot consistently be formulated within this
lattice framework. In particular, in 4 dimension, {it all} anomalous
non-abelian theories are included in this class. Anomalous abelian chiral gauge
theories cannot be formulated with compact $U(1)$ link variables, while a
non-compact formulation is possible at least for the vacuum sector in the space
of lattice gauge fields. Our conclusion is not applied to effective low-energy
theories with an anomalous fermion content which are obtained from an
underlying anomaly-free theory by sending the mass of some of fermions to
infinity. For theories with an anomalous fermion content in which the anomaly
is cancelled by the Green-Schwarz mechanism, a possibility of a consistent
lattice formulation is not clear.

DOI： 10.1088/1126-6708/2005/01/051

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.112.855

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DOI： 10.1016/j.physrep.2004.05.002

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DOI： 10.1093/acprof:oso/9780198529132.001.0001

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1126-6708/2004/07/038

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Majorana and Majorana-Weyl fermions in lattice gauge theory
In various dimensional Euclidean lattice gauge theories, we examine a
compatibility of the Majorana decomposition and the charge conjugation property
of lattice Dirac operators. In $8n$ and $1+8n$ dimensions, we find a difficulty
to decompose a classical lattice action of the Dirac fermion into a system of
the Majorana fermion and thus to obtain a factorized form of the Dirac
determinant. Similarly, in $2+8n$ dimensions, there is a difficulty to
decompose a classical lattice action of the Weyl fermion into a system of the
Majorana--Weyl fermion and thus to obtain a factrized form of the Weyl
determinant. Prescriptions based on the overlap formalism do not remove these
difficulties. We argue that these difficulties are reflections of the global
gauge anomaly associated to the real Weyl fermion in $8n$ dimensions. For this
reason (besides other well-known reasons), a lattice formulation of the N=1
super Yang--Mills theory in these dimensions is expected to be extremely
difficult to find.

DOI： 10.1088/1126-6708/2004/07/038

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0920-5632(03)02623-9

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1126-6708/2003/09/015

Language：Others  

Wess-Zumino-Witten term on the lattice
We construct the Wess-Zumino-Witten (WZW) term in lattice gauge theory by
using a Dirac operator which obeys the Ginsparg-Wilson relation. Topological
properties of the WZW term known in the continuum are reproduced on the lattice
as a consequence of a non-trivial topological structure of the space of
admissible lattice gauge fields. In the course of this analysis, we observe
that the gauge anomaly generally implies that there is no basis of a Weyl
fermion which leads to a single-valued expectation value in the fermion sector.
The lattice Witten term, which carries information of a gauge path along which
the gauge anomaly is integrated, is separated from the WZW term and the
multivaluedness of the Witten term is shown to be related to the homotopy group
$pi_{2n+1}(G)$. We also discuss the global $SU(2)$ anomaly on the basis of
the WZW term.

DOI： 10.1088/1126-6708/2003/09/015

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1126-6708/2003/05/042

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0920-5632(03)80466-8

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DOI： 10.1016/S0550-3213(02)00812-X

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1126-6708/2002/09/025

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1126-6708/2002/09/032

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Axial anomaly with the overlap-Dirac operator in arbitrary dimensions
We evaluate for arbitrary even dimensions the classical continuum limit of
the lattice axial anomaly defined by the overlap-Dirac operator. Our
calculational scheme is simple and systematic. In particular, a powerful
topological argument is utilized to determine the value of a lattice integral
involved in the calculation. When the Dirac operator is free of species
doubling, the classical continuum limit of the axial anomaly in various
dimensions is combined into a form of the Chern character, as expected.

DOI： 10.1088/1126-6708/2002/09/025

Language：Others  

Chiral anomalies in the reduced model
On the basis of an observation due to Kiskis, Narayanan and Neuberger, we
show that there is a remnant of chiral anomalies in the reduced model when a
Dirac operator which obeys the Ginsparg-Wilson relation is employed for the
fermion sector. We consider fermions belonging to the fundamental
representation of the gauge group U(N) or SU(N). For vector-like theories, we
determine a general form of the axial anomaly or the topological charge within
a framework of a U(1) embedding. For chiral gauge theories with the gauge group
U(N), a remnant of gauge anomaly emerges as an obstruction to a smooth fermion
integration measure. The pure gauge action of gauge-field configurations which
cause these non-trivial phenomena always diverges in the 't Hooft $N oinfty$
limit when d>2.

DOI： 10.1088/1126-6708/2002/09/032

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0370-2693(02)01936-6

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1126-6708/2002/04/046

Language：Others  

CP breaking in lattice chiral gauge theories
The CP symmetry is not manifestly implemented for the local and doubler-free
Ginsparg-Wilson operator in lattice chiral gauge theory. We precisely identify
where the effects of this CP breaking appear. We show that they appear in: (I)
Overall constant phase of the fermion generating functional. (II) Overall
constant coefficient of the fermion generating functional. (III) Fermion
propagator appearing in external fermion lines and the propagator connected to
Yukawa vertices. The first effect appears from the transformation of the path
integral measure and it is absorbed into a suitable definition of the constant
phase factor for each topological sector; in this sense there appears no ``CP
anomaly''. The second constant arises from the explicit breaking in the action
and it is absorbed by the suitable weights with which topological sectors are
summed. The last one in the propagator is inherent to this formulation and
cannot be avoided by a mere modification of the projection operator, for
example, in the framework of the Ginsparg-Wilson operator. This breaking
emerges as an (almost) contact term in the propagator when the Higgs field,
which is treated perturbatively, has no vacuum expectation value. In the
presence of the vacuum expectation value, however, a completely new situation
arises and the breaking becomes intrinsically non-local, though this breaking
may still be removed in a suitable continuum limit. This non-local CP breaking
is expected to persist for a non-perturbative treatment of the Higgs coupling.

DOI： 10.1088/1126-6708/2002/04/046

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0920-5632(01)01837-0

Language：Others  

On the lattice construction of electroweak gauge theory
Based on the Ginsparg-Wilson relation, a gauge invariant formulation of
electroweak SU(2)xU(1) gauge theory on the lattice is considered. If the
hypercharge gauge coupling is turned off in the vacuum sector of the U(1) gauge
fields, the theory consists of four left-handed SU(2) doublets and it is
possible, as in vector-like theories, to make the fermion measure defined
globally in all topological sectors of SU(2). We then try to incorporate U(1)
gauge field, following L"uscher's reconstruction theorem. The global
integrability condition is proved for ``gauge loops'' in the space of the U(1)
gauge fields with arbitrary SU(2) gauge field fixed in the background. For
``non-gauge loops'', however, the proof is given so far only for the classical
SU(2) instanton backgrounds.

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.105.789

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0550-3213(00)00676-3

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Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0550-3213(00)00408-9

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Real Representation in Chiral Gauge Theories on the Lattice
The Weyl fermion belonging to the real representation of the gauge group
provides a simple illustrative example for L"uscher's gauge-invariant lattice
formulation of chiral gauge theories. We can explicitly construct the fermion
integration measure globally over the gauge-field configuration space in the
arbitrary topological sector; there is no global obstruction corresponding to
the Witten anomaly. It is shown that this Weyl formulation is equivalent to a
lattice formulation based on the Majorana (left--right-symmetric) fermion, in
which the fermion partition function is given by the Pfaffian with a definite
sign, up to physically irrelevant contact terms. This observation suggests a
natural relative normalization of the fermion measure in different topological
sectors for the Weyl fermion belonging to the complex representation.

DOI： 10.1088/1126-6708/2000/10/039

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0370-2693(00)00920-5

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0550-3213(99)00706-3

Language：Others   Publishing type：Research paper (scientific journal)  

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.102.141

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.101.1147

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.100.1033

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1142/S0217732398002710

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.100.627

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1143/PTP.98.463

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0370-2693(97)00368-7

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0370-2693(96)00648-X

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/aphy.1996.0066

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0375-9601(96)00243-5

Language：Others   Publishing type：Research paper (scientific journal)  

Using a simple solvable model, i.e., Higgs--Yukawa system with an infinite<br />
number of flavors, we explicitly demonstrate how a dimensional continuation of<br />
the $eta$ function in two dimensional MS scheme {it fails/} to reproduce<br />
the correct behavior of the $eta$ function in four dimensions. The mapping<br />
between coupling constants in two dimensional MS scheme and a conventional<br />
scheme in the cutoff regularization, in which the dimensional continuation of<br />
the $eta$ function is smooth, becomes singular when the dimension of<br />
spacetime approaches to four. The existence of a non-trivial fixed point in<br />
$2+epsilon$ dimensions continued to four dimensions $epsilon o2$ in the two<br />
dimensional MS scheme is spurious and the asymptotic safety cannot be imposed<br />
to this model in four dimensions.

DOI： 10.1143/PTP.95.985

Language：Others   Publishing type：Research paper (scientific journal)  

Super-Virasoro Anomaly, Super-Weyl Anomaly and the Super-Liouville Action for 2D Supergravity
The relation between super-Virasoro anomaly and super-Weyl anomaly in $N=1$<br />
NSR superstring coupled with 2D supergravity is investigated from canonical<br />
theoretical view point. The WZW action canceling the super-Virasoro anomaly is<br />
explicitly constructed. It is super-Weyl invariant but nonlocal functional of<br />
2D supergravity. The nonlocality can be remedied by the super-Liouvlle action,<br />
which in turn recovers the super-Weyl anomaly. The final gravitational<br />
effective action turns out to be local but noncovariant super-Liouville action,<br />
describing the dynamical behavior of the super-Liouville fields. The BRST<br />
invariance of this approach is examined in the superconformal gauge and in the<br />
light-cone gauge.

DOI： 10.1006/aphy.1996.5643

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/aphy.1995.1059

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1142/S0217751X9400011X

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0550-3213(93)90241-G

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0370-2693(92)91397-R

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0370-2693(92)90191-6

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0550-3213(91)90272-Y

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0550-3213(90)90106-N

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0370-2693(89)91712-7

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0370-2693(88)91761-3

Event date： 2022.4

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.4

Language：Japanese  

Venue：オンライン   Country：Japan  

Event date： 2022.4

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.4

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.4

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.4

Language：Japanese  

Venue：オンライン   Country：Japan  

Event date： 2022.4

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.4

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.4

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2020.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2018.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：品川グランドセントラルタワー   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.8

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2017.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2016.12

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.7

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.7

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2015.3

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：佐賀大学   Country：Japan  

Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：慶應義塾大学   Country：Japan  

Event date： 2014.1

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：高エネルギー加速器研究機構   Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Language：Japanese  

Country：Japan  

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Language：Japanese  

Country：Japan  

ここ10年ほどの間に,格子ゲージ理論におけるカイラル対称性とカイラルフェルミオンに対する我々の認識は一変した.ベクトル型の格子ゲージ理論で厳密なカイラル対称性を保つ定式化が発見され,量子色力学(QCD)の数値シミュレーションへの応用が本格化している.また,従来,カイラルなゲージ理論は非摂動論的に定義できないのでは,と思われていたふしがあるが,現在では,構成論的定式化があってもおかしくない,というのが大方の見方であると思われる.ここでは,格子ゲージ理論におけるカイラル対称性の実現と題して,最近までの理論的進展について解説する.

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Language：Japanese  

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Language：Japanese  

Language：Japanese  

DOI： 10.11316/butsuri.73.3_148

Language：Japanese  

Language：Japanese  

Language：Japanese  

Language：Others  

A dilaton-pion mass relation
Recently, Golterman and Shamir presented an effective field theory which is
supposed to describe the low-energy physics of the pion and the dilaton in an
&#36;SU(N_c)&#36; gauge theory with &#36;N_f&#36; Dirac fermions in the fundamental
representation. By employing this formulation with a slight but important
modification, we derive a relation between the dilaton mass squared~&#36;m_ au^2&#36;,
with and without the fermion mass~&#36;m&#36;, and the pion mass squared~&#36;m_pi^2&#36; to
the leading order of the chiral logarithm. This is analogous to a similar
relation obtained by Matsuzaki and~Yamawaki on the basis of a somewhat
different low-energy effective field theory. Our relation reads
&#36;m_ au^2=m_ au^2|_{m=0}+KN_fhat{f}_pi^2m_pi^2/(2hat{f}_ au^2)+O(m_pi^4ln
m_pi^2)&#36; with~&#36;K=9&#36;, where &#36;hat{f}_pi&#36; and~&#36;hat{f}_ au&#36; are decay
constants of the pion and the dilaton, respectively. This mass relation differs
from the one derived by Matsuzaki and~Yamawaki on the points that
&#36;K=(3-gamma_m)(1+gamma_m)&#36;, where &#36;gamma_m&#36; is the mass anomalous dimension,
and the leading chiral logarithm correction is~&#36;O(m_pi^2ln m_pi^2)&#36;.
For~&#36;gamma_msim1&#36;, the value of the decay constant~&#36;hat{f}_ au&#36; estimated
from our mass relation becomes &#36;sim50&#37;&#36; larger than &#36;hat{f}_ au&#36; estimated
from the relation of Matsuzaki and~Yamawaki.

Language：Japanese  

DOI： 10.11316/butsuri.71.6_399

Language：Japanese  

Language：Japanese  

Language：Others  

Perturbative spectrum of a Yukawa-Higgs model with Ginsparg-Wilson fermions
A Yukawa-Higgs model with Ginsparg-Wilson (GW) fermions, proposed recently by
Bhattacharya, Martin and Poppitz as a possible lattice formulation of chiral
gauge theories, is studied. A simple argument shows that the gauge boson always
acquires mass by the St"uckelberg (or, in a broad sense, Higgs) mechanism,
regardless of strength of interactions. The gauge symmetry is spontaneously
broken. When the gauge coupling constant is small, the physical spectrum of the
model consists of massless fermions, massive fermions and emph{massive} vector
bosons.

Language：Japanese  

Language：English  

Language：Japanese  

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：7

Type：Competition, symposium, etc. 

Type：Scientific advice/Review 

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：4

Type：Academic society, research group, etc. 

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：5

Type：Competition, symposium, etc. 

Type：Scientific advice/Review 

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：4

Type：Scientific advice/Review 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：7

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：2

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：3