arXiv subjects

Jaemo Park

Publications and source records attributed to Jaemo Park.

At least 73 records · Page 4Linked to original sources

arXiv2003

Covariant Description of D-branes in IIA Plane-Wave Background

We work out boundary conditions for the covariant open string in the type IIA plane wave background, which corresponds to the D-branes in the type IIA theory. We use the kappa symmetric string action and see what kind of boundary conditions should be imposed to retain kappa symmetry. We find half BPS as well as quarter BPS branes and the analysis agrees with the previous work in the light cone gauge if the result is available. Finally we find that D0-brane is non-supersymmetric.

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arXiv2003

Chiral primary cubic interactions from pp-wave supergravity

We explicitly construct cubic interaction light-cone Hamiltonian for the chiral primary system involving the metric fields and the self-dual four-form fields in the IIB pp-wave supergravity. The background fields representing pp-waves exhibit SO(4)*SO(4)*Z_2 invariance. It turns out that the interaction Hamiltonian is precisely the same as that for the dilaton-axion system, except for the fact that the chiral primary system fields have the opposite parity to that of the dilaton-axion fields under the Z_2 transformation that exchanges two SO(4)'s.

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arXiv2002

PP-wave/Yang-Mills Correspondence: An Explicit Check

We present an explicit evidence that shows the correspondence between the type IIB supergravity in the pp-wave background and its dual supersymmetric Yang-Mills theory at the interaction level. We first construct the cubic term of the light-cone interaction Hamiltonian for the dilaton-axion sector of the supergravity. Our result agrees with the corresponding part of the light-cone string field theory (SFT) and furthermore fixes its previously undetermined $p^+$-dependent normalization. Adopting thus fixed light-cone SFT, we compute the matrix elements of light-cone Hamiltonian involving three chiral primary states and find an agreement with a prediction from the dual Yang-Mills theory.

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arXiv2002

Geometric Transition versus Cascading Solution

We study Vafa's geometric transition and Klebanov - Strassler solution from various points of view in M-theory. In terms of brane configurations, we show the detailed equivalences between the two models. In some limits, both models have an alternative realization as fourfolds in M-theory with appropriate G-fluxes turned on. We discuss some aspects of the fourfolds including how to see the transition and a possible extension to the non-supersymmetric case.

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arXiv2001

Five-Brane Superpotentials in Heterotic M-Theory

The open supermembrane contribution to the non-perturbative superpotential of bulk space five-branes in heterotic M-theory is presented. We explicitly compute the superpotential for the modulus associated with the separation of a bulk five-brane from an end-of-the-world three-brane. The gauge and kappa-invariant boundary strings of such open supermembranes are given and the role of the holomorphic vector bundle on the orbifold fixed plane boundary is discussed in detail.

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arXiv2001

Non-Perturbative Superpotentials from Membrane Instantons in Heterotic M-Theory

A formalism for calculating the open supermembrane contribution to the non-perturbative superpotential of moduli in heterotic M-theory is presented. This is explicitly applied to the Calabi-Yau (1,1)-moduli and the separation modulus of the end-of-the-world BPS three-branes, whose non-perturbative superpotential is computed. The role of gauge bundles on the boundaries of the open supermembranes is discussed in detail, and a topological criterion presented for the associated superpotential to be non-vanishing.

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arXiv2000

Noncommutative Field Theory from String Theory: Two-loop Analysis

Noncommutative ϕ^3 field theory in six dimensions exhibits the logarithmic UV/IR mixing at the two-loop order. We show that open string theory in the presence of constant background NS-NS two-form field yields the same amplitude upon taking a decoupling limit. The stretched string picture proposed on the basis of one-loop analysis naturally generalizes to the two-loop amplitudes in consideration. Our string theory formulation can incorporate the closed string insertions as well as open string insertions. Furthermore, the analysis of the world-sheet partition function and propagators can be straightforwardly generalized to Riemann surfaces with genus zero but with an arbitrary number of boundaries.

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arXiv2000

Small Instanton Transitions in Heterotic M-Theory

We discuss non-perturbative phase transitions, within the context of heterotic M-theory, which occur when all, or part, of the wrapped five-branes in the five-dimensional bulk space come into direct contact with a boundary brane. These transitions involve the transformation of the five-brane into a ``small instanton'' on the Calabi-Yau space at the boundary brane, followed by the ``smoothing out'' of the small instanton into a holomorphic vector bundle. Small instanton phase transitions change the number of families, the gauge group or both on the boundary brane, depending upon whether a base component, fiber component or both components of the five-brane class are involved in the transition. We compute the conditions under which a small instanton phase transition can occur and present a number of explicit, phenomenologically relevant examples.

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arXiv1999

Monopole Dynamics and BPS Dyons N=2 Super-Yang-Mills Theories

We determine the low energy dynamics of monopoles in pure N=2 Yang-Mills theories for points in the vacuum moduli space where the two Higgs fields are not aligned. The dynamics is governed by a supersymmetric quantum mechanics with potential terms and four real supercharges. The corresponding superalgebra contains a central charge but nevertheless supersymmetric states preserve all four supercharges. The central charge depends on the sign of the electric charges and consequently so does the BPS spectrum. We focus on the SU(3) case where certain BPS states are realised as zero-modes of a Dirac operator on Taub-NUT space twisted by the tri-holomorphic Killing vector field. We show that the BPS spectrum includes hypermultiplets that are consistent with the strong- and weak-coupling behaviour of the Seiberg-Witten theory.

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arXiv1999

Brane mapping under $(-1)^{F_L}$

We present the evidence that $(-1)^{F_L}$ is a nonperturbative symmetry of Type II string theory. We argue that $(-1)^{F_L}$ is a symmetry of string theory as much as the $SL(2, Z)$ of the Type II string is and how the branes are mapped under the $(-1)^{F_L}$ modding. NS branes are mapped into the NS branes with the same world volume dimensions but with the different chiral structure. Supersymmetric Dp-branes (bound with anti-Dp branes) are mapped to unstable nonsupersymmetric Dp-branes, which has D(p-1)-branes as kink solutions according to Horava.

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arXiv1998

Green-Schwarz Superstring on AdS3 * S3

Green-Schwarz action of Type IIB string on $AdS_3 \times S^3$ is constructed via coset superspace approach. The construction relies exclusively on symplectically Majorana-Weyl spinor formalism, thus permitting it easier to prove $κ$-symmetry for on-shell Type IIB supergravity backgrounds.

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arXiv1998

Dual D-Brane Actions on $AdS^5 \times S^5$

Utilizing coset superspace approach, dual actions of super D1-and D3-branes on $AdS_5 \times S^5$ are constructed by carrying out duality transformation of world-volume U(1) gauge field. Resulting world-volume actions are shown to possess expected SL(2,{\bf Z}) properties. Crucial ingredient for deriving SL(2, {\bf Z}) transformation property of the D-brane actions is covariance of SU(2,2|4) coset superspace algebra under SO(2) rotation between two ten-dimensional Type IIB Majorana-Weyl spinors.

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arXiv1998

M-theory realization of a N=1 supersymmetric chiral gauge theory in four dimensions

We study M5-brane configuration of the chiral gauge theory whose Type IIA brane configuration with orientifold 6-plane(O6) is studied by various authors. Much of the paper is devoted to studying M-theory picture of SO/Sp gauge theory with fundamental flavors realized in Type IIA setup with O6-plane. The Higgs branch of N=2 SO/Sp gauge theory is studied and the curve corresponding to rotated brane configuration is presented. In the chiral gauge theory, the middle NS$^{\prime}$5-brane on top of the O6 plane is realized as a detached rational curve. Depending on a location of the rational curve in $x^7$ direction, the same curve plus the rational curve can be interpreted as describing the Coulomb branch of $SU(2N_c)$ chiral gauge theory, $SO(2N_c)/Sp(N_c)$ gauge theory with $N_f/(N_f+4)$ fundamental hypermultiplets. Various consistency checks for this proposal are made. By introducing two more rational curves corresponding to NS$^{\prime}$5-branes, one can produce a non-trivial fixed point which mediates chiral non-chiral transition.

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arXiv1997

Orientifold and F-theory Duals of CHL Strings

We present orientifold and F-theory duals of the heterotic string compactification constructed by Chaudhuri, Hockney and Lykken (CHL) which has the maximal supersymmetry but gauge group of reduced rank. The 8-dimensional dual is given by the Type IIA orientifold on the Möbius band. We show the non-trivial monodromy on the base induces non-simply laced gauge groups on the F-theory orbifolds dual to the CHL strings. The F-theory models dual to the CHL strings in six dimensions are examples of N=2 F-theory vacua. We discuss the other N=2 F-theory vacua in six dimensions.

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arXiv1997

World-Volume Action of the M Theory Five-Brane

This paper presents a 6d world-volume action that describes the dynamics of the M theory five-brane in a flat 11d space-time background. The world-volume action has global 11d super-Poincare invariance, as well as 6d general coordinate invariance and kappa symmetry, which are realized as local symmetries. The paper mostly considers a formulation in which general coordinate invariance is not manifest in one direction. However, it also describes briefly an alternative formulation, due to Pasti, Sorokin, and Tonin, in which general coordinate invariance is manifest. The latter approach requires auxiliary fields and new gauge invariances.

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arXiv1997

Dual D-Brane Actions

Dual super Dp-brane actions are constructed by carrying out a duality transformation of the world-volume U(1) gauge field. The resulting world-volume actions, which contain a (p - 2)-form gauge field, are shown to have the expected properties. Specifically, the D1-brane and D3-brane transform in ways that can be understood on the basis of the SL(2, Z) duality of type IIB superstring theory. Also, the D2-brane and the D4-brane transform in ways that are expected on the basis of the relationship between type IIA superstring theory and 11d M theory. For example, the dual D4-brane action is shown to coincide with the double-dimensional reduction of the recently constructed M5-brane action. The implications for gauge-fixed D-brane actions are discussed briefly.

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arXiv1996

A Note on Orientifolds and F-theory

An orientifold of Type-IIB theory on a $K3$ realized as a $Z_2$ orbifold is constructed which corresponds to F-theory compactification on a Calabi-Yau orbifold with Hodge numbers $(51, 3)$. The T-dual of this model is analogous to an orbifold with discrete torsion in that the action of orientation reversal has an additional phase on the twisted sectors, and both 9-branes and 5-branes carry orthogonal gauge groups. An orientifold of the $Z_3$ orbifold and its relation to F-theory is briefly discussed.

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arXiv1996

Strings on Orientifolds

We construct several examples of compactification of Type IIB theory on orientifolds and discuss their duals. In six dimensions we obtain models with $N=1$ supersymmetry, multiple tensor multiplets, and different gauge groups. In nine dimensions we obtain a model that is dual to M-theory compactified on a Klein bottle.

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