Emergent Quantum Near-Criticality from Baryonic Black Branes (2009)
Herzog, Christopher P., Klebanov, Igor R., Pufu, Silviu S., Tesileanu, Tiberiu
We find new black 3-brane solutions describing the "conifold gauge theory" at nonzero temperature and baryonic chemical potential. Of particular interest is the zero-temperature limit where we find a...
Klebanov, Igor R., Torri, Giuseppe
These notes provide a brief introduction to the ABJM theory, the level k U(N) x U(N) superconformal Chern-Simons matter theory which has been conjectured to describe N coincident M2-branes. We...
Charges of Monopole Operators in Chern-Simons Yang-Mills Theory (2009)
Benna, Marcus K., Klebanov, Igor R., Klose, Thomas
We calculate the non-abelian R-charges of BPS monopole operators in three-dimensional gauge theories with N=3 supersymmetry. This class of models includes ABJM theory, the proposed gauge theory dual...
The Squashed, Stretched, and Warped Gets Perturbed (2009)
Klebanov, Igor R., Pufu, Silviu S., Rocha, Fabio D.
We use direct Kaluza-Klein reduction to calculate the spectrum of spin-2 modes around a warped product of AdS_4 and a certain squashed and stretched 7-sphere. The modes turn out to be polynomials in...
M2-branes on Orbifolds of the Cone over Q^{1,1,1} (2009)
Franco, Sebastian, Klebanov, Igor R., Rodriguez-Gomez, Diego
We study the N=2 supersymmetric Chern-Simons quiver gauge theory recently introduced in arXiv:0809.3237 to describe M2-branes on a cone over the well-known Sasaki-Einstein manifold Q^{1,1,1}. For...
Holographic Systematics of D-brane Inflation (2008)
Baumann, Daniel, Dymarsky, Anatoly, Kachru, Shamit, Klebanov, Igor R., McAllister, Liam
We provide a systematic treatment of possible corrections to the inflaton potential for D-brane inflation in the warped deformed conifold. We consider the D3-brane potential in the presence of the...
Gauge-String Dualities and Some Applications (2008)
Benna, Marcus K., Klebanov, Igor R.
The first part of these lectures contains an introductory review of the AdS/CFT duality and of its tests. Applications to thermal gauge theory are also discussed briefly. The second part is devoted...
On Normal Modes of a Warped Throat (2007)
Benna, Marcus K., Dymarsky, Anatoly, Klebanov, Igor R., Solovyov, Alexander
As shown in arXiv:hep-th/0405282, the warped deformed conifold has two bosonic massless modes, a pseudoscalar and a scalar, that are dual to the phase and the modulus of the baryonic condensates in...
Entanglement as a Probe of Confinement (2007)
Klebanov, Igor R., Kutasov, David, Murugan, Arvind
We investigate the entanglement entropy in gravity duals of confining large $N_c$ gauge theories using the proposal of arXiv:hep-th/0603001, arXiv:hep-th/0605073. Dividing one of the directions of...
Towards an Explicit Model of D-brane Inflation (2007)
Baumann, Daniel, Dymarsky, Anatoly, Klebanov, Igor R., McAllister, Liam
We present a detailed analysis of an explicit model of warped D-brane inflation, incorporating the effects of moduli stabilization. We consider the potential for D3-brane motion in a warped conifold...
Baumann, Daniel, Dymarsky, Anatoly, Klebanov, Igor R., McAllister, Liam, Steinhardt, Paul J.
We investigate whether explicit models of warped D-brane inflation are possible in string compactifications. To this end, we study the potential for D3-brane motion in a warped conifold that includes...
Gauge/Gravity Duality and Warped Resolved Conifold (2007)
Klebanov, Igor R., Murugan, Arvind
We study supergravity backgrounds encoded through the gauge/string correspondence by the SU(N) \times SU(N) theory arising on N D3-branes on the conifold. As discussed in hep-th/9905104, the dynamics...
Baryonic Condensates on the Conifold (2006)
Benna, Marcus K., Dymarsky, Anatoly, Klebanov, Igor R.
We provide new evidence for the gauge/string duality between the baryonic branch of the cascading SU(k(M+1)) \times SU(kM) gauge theory and a family of type IIB flux backgrounds based on warped...
On D3-brane Potentials in Compactifications with Fluxes and Wrapped D-branes (2006)
Baumann, Daniel, Dymarsky, Anatoly, Klebanov, Igor R., Maldacena, Juan, McAllister, Liam, Murugan, Arvind
We study the potential governing D3-brane motion in a warped throat region of a string compactification with internal fluxes and wrapped D-branes. If the Kahler moduli of the compact space are...
On the Moduli Space of the Cascading SU(M+p)xSU(p) Gauge Theory (2005)
Dymarsky, Anatoly, Klebanov, Igor R., Seiberg, Nathan
We carry out a thorough analysis of the moduli space of the cascading gauge theory found on p D3-branes and M wrapped D5-branes at the tip of the conifold. We find various mesonic branches of the...
This talk begins with some history and basic facts about string theory and its connections with strong interactions. Comparisons of stacks of Dirichlet branes with curved backgrounds produced by them...
Variations on the Warped Deformed Conifold (2004)
Gubser, Steven S., Herzog, Christopher P., Klebanov, Igor R.
The warped deformed conifold background of type IIB theory is dual to the cascading $SU(M(p+1))\times SU(Mp)$ gauge theory. We show that this background realizes the (super-)Goldstone mechanism where...
Superconformal Gauge Theories and Non-Critical Superstrings (2004)
Klebanov, Igor R., Maldacena, Juan M.
We consider effective actions for six-dimensional non-critical superstrings. We show that the addition of $N$ units of R-R flux and of $N_f$ space-time filling D5-branes produces $AdS_5 \times S^1$...
Do Chiral Soliton Models Predict Pentaquarks? (2004)
Klebanov, Igor R., Ouyang, Peter
We reconsider the relationship between the bound state and the SU(3) rigid rotator approaches to strangeness in chiral soliton models. For non-exotic $S=-1$ baryons the bound state approach matches...
Symmetry Breaking and Axionic Strings in the Warped Deformed Conifold (2004)
Gubser, Steven S., Herzog, Christopher P., Klebanov, Igor R.
We interpret D-strings at the bottom of the warped deformed conifold as axionic strings in the dual cascading SU(N+M) x SU(N) gauge theory. The axion is a massless pseudo-scalar glueball which we...
Prospects for Pentaquark Production at Meson Factories (2004)
Browder, Thomas E., Klebanov, Igor R., Marlow, Daniel R.
Following Rosner [hep-ph/0312269], we consider B-decay production channels for the exotic I=0 and $I=3/2$ pentaquarks that have been recently reported. We also discuss new search channels for...
Is Theta+(1540) a Kaon--Skyrmion Resonance? (2003)
Itzhaki, Nissan, Klebanov, Igor R., Ouyang, Peter, Rastelli, Leonardo
We reconsider the relationship between the bound state and the SU(3) rigid rotator approaches to strangeness in the Skyrme model. For non-exotic S=-1 baryons the bound state approach matches for...
D-brane Decay in Two-Dimensional String Theory (2003)
Klebanov, Igor R., Maldacena, Juan, Seiberg, Nathan
We consider unstable D0-branes of two dimensional string theory, described by the boundary state of Zamolodchikov and Zamolodchikov [hep-th/0101152] multiplied by the Neumann boundary state for the...
Proton Decay in Intersecting D-brane Models (2003)
Klebanov, Igor R., Witten, Edward
We analyze proton decay via dimension six operators in certain GUT-like models derived from Type IIA orientifolds with $D6$-branes. The amplitude is parametrically enhanced by a factor of...
Closed String Tachyons and Their Implications for Non-Supersymmetric Strings (2003)
Dine, Michael, Gorbatov, Elie, Klebanov, Igor R., Krasnitz, Michael
Closed string tachyons have long been somewhat mysterious. We note that there is often a regime in the classical moduli space in which one can systematically compute the effective action for such...
A universal result on central charges in the presence of double-trace deformations (2002)
Gubser, Steven S., Klebanov, Igor R.
We study large N conformal field theories perturbed by relevant double-trace deformations. Using the auxiliary field trick, or Hubbard-Stratonovich transformation, we show that in the infrared the...
New Effects in Gauge Theory from pp-wave Superstrings (2002)
Klebanov, Igor R., Spradlin, Marcus, Volovich, Anastasia
It has recently been observed that IIB string theory in the pp-wave background can be used to calculate certain quantities, such as the dimensions of BMN operators, as exact functions of the...
D-Branes on the Conifold and N=1 Gauge/Gravity Dualities (2002)
Herzog, Christopher P., Klebanov, Igor R., Ouyang, Peter
We review extensions of the AdS/CFT correspondence to gauge/ gravity dualities with N=1 supersymmetry. In particular, we describe the gauge/gravity dualities that emerge from placing D3-branes at the...
PP Wave Limit and Enhanced Supersymmetry in Gauge Theories (2002)
Itzhaki, N., Klebanov, Igor R., Mukhi, Sunil
We observe that the pp wave limit of $AdS_5\times M^5$ compactifications of type IIB string theory is universal, and maximally supersymmetric, as long as $M^5$ is smooth and preserves some...
Baryon Spectra and AdS/CFT Correspondence (2002)
Berenstein, David, Herzog, Christopher P., Klebanov, Igor R.
We provide a detailed map between wrapped D3-branes in Anti-de Sitter (AdS) backgrounds and dibaryon operators in the corresponding conformal field theory (CFT). The effective five dimensional action...
A Gravity Dual of the Chiral Anomaly (2002)
Klebanov, Igor R., Ouyang, Peter, Witten, Edward
We study effects associated with the chiral anomaly for a cascading $SU(N+M)\times SU(N)$ gauge theory using gauge/gravity duality. In the gravity dual the anomaly is a classical feature of the...
On String Tensions in Supersymmetric SU(M) Gauge Theory (2001)
Herzog, Christopher P., Klebanov, Igor R.
In some models of N=1 supersymmetric SU(M) gauge dynamics (hep-th/9503163 and hep-th/9707244), the tension of a string ending on q external quarks is proportional to sin(pi q/M), q=1,..., M-1. In...
Remarks on the Warped Deformed Conifold (2001)
Herzog, Christopher P., Klebanov, Igor R., Ouyang, Peter
We assemble a few remarks on the supergravity solution of hep-th/0007191, whose UV asymptotic form was previously found in hep-th/0002159. First, by normalizing the R-R fluxes, we compare the...
String Corrections to the Holographic RG Flow of Supersymmetric SU(N) x SU(N+M) Gauge Theory (2001)
Frolov, Sergey, Klebanov, Igor R., Tseytlin, Arkady A.
We study leading string corrections to the type IIB supergravity solution dual to the ${\cal N}=1$ supersymmetric $SU(N+M)\times SU(N)$ gauge theory coupled to bifundamental chiral superfields $A_i,...
Non-Extremal Gravity Duals for Fractional D3-Branes on the Conifold (2001)
Buchel, Alexander, Klebanov, Igor R., Herzog, Christopher P., Zayas, Leopoldo A. Pando, Tseytlin, Arkady A.
The world volume theory on N regular and M fractional D3-branes at the conifold singularity is a non-conformal N = 1 supersymmetric SU (N+M) × SU(N) gauge theory. In previous work the extremal Type...
Gravity Duals of Fractional Branes in Various Dimensions (2001)
Herzog, Christopher P., Klebanov, Igor R.
We derive type II supergravity solutions corresponding to space-filling regular and fractional Dp branes on (9-p)-dimensional conical transverse spaces. Fractional Dp-branes are wrapped...
TASI Lectures: Introduction to the AdS/CFT Correspondence (2000)
This is an introductory review of the AdS/CFT correspondence and of the ideas that led to its formulation. We show how comparison of stacks of D3-branes with corresponding supergravity solutions...
The Hagedorn transition in non-commutative open string theory (2000)
Gubser, Steven S., Gukov, Sergei, Klebanov, Igor R., Rangamani, Mukund, Witten, Edward
The Hagedorn transition in non-commutative open string theory (NCOS) is relatively simple because gravity decouples. For NCOS theories in no more than five spacetime dimensions, the Hagedorn...
Stable Massive States in 1+1 Dimensional NCOS (2000)
Herzog, Christopher P., Klebanov, Igor R.
We study the case of open string theory on a D1-brane in a critical electric field. It was argued in hep-th/0006085 that the massless open string modes of this theory decouple from the massive modes,...
Klebanov, Igor R., Strassler, Matthew J.
We revisit the singular IIB supergravity solution describing M fractional 3-branes on the conifold [hep-th/0002159]. Its 5-form flux decreases, which we explain by showing that the relevant \NN=1...
1+1 Dimensional NCOS and its U(N) Gauge Theory Dual (2000)
Klebanov, Igor R., Maldacena, Juan
We study some aspects of open string theories on D-branes with critical electric fields. We show that the massless open string modes that move in the direction of the electric field decouple. In the...
Gravity Duals of Fractional Branes and Logarithmic RG Flow (1999)
Klebanov, Igor R., Nekrasov, Nikita A.
We study fractional branes in ${\CN}=2$ orbifold and ${\CN}=1$ conifold theories. Placing a large number $N$ of regular D3-branes at the singularity produces the dual ${\bf AdS}_5\times X^5$...
An Orbifold of Type 0B Strings and Non-supersymmetric Gauge Theories (1999)
Klebanov, Igor R., Nekrasov, Nikita A., Shatashvili, Samson L.
We study a ${{\IZ}}_2$ orbifold of Type 0B string theory by reflection of six of the coordinates (this theory may also be thought of as a ${{\IZ}}_4$ orbifold of Type IIB string theory by a rotation...
Absorption by Threebranes and the AdS/CFT Correspondence (1999)
In the first part of this talk I discuss two somewhat different supergravity approaches to calculating correlation functions in strongly coupled Yang-Mills theory. The older approach relates...
Tachyon Stabilization in the AdS/CFT Correspondence (1999)
We consider duality between type 0B string theory on $AdS_5\times S^5$ and the planar CFT on $N$ electric D3-branes coincident with $N$ magnetic D3-branes. It has been argued that this theory is...
AdS/CFT Correspondence and Symmetry Breaking (1999)
Klebanov, Igor R., Witten, Edward
We study, using the dual AdS description, the vacua of field theories where some of the gauge symmetry is broken by expectation values of scalar fields. In such vacua, operators built out of the...
From Threebranes to Large N Gauge Theories (1999)
This is a brief introductory review of the AdS/CFT correspondence and of the ideas that led to its formulation. Emphasis is placed on dualities between conformal large $N$ gauge theories in 4...
Asymptotic Freedom and Infrared Behavior in the Type 0 String Approach to Gauge Theory (1998)
Klebanov, Igor R., Tseytlin, Arkady A.
In a recent paper we considered the type 0 string theories, obtained from the ten-dimensional closed NSR string by a GSO projection which excludes space-time fermions, and studied the low-energy...
Baryons and Domain Walls in an N = 1 Superconformal Gauge Theory (1998)
Gubser, Steven S., Klebanov, Igor R.
Coincident D3-branes placed at a conical singularity are related to string theory on $AdS_5\times X_5$, for a suitable five-dimensional Einstein manifold $X_5$. For the example of the conifold, which...
Superconformal Field Theory on Threebranes at a Calabi-Yau Singularity (1998)
Klebanov, Igor R., Witten, Edward
Just as parallel threebranes on a smooth manifold are related to string theory on $AdS_5\times {\bf S}^5$, parallel threebranes near a conical singularity are related to string theory on $AdS_5\times...
Coupling Constant Dependence in the Thermodynamics of N=4 Supersymmetric Yang-Mills Theory (1998)
Gubser, Steven S., Klebanov, Igor R., Tseytlin, Arkady A.
The free energy of the maximally supersymmetric SU(N) gauge theory at temperature T is expected to scale, in the large N limit, as N^2 T^4 times a function of the 't Hooft coupling, f(g_{YM}^2 N). In...
Scalar Absorption and the Breaking of the World Volume Conformal Invariance (1998)
Gubser, Steven S., Hashimoto, Akikazu, Klebanov, Igor R., Krasnitz, Michael
We investigate a version of fixed scalars for non-dilatonic branes which correspond to dilatations of the brane world-volume. We obtain a cross-section whose world-volume interpretation falls out...
The Spectrum of a Large N Gauge Theory Near Transition from Confinement to Screening (1997)
Gross, David J., Hashimoto, Akikazu, Klebanov, Igor R.
We study the spectrum of 1+1 dimensional large $N$ QCD coupled to an adjoint Majorana fermion of mass $m$. As $m\to 0$ this model makes a transition from confinement to screening. We argue that in...
D-branes and Creation of Strings (1997)
We review two types of D-branes processes where open strings are created. In the first type, a closed string incident on a collection of D-branes is converted into a number of open strings running...
Schwarzschild Black Holes in Various Dimensions from Matrix Theory (1997)
Klebanov, Igor R., Susskind, Leonard
In a recent paper it was shown that the properties of Schwarzschild black holes in 8 dimensions are correctly described up to factors of order unity by Matrix theory compactified on T^3. Here we...
Absorption by Branes and Schwinger Terms in the World Volume Theory (1997)
Gubser, Steven S., Klebanov, Igor R.
We study how coincident Dirichlet 3-branes absorb incident gravitons polarized along their world volume. We show that the absorption cross-section is determined by the central term in the correlator...
Intermediate Scalars and the Effective String Model of Black Holes (1997)
Klebanov, Igor R., Rajaraman, Arvind, Tseytlin, Arkady A.
We consider five-dimensional black holes modeled by D-strings bound to D5-branes, with momentum along the D-strings. We study the greybody factors for the non-minimally coupled scalars which...
Testing Effective String Models of Black Holes with Fixed Scalars (1997)
Krasnitz, Michael, Klebanov, Igor R.
We solve the problem of mixing between the fixed scalar and metric fluctuations. First, we derive the decoupled fixed scalar equation for the four-dimensional black hole with two different charges....
World Volume Approach to Absorption by Non-dilatonic Branes (1997)
We calculate classical cross sections for absorption of massless scalars by the extremal 3-branes of type IIB theory, and by the extremal 2- and 5-branes of M-theory. The results are compared with...
Black Hole Greybody Factors and Absorption of Scalars by Effective Strings (1997)
Klebanov, Igor R., Mathur, Samir D.
We compute the greybody factors for classical black holes in a domain where two kinds of charges and their anticharges are excited by the extra energy over extremality. We compare the result to the...
Fixed scalar greybody factors in five and four dimensions (1996)
Klebanov, Igor R., Krasnitz, Michael
We perform the classical gravity calculations of the fixed scalar absorption cross-sections by D=5 black holes with three charges and by D=4 black holes with four charges. We obtain analytic results...
Absorption of Fixed scalars and the D-brane Approach to Black Holes (1996)
Callan, C G, Gubser, S S, Klebanov, Igor R, Tseytlin, Arkady A
We calculate the emission and absorption rates of fixed scalars by the near-extremal five-dimensional black holes that have recently been modeled using intersecting D-branes. We find agreement...
Trieste Spring School and Workshop (1996)
Dijkgraaf, Robbert H, Klebanov, Igor R, Narain, Kumar S, Randjbar-Daemi, S
Emission of charged particles from four- and five-dimensional black holes (1996)
Gubser, Steven S., Klebanov, Igor R.
Recently Das and Mathur found that the leading order Hawking emission rate of neutral scalars by near-extremal $D=5$ black holes is exactly reproduced by a string theoretic model involving...
On Tensionless Strings in $3+1$ Dimensions (1996)
Hanany, Amihay, Klebanov, Igor R.
We argue for the existence of phase transitions in $3+1$ dimensions associated with the appearance of tensionless strings. The massless spectrum of this theory does not contain a graviton: it...
Decay of Excited D-branes (1996)
Hashimoto, Akikazu, Klebanov, Igor R.
We calculate the leading order interactions of massless D-brane excitations. Their 4-point functions are found to be identical to those found in type I theory. The amplitude for two massless D-brane...
Spring School and Workshop on String Theory, Gauge Theory and Quantum Gravity (1996)
Dijkgraaf, R, Klebanov, Igor R, Narain, Kumar S, Randjbar-Daemi, S
D-Brane Boundary State Dynamics (1995)
Callan, Curtis G., Klebanov, Igor R.
We construct the open string boundary states corresponding to various time-dependent deformations of the D-brane and explore several ways in which they may be used to study stringy soliton collective...
A Simple Description of Strange Dibaryons in the Skyrme Model (1995)
Klebanov, Igor R., Westerberg, Karl M.
We study strange dibaryons based on the SU(2)-embedded B=2 toroidal soliton. Treating the excursions of the soliton into strange directions as small rigid oscillations, we obtain a good approximation...
Matrix Model Approach to $d>2$ Non-critical Superstrings (1995)
Hashimoto, Akikazu, Klebanov, Igor R.
We apply light-cone quantization to a $1+1$ dimensional supersymmetric field theory of large N matrices. We provide some preliminary numerical evidence that when the coupling constant is tuned to a...
Non-Perturbative Solution of Matrix Models Modified by Trace-Squared Terms (1994)
Klebanov, Igor R., Hashimoto, Akikazu
We present a non-perturbative solution of large $N$ matrix models modified by terms of the form $ g(\Tr\Phi^4)^2$, which add microscopic wormholes to the random surface geometry. For $g
Touching Random Surfaces and Liouville Gravity (1994)
Large $N$ matrix models modified by terms of the form $ g(\Tr\Phi^n)^2$ generate random surfaces which touch at isolated points. Matrix model results indicate that, as $g$ is increased to a special...
A modified c=1 matrix model with new critical behavior (1994)
Gubser, Steven S., Klebanov, Igor R.
By introducing a $\int dt \, g\left(\Tr \Phi^2(t)\right)^2$ term into the action of the $c=1$ matrix model of two-dimensional quantum gravity, we find a new critical behavior for random surfaces. The...
On Hyperfine Splittings of Strange Baryons in the Skyrme Model (1994)
Westerberg, Karl M., Klebanov, Igor R.
We calculate the complete order $1/N$ corrections to baryon masses in the rigid rotator approach to the 3-flavor Skyrme model.
Trieste Spring School and Workshop (1994)
Dijkgraaf, Robbert H, Klebanov, Igor R, Narain, Kumar S, Randjbar-Daemi, S
Exact Solution of a Boundary Conformal Field Theory (1994)
Callan, Curtis G., Klebanov, Igor R., Ludwig, Andreas W. W., Maldacena, Juan M.
We study the conformal field theory of a free massless scalar field living on the half line with interactions introduced via a periodic potential at the boundary. An SU(2) current algebra underlies...
Exact C=1 Boundary Conformal Field Theories (1993)
Callan, Curtis G., Klebanov, Igor R.
We present a solution of the problem of a free massless scalar field on the half line interacting through a periodic potential on the boundary. For a critical value of the period, this system is a...
Glueball spectrum in a (1+1)-dimensional model for QCD (1993)
Demeterfi, Krešimir, Klebanov, Igor R., Bhanot, Gyan
We consider (1+1)-dimensional QCD coupled to scalars in the adjoint representation of the gauge group SU($N$). This model results from dimensional reduction of the (2+1)-dimensional pure glue theory....
Scaling Functions for Baby Universes in Two-Dimensional Quantum Gravity (1993)
Gubser, Steven S., Klebanov, Igor R.
We apply the recently proposed transfer matrix formalism to 2-dimensional quantum gravity coupled to $(2, 2k-1)$ minimal models. We find that the propagation of a parent universe in geodesic...
Infinite symmetry and Ward identities in two-dimensional string theory (1992)
Klebanov, Igor R., Pasquinucci, Andrea
We review some of the recent progress in the continuum formulation of two-dimensional string theory, i.e. two-dimensional quantum gravity coupled to $c=1$ matter. Special attention is devoted to the...
Correlation functions from two-dimensional string Ward identities (1992)
Klebanov, Igor R., Pasquinucci, Andrea
We rederive the $w_\infty$ Ward identities, starting from the existence of trivial linearized gauge invariances, and using the method of canceled propagators in the operator formalism. Recursion...
Ward Identities in Two-Dimensional String Theory (1992)
I study the Ward identities of the $w_\infty$ symmetry of the two-dimensional string theory. It is found that, not just an isolated vertex operator, but also a number of vertex operators colliding at...
String Theory in Two Dimensions (1991)
I review some of the recent progress in two-dimensional string theory, which is formulated as a sum over surfaces embedded in one dimension.