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The internal structure of the resonant Lambda(1405) state is investigated based on meson-baryon coupled-channels chiral dynamics, by evaluating density distributions obtained from the form factors of the Lambda(1405) state. The form factors are defined as an extension of the ordinary stable particles and are directly evaluated from the meson-baryon scattering amplitude, paying attention to the charge conservation of the probe interaction. For the resonant Lambda(1405) state we calculate the density distributions in two ways. One is on the pole position of the Lambda(1405) in the complex energy plane, which evaluates the resonant Lambda(1405) structure without contamination from nonresonant backgrounds, and another on the real energy axis around the Lambda(1405) resonance energy, which may be achieved in experiments. Using sereval probe interactions and channel decomposition, we separate the various contributions to the internal structure of the Lambda(1405). As a result, we find that the resonant Lambda(1405) state is composed of widely spread Kbar around N, which gives dominant component inside the Lambda(1405), with escaping pi Sigma component. Furthermore, we consider Kbar N bound state without decay channels, with which we can observe the internal structure of the bound state within real numbers. We also study the dependence of the form factors on the binding energy and meson mass. This verifies that the form factor defined through the scattering amplitude serves as a natural generalization of the form factor for the resonance state. The relation between the interaction strength and the meson mass shows that the physical kaon mass appears to be within the suitable range to form a molecular bound state with the nucleon through the chiral SU(3) interaction.

The internal structure of the resonant Lambda(1405) state is investigated based on meson-baryon coupled-channels chiral dynamics, by evaluating density distributions obtained from the form factors of the Lambda(1405) state. The form factors are defined as an extension of the ordinary stable particles and are directly evaluated from the meson-baryon scattering amplitude, paying attention to the charge conservation of the probe interaction. For the resonant Lambda(1405) state we calculate the density distributions in two ways. One is on the pole position of the Lambda(1405) in the complex energy plane, which evaluates the resonant Lambda(1405) structure without contamination from nonresonant backgrounds, and another on the real energy axis around the Lambda(1405) resonance energy, which may be achieved in experiments. Using sereval probe interactions and channel decomposition, we separate the various contributions to the internal structure of the Lambda(1405). As a result, we find that the resonant Lambda(1405) state is composed of widely spread Kbar around N, which gives dominant component inside the Lambda(1405), with escaping pi Sigma component. Furthermore, we consider Kbar N bound state without decay channels, with which we can observe the internal structure of the bound state within real numbers. We also study the dependence of the form factors on the binding energy and meson mass. This verifies that the form factor defined through the scattering amplitude serves as a natural generalization of the form factor for the resonance state. The relation between the interaction strength and the meson mass shows that the physical kaon mass appears to be within the suitable range to form a molecular bound state with the nucleon through the chiral SU(3) interaction.

Pion-nucleon scattering, pion photoproduction, and nucleon Compton scattering are analyzed within a scheme based on the chiral Lagrangian. Partial-wave amplitudes are obtained by an analytic extrapolation of subthreshold reaction amplitudes computed in chiral perturbation theory, where the constraints set by electromagnetic-gauge invariance, causality and unitarity are used to stabilize the extrapolation. Experimental data are reproduced up to energies $\sqrt{s}\simeq 1300$ MeV in terms of the parameters relevant at order $Q^3$. A striking puzzle caused by an old photon asymmetry measurement close to the pion production threshold is discussed.

We calculate the S-wave scattering lengths for charmed mesons scattering off Goldstone bosons and explore their quark mass dependence using chiral perturbation theory up to next-to-leading order as well as a unitarized version of it. The quark mass dependence of all scattering lengths determined in a recent lattice calculation can be reproduced by the unitarized version. We also discuss signals of possible bound states in these observables.

The 1S0 pairing gap in isospin-symmetric nuclear matter and finite nuclei is investigated using the chiral nucleon-nucleon potential at the N3LO order in the two-body sector, and the N2LO order in the three-body sector. To include realistic nuclear forces in RHB (Relativistic Hartree Bolgoliubov) calculations we rely on a separable form of the pairing interaction adjusted to the bare nuclear force. The separable pairing force is applied to the analysis of pairing properties for several isotopic and isotonic chains of spherical nuclei.

We review recent progress in implementing high-precision chiral two- and three-body forces in nuclear many-body systems beyond light nuclei. We begin with applications to finite nuclei, which we study through the nuclear shell model and self-consistent mean field theory. We then turn our attention to infinite nuclear matter treated within the framework of Landau's theory of normal Fermi liquids.

In this talk I summarize recent findings around the description of axial vector mesons as dynamically generated states from the interaction of pseudoscalar mesons and vector mesons, dedicating some attention to the two $K_1(1270)$ states. Then I review the generation of open and hidden charm scalar and axial states, and how some recent experiment supports the existence of the new hidden charm scalar state predicted. I present recent results showing that the low lying $1/2^+$ baryon resonances for S=-1 can be obtained as bound states or resonances of two mesons and one baryon in coupled channels. Then show the differences with the S=0 case, where the $N^*(1710)$ appears also dynamically generated from the two pion one nucleon system, but the $N^*(1440)$ does not appear, indicating a more complex structure of the Roper resonance. Finally I shall show how the state X(2175), recently discovered at BABAR and BES, appears naturally as a resonance of the $\phi K \bar{K}$ system.

The electromagnetic mean squared radii, _E and _M, of Lambda(1405) are calculated in the chiral unitary model. We describe the excited baryons as dynamically generated resonances in the octet meson and octet baryon scattering. We evaluate values of _E and _M for the Lambda(1405) on the resonance pole and obtain their complex values. We also consider Lambda(1405) obtained by neglecting decay channels. For the latter case, we obtain negative and larger absolute electric mean squared radius than that of typical ground state baryons. This implies that Lambda(1405) has structure that K^- is widely spread around p.

A recently introduced relativistic nuclear energy density functional, constrained by features of low-energy QCD, is extended to describe the structure of hypernuclei. The density-dependent mean field and the spin-orbit potential of a $\Lambda$-hyperon in a nucleus, are consistently calculated using the SU(3) extension of in-medium chiral perturbation theory. The leading long-range $\Lambda N$ interaction arises from kaon-exchange and $2\pi$-exchange with a $\Sigma$-hyperon in the intermediate state. Scalar and vector mean fields, originating from in-medium changes of the quark condensates, produce a sizeable {\em short-range} spin-orbit interaction. The model, when applied to oxygen as a test case, provides a natural explanation for the smallness of the effective $\Lambda$ spin-orbit potential: an almost complete cancellation between the background contributions (scalar and vector) and the long-range terms generated by two-pion exchange.

Using the linear sigma model, we study the evolutions of the quark condensate and of the nucleon mass in the nuclear medium. Our formulation of the model allows the inclusion of both pion and scalar-isoscalar degrees of freedom. It guarantees that the low energy theorems and the constrains of chiral perturbation theory are respected. We show how this formalism incorporates quantum hadro-dynamics improved by the pion loops effects.

The environment generated in the mid-rapidity region of a high-energy nuclear collision endows the pionic degrees of freedom with a time-dependent effective mass. Its specific evolution provides a mechanism for the production of back-to-back charge-conjugate pairs of soft pions which may present an observable signal of the non-equilibrium dynamics of the chiral order parameter.

In these lectures I make an introduction to chiral unitary theory applied to the meson baryon interaction and show how several well known resonances are dynamically generated, and others are predicted. Two very recent experiments are analyzed, one of them showing the existence of two $\Lambda(1405)$ states and the other one providing support for the $\Lambda(1520)$ resonance as a quasibound state of $\Sigma(1385) \pi$. The use of chiral Lagrangians to account for the hadronic interaction at the elementary level introduces a new approach to deal with the modification of meson and baryon properties in a nuclear medium. Examples of it for $\bar{K}$, $\eta$ and $\phi$ modification in the nuclear medium are presented.

In these lectures I make an introduction to chiral unitary theory applied to the meson baryon interaction and show how several well known resonances are dynamically generated, and others are predicted. Two very recent experiments are analyzed, one of them showing the existence of two $\Lambda(1405)$ states and the other one providing support for the $\Lambda(1520)$ resonance as a quasibound state of $\Sigma(1385) \pi$. The use of chiral Lagrangians to account for the hadronic interaction at the elementary level introduces a new approach to deal with the modification of meson and baryon properties in a nuclear medium. Examples of it for $\bar{K}$, $\eta$ and $\phi$ modification in the nuclear medium are presented.

A systematic calculation of nuclear matter is performed which includes the long-range correlations between nucleons arising from one- and two-pion exchange. Three-body effects from $2\pi$-exchange with excitations of virtual $\Delta(1232)$-isobars are also taken into account in our diagrammatic calculation of the energy per particle $\bar E(k_f)$. In order to eliminate possible high-momentum components from the interactions we introduce at each pion-baryon vertex a form factor of monopole type. The empirical nuclear matter saturation point, $\rho_0 \simeq 0.16 $fm$^{-3}$, $\bar E_0\simeq -16 $MeV, is well reproduced with a monopole mass of $\Lambda \simeq 4\pi f_\pi \simeq 1.16 $GeV. As in the recent approach based on the universal low-momentum $NN$-potential $V_{\rm low-k}$, the inclusion of three-body effects is crucial in order to achieve saturation of nuclear matter. We demonstrate that the dependence of the pion-exchange contributions to $\bar E(k_f)$ on the ''resolution'' scale $\Lambda$ can be compensated over a wide range of $\Lambda$ by counterterms with two ''running'' contact-couplings. As a further application we study the in-medium chiral condensate $ (\rho)$ beyond the linear density approximation. For $\rho \leq 1.5 \rho_0$ we find small corrections from the derivative $d \bar E(k_f)/d m_\pi$, which are stable against variations of the monopole regulator mass $\Lambda$.

Based on the Weinberg lagrangian or, in a new language, the lagrangian of hidden local symmetry added with the term induced by the anomalous lagrangian of Wess and Zumino, the dynamics of the decays rho to 4 pi and omega to 5 pi is considered. The excitation curves of rho resonance in its decay to 4 pi are obtained for the first time. The comparison with recent CMD-2 data is given. The partial widths of the decays omega to 2 pi^+ 2 pi^- pi^0 and omega to pi^+ pi^- 3 pi^0 which can be measured on colliders with luminosity 10^{33}{cm }^{-2}{s}^{-1} are evaluated for the first time.

Chiral bosons are important building blocks in the study of supergravity, string theory and quantum Hall effect. Along the last two decades many different formulations have appeared trying to describe the dynamics and the quantization of these curious objects. However two of them have gain special attention among people working on this area: the gauge invariant formulation proposed by Siegel and the noninvariant one put forward by Floreanini and Jackiw. We call these distinct analysis as chiral bosonization schemes (CBS). In this report we make a study of the relationships among many of these different chiral bosonization schemes. This is done in the context canonical framework with two different techniques known as soldering formalism and dual projection formalism. The first considers the phenomenon of interference between chiral modes and the second is able to separate dynamics from the symmetry behavior in a quantum field theory. While the soldering formalism discloses phenomena analogous to the double slit interference phenomena in classical-quantum physics with important consequences to the bosonization program, the dual projection, in particular, is able to disclose the presence of a noton, a nonmover field, in different formulations for chiral bosons. The importance of this last result is that it proves the duality between Siegel and Floreanini-Jackiw model without invoking gauge-fixing: while the Floreanini-Jackiw component describes the dynamics, it is the noton that carries the symmetry contents, acquiring dynamics upon quantization and is fully responsible for the Siegel anomaly.

It is shown from rigorous three-body Faddeev calculations that the masses of all 14 lowest states in the $N$ and $\Delta$ spectra can be described within a constituent quark model with a Goldstone-boson-exchange interaction plus linear confinement between the constituent quarks.

We discuss the formation of s- and d-wave baryon resonances as predicted by the chiral SU(3) symmetry of QCD. Based on the leading order term of the chiral Lagrangian a rich spectrum of molecules is generated, owing to final-state interactions. The spectrum of s- and d-wave baryon states with zero and non-zero charm is remarkably consistent with the empirical pattern. In particular, the recently announced Sigma_c(2800) of the BELLE collaboration is reproduced with realistic mass and width parameters. Similarly, the d-wave states Lambda_c(2625) and Xi_c(2815) are explained naturally to be chiral excitations of J^P=3/2^+ states. In the open-charm sector exotic multiplet structures are predicted. These findings support a radical conjecture: meson and baryon resonances that do not belong to the large-N_c ground state of QCD should be viewed as hadronic molecular states

We derive the linear Langevin equation that describes the behavior of the fluctuations of the order parameter of the chiral phase transition above the critical temperature by applying the projection operator method to the Nambu-Jona-Lasinio model at finite temperature and density. The Langevin equation relaxes exhibiting oscillation, reveals thermalization and converges to the equilibrium state consistent with the mean-field approximation as time goes on. With the help of this Langevin equation, we further investigate the relaxation of the critical fluctuations. The relaxation time of the critical fluctuations increases at speed as the temperature approaches toward the critical temperature because of the critical slowing down. The critical slowing down is enhanced as the chemical potential increases because of the Pauli blocking. Furthermore, we find another enhancement of the critical slowing down around the tricritical point.

We report on a recent theoretical work on the structure of the Lambda(1405) resonance within a chiral unitary approach, in which the resonance is dynamically generated in meson-baryon scattering. Studying the analytic structure of the scattering amplitude, we have found that there are two poles lying around energies of Lambda(1405) with different widths and couplings to the meson-baryon states. We discuss reactions to conform the double pole structure in experiment and elastic K^- p scattering at low energies.

We use the linear $\sigma$ model to analyse the dynamics of a disoriented chiral condensate. For idealized boundary conditions appropriate to high energy collisions, the problem can be reduced to a one dimensional one. The evolution of the chiral state is then that of a simple dynamical system and can be studied analytically.

Some recent developments in the description of nuclear forces and few-nucleon dynamics derived from chiral effective field theory are reviewed.

The critical dynamics of the chiral symmetry breaking induced by gauge interaction is examined in the Wilson renormalization group framework in comparison with the Schwinger-Dyson approach. We derive the beta functions for the four-fermi couplings in the sharp cutoff renormalzation group scheme, from which the critical couplings and the anomalous dimensions of the fermion composite operators near criticality are immediately obtained. It is also shown that the beta functions lead to the same critical behavior found by solving the so-called ladder Schwinger-Dyson equation, if we restrict the radiative corrections to a certain limited type.

We investigate the low-temperature phase of QCD and the crossover region with two light flavors of quarks. The chiral expansion around the point $(T, m_q = 0)$ in the temperature vs. quark-mass plane indicates that a sharp real-time excitation exists with the quantum numbers of the pion. We determine its dispersion relation and test the applicability of the chiral expansion. The time-dependent correlators are also analyzed using the Maximum Entropy Method (MEM), yielding consistent results. Finally, we test the predictions of ordinary chiral perturbation theory around the point $(T = 0, m_q = 0)$ for the temperature dependence of static observables. Around the crossover temperature, we find that all quantities considered depend only mildly on the quark mass in the considered range 8MeV $\leq \bar{m}^{\bar{\text{MS}}} \leq$ 15MeV.

Recently spin textures called skyrmions have been discovered in certain chiral magnetic materials without spatial inversion symmetry, and have attracted enormous attention due to their promising application in spintronics since only a low applied current is necessary to drive their motion. When a conduction electron moves around the skyrmion, its spin is fully polarized by the spin texture and acquires a quantized phase; thus, the skyrmion yields an emergent electrodynamics that in turn determines skyrmion motion and gives rise to a finite Hall angle. While Skyrmions behave as particles, no particle level description of their dynamics exists to date. Such a model would have tremendous impact on understanding skyrmion dynamics by theoretical analysis and computational modeling. Here we derive the equation of motion from a microscopic continuum model and obtain the short-range interaction between skyrmions, and the interaction between skyrmions and defects. Skyrmions also experience a Magnus force perpendicular to their velocity due to the underlying emergent electromagnetic field. We validate the equation of motion by studying the depinning transition using both the particle and the continuum models. By using the particle description, we explain the recent experimental observations of the rotation of a skyrmion lattice in the presence of a temperature gradient. We also predict quantum and thermal creep motion of skyrmions in the pinning potential.

We investigate the QCD phase diagram by using the strong-coupling expansion of the lattice QCD with one species of staggered fermion and the Polyakov loop effective action at finite temperature (T) and quark chemical potential (mu). We derive an analytic expression of effective potential Feff including both the chiral (U(1)) and the deconfinement (Z_Nc) dynamics with finite coupling effects in the mean-field approximation. The Polyakov loop increasing rate (dl/dT) is found to have two peaks as a function of T for small quark masses. One of them is the chiral-induced peak associated with the rapid decrease of the chiral condensate. The temperature of the other peak is almost independent of the quark mass or chemical potential, and this peak is interpreted as the Z_Nc-induced peak.

We study the dynamics of skyrmions under spin-transfer torque in Dzyaloshinskii-Moriya materials with easy-axis anisotropy. In particular, we study the motion of a topological skyrmion with skyrmion number $Q=1$ and a non-topological skyrmionium with $Q=0$ using their linear momentum, virial relations, and numerical simulations. The non-topological $Q=0$ skyrmionium is accelerated in the direction of the current flow and it either reaches a steady state with constant velocity, or it is elongated to infinity. The steady-state velocity is given by a balance between current and dissipation and has an upper limit. In contrast, the topological $Q=1$ skyrmion converges to a steady-state with constant velocity at an angle to the current flow. When the spin current stops the $Q=1$ skyrmion is spontaneously pinned whereas the $Q=0$ skyrmionium continues propagation. Exact solutions for the propagating skyrmionium are identified as solutions of equations given numerically in a previous work. Further exact results for propagating skyrmions are given in the case of the pure exchange model. The traveling solutions provide arguments that a spin-polarized current will cause rigid motion of a skyrmion or a skyrmionium.

We investigate the neutral pion photoproduction on the proton near threshold in covariant chiral perturbation theory with the explicit inclusion of Delta degrees of freedom. This channel is specially sensitive to chiral dynamics and the advent of very precise data from the Mainz microtron has shown the limits of the convergence of the chiral series for both the heavy baryon and the covariant approaches. We show that the inclusion of the Delta resonance substantially improves the convergence leading to a good agreement with data for a wider range of energies.

Topologically protected swirl of the magnetic texture known as the Skyrmion has become ubiqui- tous in both metallic and insulating chiral magnets. Meanwhile the existence of its three-dimensional analogue, known as the magnetic monopole, has been suggested by various indirect experimental sig- natures in MnGe compound. Theoretically, Ginzburg-Landau arguments in favor of the formation of a three-dimensional crystal of monopoles and anti-monopoles have been put forward, however no microscopic model Hamiltonian was shown to support such a phase. Here we present strong numerical evidence from Monte Carlo simulations for the formation of a rock-salt crystal structure of monopoles and anti-monopoles in short-period chiral magnets. Real-time simulation of the spin dynamics suggests there is only one collective mode in the monopole crystal state in the frequency range of several GHz for the material parameters of MnGe.

Recent studies show superconductivity provides new perspectives on spintronics. We study a heterostructure composed of an s-wave superconductor and a cubic chiral-magnet that can stabilize a topological spin texture, a skyrmion. We propose a supercurrent-induced spin torque that originates from the spin-orbit coupling, and we show that the spin torque can drive a skyrmion in an efficient way that reduces Joule heating. We also study the band structure of Bogoliubov quasiparticles and show the existence of Weyl points, whose positions can be controlled by the direction of the magnetization. This results in an effective magnetic field acting on the quasiparticles in the presence spin textures. Furthermore, the tilt of the Weyl cones can also be tuned by the strength of the spin-orbit coupling, and we propose a possible realization of type-II Weyl points.

The nature of the Lambda(1405) is discussed based on the unitarised coupled-channels approach with chiral dynamics (chiral unitary model). This approach describes the Kbar N scattering cross sections and the Lambda(1405) spectra phenomenologically very well. With this successful description of Lambda(1405), it is found that the Lambda(1405) is composed by two resonance states having different coupling nature to the meson-baryon states. As a consequence, the resonance position in the pi Sigma invariant mass spectrum depends on the initial channel of the Lambda(1405) production. To observe the Lambda(1405) initiated by the Kbar N channel, K^- d to Lambda(1405) n is one of the most favorable reactions. Hadronic molecule states with kaons are also discussed by emphasizing an important role of Lambda(1405) as a quasibound state of Kbar N.

Using recently proposed method of discrete Hirota dynamics for integrable (1+1)D quantum field theories on a finite space circle of length L, we derive and test numerically a finite system of nonlinear integral equations for the exact spectrum of energies of SU(N)xSU(N) principal chiral field model as functions of m L, where m is the mass scale. We propose a determinant solution of the underlying Y-system, or Hirota equation, in terms of determinants (Wronskians) of NxN matrices parameterized by N-1 functions of the spectral parameter, with the known analytical properties at finite L. Although the method works in principle for any state, the explicit equations are written for states in the U(1) sector only. For N>2, we encounter and clarify a few subtleties in these equations related to the presence of bound states, absent in the previously considered N=2 case. In particular, we solve these equations numerically for a few low-lying states for N=3 in a wide range of m L.

Nuclear theory has entered an exciting era. This is due to advances on many fronts, including the development of effective field theory and the renormalization group for nuclear forces, advances in ab-initio methods for nuclear structure, an effort to develop a universal density functional based on microscopic interactions, and the application of large-scale computing resources. I discuss their impact, recent highlights and the frontiers in understanding and predicting nuclei and the structure of strongly-interacting matter based on chiral interactions.

In an accompanying paper [arXiv:0903.0011v1] we have studied the equilibrium properties of vortices in a chiral quasi-twodimensional triplet superfluid/superconductor. Here we extend our studies to include the dynamical response of a vortex core in a chiral triplet superconductor to an external a.c. electromagnetic field. We consider in particular the response of a doubly quantized vortex with a homogeneous core in the time-reversed phase. The external frequencies are assumed to be comparable in magnitude to the superconducting gap frequency, such that the vortex motion is non-stationary but can be treated by linear response theory. We include broadening of the vortex core bound states due to impurity scattering and consider the intermediate clean regime, with a broadening comparable to or larger than the quantized energy level spacing. The response of the order parameter, impurity self energy, induced fields and currents are obtained by a self-consistent calculation of the distribution functions and the excitation spectrum. Using these results we obtain the self-consistent dynamically induced charge distribution in the vicinity of the core. This charge density is related to the nonequilibrium response of the bound states and order parameter collective mode, and dominates the electromagnetic response of the vortex core.

In an accompanying paper [arXiv:0903.0011v1] we have studied the equilibrium properties of vortices in a chiral quasi-twodimensional triplet superfluid/superconductor. Here we extend our studies to include the dynamical response of a vortex core in a chiral triplet superconductor to an external a.c. electromagnetic field. We consider in particular the response of a doubly quantized vortex with a homogeneous core in the time-reversed phase. The external frequencies are assumed to be comparable in magnitude to the superconducting gap frequency, such that the vortex motion is non-stationary but can be treated by linear response theory. We include broadening of the vortex core bound states due to impurity scattering and consider the intermediate clean regime, with a broadening comparable to or larger than the quantized energy level spacing. The response of the order parameter, impurity self energy, induced fields and currents are obtained by a self-consistent calculation of the distribution functions and the excitation spectrum. Using these results we obtain the self-consistent dynamically induced charge distribution in the vicinity of the core. This charge density is related to the nonequilibrium response of the bound states and order parameter collective mode, and dominates the electromagnetic response of the vortex core.

In an accompanying paper [arXiv:0903.0011v1] we have studied the equilibrium properties of vortices in a chiral quasi-twodimensional triplet superfluid/superconductor. Here we extend our studies to include the dynamical response of a vortex core in a chiral triplet superconductor to an external a.c. electromagnetic field. We consider in particular the response of a doubly quantized vortex with a homogeneous core in the time-reversed phase. The external frequencies are assumed to be comparable in magnitude to the superconducting gap frequency, such that the vortex motion is non-stationary but can be treated by linear response theory. We include broadening of the vortex core bound states due to impurity scattering and consider the intermediate clean regime, with a broadening comparable to or larger than the quantized energy level spacing. The response of the order parameter, impurity self energy, induced fields and currents are obtained by a self-consistent calculation of the distribution functions and the excitation spectrum. Using these results we obtain the self-consistent dynamically induced charge distribution in the vicinity of the core. This charge density is related to the nonequilibrium response of the bound states and order parameter collective mode, and dominates the electromagnetic response of the vortex core.

In this contribution we report a recently developed Anomalous-Viscous Fluid Dynamics (AVFD) framework, which simulates the evolution of fermion currents in QGP on top of the bulk expansion from data-validated VISHNU hydrodynamics. With reasonable estimates of initial conditions and magnetic field lifetime, the predicted CME signal is quantitatively consistent with change separation measurements in 200GeV Au-Au collisions at RHIC. We further develop the event-by-event AVFD simulations that allow direct evaluation of two-particle correlations arising from CME signal as well as the non-CME backgrounds. Finally we report predictions from AVFD simulations for the upcoming isobaric (Ru-Ru v.s. Zr-Zr ) collisions that could provide the critical test of the CME in heavy ion collisions.

In a hard-wall model of holographic QCD, we find that nonlinear boundary dynamics are required in order to maintain the correct pattern of explicit and spontaneous chiral symmetry breaking beyond leading order in the pion fields. With the help of a field redefinition, we relate the requisite nonlinear boundary conditions to a standard Sturm-Liouville system. Observables insensitive to the chiral limit receive only small corrections in the improved description, and classical calculations in the hard-wall model remain surprisingly accurate.

Topological excitations in the QCD vacuum take the form of coherent codimension one sheets with positive and negative sheets juxtaposed in a dipole layer. These sheets may be interpreted as Luscher's "Wilson bags," which are domain walls between discrete quasivacua labelled by a local value of the $\theta$ parameter equal to $2\pi k$, with $k$ given by the number of units of background Ramond-Ramond flux. This picture of the vacuum is closely analogous to Coleman's description of the 2D massive Schwinger model, where $\theta$ is interpreted as a background electric field, and a pointlike charged particle is a domain wall between vacua which differ by one unit of background electric flux. The main effect of the Ramond-Ramond U(1) field in low energy QCD dynamics is the generation of phenomenologically important contact terms: (1) The dominant contact term in the topological charge correlator which leads to positive topological susceptibility, (2) The $\eta'$ mass insertion, and (3) An $SU(N_f)\times SU(N_f)$ invariant Nambu-Jona Lasinio 4-quark interaction.

The processes involving $K^{-}p, KN, \Sigma\pi, \Lambda\pi,\Sigma\eta, \Lambda\eta$ coupled channels are studied in the nonperturbative chiral approach. An effective potential is constructed using a chiral meson-baryon Lagrangian at lowest order. This potential is iterated to all orders with the Lippmann-Schwinger equation. A reasonable fit of the experimental data is obtained. It is pointed out, however, that due to a strong sensitivity of the results to the value of the cut-off, such an approach should be viewed as a rather phenomenological way to fit the experimental data since there is no small expansion parameter allowing for truncation of the chiral expansion of the effective potential at some given order. A possible way to construct the consistent chiral expansion is briefly discussed

We study brane realizations of chiral matter in N=1 supersymmetric gauge theories in four dimensions. A "cross" configuration which leads to "flavor doubling" is found to have a superpotential. The main example is realized using a special "fork" configuration. Many of the results are found by studying a SU times SU product gauge group first. The chiral theory is then an orientifold projection of the product gauge group. An interesting observation in the brane picture is that there are transitions between chiral and non chiral models. These transitions are closely related to small instanton transitions in six dimensions.

We extend our recent non-perturbative chiral SU(3) coupled channel approach to pion- and photon-induced $\eta$- and $K$-meson production off protons by including all strong and electromagnetic p-wave multipoles. We identify the p-wave amplitudes of the next-to-leading order SU(3) chiral meson-baryon Lagrangian with a coupled channel potential which is iterated to infinite orders in a separable Lippmann-Schwinger equation. Our approach to $\eta$- and $K$-photoproduction introduces no additional free parameters. By adjusting a few finite range parameters and the unknown parameters in the Lagrangian, we are able to simultaneously describe a very large amount of low-energy data. These include the total and differential cross sections of the $\pi$-induced reactions $\pi^- p \to \eta n, K^0 \Lambda, K^0 \Sigma^0, K^+ \Sigma^-$ and $\pi^+ p \to K^+ \Sigma^+$ as well as those of photoproduction $\gamma p \to \eta p, K^+\Lambda, K^+ \Sigma^0, K^0 \Sigma^+$. The polarization observables measured in $\eta$- and $K$-photoproduction are particularly sensitive to interference terms between the s- and p-wave multipoles. The total cross section data are remarkably well reproduced in all channels. There remain, however, some open questions concerning details of angular distributions and polarization observables.

We investigate the structure of the Lambda(1405) resonance and Kbar N phenomenology in the perspective of chiral SU(3) dynamics. Utilizing the chiral coupled-channel approach which well describes the Kbar N scattering observable, we perform three different analyses to clarify the structure of the Lambda(1405) resonance. The results consistently indicate the meson-baryon molecule picture of the Lambda(1405). We argue the consequence of the chiral dynamics in Kbar N phenomenology and the antikaon bound state in nucleus, emphasizing the important role of the strong pi Sigma interaction.

The chiral limit of the rho and sigma masses and widths is discussed. We work within the inverse amplitude method to one loop in SU(2) ChPT and analyze the consequences that all chiral logarithms cancel out in the rho-channel, while they do not cancel for the sigma case, and how they strongly influence the properties of this latter resonance. Our results confirm and explain the different behavior of the sigma and rho poles for NC not far from 3, but we extend the analysis to very large NC, where the behavior of these two resonances is re-analyzed. We note that the rather natural requirement of consistency between resonance saturation and unitarization imposes useful constraints. By looking only at the rho-channel, and within the single resonance approximation, we find that the masses of the first vector and scalar meson nonets, invoked in the single resonance approximation, turn out to be degenerated in the large NC limit. On the contrary we show that, for sufficiently large NC, the scalar meson evolution lies beyond the applicability reach of the one-loop inverse amplitude method and if the scalar channel is also incorporated in the analysis, it may lead, in some cases, to phenomenologically inconsistent results.

The chiral limit of the rho and sigma masses and widths is discussed. We work within the inverse amplitude method to one loop in SU(2) ChPT and analyze the consequences that all chiral logarithms cancel out in the rho-channel, while they do not cancel for the sigma case, and how they strongly influence the properties of this latter resonance. Our results confirm and explain the different behavior of the sigma and rho poles for NC not far from 3, but we extend the analysis to very large NC, where the behavior of these two resonances is re-analyzed. We note that the rather natural requirement of consistency between resonance saturation and unitarization imposes useful constraints. By looking only at the rho-channel, and within the single resonance approximation, we find that the masses of the first vector and scalar meson nonets, invoked in the single resonance approximation, turn out to be degenerated in the large NC limit. On the contrary we show that, for sufficiently large NC, the scalar meson evolution lies beyond the applicability reach of the one-loop inverse amplitude method and if the scalar channel is also incorporated in the analysis, it may lead, in some cases, to phenomenologically inconsistent results.

The chiral limit of the rho and sigma masses and widths is discussed. We work within the inverse amplitude method to one loop in SU(2) ChPT and analyze the consequences that all chiral logarithms cancel out in the rho-channel, while they do not cancel for the sigma case, and how they strongly influence the properties of this latter resonance. Our results confirm and explain the different behavior of the sigma and rho poles for NC not far from 3, but we extend the analysis to very large NC, where the behavior of these two resonances is re-analyzed. We note that the rather natural requirement of consistency between resonance saturation and unitarization imposes useful constraints. By looking only at the rho-channel, and within the single resonance approximation, we find that the masses of the first vector and scalar meson nonets, invoked in the single resonance approximation, turn out to be degenerated in the large NC limit. On the contrary we show that, for sufficiently large NC, the scalar meson evolution lies beyond the applicability reach of the one-loop inverse amplitude method and if the scalar channel is also incorporated in the analysis, it may lead, in some cases, to phenomenologically inconsistent results.

We develop the single-channel local potential for the KbarN system, which is applicable to quantitative studies of Kbar bound states in nuclei. Because the high precision measurement of the kaonic hydrogen by SIDDHARTA reduces the uncertainty of the KbarN amplitude below the KbarN threshold, the local potential should be calibrated in a wide energy region. We establish a new method to construct the local potential focusing on the behavior of the scattering amplitude in the complex energy plane. Applying this method, we construct the KbarN potential based on the chiral coupled-channel approach with the SIDDHARTA constraint. The wave function from the new potential indicates the KbarN molecular structure of Lambda(1405).

I discuss several topics in chiral perturbation theory - in particular, I recall pecularities of the chiral expansion in the baryon sector.

We develop a manifestly Lorentz covariant chiral quark model for the study of baryons as bound states of constituent quarks dressed by a cloud of pseudoscalar mesons. The approach is based on a non-linear chirally symmetric Lagrangian, which involves effective degrees of freedom - constituent quarks and the chiral (pseudoscalar meson) fields. In a first step, this Lagrangian can be used to perform a dressing of the constituent quarks by a cloud of light pseudoscalar mesons and other heavy states using the calculational technique of infrared dimensional regularization of loop diagrams. We calculate the dressed transition operators with a proper chiral expansion which are relevant for the interaction of quarks with external fields in the presence of a virtual meson cloud. In a second step, these dressed operators are used to calculate baryon matrix elements. Applications are worked out for the masses of the baryon octet, the meson-nucleon sigma terms, the magnetic moments of the baryon octet, the nucleon charge radii, the strong vector meson-nucleon couplings and the full momentum dependence of the electromagnetic form factors of the nucleon.

We study s-wave scattering of a hadron and a Nambu-Goldstone boson induced by the model-independent low energy interaction in the flavor SU(3) symmetric limit. Establishing the general structure of the low energy interaction based on group theoretical arguments, we find that the interaction in the exotic channels are in most cases repulsive, and that for possible attractive channels the interaction strengths are weak and uniquely given independent of channel. Solving the scattering problem with this interaction, we show that the attraction in the exotic channels is not strong enough to generate a bound state from the physically known target hadrons. We also find that there are no attractive interaction in the exotic channels in large Nc limit.