6979808
Consistent anti-de Sitter-space/conformal-field-theory dual for a time-dependent finite temperature system.
We propose a consistent setup for the holographic dual of the strongly coupled large-Nc N=4 super Yang-Mills theory plasma which undergoes the Bjorken flow relevant to the quark-gluon plasma at BNL Relativistic Heavy Ion Collider and CERN LHC. The dual geometry is constructed order by order in a well-defined late-time expansion. The transport coefficients are determined by the regularity of the geometry. We prove, for the first time, that the dual geometry has an apparent horizon, hence, an event horizon, which covers a singularity at the origin. Further we prove that the dual geometry is regular to all orders in the late-time expansion under an appropriate choice of the transport coefficients. This choice is also shown to be unique. Our model serves as a concrete well-defined example of a time-dependent anti-de Sitter-space/conformal-field-theory dual.
17332770
Notes on the S-matrix of bosonic and topological non-critical strings
We show that the equivalence between the c = 1 non-critical bosonic string and the = 2 topologically twisted coset SL(2)/U(1) at level one can be checked very naturally on the level of tree-level scattering amplitudes with the use of the Stoyanovsky-Ribault-Teschner map, which recasts H3+ correlation functions in terms of Liouville field theory amplitudes. This observation can be applied equally well to the topologically twisted SL(2)n/U(1) coset with n > 1, which has been argued recently to be equivalent with a c < 1 non-critical bosonic string whose matter part is defined by a time-like linear dilaton CFT.
119110586
Effective temperature of nonequilibrium dense matter in holography
We study properties of effective temperature of non-equilibrium steady states by using the anti-de Sitter spacetime/conformal field theory (AdS/CFT) correspondence. We consider non-equilibrium systems with a constant flow of current along an electric field, in which the current is carried by both the doped charges and those pair created by the electric field. We find that the effective temperature agrees with that of the Langevin systems if we take the limit where the pair creation is negligible. The effect of pair creation raises the effective temperature whereas the current by the doped charges contributes to lower the effective temperature in a wide range of the holographic models.
15165421
Descent relation of tachyon condensation from boundary string field theory
We analyze how lower-dimensional bosonic D-branes further decay, using the boundary string field theory. Especially we find that the effective tachyon potential of the lower-dimensional D-brane has the same profile as that of D25-brane.
31657279
Gravity dual of spatially modulated phase
We show that the five-dimensional Maxwell theory with the Chern-Simons term is tachyonic in the presence of a constant electric field. When coupled to gravity, a sufficiently large Chern-Simons coupling causes instability of the Reissner-Nordstrom black holes in anti-de Sitter space. The instability happens only at nonvanishing momenta, suggesting a spatially modulated phase in the holographically dual quantum field theory in (3+1) dimensions, with spontaneous current generation in a helical configuration. The three-charge extremal black hole in the type IIB superstring theory on AdS_5×S^5 barely satisfies the stability condition.
117758947
OFF-SHELL BOUNDARY/CROSSCAP STATES AND ORIENTIFOLD PLANES ∗
It is well-known that extending string theory off-shell is a hard problem. In the first quantized string theory based on an action of a single string, the guiding principle is a local Weyl invariance of string worldsheets. This immediately translates into on-shellness of string scattering amplitudes. Off-shellness alone does not suggest any particular symmetry and one has to consider insertions of operators carrying dimensions of arbitrarily high degrees on the bulk of the string worldsheets: this is a hard task to carry out. Situation can be more manageable to handle if the local Weyl invariance is broken only on the boundaries of the worldsheets. To date there are two proposals for off-shell string theory through deformation on the boundary of the string worldsheets. The one is the boundary string field theory (BSFT) of Witten [1] on a unit disc and the other is the sigma model approach of open strings to the spacetime action S. (See for example Ref. [2] and the references therein.) To put simply,
118503707
Toward construction of the unified lepton-nucleus interaction model from a few hundred MeV to GeV region
Next generation neutrino oscillation experiments will need a quantitative understanding of neutrino-nucleus interaction far better than ever. Kinematics covered by the relevant neutrino-nucleus interaction spans wide region, from the quasi-elastic, through the resonance region, to the deeply inelastic scattering region. The neutrino-nucleus interaction in each region has quite different characteristics. Obviously, it is essential to combine different expertise to construct a unified model that covers all the kinematical region of the neutrino-nucleus interaction. Recently, several experimentalists and theorists got together to form a collaboration to tackle this problem. In this contribution, we report the collaboration’s recent activity and a goal in near future.
117947270
Meson spectroscopy with unitary coupled-channels model for heavy-meson decay into three mesons
We develop a model for describing excited mesons decay into three mesons. The properties of the excited mesons can be extracted with this model. The model maintains the three-body unitarity that has been missed in previous data analyses based on the conventional isobar models. We study an importance of the three-body unitarity in extracting hadron properties from data. For this purpose, we use the unitary and isobar models to analyze the same pseudo data of gamma p -> pi+pi+pi-n, and extract the properties of excited mesons. We find a significant difference between the unitary and isobar models in the extracted properties of excited mesons, such as the mass, width and coupling strength to decay channels.
118668452
Neutrino-induced forward meson-production reactions in nucleon resonance region
As a first step toward developing a reaction model that enables a comprehensive description of neutrino-nucleon reactions in the nucleon resonance region, we have applied for the first time a dynamical coupled-channels model, which successfully describes \pi N, \gamma N --> \pi N, \eta N, \pi \pi N, K\Lambda, K\Sigma reactions up to W = 2 GeV, to predict the neutrino-induced meson-production reactions with \Delta S = 0 at the forward angle limit. This has been achieved by relating the divergence of the axial-current matrix elements at Q^2 = 0 to the \pi N --> X reaction amplitudes through the PCAC hypothesis. We present the contributions from each of the \pi N, \eta N, \pi \pi N, K\Lambda, K\Sigma channels to the F_2 structure function at Q^2 --> 0 limit up to W = 2 GeV.
119109289
Explanation of the More Effective Effective Field Theory
We show that the so-called more effective effective field theory (MEEFT) is essentially equivalent to the proper nuclear effective field theory (NEFT) in describing low-energy electroweak processes in nuclei. A key to understanding their equivalence is the relation between aN EFT-based NN -potential and a phenomenological potential through the Wilsonian renormalization group equation. We also discuss an important advantage of MEEFT.
14437805
Consideration of nuclear forces from the viewpoint of the renormalization group: Relation of nuclear forces between phenomenological approach and nuclear effective field theory
A relation between nuclear forces derived using a phenomenological approach and nuclear effective field theory (NEFT) is proposed from a renormalization group point of view. A phenomenological nuclear force (V ph ) and an NEFT-based NN-potential (V EFT ) are satisfactorily related to each other through the Wilsonian renormalization group (WRG) method. It is clearly shown that use of the simple contact interactions in NEFT is adequate to simulate small scale phenomena, and that an NEFT-based NN-potential (V EFT ) is free from dependence on the model used to describe small scale phenomena. We study the characteristics of V EFT from a WRG point of view, emphasizing points that have not previously been fully recognized. We also use the V low k method and a unitary transformation method to relate V ph to V EFT . It is found that they are not appropriate for this purpose.