Constraints on hard spectator scattering and annihilation corrections in Bu,d→PV decays within QCD factorization

In this paper, we investigate the contributions of hard spectator scattering and annihilation in B→PV decays within the QCD factorization framework. With available experimental data on B→πK⁎,ρK,πρ and Kϕ decays, comprehensive χ2 analyses of the parameters XA,Hi,f(ρA,Hi,f,ϕA,Hi,f) are performed, where XAf(XAi) and XH are used to parameterize the endpoint divergences of the (non)factorizable annihilation and hard spectator scattering amplitudes, respectively. Based on χ2 analyses, it is observed that (1) The topology-dependent parameterization scheme is feasible for B→PV decays; (2) At the current accuracy of experimental measurements and theoretical evaluations, XH=XAi is allowed by B→PV decays, but XH≠XAf at 68% C.L.; (3) With the simplification XH=XAi , parameters XAf and XAi should be treated individually. The above-described findings are very similar to those obtained from B→PP decays. Numerically, for B→PV decays, we obtain (ρA,Hi,ϕA,Hi[°])=(2.87−1.95+0.66,−145−21+14) and (ρAf,ϕAf[°])=(0.91−0.13+0.12,−37−9+10) at 68% C.L. With the best-fit values, most of the theoretical results are in good agreement with the experimental data within errors. However, significant corrections to the color-suppressed tree amplitude α2 related to a large ρH result in the wrong sign for ACPdir(B−→π0K⁎−) compared with the most recent BABAR data, which presents a new obstacle in solving “ ππ ” and “ πK ” puzzles through α2 . A crosscheck with measurements at Belle (or Belle II) and LHCb, which offer higher precision, is urgently expected to confirm or refute such possible mismatch

Two-loop master integrals with the simplified differential equations approach

We calculate the complete set of two-loop Master Integrals with two off massshell legs with massless internal propagators, that contribute to amplitudes of diboson V 1 V 2 production at the LHC. This is done with the Simplified Differential Equations approach to Master Integrals, which was recently proposed by one of the authors

Rare decay π0→e+e- : on corrections beyond the leading order

The preceding experimental and theoretical results on the rare decay π0→e+e- are briefly summarized. Already computed two-loop QED corrections are reviewed and the bremsstrahlung contribution beyond the soft-photon approximation is analytically calculated. The possible further contribution of QCD loop corrections is estimated using the leading logarithm approximation. The complete result can be used to fit the value of the contact interaction coupling χ(r) to the recent KTeV experiment with the result χ(r)(Mρ)=4.5±1.0

Unification of Galileon dualities

We study dualities of the general Galileon theory in d dimensions in terms of coordinate transformations on the coset space corresponding to the spontaneously broken Galileon group. The most general duality transformation is found to be determined uniquely up to four free parameters and under compositions these transformations form a group which can be identified with GL (2 , R ). This group represents a unified framework for all the up to now known Galileon dualities. We discuss a representation of this group on the Galileon theory space and using concrete examples we illustrate its applicability both on the classical and quantum level

Isobaric yield ratio difference and Shannon information entropy

The Shannon information entropy theory is used to explain the recently proposed isobaric yield ratio difference (IBD) probe which aims to determine the nuclear symmetry energy. Theoretically, the difference between the Shannon uncertainties carried by isobars in two different reactions ( ΔIn21 ), is found to be equivalent to the difference between the chemical potentials of protons and neutrons of the reactions [the IBD probe, IB- Δ(βμ)21 , with β the reverse temperature]. From the viewpoints of Shannon information entropy, the physical meaning of the above chemical potential difference is interpreted by ΔIn21 as denoting the nuclear symmetry energy or density difference between neutrons and protons in reactions more concisely than from the statistical ablation–abrasion model

Tension of confining strings at low temperature

In the low temperature confining phase of QCD or QCD-like theories it is challenging to capture the temperature dependence of observables through AdS/CFT. Using the blackfold approach we compute the quark-anti-quark linear static potential in the low temperature confining phase, taking into account the thermal excitations of the string. We find the explicit temperature dependence of the string tension and notice that, as naturally expected, tension decreases as temperature increases. We have also generalized the blackfold approach for the computation of the Wilson loops, making it directly applicable to a large class of backgrounds

The anisotropic λ -deformed SU(2) model is integrable

The all-loop anisotropic Thirring model interpolates between the WZW model and the non-Abelian T-dual of the anisotropic principal chiral model. We focus on the SU(2) case and we prove that it is classically integrable by providing its Lax pair formulation. We derive its underlying symmetry current algebra and use it to show that the Poisson brackets of the spatial part of the Lax pair, assume the Maillet form. In this way we procure the corresponding r and s matrices which provide non-trivial solutions to the modified Yang–Baxter equation

T-duality transformation of gauged linear sigma model with F-term

We develop the duality transformation rules in two-dimensional theories in the superfield formalism. Even if the chiral superfield which we dualize involves an F-term, we can dualize it by virtue of the property of chiral superfields. We apply the duality transformation rule of the neutral chiral superfield to the N=(4,4) gauged linear sigma model for five-branes. We also investigate the duality transformation rule of the charged chiral superfield in the N=(4,4) gauged linear sigma model for the A1 -type ALE space. In both cases we obtain the dual Lagrangians in the superfield formalism. In the low energy limit we find that their duality transformations are interpreted as T-duality transformations consistent with the Buscher rule

A renormalization group method for studying the early universe in the Lorentzian IIB matrix model

We propose a new method for studying the early universe in the Lorentzian version of the IIB matrix model, which is considered to be a nonperturbative formulation of superstring theory. This method is based on the idea of the renormalization group, and it enables us to study the time-evolution of the universe for a much longer time than in the [S.-W. Kim, J. Nishimura, and A. Tsuchiya, Phys. Rev. Lett. 108 , 011601 (2012)], which showed that the SO(9) rotational symmetry is spontaneously broken down to SO(3) after a critical time. We demonstrate how this method works in a simplified model, which is expected to capture the behaviors of the original model when the space is not so large. In particular, we present clear evidence that the 3D space expands exponentially after the critical time in this simplified model

Natural realization of a large extra dimension in 5D supersymmetric theory

An exponentially large extra dimension can be naturally realized by the Casimir energy and the gaugino condensation in 5D supersymmetric theory. The model does not require any hierarchies among the 5D parameters. The key ingredient is an additional modulus other than the radion, which generically exists in 5D supergravity. SUSY is broken at the vacuum, which can be regarded as the ScherkSchwarz SUSY breaking. We also analyze the mass spectrum and discuss some phenomenological aspects