Narrow Results

We review our recent relativistic generalization of the Gutzwiller–Duistermaat–Guillemin trace formula and Weyl law on globally hyperbolic stationary space-times with compact Cauchy hypersurfaces. We also discuss anticipated generalizations to non-compact Cauchy hypersurface cases.

In this paper, we use spinorial method to define a new quasi-local mass with reference to a Schwarzchild manifold. In the proof of the main theorem, spinors are defined on manifold with two boundary components. Through the Reilly formula, we get the new quasi-local mass is nonnegative. Combined with Riemannian–Penrose inequality, we derive a localized Penrose inequality.

During the last couple of years astronomers and astrophysicists have been debating on the fact whether the so-called "strange stars" — stars made up of strange quark matter, have been discovered with the candidates like SAX J1808.4–3658, 4U 1728–34, RX J1856.5–3754, etc. The main contention has been the estimation of radius of the star for an assumed mass of ~ 1.4 M_⊙ and to see whether the point overlaps with the graphs for the neutron star equation of state or whether it goes to the region of stars made of strange matter equation of state. Using the well-established formulae from general relativity for the gravitational redshift and the "lensing effect" due to bending of photon trajectories, we, in this letter, relate the parameters M and R with the observable parameters, the redshift z and the radiation radius R_∞, thus constraining both M and R for specific ranges, without any other arbitrariness. With the required inputs from observations, one ought to incorporate the effects of self-lensing of the compact stars which has been otherwise ignored in all of the estimations done so far. Nonetheless, these effects of self-lensing make a marked difference for constraints on the M–R relation.

In the framework of meson–meson mixing, in the presence of the a₄(2040), and f₄(2050) being the 1 ³F₄ states, we suggest that the f′₄, the ninth member of the 1 ³F₄ meson nonet, has a mass of about 2084 MeV, and some predictions on the f₄ and f′₄ decaying into two photons and pseudoscalar mesons are presented. Also, the mass of the lowest lying 4⁺⁺ glueball is predicted to be about 3.15 GeV by using the meson-glueball mass relation derived from the glueball dominance picture, which is in agreement with 3.42 GeV, the average value of the recent predicted results was given by lattice QCD, potential model, semi-relativistic potential model and quasi-particle model.

Present experimental data from neutrino oscillations have provided much information about the neutrino mixing angles. Since neutrino oscillations only determine the mass squared differences , the absolute values for neutrino masses m_i, can not be determined using data just from oscillations. In this work we study implications on neutrino masses from a geometric mean mass relation which enables one to determined the absolute masses of the neutrinos. We find that the central values of the three neutrino masses and their 2σ errors to be m₁ = (1.58 ± 0.18)meV, m₂ = (9.04 ± 0.42)meV, and m₃ = (51.8 ± 3.5)meV. Implications for cosmological observation, beta decay and neutrinoless double beta decays are discussed.

We discuss the gauge dependence of fermion mass definition under the on-shell and pole mass renormalization prescriptions. By the two-loop-level calculation of the cross section of the physical process , we prove for the first time that the on-shell fermion mass renormalization prescription makes physical result gauge-dependent. On the other hand, such gauge dependence does not appear in the result of the pole mass renormalization prescription. Our calculation also implies that the difference of physical results between the two mass renormalization prescriptions cannot be neglected at two-loop level.

A regular wormhole solution in gravity coupled with a phantom scalar and electromagnetic fields is found. The solution exists for a special choice of the parameter f of the potential term. The mass m of a wormhole filled with a phantom and electrostatic fields is calculated. It is shown that close to some point f₀, a small value of the mass m is the remainder of two large masses of the phantom and electrostatic fields. The connection with the renormalization procedure in quantum filed theory is considered. The connection between Wheeler's idea "mass without mass" and renormalization procedure in quantum field theory is discussed.

We investigate a squark cascade decay, i.e. . It is shown that some information on the mass and spin of the supersymmetric particles might be obtained from the cascade decay chain at the Large Hadron Collider at CERN.

This review gives some recollections on the recent history of the concepts of vacuum and mass and the search for higgs. According to the widely spread terminology, the Higgs field permeates vacuum and serves as the origin of masses of all fundamental particles including the Higgs boson — the higgs.

This review presents the world's most precise measurement of the W-boson mass m_W using data corresponding to ≈ 2.2 fb^-1 integrated luminosity collected with the CDF II detector at Fermi National Accelerator Laboratory (Fermilab). With samples of 470,126 W → eν candidates and 624,708 W → μν candidates, m_W is measured to be 80387±12_stat ± 15_syst = 80387 ± 19 MeV [Phys. Rev. Lett.108, 151803 (2012)]. This result significantly exceeds the precision of all previous measurements and improves the world averaged precision by 30%.

In this paper, we apply the method of QCD sum rules to study the doubly heavy tetraquark states $QQ\bar{q}\bar{n}$ with spin-parity $J^P=1^{+}$ and strangeness $S=0,-1$ using careful estimates of the Borel and threshold parameters involved. Masses of the doubly bottom and charmed tetraquarks with isospin $I=0,1/2,1$ are computed precisely via taking into account multifarious condensates up to dimension 10. Compared with the two-heavy meson thresholds, we find that all nonstrange doubly-bottom tetraquarks and a doubly-charmed tetraquarks associated with $J_3$ with $J^P=1^{+}$ are stable against strong decay into two bottom mesons while a doubly-charmed tetraquark associated with current $J_2$ is unstable against strong decay. By the way, weak decay widths of the doubly bottom tetraquarks are also given.

In this paper, we consider a heavy quarkonium state in a hot QCD medium, namely the ground state of charmonium and bottomonium. The quark–antiquark potential is proposed in the form of a temperature-dependent Cornell potential, and is extended to include a temperature-dependent parameter. Then, for the proposed potential with different parametrizations of the Debye mass, the N-dimensional Schrödinger equation is analytically solved using the biconfluent Heun equation. The obtained energy eigenvalues and wave functions are employed to study the flavor dependence, the effect of dimensionality and the influence of the additional term on the mass and binding energy of 1S state of charmonium and bottomonium at finite temperature. The findings of this research are compared to those from past studies. We concluded that this work provides a simple and consistent description of quarkonium states at finite temperature in a hot QCD medium, highlighting the effect of noncompact extra dimensions and the flavor dependence of the binding energies of heavy quarkonia.

The neglected 35 MeV/c² particle mass quantization hypothesis has recently been reassessed for all known meson states. The rule is found to be statistically relevant, once the states are grouped by quark composition and J^PC, with slightly different mass units for each group. In certain groups the mass unit is spin-dependent. Also the mass units are linearly quantized, with highly structured correlation patterns. The baryon masses are organized along similar lines. These results support an indication that hadrons might be shell-structured.

Quark-lepton symmetry invites consideration of the existence of sterile neutrinos. Long ago, we showed that this approach predicts large neutrino mixing amplitudes. Using a Weyl spinor approach, we show, in an analytic example, how this, and pseudo-Dirac pairing, can develop within a reduced rank version of the conventional see-saw mechanism, from small intrinsic mixing strengths. We show by numerical examples that mixing of active and sterile neutrinos can affect the structure of oscillations relevant to extraction of neutrino mixing parameters from neutrino oscillation data.

Using the AdS/CFT correspondence, we study the anisotropic charge transport properties of both supersymmetric and nonsupersymmetric matter fields on (2+1)-dimensional defects coupled to a (3+1)-dimensional "heat bath." We focus on the cases of a finite external background magnetic field, finite net charge density and finite mass and their combinations. In this context, we also discuss the limitations due to operator mixing that appears in a few situations and that we ignore in our analysis. At high frequencies, we discover a spectrum of quasiparticle resonances due to the magnetic field and finite density and at small frequencies, we perform a Drude-like expansion around the DC limit. Both of these regimes display many generic features and some features that we attribute to strong coupling, such as a minimum DC conductivity and an unusual behavior of the "cyclotron" and plasmon frequencies, which become related to the resonances found in the conformal case in an earlier paper. We further study the hydrodynamic regime and the relaxation properties, from which the system displays a set of different possible transitions to the collisionless regime. The mass dependence can be cast in two regimes: a generic relativistic behavior dominated by the UV and a nonlinear hydrodynamic behavior dominated by the IR. In the massless case, we furthermore extend earlier results from the literature to find an interesting selfduality under a transformation of the conductivity and the exchange of density and magnetic field.

The observational evidence of a cosmological constant Λ raises natural questions. Is Λ a universal constant fixing the geometry of an empty universe, as fundamental as the Planck constant or the speed of light in the vacuum? Its natural place is then on the left-hand side of the Einstein equation. Is it instead something emerging from a perturbation calculation performed on the metric g_μν solution of the Einstein equation and to which it might be given a material status of (dark or bright) "energy"? It should then be part of the content of the right-hand side of the Einstein equations. The purpose of this paper is to analyze some of the arguments in favor of each one of these interpretations of the cosmological constant. Recent estimates based on observational data give a bound on the graviton mass to be about 100 Mpc^-1. If this value and the current estimate on the cosmological constant Λ are put into perspective, one faces the interesting coincidence that between the Compton wavelength of the graviton and the cosmological constant there exists the relation . Since a physical quantity like mass originates in a minkowskian conservation law, we proceed with a group theoretical interpretation of this relation in terms of the two possible Λ-deformations of the Poincaré group, namely the de Sitter and anti de Sitter groups. We use a very suitable formula, the so-called Garidi mass, and the typically dS/AdS dimensionless parameter ħH/mc² in order to make clear the asymptotic relations between minkowskian masses m and their possible dS/AdS counterparts. We conclude that if the fundamental state of the geometry of space-time is minkowskian, then the square of the mass of the graviton is proportional to Λ; otherwise, if the fundamental state is de Sitter, then the graviton is massless in the deSitterian sense.

As one of the most important parameters in the Standard Model (SM), the mass of the W boson (m_W) is currently the limiting factor in our ability to tighten the constraint on the mass of the Higgs boson (m_H) within the SM framework. This review summarizes the world's most precise m_W measurement to date using ~2.2 fb^-1 data collected in collisions at with the CDF II detector at the Fermilab Tevatron Collider. This review will first describe the motivation for improving the precision of m_W measurement, then present the details of this analysis, followed by the final measurement result and the future perspective.

In the last two decades experiments have established the existence of neutrino oscillations and most of the related parameters have by now been measured with reasonable accuracy. These results have accomplished a major progress for particle physics and cosmology. At present neutrino physics is a most vital domain of particle physics and cosmology and the existing open questions are of crucial importance. We review the present status of the subject, the main lessons that we have learnt so far and discuss the great challenges that remain in this field.

The masses and decay constants of the light tensor mesons were calculated with quantum numbers $J^P=2^{+}$ in the framework of the QCD sum rules in the standard model. The non perturbative contributions up to dimension-5 are considered as important terms of the operator product expansion.

In this paper, we study the dominant nonuniversal contributions to muon decay for the five scalar leptoquarks (LQs) allowed by the Standard Model gauge symmetries. By using a common computational framework, we isolate the New-Physics (NP) one-loop corrections over the observable $\mathrm{\Delta }r$ and explore the connection with the W boson mass. We highlight the role of nonuniversal terms considering, for the $\mathrm{\text{SU}}(2)$ doublet and triplet LQs, a completely degenerate scenario, thus cancelling/moderating the effects of the oblique parameters S, T and U. We determine simple formulas that exhibit the leading nonuniversal behavior generated by the introduction of extra Yukawa terms and confront them against a present tension in $M_W$ and the projected FCC-ee accuracy.