The maximum entropy method is used to compute the dressed-quark spectral density from the self-consistent numerical solution of a rainbow truncation of QCD’s gap equation at temperatures above that for which chiral symmetry is restored. In addition to the normal and plasmino modes, the spectral function also exhibits an essentially nonperturbative zero mode for temperatures extending to 1.4–1.8 times the critical temperature, $T_c$. In the neighborhood of $T_c$, this long-wavelength mode contains the bulk of the spectral strength and as long as this mode persists, the system may fairly be described as a strongly-coupled state of matter.

We report measurements of the resonance properties of ${\Lambda }_c(2595{)}^{+}$ and ${\Lambda }_c(2625{)}^{+}$ baryons in their decays to ${\Lambda }_c^{+}{\pi }^{+}{\pi }^{-}$ as well as ${\Sigma }_c(2455{)}^{++,0}$ and ${\Sigma }_c(2520{)}^{++,0}$ baryons in their decays to ${\Lambda }_c^{+}{\pi }^{\pm }$ final states. These measurements are performed using data corresponding to $5.2{\mathrm{fb}}^{-1}$ of integrated luminosity from $p\overline{p}$ collisions at $\sqrt{s}=1.96\mathrm{TeV}$, collected with the CDF II detector at the Fermilab Tevatron. Exploiting the largest available charmed baryon sample, we measure masses and decay widths with uncertainties comparable to the world averages for ${\Sigma }_c$ states, and significantly smaller uncertainties than the world averages for excited ${\Lambda }_c^{+}$ states.

Binary neutron-star systems represent one of the most promising sources of gravitational waves. In order to be able to extract important information, notably about the equation of state of matter at nuclear density, it is necessary to have in hand an accurate analytical model of the expected waveforms. Following our recent work [L. Baiotti, T. Damour, B. Giacomazzo, A. Nagar, and L. Rezzolla, Phys. Rev. Lett. 105, 261101 (2010).], we here analyze more in detail two general-relativistic simulations spanning about 20 gravitational-wave cycles of the inspiral of equal-mass binary neutron stars with different compactnesses, and compare them with a tidal extension of the effective-one-body (EOB) analytical model. The latter tidally extended EOB model is analytically complete up to the 1.5 post-Newtonian level, and contains an analytically undetermined parameter representing a higher-order amplification of tidal effects. We find that, by calibrating this single parameter, the EOB model can reproduce, within the numerical error, the two numerical waveforms essentially up to the merger. By contrast, analytical models (either EOB or Taylor-T4) that do not incorporate such a higher-order amplification of tidal effects, build a dephasing with respect to the numerical waveforms of several radians.

We develop the physics of dual kappa Poincare algebra, which we will call dual DSR. First, we show that the dual kappa Poincare algebra is isomorphic to de Sitter algebra and its space-time is essentially de Sitter space-time. Second, we show how to derive the coproduct rule for Beltrami and conformal coordinates of de Sitter space-time. It follows from the current literature on de Sitter relativity that the speed of light $c$ and the de Sitter length are the two invariant scales of the physics of dual kappa Poincare. Third, we derive the first Casimir invariant of the dual kappa Poincare algebra and use this to derive an expression for the speed of light, our fourth result. Fifth, the field equation for the scalar field is derived from the Casimir invariant. The results for the coordinate speed of light and the scalar field theory are the same as in de Sitter theory in the planar coordinate basis. Thus, we have shown that the physics of the dual kappa Poincare algebra (in the dual bicrossproduct basis), which can be appropriately called dual DSR, is essentially de Sitter relativity. Sixth, we argue the existence of an observer-independent minimum momentum. Seventh, we argue heuristically that the existence of minimum momentum will lead to a dual generalized uncertainty principle. Finally, we note that dual DSR is not a quantum theory of space-time but a quantum theory of momenta.

The Wheeler-DeWitt (WDW) equation for the Lambda-Kantowski-Sachs model can also be understood as the WDW-equation corresponding to the Schwarzschild-(anti)deSitter space-times, due to the well-known diffeomorphism between these two metrics. This equation ignores the coordinate patch one chooses and only by imposing coordinate conditions will it be possible to distinguish between black hole or cosmological models. At that point, the foliation parameter $t$ or $r$ will appear in the solution of interest. In this work we supersymmetrize this WDW-equation obtaining an extra term in the potential with two possible signs. We have already, in a similar manner, proposed and analyzed a supersymmetric generalization of a Schwarzschild black hole. The WKB method is then applied, given rise to four classical equations, two for the Schwarzschild-deSitter space-time and another two for the Schwarzschild-anti-deSitter space-time. One can then study the asymptotic cases in which one of two potential terms arising in each Hamiltonian, for each of these space-times, dominates the behavior. One of these limiting (bosonic) cases gives the usual Schwarzschild-(anti)deSitter space-times. We will study here the other four asymptotic regions; they provide six solutions. For the Schwarzschild-deSitter space-time we get two solutions which have singularities at $r=0$ and $r_0^s$, and depending on an integration constant $C$ and the sign at the potential due to these SUSY region, they can also present another two singularities in $r_h^s$ and $r_c^s$. For the Schwarzschild-anti-deSitter space-time the solutions have a singularity at $r=0$ and depending on the integration constant and the sign of the SUSY potential another singularity can appear at $r_{+}$. We find associated masses and, based on the holographic principle, we find also the entropies for the bosonic region, which coincide with the ones obtained by the usual methods. We apply this same procedure to get entropies associated to the supersymmetric asymptotic solutions. Even though we were unable to obtain the complete solution to the model, it is shown that horizons can never be reached because when one would approach the standard horizons (the bosonic region), the relevant term in the potential is the one due to supersymmetry and as mentioned in this asymptotic limit one does not have horizons but instead singularities.

The future space-based gravitational wave detector LISA will be able to measure parameters of coalescing massive black hole binaries, often to extremely high accuracy. Previous work has demonstrated that the black hole spins can have a strong impact on the accuracy of parameter measurement. Relativistic spin-induced precession modulates the waveform in a manner which can break degeneracies between parameters, in principle significantly improving how well they are measured. Recent studies have indicated, however, that spin precession may be weak for an important subset of astrophysical binary black holes: those in which the spins are aligned due to interactions with gas. In this paper, we examine how well a binary’s parameters can be measured when its spins are partially aligned and compare results using waveforms that include higher post-Newtonian harmonics to those that are truncated at leading quadrupole order. We find that the weakened precession can substantially degrade parameter estimation. This degradation is particularly devastating for the extrinsic parameters sky position and distance. Absent higher harmonics, LISA typically localizes the sky position of a nearly aligned binary a factor of $\sim 6$ less accurately than for one in which the spin orientations are random. Our knowledge of a source’s sky position will thus be worst for the gas-rich systems which are most likely to produce electromagnetic counterparts. Fortunately, higher harmonics of the waveform can make up for this degradation. By including harmonics beyond the quadrupole in our waveform model, we find that the accuracy with which most of the binary’s parameters are measured can be substantially improved. In some cases, parameters can be measured as well in partially aligned binaries as they can be when the binary spins are random.

We investigate chiral symmetry breaking in strong magnetic fields at finite temperature and densities in a 3 flavor Nambu Jona Lasinio model including the Kobayashi Maskawa ’t Hooft determinant term, using an explicit structure for the ground state in terms of quark-antiquark condensates. The mass gap equations are solved self consistently and are used to compute the thermodynamic potential. We also derive the equation of state for strange quark matter in the presence of strong magnetic fields which could be relevant for proto-neutron stars.

Using the de Sitter/quantum field theory correspondence in the context of inflation allows for the study of interesting, otherwise inaccessible physics. In particular, by studying inflation via its dual field theory at the boundary of the de Sitter space, it may be possible to study a regime of strongly coupled gravity at early times. The purpose of this work is to completely express cosmological observables in terms of the free parameters of a dual field theory and to compare them with cosmic microwave background data. In this way, constraints on the observational parameters constrains the validity of the strongly coupled inflation picture by imposing limits on the parameters of the field theory. The fit with data defines a limit for the consistency and validity of the approach taken and shows that, within this limit, the model is almost unconstrained, but quite predictive, producing power spectra of density perturbations extremely near scale invariance.

We derive all single-field cosmologies with unit sound speed that generate scale invariant curvature perturbations on a dynamical attractor background. We identify three distinct phases: slow-roll inflation; a slowly contracting adiabatic ekpyrotic phase, described by a rapidly varying equation of state; and a novel adiabatic ekpyrotic phase on a slowly expanding background. All of these yield identical power spectra. The degeneracy is broken at the 3-point level: unlike the nearly Gaussian spectrum of slow-roll inflation, adiabatic ekpyrosis predicts large non-Gaussianities on small scales.

Conditions for the existence of repeatable light paths (RLPs) in the shearfree normal cosmological models are investigated. It is found that in the conformally nonflat models the only RLPs are radial null geodesics (in the spherical case) and their analogues in the plane and hyperbolically symmetric cases. In the conformally flat Stephani models, there exist special spherically, plane, and hyperbolically symmetric subcases, in which all null geodesics are RLPs. They are slightly more general than the Friedmann-Lemaître-Robertson-Walker models of the corresponding symmetries: their curvature index function $k(t)$ and the scale factor $R(t)$ are expressed through a single function of time. In addition to that, there exist special cases of the Stephani solution in which some of the null geodesics are RLPs. All these special cases are identified.

We introduce a $CP$-violating coupling between the Ricci curvature and the heavy right-handed neutrinos. This splits the Majorana masses of the left- and the right-handed heavy neutrinos. When the heavy neutrinos decay, their decay rates are different into left and right chirality light neutrinos. A time-varying nonzero Ricci curvature can give rise to a net lepton asymmetry. The source of a nonzero curvature in a radiation era is the quantum fluctuations of primordial fields.

We consider a cosmological scenario in which a scale-invariant spectrum of curvature perturbations is generated by a rapidly evolving equation of state on a slowly expanding background. This scenario generalizes the “adiabatic ekpyrotic” mechanism proposed recently by Khoury and Steinhardt [Phys. Rev. Lett. 104, 091301 (2010)]. Whereas the original proposal assumed a slowly contracting background, the present work shows that the mechanism works equally well on an expanding background. This greatly expands the realm of broader cosmological scenarios in which this mechanism can be embedded. We present a phase space analysis and show that both the expanding and contracting versions of the scenario are dynamical attractors, with the expanding branch having a broader basin of attraction. In both cases, a finite range of scale-invariant modes can be generated within the regime of validity of perturbation theory.

In this paper we examine whether indirect detection constraints on dark matter associated with a nonthermal history may be significantly improved when accounting for the presence of Galactic substructure in the form of dark matter spikes. We find that significant constraints may be derived from the nonobservation of an excess of diffuse gamma rays and from the properties of bright gamma-ray point sources observed by the Fermi Gamma-Ray Space Telescope, but these constraints depend sensitively on the details of the formation of the first stars and their subsequent black hole remnants. However, we also find that, especially if WIMPs annihilate primarily to quarks or gauge bosons, it is possible to extract meaningful and conservative bounds on the annihilation cross section.

At large baryon number density, it is likely that the ground state of QCD is a color-flavor-locked phase with a $K^0$ condensate. The $\mathrm{CFL}+K^0$ phase is known to support superconducting vortex strings, and it has been previously suggested that it may also support vortons, which are superconducting vortex rings. We reexamine the question of the stability of vortons, taking into account electromagnetic effects, which make leading-order contributions to vorton dynamics but were not investigated in previous work. We find that current-carrying and electrically charged vortons can be stabilized either by their angular momentum, by Coulomb repulsion, or by a combination of both effects.

We consider chiral symmetry breaking AdS/QCD models with cubic and quartic potentials in the scalar sector and a $z$-dependent mass for scalars in the bulk. In these models it is possible to get good mesonic spectra using current quark masses.

We propose a simple testable model with mass generation mechanisms for dark matter and neutrino based on the gauged $U(1{)}_{B\mathrm{\text{−}}L}$ symmetry and an exact $Z_2$ parity. The $U(1{)}_{B\mathrm{\text{−}}L}$ symmetry is spontaneously broken at the TeV scale, by which $Z_2$-odd right-handed neutrinos receive Majorana masses of the electroweak scale. The lightest one is a dark matter candidate, whose stability is guaranteed by the $Z_2$ parity. Resulting lepton number violation is transmitted to the left-handed neutrinos ${\nu }_L^i$ via the loop-induced dimension-six operator. Consequently, the tiny masses of ${\nu }_L^i$ can be generated without excessive fine-tuning. The observed dark matter abundance can be reproduced by the pair annihilation via the $s$-channel scalar exchange due to mixing of neutral components of $\Phi$ and $S$, where $\Phi$ and $S$, respectively, represent the Higgs doublet and the additional scalar singlet with the $B\mathrm{\text{−}}L$ charge. The model can be tested at collider experiments as well as flavor experiments through the discriminative predictions such as two light neutral Higgs bosons with large mixing, invisible decays of the Higgs bosons as well as the $B\mathrm{\text{−}}L$ gauge boson, and lepton flavor violation.

We study the Wigner functions of the nucleon which provide multidimensional images of the quark distributions in phase space. These functions can be obtained through a Fourier transform in the transverse space of the generalized transverse-momentum dependent parton distributions. They depend on both the transverse position and the three-momentum of the quark relative to the nucleon, and therefore combine in a single picture all the information contained in the generalized parton distributions and the transverse-momentum dependent parton distributions. We focus the discussion on the distributions of unpolarized/longitudinally polarized quark in an unpolarized/longitudinally polarized nucleon. In this way, we can study the role of the orbital angular momentum of the quark in shaping the nucleon and its correlations with the quark and nucleon polarizations. The quark orbital angular momentum is also calculated from its phase-space average weighted with the Wigner distribution of unpolarized quarks in a longitudinally polarized nucleon. The corresponding results obtained within different light-cone quark models are compared with alternative definitions of the quark orbital angular momentum, as given in terms of generalized parton distributions and transverse-momentum dependent parton distributions.

We compute the electromagnetic form factors of the nucleon in the Poincaré-covariant Faddeev framework based on the Dyson-Schwinger equations of QCD. The general expression for a baryon’s electromagnetic current in terms of three interacting dressed quarks is derived. Upon employing a rainbow-ladder gluon-exchange kernel for the quark-quark interaction, the nucleon’s Faddeev amplitude and electromagnetic form factors are computed without any further truncations or model assumptions. The form-factor results show clear evidence of missing pion-cloud effects below a photon momentum transfer of $\sim 2{\mathrm{GeV}}^2$ and in the chiral region, whereas they agree well with experimental data at higher photon momenta. Thus, the approach reflects the properties of the nucleon’s quark core.

I present results for the top quark rapidity distribution at Large Hadron Collider and Tevatron energies, including higher-order corrections from threshold resummation. Approximate next-to-next-to-leading-order (NNLO) results are obtained by adding the NNLO soft-gluon corrections at next-to-next-to-leading-logarithm level to the exact next-to-leading-order calculation. Theoretical predictions are shown for the rapidity distribution, including the scale dependence of the distributions. The forward-backward asymmetry at the Tevatron is also calculated.