The early literature on black hole thermodynamics ignored the $P\text{−}V$ term associated with the existence of a fundamental physical constant in the black hole solution. The inclusion of this constant in the first law becomes inconsistent with the Smarr relation. Once the missing $P\text{−}V$ term is introduced, it becomes customary to introduce it only in problems where there is a negative cosmological constant. This practice is inherited from cosmological approaches which consider the quantity $-\mathrm{\Lambda }/8\pi$ as the constant pressure due to a cosmological fluid. However, the notions of pressure and thermodynamic volume in black hole thermodynamics are very different from their counterparts in classical thermodynamics. From this point of view, there is a priori no compelling reason to not extend this notion of pressure and associate a partial pressure with each “external” density ${8\pi T_t}^t$. In this work, we associate a partial pressure with a variable mass parameter as well as with each $tt$ component of the effective stress-energy tensor ${T_{\mathrm{eff}\mu }}^{\nu }$ but not with the linear component of the electromagnetic field. Using the field equations ${G_{\mu }}^{\nu }=8\pi {T_{\mathrm{eff}\mu }}^{\nu }$, we derive universal expressions for the enthalpy, internal energy, free energies, thermodynamic volume, equation of state, law of corresponding states, criticality, and critical exponents of static (nonrotating) charged black holes, with possibly a variable mass parameter, whether they are solutions to the Einstein field equations or not. We extend the derivation to the case where the black hole is immersed in the field of a quintessence force and to the multiforce case. Many applications and extensions are considered, including applications to regular black holes derived in previous and present work. No inconsistency has been noticed in their thermodynamics.

In previous publications we have proposed that inflation can be realized in a second minimum of the standard model Higgs potential at energy scales of about $10^{16}\mathrm{GeV}$, if the minimum is not too deep and if a mechanism which allows a transition to the radiation dominated era can be found. This is provided, e.g., by scalar-tensor gravity models or hybrid models. Using such ideas we had predicted the Higgs boson mass to be of about $126\pm 3\mathrm{GeV}$, which has been confirmed by the LHC, and that a possibly measurable amount of gravity waves should be produced. Using more refined recent theoretical calculations of the renormalization group equations we show that such scenario has the right scale of inflation only for small Higgs mass, lower than about 124 GeV, otherwise gravity waves are overproduced. The precise value is subject to some theoretical error and to experimental errors on the determination of the strong coupling constant. Finally we show that introducing a moderately large nonminimal coupling for the Higgs field the bound can shift to larger values and be reconciled with the LHC measurements of the Higgs mass.

Recent determinations of the equation of state of dark energy hint that this may well be of the phantom type, i.e., $w_{de}<-1$. If confirmed by future experiments, this would strongly point to the existence of fields that violate the dominant energy condition, which are known to present serious theoretical difficulties. This paper presents an alternative to this possibility, namely, that the measured equation of state, $w_{de}$, is in reality an effective one, the equation of state of the quantum vacuum, $w_{\mathrm{\Lambda }}=-1$, plus the negative equation of state, $w_c$, associated to the production of particles by the gravitational field acting on the vacuum. To illustrate this, three phenomenological models are proposed and constrained with recent observational data.

The basic constituent of interferometric gravitational wave detectors—the test-mass-to-test-mass interferometric link—behaves as a differential dynamometer measuring effective differential forces, comprising an integrated measure of gravity curvature, inertial effects, as well as nongravitational spurious forces. This last contribution is going to be characterized by the LISA Pathfinder mission, a technology precursor of future space-borne detectors like eLISA. Changing the perspective from displacement to acceleration can benefit the data analysis of LISA Pathfinder and future detectors. The response in differential acceleration to gravitational waves is derived for a space-based detector’s interferometric link. The acceleration formalism can also be integrated into time delay interferometry by building up the unequal-arm Michelson differential acceleration combination. The differential acceleration is nominally insensitive to the system’s free evolution dominating the slow displacement dynamics of low-frequency detectors. Working with acceleration also provides an effective way to subtract measured signals acting as systematics, including the actuation forces. Because of the strong similarity with the equations of motion, the optimal subtraction of systematic signals, known within some amplitude and time shift, with the focus on measuring the noise provides an effective way to solve the problem and marginalize over nuisance parameters. The $\mathcal{F}$ statistic, in widespread use throughout the gravitation waves community, is included in the method and suitably generalized to marginalize over linear parameters and noise at the same time. The method is applied to LPF simulator data and, thanks to its generality, can also be applied to the data reduction and analysis of future gravitational wave detectors.

We propose a model with a real $SU(2)$ triplet fermion and a sterile neutrino, both of which are odd under a conserved ${\mathbb{Z}}_2$ symmetry. With all new physics confined to the ${\mathbb{Z}}_2$-odd sector, whose low energy manifestation is in some higher-dimensional operators, a fermionic dark matter candidate is found to emerge. We identify the region of the parameter space of the scenario, which is consistent with all constraints from relic density and direct searches, and allows a wide range of masses for the dark matter candidate.

We consider the $\mathrm{SU}(3{)}_C\otimes \mathrm{SU}(3{)}_L\otimes \mathrm{U}(1{)}_X\otimes \mathrm{U}(1{)}_N$ (3-3-1-1) model at the grand unified theory scale with implication for inflation and leptogenesis. The mass spectra of the neutral Higgs bosons and neutral gauge bosons are reconsidered when the scale of the 3-3-1-1 breaking is much larger than that of the ordinary $\mathrm{SU}(3{)}_C\otimes \mathrm{SU}(3{)}_L\otimes \mathrm{U}(1{)}_X$ (3-3-1) breaking. We investigate how the 3-3-1-1 model generates an inflation by identifying the scalar field that spontaneously breaks the $\mathrm{U}(1{)}_N$ symmetry to inflaton as well as including radiative corrections for the inflaton potential. We figure out the parameter spaces appeared in the inflaton potential that satisfy the conditions for an inflation model and obtain the inflaton mass an order of ${10}^{13}\mathrm{GeV}$. The inflaton can dominantly decay into a pair of light Higgs bosons or a pair of heavy Majorana neutrinos which lead, respectively, to a reheating temperature of ${10}^9\mathrm{GeV}$ order appropriate to a thermal leptogenesis scenario or to a reduced reheating temperature corresponding to a nonthermal leptogenesis scenario. We calculate the lepton asymmetry which yields baryon asymmetry successfully for both the thermal and nonthermal cases.

We calculate an $s$-wave amplitude matrix for all the possible two-to-two body scalar boson elastic scatterings in models with three scalar doublets, including contributions from the longitudinal component of weak gauge bosons via the equivalence theorem approximation. Specifically, we concentrate on the two cases with two(one) active plus one(two) inert doublet fields, referred to as $\mathrm{I}(1+2)\mathrm{HDM}[\mathrm{I}(2+1)\mathrm{HDM}]$, under $CP$ conservation. We obtain three analytically irreducible submatrices with the $3\times 3$ form and 18 eigenvalues for the amplitude matrix as an independent set, where the same formula can be applied to both models. By requiring a perturbative unitarity condition, we can constrain the magnitude of quartic coupling constants in the Higgs potential. This constraint, in particular in the $\mathrm{I}(1+2)\mathrm{HDM}$, can be translated into a bound on masses of extra active scalar bosons. Furthermore, when Standard Model-like Higgs boson couplings with weak gauge bosons are deviated from the Standard Model predictions, the unitarity condition provides an upper limit on the masses. We find that stronger upper bounds on the masses of the active $CP$-even and $CP$-odd Higgs bosons are obtained under the constraints from the unitarity and vacuum stability conditions, as well as the electroweak $S$, $T$ and $U$ parameters, as compared to those in two-Higgs doublet models with a softly broken $Z_2$ symmetry.

The zero-degree calorimeters (ZDC) installed in the ALICE, ATLAS and CMS experiments at the LHC make possible simultaneous detection of forward-backward leading neutrons, $pp\to nXn$. Such data with sufficiently high statistics could be a source of information about the pion-pion total cross section at high energies, provided that the absorption corrections, which are expected to be strong, are well understood. Otherwise, making a plausible assumption about the magnitude of the pion-pion cross section, one can consider such measurements as a way to study the absorption effects, which is the main focus of the present paper. These effects introduced at the amplitude level are found to be different for the pion fluxes, which either conserve or flip the nucleon helicity. The pion fluxes from both colliding protons are essentially reduced by absorption; moreover, there is a common absorption suppression factor, which breaks down the factorized form of the cross section. We also evaluate the feed-down corrections related to the initial/final state inelastic processes possessing a rapidity gap, and found them to be small in the kinematic range under consideration. The contribution of other isovector Reggeons, spin-flip natural parity $\rho$ and $a_2$ and spin-nonflip unnatural parity $a_1$, are also evaluated and found to be rather small.

The forward LHCb acceptance offers the possibility of measuring the top-quark pair asymmetry in a kinematic region that does not receive overwhelming dilution from the symmetric gluon-fusion channel. To investigate this possibility, two leptonic final states are identified, and analysis strategies are proposed for each channel with 14 TeV data. Leading fixed-order predictions are then provided for the relevant leptonic asymmetry variables in each channel. If backgrounds can be experimentally constrained, statistically, a nonzero asymmetry is estimated to be observable beyond $5\sigma$ confidence level with the full LHCb 14 TeV data.

Using global fits of valence $u$ and $d$ quark parton distributions and data on quark and nucleon form factors in the Euclidean region, we derive a light-front quark model for the nucleon structure consistent with quark counting rules.

We investigate the reaction ${\pi }^{-}p\to D^{-}{\mathrm{\Lambda }}_c^{+}$ within the generalized parton picture. The process is described by a handbag-type mechanism with the charm-quark mass acting as the hard scale. As in the case of preceding work on $\overline{p}p\to {\overline{\mathrm{\Lambda }}}_c^{-}{\mathrm{\Lambda }}_c^{+}$ we assume that the process amplitude factorizes into one for the perturbatively calculable partonic subprocess $\overline{u}u\to \overline{c}c$ and hadronic matrix elements that can be parametrized in terms of generalized parton distributions. Modeling the generalized parton distributions by overlaps of (valence-quark) light-cone wave functions for the hadrons involved, we obtain numerical results for unpolarized differential and integrated cross sections as well as spin observables. Our approach works well above the production threshold ($s\gtrsim 20{\mathrm{GeV}}^2$) in the forward hemisphere and predicts unpolarized cross sections of the order of nb, a finding that could be of interest in view of plans to measure ${\pi }^{-}p\to D^{-}{\mathrm{\Lambda }}_c^{+}$ at J-PARC.

We present an attempt using the maximum entropy principle to determine valence quark distributions in the proton at a very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of parton distribution functions. The maximum entropy method is expected to be particularly useful in cases where relatively little information from QCD theory is given.

A systematic analysis of transverse momentum and rapidity distributions measured in high-energy proton-proton ($pp$) collisions for energies ranging from 53 GeV to 7 TeV using Tsallis thermodynamics is presented. The reasonable description of all transverse momentum spectra obtained in earlier analyses is confirmed and extended. All energies can be described by a single Tsallis temperature of $68\pm 5\mathrm{MeV}$ at all beam energies and particle types investigated (43 in total). The value of the entropic index, $q$, shows a wider spread but is always close to $q\approx 1.146$. These values are then used to describe the rapidity distributions using a superposition of two Tsallis fireballs along the rapidity axis. It is concluded that the hadronic system created in high-energy $pp$ collisions between 53 GeV and 7 TeV can be seen as obeying Tsallis thermodynamics.

An inclusive search for supersymmetry in events with at least one $b$-tagged jet is performed using proton-proton collision data collected by the CMS experiment in 2012 at a center-of-mass energy of 8 TeV. The data set size corresponds to an integrated luminosity of $19.3{\mathrm{fb}}^{-1}$. The two-dimensional distribution of the razor variables ${\mathrm{R}}^2$ and $M_{\mathrm{R}}$ is studied in events with and without leptons. The data are found to be consistent with the expected background, which is modeled with an empirical function. Exclusion limits on supersymmetric particle masses at a 95% confidence level are derived in several simplified supersymmetric scenarios for several choices of the branching fractions. By combining the likelihoods of a search in events without leptons and a search that requires a single lepton (electron or muon), an improved bound on the top-squark mass is obtained. Assuming the lightest supersymmetric particle to be stable and weakly interacting, and to have a mass of 100 GeV, the branching-fraction-dependent (-independent) production of gluinos is excluded for gluino masses up to 1310 (1175) GeV. The corresponding limit for top-squark pair production is 730 (645) GeV.

We investigate the spectral dimension of $\kappa$-spacetime using the $\kappa$-deformed diffusion equation. The deformed equation is constructed for two different choices of Laplacians in $n$-dimensional, $\kappa$-deformed Euclidean spacetime. We use an approach where the deformed Laplacians are expressed in the commutative spacetime itself. Using the perturbative solutions to diffusion equations, we calculate the spectral dimension of $\kappa$-deformed spacetime and show that it decreases as the probe length decreases. By introducing a bound on the deformation parameter, spectral dimension is guaranteed to be positive definite. We find that, for one of the choices of the Laplacian, the noncommutative correction to the spectral dimension depends on the topological dimension of the spacetime whereas for the other, it is independent of the topological dimension. We have also analyzed the dimensional flow for the case where the probe particle has a finite extension, unlike a point particle.

We consider a 2-dimensional conformal field theory (CFT) obtained from twisted compactification of the 4-dimensional $\mathcal{N}=4$ super Yang-Mills theory on a Riemann surface with a boundary. We find the boundary conditions for preserving some of the supersymmetry. In particular, an $\mathcal{N}=(2,2)$ superconformal field theory is obtained from supersymmetry breaking due to the boundary from $\mathcal{N}=(4,4)$. In this case we calculate the central charge of the CFT and show its dependence on the topology of the Riemann surface.

We analyze the consequences of the recently found generalization of the Christodoulou-Ruffini black hole mass decomposition for Einstein-Born-Infeld black holes [characterized by the parameters $(Q,M,b)$, where $M=M(M_{\text{irr}},Q,b)$, $b$ scale field, $Q$ charge, $M_{\text{irr}}$ “irreducible mass,” physically meaning the energy of a black hole when its charge is null] and their interactions. We show in this context that their description is largely simplified and can basically be split into two families depending upon the parameter $b|Q|$. If $b|Q|\le 1/2$, then black holes could have even zero irreducible masses and they always exhibit single nondegenerated horizons. If $b|Q|>1/2$, then an associated black hole must have a minimum irreducible mass (related to its minimum energy) and has two horizons up to a transitional irreducible mass. For larger irreducible masses, single horizon structures raise again. By assuming that black holes emit thermal uncharged scalar particles, we further show in light of the black hole mass decomposition that one satisfying $b|Q|>1/2$ takes an infinite amount of time to reach the zero temperature, settling down exactly at its minimum energy. Finally, we argue that depending on the fundamental parameter $b$, the radiation (electromagnetic and gravitational) coming from Einstein-Born-Infeld black holes could differ significantly from Einstein-Maxwell ones. Hence, it could be used to assess such a parameter.

We revisit the calculation of matter quantum effects on the graviton self-energy on a flat Minkowski background, with the aim to acquire a deeper understanding of the mechanism that renders the graviton massless. To this end, we derive a low-energy theorem which directly relates the radiative corrections of the cosmological constant to those of the graviton mass to all orders in perturbation theory. As an illustrative example, we consider an Abelian Higgs model with minimal coupling to gravity and show explicitly how a suitable renormalization of the cosmological constant leads to the vanishing of the graviton mass at the one-loop level. In the same Abelian Higgs model, we also calculate the matter quantum corrections to the Newtonian potential and present analytical formulas in terms of modified Bessel and Struve functions of the particle masses in the loop. We show that the correction to the Newtonian potential exhibits an exponential fall-off dependence on the distance $r$, once the nonrelativistic limit with respect to the nonzero loop mass is carefully considered. For massless scalars, fermions, and gauge bosons in the loops, we recover the well-known results presented in the literature.

The three-dimensional volume inside a spherical black hole can be defined by extending an intrinsic flat-spacetime characterization of the volume inside a two-sphere. For a collapsed object, the volume grows with time since the collapse, reaching a simple asymptotic form, has a compelling geometrical interpretation. Perhaps surprisingly, it is large. The result may have relevance for the discussion on the information paradox.

In this paper, we obtain topological black hole solutions of third-order Lovelock gravity coupled with two classes of Born-Infeld-type nonlinear electrodynamics with anti–de Sitter asymptotic structure. We investigate geometric and thermodynamics properties of the solutions and obtain conserved quantities of the black holes. We examine the first law of thermodynamics and find that the conserved and thermodynamic quantities of the black hole solutions satisfy the first law of thermodynamics. Finally, we calculate the heat capacity and determinant of the Hessian matrix to evaluate thermal stability in both canonical and grand canonical ensembles. Moreover, we consider the extended phase space thermodynamics to obtain a generalized first law of thermodynamics as well as the extended Smarr formula.