In a theory where the cosmological constant $\Lambda$ or the gauge coupling constant $g$ arises as the vacuum expectation value, its variation should be included in the first law of thermodynamics for black holes. This becomes $dE=TdS+{\Omega }_{i}d{J}_i+{\Phi }_{\alpha }d{Q}_{\alpha }+\Theta d\Lambda$, where $E$ is now the enthalpy of the spacetime, and $\Theta$, the thermodynamic conjugate of $\Lambda$, is proportional to an effective volume $V=-\frac{16\pi \Theta }{D-2}$ “inside the event horizon.” Here we calculate $\Theta$ and $V$ for a wide variety of $D$-dimensional charged rotating asymptotically anti-de Sitter (AdS) black hole spacetimes, using the first law or the Smarr relation. We compare our expressions with those obtained by implementing a suggestion of Kastor, Ray, and Traschen, involving Komar integrals and Killing potentials, which we construct from conformal Killing-Yano tensors. We conjecture that the volume $V$ and the horizon area $A$ satisfy the inequality $R\equiv ((D-1)V/{\mathcal{A}}_{D-2}{)}^{1/(D-1)}({\mathcal{A}}_{D-2}/A{)}^{1/(D-2)}\ge 1$, where ${\mathcal{A}}_{D-2}$ is the volume of the unit ($D-2$) sphere, and we show that this is obeyed for a wide variety of black holes, and saturated for Schwarzschild-AdS. Intriguingly, this inequality is the “inverse” of the isoperimetric inequality for a volume $V$ in Euclidean ($D-1$) space bounded by a surface of area $A$, for which $R\le 1$. Our conjectured reverse isoperimetric inequality can be interpreted as the statement that the entropy inside a horizon of a given ”volume” $V$ is maximized for Schwarzschild-AdS. The thermodynamic definition of $V$ requires a cosmological constant (or gauge coupling constant). However, except in seven dimensions, a smooth limit exists where $\Lambda$ or $g$ goes to zero, providing a definition of $V$ even for asymptotically flat black holes.

It is argued that whereas the Shatskiy single rings produced by the gravitational inner field of a spherically symmetric wormhole and the concentric double Einstein rings generated by a toroidal ringhole could not be used without some uncertainty to identify the presence of such tunnelings in the universe or the existence of a parallel universe, the image which the inner gravitational field of a nonorientable Klein-bottle hole tunneling would leave by lensing a single luminous source is that of a truncated double spiral, which is a signature that cannot be attributed to any other single or composite astronomical object in whichever universe it may be placed. In this report we argue some more reasons to predict that such a signature would imply the discovery of one such nonorientable tunneling in our or other universe. After all, a nonorientable Klein-bottle hole is also a perfectly valid solution to the Einstein equations, and the stuff which would make it feasible is becoming more and more familiar in cosmology.

The increase of the measured hadronic total cross sections at the highest energies is empirically described by the squared log of center-of-mass energy $\sqrt{s}$ as ${\sigma }_{\mathrm{tot}}\simeq B{log}^{2}s$, consistent with the energy dependence of the Froissart unitarity bound. The coefficient $B$ is argued to have a universal value, but this is not proved directly from QCD. In the previous tests of this universality, the $p(\overline{p})p$, ${\pi }^{\mp }p$, and $K^{\mp }p$ forward scatterings were analyzed independently and found to be consistent with $B_{pp}\simeq B_{\pi p}\simeq B_{Kp}$, although the determined value of $B_{Kp}$ had large uncertainty. In the present work, we have further analyzed forward $K^{\mp }p$ scattering to obtain a more exact value of $B_{Kp}$. Making use of continuous-moment sum rules we have fully exploited the information of low-energy scattering data to predict the high-energy behavior of the amplitude through duality. The estimation of $B_{Kp}$ is improved remarkably, and our result strongly supports the universality of $B$.

We study the single transverse-spin asymmetry for the inclusive open-charm production in the $pp$-collision, $p^{\uparrow }p\to DX$, induced by the three-gluon correlation functions in the polarized nucleon. We derive the corresponding twist-3 cross section formula in the leading order with respect to the QCD coupling constant. As in the case of the semi-inclusive deep inelastic scattering, $e{p}^{\uparrow }\to eDX$, our result differs from the previous result in the literature. We also derive a “master formula” which expresses the twist-3 cross section in terms of the $gg\to c\overline{c}$ hard scattering cross section. We present a model calculation of the asymmetry at the RHIC energy, demonstrating the sensitivity of the asymmetry on the form of the three-gluon correlation functions.

Mass spectra of heavy baryons are calculated in the heavy-quark–light-diquark picture in the framework of the QCD-motivated relativistic quark model. The dynamics of light quarks in the diquark as well as the dynamics of the heavy quark and light diquark in the baryon are treated completely relativistically without application of nonrelativistic $v/c$ and heavy quark $1/m_Q$ expansions. Such an approach allows us to get predictions for the heavy baryon masses for rather high orbital and radial excitations. On this basis the Regge trajectories of heavy baryons for orbital and radial excitations are constructed, and their linearity, parallelism, and equidistance are verified. The relations between the slopes and intercepts of heavy baryons are considered and a comparison of the slopes of Regge trajectories for heavy baryons and heavy-light mesons is performed. All available experimental data on heavy baryons fit nicely to the constructed Regge trajectories. The possible assignment of the quantum numbers to the observed excited charmed baryons is discussed.

The CDF Collaboration recently reported an upper limit on boosted top pair production and noted a significant excess above the estimated background of events with two ultramassive boosted jets. We discuss the interpretation of the measurement and its fundamental implications. In case new physics is involved, the most naive contribution is from a new particle produced with a cross section that is a few times higher than that of the top quark and a sizable hadronic branching ratio. We quantify the resulting tension of a possible larger top pair cross section with the absence of excess found in events with one massive boosted jet and missing energy. The measured planar flow distribution shows deviation from CDF’s Pythia QCD prediction at high planarity, while we find a somewhat smaller deviation when comparing with other Monte Carlo tools. As a simple toy model, we analyze the case of a light gluino with R-parity violation and show that it can be made consistent with the data.

We show that the generalized slow roll approach for calculating the power spectrum where the inflationary slow roll parameters are neither small nor slowly varying can be readily extended to models with noncanonical kinetic terms in the inflaton action. For example, rapid sound speed variations can arise in Dirac-Born-Infeld models with features in the warp factor leading to features in the power spectrum. Nonetheless there remains a single source function for deviations that is simply related to the power spectrum. Empirical constraints on this source function can be readily interpreted in the context of features in the inflaton potential or sound speed.

For type IIB supergravity with a running axio-dilaton, we construct bulk solutions which admit a cosmological background metric of Friedmann-Robertson-Walker type. These solutions include both a dark radiation term in the bulk as well as a four-dimensional (boundary) cosmological constant, while gravity at the boundary remains nondynamical. We holographically calculate the stress-energy tensor, showing that it consists of two contributions: The first one, generated by the dark radiation term, leads to the thermal fluid of $\mathcal{N}=4$ SYM theory, while the second, the conformal anomaly, originates from the boundary cosmological constant. Conservation of the boundary stress-tensor implies that the boundary cosmological constant is time-independent, such that there is no exchange between the two stress-tensor contributions. We then study (de)confinement by evaluating the Wilson loop in these backgrounds. While the dark radiation term favors deconfinement, a negative cosmological constant drives the system into a confined phase. When both contributions are present, we find an oscillating universe with negative cosmological constant which undergoes periodic (de)confinement transitions as the scale of three-space expands and recontracts.

We provide a thorough exposition, including technical and numerical details, of previously published results on the quantum stabilization of cosmic strings. Stabilization occurs through the coupling to a heavy fermion doublet in a reduced version of the standard model. We combine the vacuum polarization energy of fermion zero-point fluctuations and the binding energy of occupied energy levels, which are of the same order in a semiclassical expansion. Populating these bound states assigns a charge to the string. We show that strings carrying fermion charge become stable if the electroweak bosons are coupled to a fermion that is less than twice as heavy as the top quark. The vacuum remains stable in our model, because neutral strings are not energetically favored. These findings suggests that extraordinarily large fermion masses or unrealistic couplings are not required to bind a cosmic string in the standard model.

We consider the scenario where, in a five-dimensional theory, the extra spatial dimension has different scaling than the other four dimensions. We find background maximally symmetric solutions, when the bulk is filled with a cosmological constant and at the same time it has a three-brane embedded in it. These background solutions are reminiscent of Randall-Sundrum warped metrics, with bulk curvature depending on the parameters of the breaking of diffeomorphism invariance. Subsequently, we consider the scalar perturbation sector of the theory and show that it has certain pathologies and the striking feature that in the limit where the diffeomorphism invariance is restored, there remain ghost scalar mode(s) in the spectrum.

We address the properties of self-gravitating domain walls arising from the breaking of an $SU(N)\times Z_2$-symmetric theory. In the particular case of $N=5$, we find that the two classes of stable non-Abelian kinks possible in flat space, that break $SU(5)$ to its maximal subgroups, have an analogue in the gravitational case, and construct the analytical solutions. Localization of fermion fields in different representations of the gauge group in these branes is investigated. It is also shown that non-Abelian gauge fields localization cannot be achieved through interactions with the brane, but that in one of the two classes of kinks this localization can be implemented via the Dvali-Shifman mechanism.

The peeling theorem of general relativity predicts that the Weyl curvature scalars ${\Psi }_n$ ($n=0,\dots ,4$), when constructed from a suitable null tetrad in an asymptotically flat spacetime, fall off asymptotically as $r^{n-5}$ along outgoing radial null geodesics. This leads to the interpretation of ${\Psi }_4$ as outgoing gravitational radiation at large distances from the source. We have performed numerical simulations in full general relativity of a binary black hole inspiral and merger, and have computed the Weyl scalars in the standard tetrad used in numerical relativity. In contrast with previous results [Phys. Rev. D 80, 121502 (2009).], we observe that all the Weyl scalars fall off according to the predictions of the theorem.

We consider a $(1+1)$-dimensional model of general relativity that is based on a geometric theory of gravity due to Nordström. We show that the model can be reinterpreted as a scalar field theory in flat spacetime in which the scalar field couples to the trace of the total energy-momentum tensor, and we use the flat-spacetime interpretation to formulate the initial value problem for the model. We illustrate our results by using computer simulations of the model to obtain several example solutions.

A general diffeomorphism-invariant SU(2) gauge theory is a gravity theory with two propagating polarizations of the graviton. We develop this description of gravity, in particular, for future applications to the perturbative quantization. Thus, the linearized theory, gauge symmetries, and gauge fixing are discussed in detail, and the propagator is obtained. The propagator takes a simple form of that of Yang-Mills theory with an additional projector on diffeomorphism-equivalence classes of connections inserted. In our approach the gravitational perturbation theory takes a rather unusual form in that the Planck length is no longer fundamental.

New massive gravity provides a nonlinear extension of the Fierz-Pauli mass for gravitons in $2+1$ dimensions. Here we construct a Weyl-invariant version of this theory. When the Weyl symmetry is broken, the graviton gets a mass in analogy with the Higgs mechanism. In (anti)-de Sitter backgrounds, the symmetry can be broken spontaneously, but in flat backgrounds radiative corrections, at the two-loop level, break the Weyl symmetry à la Coleman-Weinberg mechanism. We also construct the Weyl-invariant extensions of some other higher-derivative models, such as the Gauss-Bonnet theory (which reduces to the Maxwell theory in three dimensions) and the Born-Infeld type gravities.

We examine the electromagnetic and gravitational wave (GW) signatures of stellar-mass compact objects (COs) spiraling into a supermassive black hole (extreme mass-ratio inspirals), embedded in a thin, radiation-pressure dominated, accretion disk. At large separations, the tidal effect of the secondary CO clears a gap. We derive the conditions necessary for gap opening in a radiation-pressure dominated disk and show that the gap refills during the late GW-driven phase of the inspiral, leading to a sudden electromagnetic brightening of the source. The accretion disk leaves an imprint on the GW through its angular momentum exchange with the binary, the mass increase of the binary members due to accretion, and its gravity. We compute the disk-modified GWs both in an analytical Newtonian approximation and in a numerical effective-one-body approach. We find that disk-induced migration provides the dominant perturbation to the inspiral, with weaker effects from the mass accretion onto the CO and hydrodynamic drag. Depending on whether a gap is present, the perturbation of the GW phase is between 10 and 1000 rad per year, detectable with the future Laser Interferometer Space Antenna at high significance. The perturbation is significant for disk models with an effective viscosity proportional to gas pressure but much less so if proportional to the total pressure. The Fourier transform of the disk-modified GW in the stationary phase approximation is sensitive to disk parameters with a frequency trend different from post-Newtonian vacuum corrections. Our results suggest that observations of extreme mass-ratio inspirals may place new sensitive constraints on the physics of accretion disks.

The finite-temperature effective potential customarily employed to describe the physics of cosmological phase transitions often relies on specific gauge choices, and is manifestly not gauge invariant at finite order in its perturbative expansion. As a result, quantities relevant for the calculation of the spectrum of stochastic gravity waves resulting from bubble collisions in first-order phase transitions are also not gauge invariant. We assess the quantitative impact of this gauge dependence on key quantities entering predictions for gravity waves from first-order cosmological phase transitions. We resort to a simple Abelian Higgs model, and discuss the case of $R_{\xi }$ gauges. By comparing with results obtained using a gauge-invariant Hamiltonian formalism, we show that the choice of gauge can have a dramatic effect on theoretical predictions for the normalization and shape of the expected gravity wave spectrum. We also analyze the impact of resumming higher-order contributions as needed to maintain the validity of the perturbative expansion, and show that doing so can suppress the amplitude of the spectrum by an order of magnitude or more. We comment on open issues and possible strategies for carrying out “daisy resummed” gauge-invariant computations in non-Abelian models for which a gauge-invariant Hamiltonian formalism is not presently available.

We present an assessment of the standard model expectations for the branching ratio of the isotopic spin and G-parity violating decay $\tau \to {\eta }^{\prime }\pi {\nu }_{\tau }$. This estimate is based on a vector and scalar meson dominance parametrization of the relevant form factors, that explicitly accounts for ${\pi }^0-\eta -{\eta }^{\prime }$ mixing. The numerical results obtained in this framework indicate a branching ratio 1 order of magnitude (or more) below the current experimental limit and suggest the possibility of evidencing some novel interaction in high statistics studies of this decay.

We investigate the prospects for the discovery of massive color-octet vector bosons at the CERN Large Hadron Collider with $\sqrt{s}=14\mathrm{TeV}$. A phenomenological Lagrangian is adopted to evaluate the cross section of a pair of colored vector bosons (colorons, $\tilde{\rho }$) decaying into four colored scalar resonances (hyper-pions, $\tilde{\pi }$), which then decay into eight gluons. We include the dominant physics background from the production of $8g$, $7g1q$, $6g2q$, and $5g3q$, and determine the masses of $\tilde{\pi }$ and $\tilde{\rho }$ where discovery is possible. For example, we find that a $5\sigma$ signal can be established for $M_{\tilde{\pi }}\lesssim 495\mathrm{GeV}$ ($M_{\tilde{\rho }}\lesssim 1650\mathrm{GeV}$). More generally we give the reach of this process for a selection of possible cuts and integrated luminosities.