Considering the cubic theory of gravity which has been constructed in R. C. Myers and B. Robinson, J. High Energy Phys. 08 (2010); 067R. C. Myers and A. Sinha, Phys. Rev. D 82, 046006 (2010); R. C. Myers and A. Sinha, J. High Energy Phys. 01 (2011) 125, we study the existence of Lifshitz and hyperscaling-violating Lifshitz solutions. We first extend the black hole solution of R. C. Myers and B. Robinson, J. High Energy Phys. 08 (2010); 067R. C. Myers and A. Sinha, Phys. Rev. D 82, 046006 (2010); R. C. Myers and A. Sinha, J. High Energy Phys. 01 (2011) 125 and find that such extended solutions are valid for any value of dynamical exponent $z$. Next, we examine the existence of the AdS black hole solution with nonzero hyperscaling-violating exponent $\theta$ and general dynamical exponent $z$. We find that the solutions do exist only for $\theta =0$, 2 in four dimensions and $\theta =0$, 3 in five dimensions. In particular, when $\theta =2(3)$ in four (five) dimensions, we have Lifshitz and Schwarzschild–AdS black hole solutions for $z=\{0,1\}$.

On lattice gauge field configurations with $2+1$ dynamical quark flavors, we investigate the momentum space quark and gluon propagators in the combined maximally Abelian plus $U(1{)}_3\times U(1{)}_8$ Landau gauge. We extract the gluon fields from the lattice link variables and study the diagonal and off-diagonal gluon propagators. We find that the infrared region of the transverse diagonal gluon propagator is strongly enhanced compared to the off-diagonal propagator. The Dirac operator from the Asqtad action is inverted on the diagonal and off-diagonal gluon backgrounds separately. In agreement with the hypothesis of infrared Abelian dominance, we find that the off-diagonal gluon background hardly gives rise to any nontrivial quark dynamics while the quark propagator from the diagonal gluon background closely resembles its Landau gauge counterpart.

Predictions are provided for double differential cross sections and forward-backward ratios of $D^0$ production in $p\mathrm{Pb}$ (forward) and $\mathrm{Pb}p$ (backward) collisions at 5.02 TeV. The effect of nuclear corrections on the ratio of differential cross sections ratios is estimated to be $\simeq (10–30)\%$ in the kinematically accessible region of LHCb, and interestingly this ratio is approximately flat with respect to $p_T(D^0)$ due to a compensation of shadowing and antishadowing effects arising from the input nuclear parton distribution functions. In comparison to $J/\psi (\to {\mu }^{-}{\mu }^{+})$ measurements which have already been performed with the available data, the cross section for $D^0(\to K^{-}{\pi }^{+})$ production is expected to be 2 orders of magnitude higher.

We perform a systematic study of the generic Gatto-Sartori-Tonin relation, ${\tan }^2{\theta }_{ij}=m_i/m_j$. This study of fermion mixing phenomena leads us to the necessary conditions that are needed in order to obtain it without any approximation. We begin by considering two Dirac fermion families. By means of the hierarchy in the masses, it is found that a sufficient and necessary condition is to have a normal matrix with $m_{11}=0$. This matrix can be decomposed into two different linearly independent contributions. The origin for two independent contributions can be explained naturally by what we shall call the flavor-blind principle. This principle states that Yukawa couplings shall be either flavor blind or decomposed into several sets obeying distinct permutation symmetries. In general, it is shown that the symmetry properties of the introduced set of Yukawa matrices follow for $n$ fermion families the unique sequential breaking $S_{nL}\otimes S_{nR}\to S_{(n-1)L}\otimes S_{(n-1)R}\to \cdots \to S_{2L}\otimes S_{2R}\to S_{2A}$. The particular case of three fermion families explains why the four mass ratios parametrization that we recently proposed can be used even in the case of no hierarchical masses.

We discuss the prospects to probe the light-quark Yukawa couplings to the Higgs boson. The Higgs coupling to the charm quark can be probed both via inclusive and exclusive approaches. On the inclusive frontier, we use our recently proposed method together with published experimental studies for the sensitivity of the Higgs coupling to bottom quarks to find that the high-luminosity LHC can be sensitive to modifications of the charm Yukawa of the order of a few times its standard model (SM) value. We also present a preliminary study of this mode for a 100 TeV hadronic machine (with similar luminosity) and find that the bound can be further improved, possibly within the reach of the expected signal in the SM. On the exclusive frontier, we use the recent ATLAS search for charmonia and photon final state. This study yields the first measurement of the background relevant to these modes. Using this background measurement we project that at the high-luminosity LHC, unless the analysis strategy is changed, the sensitivity of the exclusive final state to the charm Yukawa to the charm Yukawa will be rather poor, of the order of 50 times the SM coupling. We then use a Monte-Carlo study to rescale the above backgrounds to the $h\to \varphi \gamma$ case and obtain a much weaker sensitivity to the strange Yukawa, of order of 3000 times the SM value. We briefly speculate what would be required to improve the prospects of the exclusive modes.

Warped models with the Higgs confined to the weak brane and the gauge and matter fields accessing the ${\mathrm{AdS}}_5$ bulk provide a viable setting to address the gauge hierarchy problem. Brane kinetic terms for the bulk fields are known to ease some of the tensions of these models with precision electroweak observables and flavor constraints. We study the loop-driven Higgs coupling to the gluons that are relevant to the Higgs program at the LHC, in this scenario. We demonstrate a partial cancellation in the contribution of the fermionic Kaluza-Klein (KK) towers within such framework relatively independent of the 5D parameters. The entire dependence of this coupling on the new physics arises from the mixing between the Standard Model states and the KK excitations. We find that the present precision in measurement of these couplings can lead to a constraint on the KK scale up to 1.2 TeV at 95% confidence level.

We give a gauge-independent definition of magnetic monopoles in the $SU(N)$ Yang-Mills theory through the Wilson loop operator. For this purpose, we give an explicit proof of the Diakonov-Petrov version of the non-Abelian Stokes theorem for the Wilson loop operator in an arbitrary representation of the $SU(N)$ gauge group to derive a new form for the non-Abelian Stokes theorem. The new form is used to extract the magnetic-monopole contribution to the Wilson loop operator in a gauge-invariant way, which enables us to discuss confinement of quarks in any representation from the viewpoint of the dual superconductor vacuum.

We investigate nonlocal field theories, a subject that has attracted some renewed interest in connection with nonlocal gravity models. We study, in particular, scalar theories of interacting delocalized fields, the delocalization being specified by nonlocal integral kernels. We distinguish between strictly nonlocal and quasilocal (compact support) kernels and impose conditions on them to insure UV finiteness and unitarity of amplitudes. We study the classical initial value problem for the partial integro-differential equations of motion in detail. We give rigorous proofs of the existence but accompanying loss of uniqueness of solutions due to the presence of future, as well as past, “delays,” a manifestation of acausality. In the quantum theory we derive a generalization of the Bogoliubov causality condition equation for amplitudes, which explicitly exhibits the corrections due to nonlocality. One finds that, remarkably, for quasilocal kernels all acausal effects are confined within the compact support regions. We briefly discuss the extension to other types of fields and prospects of such theories.

The rotation of the cosmic objects is a universal phenomenon and its origin is still an open question. Here a model for the origin of rotation is presented. After an investigation of the phase transition of a scalar field in de Sitter and Gödel backgrounds, the motion of a test particle during the phase transitions is studied. Then using computer simulation for a congruence of particles, we show that although the local induced rotation is nonzero, the global rotation is below the observational limit.

We present results on the nucleon scalar, axial, and tensor charges as well as on the momentum fraction, and the helicity and transversity moments. The pion momentum fraction is also presented. The computation of these key observables is carried out using lattice QCD simulations at a physical value of the pion mass. The evaluation is based on gauge configurations generated with two degenerate sea quarks of twisted mass fermions with a clover term. We investigate excited states contributions with the nucleon quantum numbers by analyzing three sink-source time separations. We find that, for the scalar charge, excited states contribute significantly and to a less degree to the nucleon momentum fraction and helicity moment. Our result for the nucleon axial charge agrees with the experimental value. Furthermore, we predict a value of 1.027(62) in the $\overline{\mathrm{MS}}$ scheme at 2 GeV for the isovector nucleon tensor charge directly at the physical point. The pion momentum fraction is found to be $⟨x{⟩}_{u-d}^{{\pi }^{\pm }}=0.214(15){(}_{-9}^{+12})$ in the $\overline{\mathrm{MS}}$ at 2 GeV.

In a $d$-dimensional conformal field theory, it has been known that a relevant deformation operator with the conformal dimension, $\mathrm{\Delta }=\frac{d+2}{2}$, generates a logarithmic correction to the entanglement entropy. In the large ’t Hooft coupling limit, we can investigate such a logarithmic correction holographically by deforming an AdS space with a massive scalar field dual to the operator with $\mathrm{\Delta }=\frac{d+2}{2}$. There are two sources generating the logarithmic correction. One is the metric deformation and the other is the minimal surface deformation. In this work, we investigate the change of the entanglement entropy caused by the minimal surface deformation and find that the second order minimal surface deformation leads to an additional logarithmic correction.

We give a covariant construction of Lagrangians for spinor fields in generic Newton-Cartan backgrounds. A nonrelativistic Dirac or Lévy-Leblond operator and the associated fields are obtained from relativistic analogues by a limiting procedure. The relativistic symmetries induce the complete set of nonrelativistic symmetries, including Milne boosts and local Galilean transformations. The resulting Lévy-Leblond operator includes nonminimal couplings to the Newton-Cartan structure as well as to the gauge field, and with these couplings it transforms covariantly. Phenomenologically, this fixes the gyromagnetic ratio to $g=1$. Three-dimensional spacetimes are an exception: generic $g$ is possible but results in modified Milne transformations, which—upon gauge fixing—reproduces the anomalous diffeomorphisms found in earlier approaches.

The anomalous dimensions of operators in the purely gluonic $\mathrm{SU}(2,1|2)$ sector of any planar conformal $\mathcal{N}=2$ theory can be read off from the $\mathcal{N}=4$ SYM results by replacing the $\mathcal{N}=4$ coupling constant with an interpolating function of the $\mathcal{N}=2$ coupling constants [1], which we refer to as the effective coupling. For a large class of $\mathcal{N}=2$ theories, we compute the weak-coupling expansion of these functions as well as the leading strong-coupling term by employing supersymmetric localization. Via Feynman diagrams, we interpret our results as the relative (between $\mathcal{N}=2$ and $\mathcal{N}=4$) finite renormalization of the coupling constant. Using the $\mathrm{AdS}/\mathrm{CFT}$ dictionary, we identify the effective couplings with the effective string tensions of the corresponding gravity dual theories. Thus, any observable in the $\mathrm{SU}(2,1|2)$ sector can be obtained from its $\mathcal{N}=4$ counterpart by replacing the $\mathcal{N}=4$ coupling constant with the universal, for a given theory, effective coupling.

We introduce a new kind of space-filling brane, which we term “G-brane” because its action is a descendant of the gravitational action. The G-brane may be thought of as the remanent of the gravitational field when the propagating gravitons are removed. The G-brane is different from the Dirac or Nambu space-filling branes. Its properties in any spacetime dimension $D$ are exhibited. When the spacetime dimension $D$ is greater than or equal to three, the G-brane does not possess propagating degrees of freedom, just as the Dirac or Nambu branes. For $D=3$ the G-brane yields a reformulation of gravitation theory in which the Hamiltonian constraints can be solved explicitly, while keeping the spacetime structure manifest. For $D=2$ the G-brane provides a realization of the conformal algebra, i.e. a conformal field theory, in terms of two scalar fields and their conjugates, which possesses a classical central charge. In the G-brane reformulation of ($2+1$) gravity, the boundary degrees of freedom of the gravitational field in asymptotically anti–de Sitter space appear as “matter” coupled to the ($1+1$) G-brane on the boundary.

The connection between black hole thermodynamics and chemistry is extended to the lower-dimensional regime by considering the rotating and charged Bañados, Teitelboim, and Zanelli (BTZ) metric in the ($2+1$)-dimensional and ($1+1$)-dimensional limits of Einstein gravity. The Smarr relation is naturally upheld in both BTZ cases, where those with $Q\ne 0$ violate the reverse isoperimetric inequality and are thus superentropic. The inequality can be maintained, however, with the addition of a new thermodynamic work term associated with the mass renormalization scale. The $D\to 0$ limit of a generic $D+2$-dimensional Einstein gravity theory is also considered to derive the Smarr and Komar relations, although the opposite sign definitions of the cosmological constant and thermodynamic pressure from the $D>2$ cases must be adopted in order to satisfy the relation. The requirement of positive entropy implies an upper bound on the mass of a $(1+1)\text{−}D$ black hole. Promoting an associated constant of integration to a thermodynamic variable allows one to define a “rotation” in one spatial dimension. Neither the $D=3$ nor the $D\to 2$ black holes exhibit any interesting phase behavior.

We study quantum corrections to the classical Bianchi I and Bianchi IX universes. The modified dynamics is well motivated from the asymptotic safety program where the short-distance behavior of gravity is governed by a nontrivial renormalization group fixed point. The correction terms induce a phase transition in the dynamics of the model, changing the classical, chaotic Kasner oscillations into a uniform approach to a point singularity. The resulting implications for the microscopic structure of spacetime are discussed.

A new Lagrangian framework has recently been proposed to describe interactions between relativistic perfect fluids and scalar fields. In this paper we investigate the Einstein static universe in this new class of theories, which have been named scalar-fluid theories. The stability of the static solutions to both homogeneous and inhomogeneous perturbations is analyzed deriving the relevant cosmological perturbation equations at the linear order. We can find several configurations corresponding to an Einstein static universes which are stable against inhomogeneous perturbations, but unstable against homogeneous perturbations. This shows the possible applications of scalar-fluid theories to the inflationary emergent universe scenario.

In the Kerr-Newman spacetime the Teukolsky master equation, governing the fundamental test fields, is of great importance. We derive an analogous master equation for the nonrotating $C$-metric which encompasses a massless Klein-Gordon field, neutrino field, Maxwell field, Rarita-Schwinger field and gravitational perturbations. This equation is shown to be separable in terms of “accelerated spin-weighted spherical harmonics.” It is shown that, contrary to ordinary spin-weighted spherical harmonics, the “accelerated” ones are different for different spins. In some cases, the equations for eigenfunctions and eigenvalues are explicitly solved.

Measurements of the cross-correlation between the extragalactic gamma-ray background (EGB) and large-scale structure provide a novel probe of dark matter on extragalactic scales. We focus on luminous red galaxies (LRGs) as optimal targets to search for the signal of dark matter annihilation. We measure the cross-correlation function of the EGB taken from the Fermi Large Area Telescope with the LRGs from the Sloan Digital Sky Survey. Statistical errors are calculated using a large set of realistic mock LRG catalogs. The amplitude of the measured cross-correlation is consistent with null detection. Based on an accurate theoretical model of the distribution of dark matter associated with LRGs, we exclude dark matter annihilation cross-sections over $⟨\sigma v⟩=3\times {10}^{-25}–10^{-26}{\mathrm{cm}}^3{\mathrm{s}}^{-1}$ for a 10 GeV dark matter. We further investigate systematic effects due to uncertainties in the Galactic gamma-ray foreground emission, which we find to be an order of magnitude smaller than the current statistical uncertainty. We also estimate the contamination from astrophysical sources in the LRGs by using known scaling relations between gamma-ray luminosity and star-formation rate, finding them to be negligibly small. Based on these results, we suggest that LRGs remain ideal targets for probing dark matter annihilation with future EGB measurement and galaxy surveys. Increasing the number of LRGs in upcoming galaxy surveys such as LSST would lead to big improvements of factors of several in sensitivity.

We present our study on cosmic opacity, which relates to changes in photon number as photons travel from the source to the observer. Cosmic opacity may be caused by absorption or scattering due to matter in the Universe, or by extragalactic magnetic fields that can turn photons into unobserved particles (e.g., light axions, chameleons, gravitons, Kaluza-Klein modes), and it is crucial to correctly interpret astronomical photometric measurements like type Ia supernovae observations. On the other hand, the expansion rate at different epochs, i.e., the observational Hubble parameter data $H(z)$, are obtained from differential ageing of passively evolving galaxies or from baryon acoustic oscillations and thus are not affected by cosmic opacity. In this work, we first construct opacity-free luminosity distances from $H(z)$ determinations, taking into consideration correlations between different redshifts for our error analysis. Moreover, we let the light-curve fitting parameters, accounting for distance estimation in type Ia supernovae observations, free to ensure that our analysis is authentically cosmological-model independent and gives a robust result. Any nonzero residuals between these two kinds of luminosity distances can be deemed as an indication of the existence of cosmic opacity. While a transparent Universe is currently consistent with the data, our results show that strong constraints on opacity (and consequently on physical mechanisms that could cause it) can be obtained in a cosmological-model-independent fashion.