We describe how the kinematic consistency relations satisfied by density correlations of the large-scale structures of the Universe can be derived within the usual Newtonian framework. These relations express a kinematic effect and show how the $(\ell +n)$-density correlation factors in terms of the $n$-point correlation and $\ell$ linear power spectrum factors, in the limit where the $\ell$ soft wave numbers become linear and much smaller than the $n$ other wave numbers. We describe how these relations extend to multifluid cases. In the standard cosmology, these consistency relations derive from the equivalence principle. A detection of their violation would indicate non-Gaussian initial conditions, non-negligible decaying modes, or a modification of gravity that does not converge to general relativity on large scales.

Using the chirally invariant overlap Dirac operator, we remove its lowest-lying quasizero modes from the valence quark propagators and study evolution of isovector mesons with $J=1$. At the truncation level, about 50 MeV $SU(2{)}_L\times SU(2{)}_R$ and $U(1{)}_A$ symmetries get restored. However, we observe a degeneracy not only within the chiral and $U(1{)}_A$ multiplets, but also a degeneracy of all possible chiral multiplets, i.e., the observed quantum levels have a symmetry larger than $U(2{)}_L\times U(2{)}_R$ and their energy does not depend on the spin orientation of quarks and their parities. We offer a possible interpretation of these energy levels as the quantum levels of the dynamical QCD string. The structure of the radial $J=1$ spectrum is compatible with $E=(n_r+1)\hslash \omega$ with $\hslash \omega =900\pm 70\mathrm{MeV}$.

We explore the Large Hadron Collider (LHC) phenomenology of dark matter (DM) pair production in association with a 125-GeV Higgs boson. This signature, dubbed “mono-Higgs,” appears as a single Higgs boson plus missing energy from DM particles escaping the detector. We perform an LHC background study for mono-Higgs signals at $\sqrt{s}=8$ and 14 TeV for four Higgs boson decay channels: $\gamma \gamma$, $b\overline{b}$, $Z{Z}^{*}\to 4\ell$, and $\ell \ell jj$. We estimate the LHC sensitivities to a variety of new physics scenarios within the frameworks of both effective operators and simplified models. For all of these scenarios, the $\gamma \gamma$ channel provides the best sensitivity, whereas the $b\overline{b}$ channel suffers from a large $t\overline{t}$ background. Mono-Higgs is unlike other mono-$X$ searches ($X=\text{jet}$, photon, etc.) since the Higgs boson is unlikely to be radiated as initial state radiation and therefore probes the underlying DM vertex directly.

We show that in the McLerran-Venugopalan model an axial asymmetrical valence quark distributions in the transverse plane of a transversely polarized proton can give rise to a spin-dependent odderon. Such polarized odderon is responsible for the transverse single spin asymmetries for jet production in the backward region of pp collisions and open charm production in the semi-inclusive deep inelastic scattering process.

Global fits for precision determinations of parton distributions, together with the highly correlated strong coupling ${\alpha }_s$, are presented up to next-to-next-to-leading order (NNLO) of QCD utilizing most world data (charm and jet production data are used where theoretically possible), except Tevatron gauge boson production data and LHC data which are left for genuine predictions. This is done within the “dynamical” (valence-like input at $Q_0^2=0.8{\mathrm{GeV}}^2$) and “standard” (input at $Q_0^2=2{\mathrm{GeV}}^2$) approach. The stability and reliability of the results are ensured by including nonperturbative higher-twist terms, nuclear corrections as well as target mass corrections, and by applying various ($Q^2$, $W^2$) cuts on available data. In addition, the $Q_0^2$ dependence of the results is studied in detail. Predictions are given, in particular for the LHC, for gauge- and Higgs-boson as well as for top-quark pair production. At NNLO the dynamical approach results in ${\alpha }_s(M_Z^2)=0.1136\pm 0.0004$, whereas the somewhat less constrained standard fit gives ${\alpha }_s(M_Z^2)=0.1162\pm 0.0006$.

We construct the full $p^6$ order chiral Lagrangians for the unitary group and special unitary groups, including $n_f$-, three- and two-flavor cases, all bilinear currents (scalar, pseudoscalar, vector, axial-vector, and tensor currents), and $\theta$ parameter. The number of independent operators are 1391, 1326, and 969 for each of the flavor unitary groups. From these results, we find one extra linear relation among the traditional $p^4$ order low-energy constants under the U(3) group, and some more linear relations with tensor sources for the $p^6$ order low-energy constants in the special unitary groups. We develop a scheme to obtain the relations for the dependent operators in terms of independent operators.

We consider the minimal seesaw model in which two gauge singlet right-handed neutrinos with opposite lepton numbers are added to the Standard Model. In this model, the smallness of the neutrino mass is explained by the tiny lepton number violating coupling between one of the singlets with the standard left-handed neutrinos. This allows one to have the right-handed neutrino mass at the TeV scale as well as appreciable mixing between the light and heavy states. This model is fully reconstructible in terms of the neutrino oscillation parameters apart from the overall coupling strengths. We show that the overall coupling strength $y_{\nu }$ for the Dirac-type coupling between the left-handed neutrino and one of the singlets can be restricted by consideration of the (meta)stability bounds on the electroweak vacuum. In this scenario the lepton flavor violating decays of charged leptons can be appreciable, which can put further constraint on $y_{\nu }$ for right-handed neutrinos at TeV scale. We discuss the combined constraints on $y_{\nu }$ for this scenario from the process $\mu \to e\gamma$ and from the consideration of vacuum (meta)stability constraints on the Higgs self-coupling. We also briefly discuss the implications for neutrinoless double beta decay and possible signatures of the model that can be expected at colliders.

Deflection angles of massive test particles moving along an unbound trajectory in the Schwarzschild metric are considered for the case of large deflection. We analytically consider the strong deflection limit, which is opposite to the commonly applied small deflection approximation and corresponds to the situation when a massive particle moves from infinity, makes several revolutions around a central object, and goes to infinity. For this purpose we rewrite an integral expression for the deflection angle as an explicit function of the parameters determining the trajectory and expand it. Remarkably, in the limiting case of strong deflection, we succeed in deriving for the first time the analytical formulas for deflection angles as explicit functions of parameters at infinity. In particular, we show that in this case the deflection angle can be calculated as an explicit function of the impact parameter and velocity at infinity beyond the usual assumption of small deflection.

Chameleon gravity is a scalar-tensor theory that includes a nonminimal coupling between the scalar field and the matter fields and yet mimics general relativity in the Solar System. The scalar degree of freedom is hidden in high-density environments because the effective mass of the chameleon scalar depends on the trace of the stress-energy tensor. In the early Universe, when the trace of the matter stress-energy tensor is nearly zero, the chameleon is very light, and Hubble friction prevents it from reaching the minimum of its effective potential. Whenever a particle species becomes nonrelativistic, however, the trace of the stress-energy tensor is temporarily nonzero, and the chameleon begins to roll. We show that these “kicks” to the chameleon field have catastrophic consequences for chameleon gravity. The velocity imparted to the chameleon by the kick is sufficiently large that the chameleon’s mass changes rapidly as it slides past its potential minimum. This nonadiabatic evolution shatters the chameleon field by generating extremely high-energy perturbations through quantum particle production. If the chameleon’s coupling to matter is slightly stronger than gravitational, the excited modes have trans-Planckian momenta. The production of modes with momenta exceeding $10^7\mathrm{GeV}$ can only be avoided for small couplings and finely tuned initial conditions. These quantum effects also significantly alter the background evolution of the chameleon field, and we develop new analytic and numerical techniques to treat quantum particle production in the regime of strong dissipation. This analysis demonstrates that chameleon gravity cannot be treated as a classical field theory at the time of big bang nucleosynthesis and casts doubt on chameleon gravity’s viability as an alternative to general relativity.

There exist well-known no-hair theorems forbidding the existence of hairy black hole solutions in general relativity coupled to a scalar conformal field theory in asymptotically flat space. Even in the presence of cosmological constant, where no-hair theorems can usually be circumvented and black holes with conformal scalar hair were shown to exist in $D\le 4$ dimensions, no-go results were reported for $D>4$. In this paper we prove that these obstructions can be evaded and we answer in the affirmative a question that remained open: Whether hairy black holes do exist in general relativity sourced by a conformally coupled scalar field in arbitrary dimensions. We find the analytic black hole solution in arbitrary dimension $D>4$, which exhibits a backreacting scalar hair that is regular everywhere outside and on the horizon. The metric asymptotes to (anti-)de Sitter spacetime at large distance and admits spherical horizon as well as horizon of a different topology. We also find analytic solutions when higher-curvature corrections $\mathcal{O}(R^n)$ of arbitrary order $n$ are included in the gravity action.

We consider the question of loop corrections (i.e. $1/N$) in the vector model/higher spin duality following the recent work of Giombi and Klebanov [J. High Energy Phys. 12, 068 (2013)]. The purpose of this paper is to gain further a more precise comparison between the two sides of the duality. For CFTs given by 3d $O(N)$ or $U(N)$ vector models we evaluate the leading and one-loop partition functions in a variety of geometries. Our calculations are performed in the scheme of collective field theory which was seen in earlier studies to represent a bulk description of Vasiliev higher spin theory. The calculations presented provide data for the comparison of small fluctuation determinants giving further evidence for the one-to-one bulk identification between the bilocal and the AdS pictures. They also offer insight into the identification of coupling constants $G$ and $1/N$ of the two descriptions for models based on $O(N)$ symmetry.

We introduce one pair of inert Higgs doublets $\{H_d,H_u\}$ and singlets $\{N^c,N\}$, and consider their couplings with the Higgs doublets of the minimal supersymmetric standard model (MSSM), $W\supset y_N{N}^c{h}_u{H}_d+y_N^{\prime }N{h}_d{H}_u$. We assign extra $\mathrm{U}(1{)}_{Z^{\prime }}$ gauge charges only to the extra vectorlike superfields, and so all the MSSM superfields remain neutral under the new $\mathrm{U}(1{)}_{Z^{\prime }}$. They can be an extension of the “$\lambda$ term,” $W\supset \lambda S{h}_u{h}_d$ in the next-to MSSM (NMSSM). Because of the $\mathrm{U}(1{)}_{Z^{\prime }}$, the maximally allowed low energy value of $y_N$ can be lifted up to 0.85, avoiding a Landau pole (LP) below the grand unification scale. Such colorless vectorlike superfields remarkably enhance the radiative MSSM Higgs mass particularly for large $\tan \beta$ through the $y_N$ term and the corresponding holomorphic soft term. As a result, the lower bound of $\lambda$ and the upper bound of $\tan \beta$ can be relaxed to disappear from the restricted parameter space of the original NMSSM, $0.6\lesssim \lambda \lesssim 0.7$ and $1<\tan \beta \lesssim 3$ for a light stop, ${\tilde{m}}_t\gtrsim 700\mathrm{GeV}$. Thus, the valid parameter space significantly expands up to $0\le \lambda \lesssim 0.75$, $0\le y_N\lesssim 0.88$, and $2\lesssim \tan \beta \lesssim 50$, evading the LP problem and also explaining the 126 GeV Higgs mass naturally.

Top taggers are established analysis tools used to reconstruct boosted hadronically decaying top quarks, for example, in searches for heavy resonances. We first present a dedicated study of signal efficiency versus background rejection, allowing for an improved choice of working points. Next, we determine to what degree our mass drop selection can be improved by systematically including angular correlations between subjets or $N$-subjettiness. Finally, we extend the reach of the top tagger to transverse momenta below the top mass. This momentum range will be crucial in searches for the associated production of a Higgs boson with top quarks.

A twisted ${\mathcal{C}}^{\star }$-algebra of the extended (noncommutative) Heisenberg-Weyl group has been constructed which takes into account the uncertainty principle for coordinates in the Planck-length regime. This general construction is then used to generate an appropriate Hilbert space and observables for the noncommutative theory which, when applied to the Bianchi I cosmology, leads to a new set of equations that describe the quantum evolution of the Universe. We find that this formulation matches theories based on a reticular Heisenberg-Weyl algebra in the bouncing and expanding regions of a collapsing Bianchi universe. There is, however, an additional effect introduced by the dynamics generated by the noncommutativity. This is an oscillation in the spectrum of the volume operator of the Universe, within the bouncing region of the commutative theories. We show that this effect is generic and produced by the noncommutative momentum exchange between the degrees of freedom in the cosmology. We give asymptotic and numerical solutions which show the above mentioned effects of the noncommutativity.

We study the dynamics of the oscillating gauged scalar field in a thermal bath. A Langevin-type equation of motion of the scalar field, which contains both dissipation and fluctuation terms, is derived by using the real-time finite-temperature effective action approach. The existence of the quantum fluctuation-dissipation relation between the nonlocal dissipation term and the Gaussian stochastic noise terms is verified. We find that the noise variables are anticorrelated at equal time. The dissipation rate for each mode is also studied, which turns out to depend on the wave number.

In this work we consider (1,1)-dimensional resonant Dirac fermionic states on tubelike topological defects. The defects are formed by rings in (2,1) dimensions, constructed with two scalar fields $\varphi$ and $\chi$, and embedded in the (3,1)-dimensional Minkowski spacetime. The tubelike defects are attained from a Lagrangian density explicitly dependent with the radial distance $r$ relative to the ring axis and the radius and thickness of its cross section are related to the energy density. For our purposes we analyze a general Yukawa-like coupling between the topological defect and the fermionic field $\eta F(\varphi ,\chi )\overline{\psi }\psi$. With a convenient decomposition of the fermionic fields in left and right components, we establish a coupled set of first-order differential equations for the amplitudes of the left and right components of the Dirac field. After decoupling and decomposing the amplitudes in polar coordinates, the radial modes satisfy Schrödinger-like equations whose eigenvalues are the masses of the fermionic states. With $F(\varphi ,\chi )=\varphi \chi$ the Schrödinger-like equations are numerically solved with appropriated boundary conditions. Several resonance peaks for both components are obtained, and the results are confronted with the qualitative analysis of the Schrödinger-like potentials.

We derive a conservative form of Boltzmann’s equation in general relativity, which is concisely written. Several explicit forms of this equation are written for black-hole spacetime with several coordinate conditions in real spacetime and momentum-space coordinates.

Inspired by quantum gravity proposals, we construct a deformed phase space which supports the UV and IR cutoffs. We show that the Liouville theorem is satisfied in the deformed phase space which allows us to formulate the thermodynamics of the early universe in the semiclassical regime. Applying the proposed method to the Snyder noncommutative space, we find a temperature dependent equation of state which opens a new window for the natural realization of inflation as a phase transition from the quantum gravity regime to the standard radiation dominated era. Also, we obtain finite energy and entropy densities for the Universe when at least the weak energy condition is satisfied. We show that there is a minimum size for the Universe which is proportional to the Planck length and consequently the big bang singularity is removed.

Associated to the unique 4-parametric subgroup of translations, normal to the Bondi–Metzner–Sachs group, there exists a generator of the temporal translation asymptotic symmetry. Such a descriptor of the motion along the conformal orbit near null infinity is propagated to finite regions. This allows us to observe the global energy conservation even in extreme situations near the critical behavior of the massless scalar field collapse in spherical symmetry.

Binary pulsars are ideal to test the foundations of general relativity, such as Lorentz symmetry, which requires that experiments produce the same results in all free-falling (i.e. inertial) frames. We here break this symmetry in the gravitational sector by specifying a preferred time direction, and thus a preferred frame, at each spacetime point. We then examine the consequences of this gravitational Lorentz symmetry breaking in the orbital evolution of binary pulsars, focusing on the dissipative effects. We find that Lorentz symmetry breaking modifies these effects, and thus the orbital dynamics, in two different ways. First, it generically causes the emission of dipolar radiation, which makes the orbital separation decrease faster than in general relativity. Second, the quadrupole component of the emission is also modified. The orbital evolution depends critically on the sensitivities of the stars, which measure how their binding energies depend on the motion relative to the preferred frame. We calculate the sensitivities numerically and compute the predicted orbital decay rate of binary pulsars in Lorentz-violating gravity. By testing these predictions against observations, we place very stringent constraints on gravitational Lorentz violation.