Journal of High Energy Physics

http://link.springer.com/journal/13130

List of Papers (Total 9,322)

One loop renormalization of the Littlest Higgs model

In Little Higgs models a collective symmetry prevents the Higgs from acquiring a quadratically divergent mass at one loop. This collective symmetry is broken by weakly gauged interactions. Terms, like Yukawa couplings, that display collective symmetry in the bare Lagrangian are generically renormalized into a sum of terms that do not respect the collective symmetry except possibly ...

Complete off-shell effects in top quark pair hadroproduction with leptonic decay at next-to-leading order

Results for next-to-leading order QCD corrections to the \( pp\left( {p\bar{p}} \right) \to t\bar{t} \to {W^{+} }{W^{-} }b\bar{b} \to {e^{+} }{\nu_e}{\mu^{-} }{\bar{\nu }_\mu }b\bar{b} + X \) processes with complete off-shell effects are presented for the first time. Double-, single-and non-resonant top contributions of the order \( \mathcal{O}\left( {\alpha_s^3{\alpha^4}} \right) ...

FCNC processes from D-brane instantons

Low string scale models might be tested at the LHC directly by their Regge resonances. For such models it is important to investigate the constraints of Standard Model precision measurements on the string scale. It is shown that highly suppressed FCNC processes like \( {K^0} - {\overline K^0} \) oscillations or leptonic decays of the D 0-meson provide non-negligible lower bounds on ...

A direct proof of AGT conjecture at β = 1

The AGT conjecture claims an equivalence of conformal blocks in 2d CFT and sums of Nekrasov functions (instantonic sums in 4d SUSY gauge theory). The conformal blocks can be presented as Dotsenko-Fateev β-ensembles, hence, the AGT conjecture implies the equality between Dotsenko-Fateev β-ensembles and the Nekrasov functions. In this paper, we prove it in a particular case of β = 1 ...

Aspects of the UV/IR correspondence: energy broadening and string fluctuations

We show that a source which radiates in the vacuum of the strongly coupled \( \mathcal{N} = 4 \) SYM theory produces an energy distribution which, in the supergravity approximation, has the same space-time pattern as the corresponding classical distribution: the radiation propagates at the speed of light without broadening. We illustrate this on the basis of several examples: a ...

CMB statistics in noncommutative inflation

Noncommutative geometry can provide effective description of physics at very short distances taking into account generic effects of quantum gravity. Inflation amplifies tiny quantum fluctuations in the early universe to macroscopic scales and may thus imprint high energy physics signatures in the cosmological perturbations that could be detected in the CMB. It is shown here that ...

Holography for Schrödinger backgrounds

We discuss holography for Schrödinger solutions of both topologically massive gravity in three dimensions and massive vector theories in (d + 1) dimensions. In both cases the dual field theory can be viewed as a d-dimensional conformal field theory (two dimensional in the case of TMG) deformed by certain operators that respect the Schrödinger symmetry. These operators are ...

Holographic dual of a boost-invariant plasma with chemical potential

We construct a gravity dual of a boost-invariant flow of an \( \mathcal{N} = 4 \) SU(N) supersymmetric Yang-Mills gauge theory plasma with chemical potential. We present both a first-order corrected late-time solution in Eddington-Finkelstein coordinates and a zeroth-order solution in parametric form in Fefferman-Graham coordinates. The resulting background takes the form of a ...

Perturbative analysis of the gradient flow in non-abelian gauge theories

The gradient flow in non-abelian gauge theories on \( {\mathbb{R}^4} \) is defined by a local diffusion equation that evolves the gauge field as a function of the flow time in a gauge-covariant manner. Similarly to the case of the Langevin equation, the correlation functions of the time-dependent field can be expanded in perturbation theory, the Feynman rules being those of a ...

Maximal electric dipole moments of nuclei with enhanced Schiff moments

The electric dipole moments (EDMs) of heavy nuclei, such as 199Hg, 225Ra and 211Rn, can be enhanced by the Schiff moments induced by the presence of nearby parity-doublet states. Working within the framework of the maximally CP-violating and minimally flavour-violating (MCPMFV) version of the MSSM, we discuss the maximal values that such EDMs might attain, given the existing ...

Effective action in a higher-spin background

We consider a free massless scalar field coupled to an infinite tower of background higher-spin gauge fields via minimal coupling to the traceless conserved currents. The set of Abelian gauge transformations is deformed to the non-Abelian group of unitary operators acting on the scalar field. The gauge invariant effective action is computed perturbatively in the external fields. ...

Closed flux tubes and their string description in D =3+1 SU(N) gauge theories

We calculate the energy spectrum of ac onfining flux tube that is closed around a spatial torus, as a function of its length l. We do so for various SU(N) gauge theories in 3+ 1 dimensions, and for various values of spin, parity and longitudinal momentum. We are able to present usefully accurate results for about 20 of the lightest such states, for a range of l that begins close to ...

Conformal field theories in anti-de Sitter space

In this paper we discuss the dynamics of conformal field theories on anti-de Sitter space, focussing on the special case of the \( \mathcal{N} = 4 \) supersymmetric Yang-Mills theory on AdS4. We argue that the choice of boundary conditions, in particular for the gauge field, has a large effect on the dynamics. For example, for weak coupling, one of two natural choices of boundary ...

3D gauged supergravity from wrapped M5-branes with AdS/CMT applications.

By identifying a bosonic consistent truncation from the \( \frac{1}{4} \)-BPS wrapped M5-brane geometry of Maldacena, Strominger and Witten in D = 11 supergravity and finding a supersymmetric extension, we recover an N = 2 D = 3 supergravity theory. Reductions of a large class of supersymmetric solutions corresponding to wrapped M2 and M5-branes lead to black strings and warped ...

Vacuum stability, string density of states and the Riemann zeta function

We study the distribution of graded degrees of freedom in classically stable oriented closed string vacua and use the Rankin-Selberg transform to link it to the finite one-loop vacuum energy. In particular, we find that the spectrum of physical excitations not only must enjoy asymptotic supersymmetry but actually, at very large mass, bosonic and fermionic states must follow a ...

Probing quantum geometry at LHC

We present an evidence, that the volumes of compactified spaces as well as the areas of black hole horizons must be quantized in Planck units. This quantization has phenomenological consequences, most dramatic being for micro black holes in the theories with TeV scale gravity that can be produced at LHC. We predict that black holes come in form of a discrete tower with well defined ...

Microscopic realization of the Kerr/CFT correspondence

Supersymmetric M/string compactifications to five dimensions contain BPS black string solutions with magnetic graviphoton charge P and near-horizon geometries which are quotients of AdS 3 × S 2. The holographic duals are typically known 2D CFTs with central charges c L = c R = 6P 3 for large P. These same 5D compactifications also contain non-BPS but extreme Kerr-Newman black hole ...

Twisting the mirror TBA

We study finite-size corrections to the magnon dispersion relation in three models which differ from string theory on AdS5 × S5 in their boundary conditions. Asymptotically, this is accomplished by twisting the transfer matrix in a way which manifestly preserves integrability. In model I all world-sheet fields are periodic, whereas model II represents a particular orbifold of AdS5 ...

Moduli and electromagnetic black brane holography

We investigate the thermodynamic and hydrodynamic properties of 4-dimensional gauge theories with finite electric charge density in the presence of a constant magnetic field. Their gravity duals are planar magnetically and electrically charged AdS black holes in theories that contain a gauge Chern-Simons term. We present a careful analysis of the near horizon geometry of these ...

Sum rules, plasma frequencies and Hall phenomenology in holographic plasmas

We study the AC optical and Hall conductivities of Dp/Dq-brane intersections in the probe approximation and use sum-rules to study various associated transport coefficients. We determine that the presence of massive fundamental matter, as compared to massless fundamental matter described holographically by a theory with no dimensional defects, reduces the plasma frequency. We ...

Domain wall holography for finite temperature scaling solutions

We investigate a class of near-extremal solutions of Einstein-Maxwell-scalar theory with electric charge and power law scaling, dual to charged IR phases of relativistic field theories at low temperature. These are exact solutions of theories with domain wall vacua; hence, we use nonconformal holography to relate the bulk and boundary theories. We numerically construct a global ...

An electron fixed target experiment to search for a new vector boson A′ decaying to e + e −

We describe an experiment to search for a new vector boson A′ with weak coupling α′ ≳ 6 × 10−8 α to electrons (α = e 2/4π) in the mass range 65 MeV m A′ A′ with the photon — one of the very few ways in which new forces can couple to the Standard Model — and have received considerable attention as an explanation of various dark matter related anomalies. A′ bosons are produced by ...

On D = 5 super Yang-Mills theory and (2, 0) theory

We discuss how D = 5 maximally supersymmetric Yang-Mills theory (MSYM) might be used to study or even to define the (2, 0) theory in six dimensions. It is known that the compactification of (2, 0) theory on a circle leads to D = 5 MSYM. A variety of arguments suggest that the relation can be reversed, and that all of the degrees of freedom of (2, 0) theory are already present in D ...

Searching for third-generation composite leptoquarks at the LHC

Fermion masses may arise via mixing of elementary fermions with composite fermions of a strong sector in scenarios of strongly-coupled electroweak symmetry breaking. The strong sector may contain leptoquark states with masses as light as several hundred GeV. In the present study we focus on the scalar modes of such leptoquarks since their bosonic couplings are determined completely ...