15844300
FLUX COMPACTIFICATIONS AND SUPERSYMMETRY BREAKING IN 6D GAUGED SUPERGRAVITY
We review on a recent construction of the on-shell supersymmetric brane action for the codimension-two branes with nonzero tension in the flux compactification of a 6D chiral gauged supergravity. On dimensionally reducing on 4D gauged supergravity for a new supersymmetric unwarped background with conical branes, we consider the modulus stabilization for determining the soft masses of the scalars localized on the branes and show that the bulk U(1)R provides a new mechanism for mediating the SUSY breaking.
119351828
Self-tuning solution of the cosmological constant problem with antisymmetric tensor field
We obtain the self-tuning solution of the cosmological constant problem in the Randall-Sundrum model with introducing a three-index antisymmetric tensor field of a specific form in the Lagrangian. We also consider the dual description of the self-tuning solution.
119217517
U(1)R mediation from the flux compactification in six dimensions
We consider a supersymmetric completion of codimension‐two branes with nonzero tension in a 6D gauged supergravity. As a consequence, we obtain the football solution with 4D Minkowski space as a new supersymmetric background that preserves 4D N = 1 SUSY. In the presence of brane multiplets, we derive the 4D effective supergravity action for the football background and show that the remaining modulus can be stabilized by a bulk non‐perturbative correction with brane uplifting potentials at a zero vacuum energy. We find that the U(1)R mediation can be a dominant source of SUSY breaking for a brane scalar with nonzero R charge.
119248157
Vector Higgs-portal dark matter and the invisible Higgs
The Higgs sector of the Standard Model offers a unique probe of the hidden sector. In this work, we explore the possibility of renormalizable Higgs couplings to the hidden sector vector fields which can constitute dark matter (DM). Abelian gauge sectors with minimal field content, necessary to render the gauge fields massive, have a natural Z2 parity. This symmetry ensures stability of the vector fields making them viable dark matter candidates, while evading the usual electroweak
14096456
Wave function of the radion in the brane background with a massless scalar field and a self-tuning problem
We consider flat solutions in a brane world model with a massless scalar field appearing in 5D ${H}_{\mathrm{MNPQ}}^{2}.$ Since those solutions have naked bulk singularities or are such that the 4D Planck mass is divergent, we should have a compact extra dimension, the size of which is then fixed by brane tension(s) and the bulk cosmological constant. By inspecting scalar perturbations around the flat solutions, we find that there is no zero mode for the radion and radion modes have only positive masses. This result confirms the fact that the radius of the extra dimension cannot be adjusted independently of the parameters of the model, and thus that the model considered does not solve the problems encountered in other approaches to the self-tuning of the cosmological constant.
14725085
Various modified solutions of the Randall–Sundrum model with the Gauss–Bonnet interaction
Abstract The Gauss–Bonnet interaction is the only consistent quadratic interaction below the Planck scale in the Randall–Sundrum compactification. We study various static and inflationary solutions including this Gauss–Bonnet interaction.
73621594
Long-Range Lepton Flavor Interactions and Neutrino Oscillations
Recent results from the MINOS accelerator neutrino experiment suggest a possible difference between {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance oscillation parameters, which one may ascribe to a new long distance potential acting on neutrinos. As a specific example, we consider a model with gauged B - L{sub e} - 2L{sub {tau}} number which contains an extremely light new vector boson, m{sub Z}, < 10{sup -18} eV and extraordinarily weak coupling {alpha}{prime} {approx}< 10{sup -52}. In that case, differences between {nu}{sub {mu}} {yields} {nu}{sub {tau}} and {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub {tau}} oscillations can result from a long-range potential due to neutrons in the Earth and the Sun that distinguishes {nu}{sub {mu}} and {nu}{sub {tau}} on Earth, with a potential difference of {approx} 6 x 10{sup -14} eV, and changes sign for anti-neutrinos. We show that existing solar, reactor, accelerator, and atmospheric neutrino oscillation constraints can be largely accommodated for values of parameters that help explain the possible MINOS anomaly by this new physics, although there is some tension with atmospheric constraints. A long-range interaction, consistent with current bounds, could have very pronounced effects on atmospheric neutrino disappearance in the 20-50 GeV range that will be studied with themore » IceCube DeepCore array, currently in operation, and can have a significant effect on future high-precision long-baseline oscillation experiments which aim for {+-}1% sensitivity, in {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance, separately. Together, these experiments can extend the reach for new long-distance effects well beyond current bounds and test their relevance to the aforementioned MINOS anomaly. We also point out that long-range potentials originating from the Sun could lead to annual modulations of neutrino data at the percent level, due to the variation of the Earth-Sun distance. A similar phenomenology is shown to apply to other potential new gauge symmetries such as L-3L{sub {tau}} and B-3L{sub {tau}}.« less
118552297
Muon g − 2 anomaly and dark leptonic gauge boson
One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.
119235421
Gauged B-x(i)L origin of R parity and its implications
Abstract Gauged B − L is a popular candidate for the origin of the conservation of R parity, i.e. R = ( − ) 3 B + L + 2 j , in supersymmetry, but it fails to forbid the effective dimension-five terms arising from the superfield combinations Q Q Q L , u c u c d c e c , and u c d c d c N c , which allow the proton to decay. Changing it to B − x i L , where x e + x μ + x τ = 3 (with x i ≠ 1 ) for the three families, would forbid these terms while still serving as a gauge origin of R parity. We show how this is achieved in two minimal models with realistic neutrino mass matrices, and discuss their phenomenological implications.
14087471
Generalized lepton number and dark left-right gauge model
In a left-right gauge model of particle interactions, the left-handed fermion doublet $(\ensuremath{\nu},e{)}_{L}$ is connected to its right-handed counterpart $(n,e{)}_{R}$ through a scalar bidoublet so that ${e}_{L}$ pairs with ${e}_{R}$, and ${\ensuremath{\nu}}_{L}$ with ${n}_{R}$ to form mass terms. Suppose the latter link is severed without affecting the former, then ${n}_{R}$ is not the mass partner of ${\ensuremath{\nu}}_{L}$, and as we show in this paper, becomes a candidate for dark matter which is relevant for the recent PAMELA and ATIC observations. We accomplish this in a specific nonsupersymmetric model, where a generalized lepton number can be defined, so that ${n}_{R}$ and ${W}_{R}^{\ifmmode\pm\else\textpm\fi{}}$ are odd under $R\ensuremath{\equiv}(\ensuremath{-}1{)}^{3B+L+2j}$. Fermionic leptoquarks are also predicted.
59376303
Signs of Analyticity in Single-Field Inflation
The analyticity of response functions and scattering amplitudes implies powerful relations between low-energy observables and the underlying short-distance dynamics. These “IR/UV” relations are rooted in basic physical principles, such as causality and unitarity. In this paper, we seek similar connections in inflation, relating cosmological observations to the physics responsible for the accelerated expansion. We assume that the inflationary theory is Lorentz invariant at short distances, but allow for nonrelativistic interactions and a nontrivial speed of propagation at low energies. Focusing on forward scattering, we derive a “sum rule” which equates a combination of low-energy parameters to an integral which is sensitive to the high-energy behavior of the theory. While for relativistic amplitudes unitarity is sufficient to prove positivity of the sum rule, this is not guaranteed in the nonrelativistic case. We discuss the conditions under which positivity still applies, and show that they are satisfied by all known UV completions of single-field inflation. In that case, we obtain a consistency condition for primordial non-Gaussianity, which constrains the size and the sign of the equilateral four-point function in terms of the amplitude of the three-point function. The resulting bound rules out about half of the parameter space that is still allowed by current observations. Finding a violation of our consistency condition would point toward less conventional theories of inflation, or violations of basic physical principles.