A complete 5-dimensional $\mathrm{SU}(5)$ unified theory is constructed which, on compactification the orbifold with two different ${Z}_{2}$'s ${(Z}_{2}$ and ${Z}_{2}^{\ensuremath{'}}),$ yields minimal supersymmetric standard model. The accomplishes gauge symmetry breaking, doublet-triplet splitting, a vanishing of proton decay from operators dimension 5. Until 4D supersymmetry broken, all 4 5 forced to vanish by an exact ${U(1)}_{R}$ symmetry. Quarks leptons their Yukawa interactions are...

We present composite models explaining the diphoton excess of mass around 750 GeV recently reported by LHC experiments.

We formulate a version of the information paradox in de Sitter spacetime and show that it is solved by emergence entanglement islands context De Sitter/de correspondence; particular, entropy subregion obeys time-dependent Page curve. Our construction works general dimensions keeps graviton massless. interpret resulting behavior using double holography. It suggests spatial distribution microscopic degrees freedom depends on descriptions, as case black hole. In static (distant) description...

Weak scale supersymmetry is often said to be fine-tuned, especially if the matter content minimal. This not true there a large $A$ term for top squarks. We present systematic study on fine-tuning in minimal supersymmetric theories and identify low-energy spectra that do lead severe fine-tuning. Characteristic features of these are: squarks, small squark masses, moderately $\mathrm{tan}\ensuremath{\beta}$, $\ensuremath{\mu}$ parameter. There are classes leading features, which discussed. In...

Motivated by the galactic positron excess seen PAMELA and ATIC/PPB-BETS, we propose that dark matter is a TeV-scale particle annihilates into pseudoscalar ``axion.'' The absence of an antiproton or gamma ray constrain axion mass branching ratios. In simplest realization, associated with Peccei-Quinn symmetry, in which case it has around 360--800 MeV decays muons. We present simple predictive supersymmetric model implementing this scenario, where both Higgsino obtain masses from same source...

A SU(3) \times SU(2) U(1) supersymmetric theory is constructed with a TeV sized extra dimension compactified on the orbifold S^1/(Z_2 Z_2'). The compactification breaks supersymmetry leaving set of zero modes which correspond precisely to states 1 Higgs doublet standard model. Supersymmetric Yukawa interactions are localized at fixed points. top quark hypermultiplet radiatively triggers electroweak symmetry breaking, yielding potential finite and exponentially insensitive physics above...

Models of cosmic inflation posit an early phase accelerated expansion the universe, driven by dynamics one or more scalar fields in curved spacetime. Though detailed assumptions about and couplings vary across models, makes specific, quantitative predictions for several observable quantities, such as flatness parameter (Ωk=1−Ω) spectral tilt primordial curvature perturbations (ns−1=dln⁡PR/dln⁡k), among others—predictions that match latest observations from Planck satellite to very good...

Motivated by the absence, so far, of any direct signal conventional low-energy supersymmetry, we explore consequences making lightest Higgs boson in supersymmetry relatively heavy, up to about 300 GeV, most straightforward way, i.e. via introduction a chiral singlet S with superpotential interaction doublets, λS H_1 H_2. The coupling λdominates over all other couplings and, maintain successful perturbative analysis ElectroWeak Precision Tests, is only restricted remain 10 TeV. general...

A bstract Multiple lines of evidence suggest that the Hilbert space an isolated de Sitter universe is one dimensional but can appear larger when probed by a gravitating observer. To test this idea, we compute von Neumann entropy field theory in two-dimensional which entangled thermal-like state with same on disjoint, asymptotically anti-de (AdS) black hole. Previously, it was shown replica trick for computing such systems requires inclusion non-perturbative effect quantum gravity — novel...

We construct supersymmetric models of SO(10) unification in which the gauge symmetry is broken by orbifold compactification. find that using boundary conditions to break down ${\mathrm{SU}(3)}_{C}\ensuremath{\bigotimes}{\mathrm{SU}(2)}_{L}\ensuremath{\bigotimes}{U(1)}_{Y}\ensuremath{\bigotimes}{U(1)}_{X}$ without leaving unwanted massless states requires at least two extra dimensions, motivating us work with 6D orbifolds. operations, each induces breaking either Georgi-Glashow, Pati-Salam,...

We systematically construct gauge-mediated supersymmetry- (SUSY-)breaking models with direct transmission of SUSY-breaking effects to the standard-model sector. obtain a natural model gravitino mass ${m}_{3/2}$ smaller than $1 \mathrm{keV}$ as required from standard cosmology. If all Yukawa coupling constants are order one, scale ${m}_{\mathrm{SUSY}}$ transmitted into sector is given by...

Gauge mediation of supersymmetry breaking is drastically simplified using generic superpotentials without U(1)_R symmetry by allowing metastable vacua.

If supersymmetry is broken directly to the Standard Model at energies not very far from unified scale, Higgs boson mass lies in range (128–141) GeV. The end points of this are tightly determined. Theories with dominantly a single supermultiplet predict upper edge, (141 ± 2) GeV, uncertainty dominated by experimental errors on top quark and QCD coupling. This edge prediction remarkably insensitive breaking scale supersymmetric threshold corrections so that, wide class theories, theoretical...

We study implications of the weak gravity conjecture in AdS/CFT correspondence. Unlike Minkowski spacetime, AdS spacetime has a physical length scale, so that must be generalized with an additional parameter. discuss possible generalizations and translate them into language dual CFTs, which take form inequalities involving dimension charge operator as well current energy-momentum tensor central charges. then test these against various CFTs to see if they are universally obeyed by all CFTs....

A coarse-grained description for the formation and evaporation of a black hole is given within framework unitary theory quantum gravity preserving locality, without dropping information that manifests as macroscopic properties state at late times. The resulting picture depends strongly on reference frame one chooses to describe process. In based in which point stays outside horizon sufficiently long time, becomes superposition holes different locations with spins, even if back formed from...

Higher dimensional grand unified theories, with gauge symmetry breaking by orbifold compactification, possess $\mathrm{SU}(5)$ at fixed points, and do not automatically lead to tree-level coupling unification. A new framework is introduced that guarantees precise unification---even the leading loop threshold corrections are predicted, although they model dependent. Precise agreement experimental result, ${\ensuremath{\alpha}}_{s}^{\mathrm{exp}}=0.117\ifmmode\pm\else\textpm\fi{}0.002,$ occurs...