No Arabic abstract
The direct searches for Superymmetry at colliders can be complemented by direct searches for dark matter (DM) in underground experiments, if one assumes the Lightest Supersymmetric Particle (LSP) provides the dark matter of the universe. It will be shown that within the Constrained minimal Supersymmetric Model (CMSSM) the direct searches for DM are complementary to direct LHC searches for SUSY and Higgs particles using analytical formulae. A combined excluded region from LHC, WMAP and XENON100 will be provided, showing that within the CMSSM gluinos below 1 TeV and LSP masses below 160 GeV are excluded (m_{1/2} > 400 GeV) independent of the squark masses.
We systematically analyze the flavor color spin structure of the pentaquark $q^4bar{Q}$ system in a constituent quark model based on the chromomagnetic interaction in both the SU(3) flavor symmetric and SU(3) flavor broken case with and without charm quarks. We show that the originally proposed pentaquark state $bar{Q}s qqq$ by Gignoux et al and by Lipkin indeed belongs to the most stable pentaquark configuration, but that when charm quark mass correction based on recent experiments are taken into account, a doubly charmed antistrange pentaquark configuration ($udc c bar{s}$) is perhaps the only flavor exotic configuration that could be stable and realistically searched for at present through the $Lambda_c K^+ K^- pi^+$ final states. The proposed final state is just reconstructing $K^+$ instead of $pi^+$ in the measurement of $Xi^{++}_{cc} rightarrow Lambda_c K^- pi^+ pi^+$ reported by LHCb collaboration and hence measurable immediately.
We use the S-matrix bootstrap to carve out the space of unitary, crossing symmetric and supersymmetric graviton scattering amplitudes in ten dimensions. We focus on the leading Wilson coefficient $alpha$ controlling the leading correction to maximal supergravity. The negative region $alpha<0$ is excluded by a simple dual argument based on linearized unitarity (the desert). A whole semi-infinite region $alpha gtrsim 0.14$ is allowed by the primal bootstrap (the garden). A finite intermediate region is excluded by non-perturbative unitarity (the swamp). Remarkably, string theory seems to cover all (or at least almost all) the garden from very large positive $alpha$ -- at weak coupling -- to the swamp boundary -- at strong coupling.
Supersymmetry, a new symmetry that relates bosons and fermions in particle physics, still escapes observation. Search for supersymmetry is one of the main aims of the Large Hadron Collider. The other possible manifestation of supersymmetry is the Dark Matter in the Universe. The present lectures contain a brief introduction to supersymmetry in particle physics. The main notions of supersymmetry are introduced. The supersymmetric extension of the Standard Model -- the Minimal Supersymmetric Standard Model -- is considered in more detail. Phenomenological features of the Minimal Supersymmetric Standard Model as well as possible experimental signatures of supersymmetry at the Large Hadron Collider are described. The present limits on supersymmetric particles are presented and the allowed region of parameter space of the MSSM is shown.
This talk discusses various aspects of the structure of space-time presenting mechanisms leading to the explanation of the rigidity of the manifold and to the emergence of time, i.e. of the Lorentzian signature. The proposed ingredient is the analog, in four dimensions, of the deformation energy associated with the common threedimensional elasticity theory. The inclusion of this additional term in the Lagrangian of empty space-time accounts for gravity as an emergent feature from the microscopic structure of space-time. Once time has legitimately been introduced, a global positioning method based on local measurements of proper times between the arrivals of electromagnetic pulses from independent distant sources is presented. The method considers both pulsars as well as artificial emitters located on celestial bodies of the solar system as pulsating beacons to be used for navigation and positioning.
The energies of glue in the presence of a static quark-antiquark pair are calculated for separations r ranging from 0.1 fm to 4 fm and for various quark-antiquark orientations on the lattice. Our simulations use an improved gauge-field action on anisotropic space-time lattices. Discretization errors and finite volume effects are studied. We find that the spectrum does not exhibit the expected onset of the universal pi/r Goldstone excitations of the effective QCD string, even for r as large as 4 fm. Our results cast serious doubts on the validity of treating glue in terms of a fluctuating string for r below 2 fm. Retardation effects in the Upsilon system are also studied by comparing level splittings from the Born-Oppenheimer approximation with those directly obtained in simulations.