A5044672040- Particle physics theoretical and experimental studies
- Black Holes and Theoretical Physics
- Cosmology and Gravitation Theories
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Hungarian Social, Economic and Educational Studies
- Russia and Soviet political economy
- Agricultural Economics and Policy
- High-Energy Particle Collisions Research
- Pulsars and Gravitational Waves Research
- Noncommutative and Quantum Gravity Theories
- Post-Communist Economic and Political Transition
- Particle Detector Development and Performance
- Agricultural economics and policies
- Neutrino Physics Research
- Computational Physics and Python Applications
- Agricultural Development and Policies
- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Quantum Electrodynamics and Casimir Effect
- Quantum Mechanics and Applications
- Relativity and Gravitational Theory
- International Science and Diplomacy
- Quantum Information and Cryptography
- Astrophysics and Cosmic Phenomena
Cornell University
2016-2025
Corvinus University of Budapest
2024
Physical Sciences (United States)
2012
University of California, Santa Barbara
2008-2009
World Bank
1995-2003
Los Alamos National Laboratory
2000-2002
University of California, Berkeley
1998-1999
Lawrence Berkeley National Laboratory
1997-1999
Massachusetts Institute of Technology
1994-1998
Berkeley College
1998
We analyze the cosmology of Randall-Sundrum model and that compact brane models in general presence a radius stabilization mechanism. find expansion our Universe is generically agreement with expected effective four dimensional description. The constraint (which responsible for appearance nonconventional cosmologies these models) must be imposed on matter densities two branes theory without stabilized consequence requiring static solution even absence stabilization. Such constraints...
We consider extra dimensional gauge theories on an interval. first review the derivation of consistent boundary conditions (BC's) from action principle. These BC's include choices that give rise to breaking symmetries. The could be chosen coincide with those commonly applied in orbifold theories, but there are many more possibilities. To investigate nature symmetry via we calculate elastic scattering amplitudes for longitudinal bosons. find using a set terms these explicitly grow energy...
We present a 5D gauge theory in warped space based on bulk $\mathrm{SU}(2{)}_{L}\ifmmode\times\else\texttimes\fi{}\mathrm{SU}(2{)}_{R}\ifmmode\times\else\texttimes\fi{}\mathrm{U}(1{)}_{B\ensuremath{-}L}$ group where the symmetry is broken by boundary conditions. The breaking pattern and mass spectrum resemble that standard model (SM). To leading order warp factor $\ensuremath{\rho}$ parameter coupling of $Z$ ($S$ parameter) are as SM, while corrections expected at level percent. From...
The dynamics of a stabilized radion in the Randall-Sundrum model with two branes is investigated, and effects on electroweak precision observables are evaluated. radius assumed to be using bulk scalar field as suggested by Goldberger Wise. First mass wave function determined including back reaction stabilization metric, giving typical order weak scale. This demonstrated perturbative computation function. A consequence background configuration for that after Kaluza-Klein states scalars couple...
For the closing article in this volume on supersymmetry, we consider alternative options to SUSY theories: present an overview of composite Higgs models light discovery boson. The small value physical mass suggests that quartic is likely loop generated; thus with tree-level quartics will generically be more tuned. We classify various (including bona fide Higgs, little holographic twin and dilatonic Higgs) based their predictions for potential, review basic ingredients each them, quantify...
We examine the theoretical motivations for long-lived particle (LLP) signals at LHC in a comprehensive survey of Standard Model (SM) extensions. LLPs are common prediction wide range theories that address unsolved fundamental mysteries such as naturalness, dark matter, baryogenesis and neutrino masses, represent natural generic possibility physics beyond SM (BSM). In most cases LLP lifetime can be treated free parameter from $\mu$m scale up to Big Bang Nucleosynthesis limit $\sim 10^7$m....
We calculate the tree-level expressions for electroweak precision observables in $\mathrm{SU}(5)/SO(5)$ littlest Higgs model. The source these corrections are exchange of heavy gauge bosons and a triplet vacuum expectation value (VEV). Weak isospin violating contributions present because there is no custodial $\mathrm{SU}(2)$ global symmetry. bulk weak arise from boson while smaller contribution comes VEV. A fit performed to experimental data we find that throughout parameter space symmetry...
We calculate the tree-level electroweak precision constraints on a wide class of little Higgs models including: variations Littlest SU(5)/SO(5), SU(6)/Sp(6), and SU(4)^4/SU(3)^4. By performing global fit to data we find that for generic regions parameter space bound symmetry breaking scale f is several TeV, where have kept normalization constant in different models. For example, ``minimal'' implementation SU(6)/Sp(6) bounded by f>3.0 TeV throughout most space, SU(4)^4/SU(3)^4 f^2 =...
We present a simple method for analyzing the impact of precision electroweak data above and below $Z$ peak on flavor-conserving, heavy new physics. find that experiments have probed about ten combinations new-physics effects, which to good approximation can be condensed into effective oblique parameters $\stackrel{^}{S}$, $\stackrel{^}{T}$, $\stackrel{^}{U}$, $V$, $X$, $W$, $Y$ (we prove positivity constraints $W,Y\ensuremath{\ge}0$) three quark couplings (including distinct parameter...
We present a simple model where photons propagating in extragalactic magnetic fields can oscillate into very light axions. The oscillations may convert some of the photons, departing distant supernova, axions, making supernova appear dimmer and hence more than it really is. Averaging over different configurations field we find that dimming saturates at about one-third from supernovae large redshifts. This results luminosity distance versus redshift curve almost indistinguishable produced by...
We consider fermions on an extra dimensional interval. find the boundary conditions at ends of interval that are consistent with variational principle, and explain which ones arise in various physical circumstances. apply these results to Higgsless models electroweak symmetry breaking, where is not broken by a scalar vacuum expectation value, but rather gauge fields. show it possible set for bulk would give realistic fermion mass spectrum without presence Higgs scalar, present some sample...
We consider the possibility that standard model Higgs fields may originate from extra components of higher dimensional gauge fields. Theories this type considered before have had problems accommodating fermion content and Yukawa couplings different coupling. Considering orbifolds based on Abelian discrete groups we are led to a 6 ${G}_{2}$ theory compactified ${T}^{2}{/Z}_{4}.$ This can naturally produce SM with right quantum numbers while predicting value weak mixing angle...
We consider various constraints on Higgsless models of electroweak symmetry breaking based a bulk SU(2)_L x SU(2)_R U(1)_{B-L} gauge group in warped space. First we show that the S parameter which is positive if fermions are localized Planck brane can be lowered (or made vanishing) by changing localization light fermions. If wave function almost flat their coupling to boson KK modes will close vanishing, and therefore contributions suppressed. At same time experimental bounds such Z' W'...
We consider the phenomenology of a resonance that couples to photons but not gluons, and estimate its production rate at LHC from photon-photon fusion in elastic pp scattering using effective photon narrow width approximations. The is sensitive only mass, spin, total resonance, branching fraction photons. Production cross sections 5-10 fb 13 TeV can be easily accommodated for 750 GeV with partial 15 GeV. This provides minimal explanation reported diphoton anomaly early Run II data.
We present an alternative approach to low-energy supersymmetry. Instead of imposing $R$-parity we apply the minimal flavor violation (MFV) hypothesis violating MSSM. In this framework, which call MFV SUSY, squarks can be light and proton long-lived without producing missing energy signals at LHC. Our differs from that Nikolidakis Smith in impose holomorphy on spurions. The resulting model is highly constrained emerges as accidental approximate symmetry Lagrangian. size small terms determined...
We consider the two-brane Randall-Sundrum (RS) model with bulk gauge fields. carefully match theory to a 4D low-energy effective Lagrangian. In addition four-fermion operators induced by KK exchange we find that large negative S and T parameters are in theory. This is tree-level effect consequence of shapes W Z wave functions bulk. Such effects generic extra dimensional theories where standard (SM) bosons have non-uniform along dimension. The corrections precision electroweak observables RS...