18,267 research outputs found
On F-theory E_6 GUTs
We approach the Minimum Supersymmetric Standard Model (MSSM) from an E_6 GUT
by using the spectral cover construction and non-abelian gauge fluxes in
F-theory. We start with an E_6 singularity unfolded from an E_8 singularity and
obtain E_6 GUTs by using an SU(3) spectral cover. By turning on SU(2) X U(1)^2
gauge fluxes, we obtain a rank 5 model with the gauge group SU(3) X SU(2) X
U(1)^2. Based on the well-studied geometric backgrounds in the literature, we
demonstrate several models and discuss their phenomenology.Comment: 42 pages, 17 tables; typos corrected, clarifications added, and
references adde
Quench Dynamics of Topological Maximally-Entangled States
We investigate the quench dynamics of the one-particle entanglement spectra
(OPES) for systems with topologically nontrivial phases. By using dimerized
chains as an example, it is demonstrated that the evolution of OPES for the
quenched bi-partite systems is governed by an effective Hamiltonian which is
characterized by a pseudo spin in a time-dependent pseudo magnetic field
. The existence and evolution of the topological
maximally-entangled edge states are determined by the winding number of
in the -space. In particular, the maximally-entangled edge
states survive only if nontrivial Berry phases are induced by the winding of
. In the infinite time limit the equilibrium OPES can be
determined by an effective time-independent pseudo magnetic field
\vec{S}_{\mb{eff}}(k). Furthermore, when maximally-entangled edge states are
unstable, they are destroyed by quasiparticles within a characteristic
timescale in proportional to the system size.Comment: 5 pages, 3 figure
Estimating the Impacts of Climate Change on Mortality in OECD Countries
The major contribution of this study is to combines both climatic and macroeconomic factors simultaneously in the estimation of mortality using the capital city of 22 OECD countries from the period 1990 to 2008. The empirical results provide strong evidences that higher income and a lower unemployment rate could reduce mortality rates, while the increases in precipitation and temperature variation have significantly positive impacts on the mortality rates. The effects of changing average temperature on mortality rates in summer and winter are asymmetrical and also depend on the location. Combining the future climate change scenarios with the estimation outcomes show that mortality rates in OECD countries in 2100 will be increased by 3.77% to 5.89%.Climate change; mortality; panel data model
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