145,709 research outputs found
A Clifford Algebra Approach to Chiral Symmetry Breaking and Fermion Mass Hierarchies
We propose a Clifford algebra approach to chiral symmetry breaking and
fermion mass hierarchies in the context of composite Higgs bosons. Standard
model fermions are represented by algebraic spinors of six-dimensional binary
Clifford algebra, while ternary Clifford algebra-related flavor projection
operators control allowable flavor-mixing interactions. There are three
composite electroweak Higgs bosons resulted from top quark, tau neutrino, and
tau lepton condensations. Each of the three condensations gives rise to masses
of four different fermions. The fermion mass hierarchies within these three
groups are determined by four-fermion condensations, which break two global
chiral symmetries. The four-fermion condensations induce axion-like
pseudo-Nambu-Goldstone bosons and can be dark matter candidates. In addition to
the 125 GeV Higgs boson observed at the Large Hadron Collider, we anticipate
detection of tau neutrino composite Higgs boson via the charm quark decay
channel.Comment: 22 page
Symmetry analysis of the hadronic tensor for the semi-inclusive pseudoscalar meson leptoproduction from an unpolarized nucleon target
By examining the symmetry constraints on the semi-inclusive pseudoscalar
particle production in unpolarized inelastic lepton-hadron scattering, we
present a complete, exact Lorentz decomposition for the corresponding hadronic
tensor. As a result, we find that it contains five independent terms, instead
of the four as have been suggested before. The newly identified one is odd
under the naive time reversal transformation, and the corresponding structure
function is directly related to the single spin asymmetry in the semi-inclusive
pseudoscalar meson production by a polarized lepton beam off an unpolarized
target.Comment: This manuscript is of no use at its present form, so the author
withdrew it. Sorry
A State-Space Approach to Parametrization of Stabilizing Controllers for Nonlinear Systems
A state-space approach to Youla-parametrization of stabilizing controllers for linear and nonlinear systems is suggested. The stabilizing controllers (or a class of stabilizing controllers for nonlinear systems) are characterized as (linear/nonlinear) fractional transformations of stable parameters. The main idea behind this approach is to decompose the output feedback stabilization problem into state feedback and state estimation problems. The parametrized output feedback controllers have separation structures. A separation principle follows from the construction. This machinery allows the parametrization of stabilizing controllers to be conducted directly in state space without using coprime-factorization
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