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Evading Weinberg's no-go theorem to construct mass dimension one fermions: Constructing darkness
Recent theoretical work reporting the construction of a new quantum field of
spin one half fermions with mass dimension one requires that Weinberg's no go
theorem must be evaded. Here we show how this comes about. The essence of the
argument is to first define a quantum field with due care being taken in fixing
the locality phases attached to each of the expansion coefficients. The second
ingredient is to systematically construct the adjoint/dual of the field. The
Feynman-Dyson propagator constructed from the vacuum expectation value of the
field and its adjoint then yields the mass dimensionality of the field. For a
quantum field constructed from a complete set of eigenspinors of the charge
conjugation operator, with locality phases judiciously chosen, the
Feynman-Dyson propagator has mass dimension one. The Lorentz symmetry is
preserved, locality anticommutators are satisfied, without violating fermionic
statistics as needed for the spin one half field.Comment: 8 pages, significantly extended published versio
Elko under spatial rotations
Under a rotation by an angle , both the right- and left- handed
Weyl spinors pick up a phase factor . The upper
sign holds for the positive helicity spinors, while the lower sign for the
negative helicity spinors. For radians this produces the
famous minus sign. However, the four-component spinors are built from a direct
sum of the indicated two-component spinors. The effect of the rotation by
radians on the eigenspinors of the parity - that is, the Dirac spinors
-- is the same as on Weyl spinors. It is because for these spinors the right-
and left- transforming components have the same helicity. And the rotation
induced phases, being same, factor out. But for the eigenspinors of the charge
conjugation operator, i.e. Elko, the left- and right- transforming components
have opposite helicities, and therefore they pick up opposite phases. As a
consequence the behaviour of the eigenspinors of the charge conjugation
operator (Elko) is more subtle: for a self conjugate spinor
becomes a linear combination of the self and antiself conjugate spinors with
dependent superposition coefficients - and yet the rotation
preserves the self/antiself conjugacy of these spinors! This apparently
paradoxical situation is fully resolved. This new effect, to the best of our
knowledge, has never been reported before. The purpose of this communication is
to present this result and to correct an interpretational error of a previous
version.Comment: 7 pages, Two new sections, and significantly new material. An error
in v1 and v2 correcte
Magnetic field creation by solar mass neutrino jets
Parity violation and its effects for neutrinos in astrophysical contexts have
been considered earlier in pioneering papers of Hawking and Vilenkin. But
because even the largest magnetic moments predicted by physics beyond the
Standard Model are some twelve orders of magnitude smaller than the Bohr
magneton, their implications for magnetic field generation and neutrino
oscillations are generally considered insignificant. Here we show that since in
astrophysical scenarios a huge number of neutrinos may be emitted, the
smallness of the magnetic moment, when coupled with parity violation, is
compensated by the sheer number of neutrinos. The merger of neutron stars would
leave behind a short pulse of electromagnetic synchrotron radiation even if the
neutrino jet in the merger points away from the neutrino detectors. We show
that the magnetic field can be as large as 10^6\,\mbox{Gauss} and comment on
the possibility of direct detection. Observation of such a pulse would lend
strong support for neutrino magnetic moments and resolve the missing neutrino
problem in neutron star mergers.Comment: 5 pages, version accepted for publication in Europhysics Letters
(EPL
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