3,520 research outputs found
Tachyon Dynamics - for Neutrinos?
Following earlier studies that provided a consistent theory of kinematics for
tachyons (faster-than-light particles) we here embark on a study of tachyon
dynamics, both in classical physics and in the quantum theory. Examining a
general scattering process we come to recognize that the labels given to "in"
and "out" states are not Lorentz invariant for tachyons; and this lets us find
a sensible interpretation of negative energy states. For statistical mechanics,
as well as for scattering problems, we study what should be the proper
expression for density of states for tachyons. We review the previous work on
quantization of a Dirac field for tachyons and go on to expand earlier
considerations of neutrinos as tachyons in the context of cosmology. We stumble
into the realization that tachyon neutrinos would contribute to gravitation
with the opposite sign compared to tachyon antineutrinos. This leads to the
gobsmacking prediction that the Cosmic Neutrino Background, if they are indeed
tachyons, might explain both phenomena of Dark Matter and Dark Energy. This
theoretical study also makes contact with the anticipated results from the
experiments KATRIN and PTOLEMY, which focus on beta decay and neutrino
absorption by Tritium.Comment: 27 pages; added Appendix B on Dark Matte
Revised Theory of Tachyons in General Relativity
A minus sign is inserted, for good reason, into the formula for the
Energy-Momentum Tensor for tachyons. This leads to remarkable theoretical
consequences and a plausible explanation for the phenomenon called Dark Energy
in the cosmos.Comment: 5 pages; minor changes in Section 2 and Section
A Conjecture about Conserved Symmetric Tensors
We consider T(x), a tensor of arbitrary rank that is symmetric in all of its
indices and conserved in the sense that the divergence on any one index
vanishes. Our conjecture is that all integral moments of this tensor will
vanish if the number of coordinates in that integral moment is less than the
rank of the tensor. This result is proved explicitly for a number of particular
cases, assuming adequate dimensionality of the Euclidean space of coordinates
(x); but a general proof is lacking. Along the way, we find some neat results
for certain large matrices generated by permutations
Toward a Quantum Theory of Tachyon Fields
We construct momentum space expansions for the wave functions that solve the
Klein-Gordon and Dirac equations for tachyons, recognizing that the mass shell
for such fields is very different from what we are used to for ordinary (slower
than light) particles. We find that we can postulate commutation or
anticommutation rules for the operators that lead to physically sensible
results: causality, for tachyon fields, means that there is no connection
between spacetime points separated by a timelike interval. Calculating the
conserved charge and 4-momentum for these fields allows us to interpret the
number operators for particles and antiparticles in a consistent manner; and we
see that helicity plays a critical role for the spinor field. Some questions
about Lorentz invariance are addressed and some remain unresolved; and we show
how to handle the group representation for tachyon spinors.Comment: 17 page
More Special Functions Trapped
We extend the technique of using the Trapezoidal Rule for efficient
evaluation of the Special Functions of Mathematical Physics given by integral
representations. This technique was recently used for Bessel functions, and
here we treat Incomplete Gamma functions and the general Confluent
Hypergeometric Function.Comment: 6 page
Experiment and Theory in Computations of the He Atom Ground State
Extensive variational computations are reported for the ground state energy
of the non-relativistic two-electron atom. Several different sets of basis
functions were systematically explored, starting with the original scheme of
Hylleraas. The most rapid convergence is found with a combination of negative
powers and a logarithm of the coordinate s = r_{1}+ r_{2}. At N=3091 terms we
pass the previous best calculation (Korobov's 25 decimal accuracy with N=5200
terms) and we stop at N=10257 with E = -2.90372 43770 34119 59831 11592 45194
40444 ...
Previous mathematical analysis sought to link the convergence rate of such
calculations to specific analytic properties of the functions involved. The
application of that theory to this new experimental data leaves a rather
frustrating situation, where we seem able to do little more than invoke vague
concepts, such as ``flexibility.'' We conclude that theoretical understanding
here lags well behind the power of available computing machinery.Comment: 15 page
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