21,152 research outputs found
Lie nilpotency indices of symmetric elements under oriented involutions in group algebras
Let be a group and let be a field of characteristic different from 2.
Denote by the set of symmetric elements and by the
set of symmetric units, under an oriented classical involution of the group
algebra . We give some lower and upper bounds on the Lie nilpotency index
of and the nilpotency class of .Comment: Some corrected typos from version v2 and problems with the
bibliograph
Electromagnetic nucleon form factors from QCD sum rules
The electromagnetic form factors of the nucleon, in the space-like region,
are determined from three-point function Finite Energy QCD Sum Rules. The QCD
calculation is performed to leading order in perturbation theory in the chiral
limit, and to leading order in the non-perturbative power corrections. The
results for the Dirac form factor, , are in very good agreement with
data for both the proton and the neutron, in the currently accessible
experimental region of momentum transfers. This is not the case, though, for
the Pauli form factor , which has a soft -dependence
proportional to the quark condensate .Comment: Replaced Version. An error has been corrected in the numerical
evaluation of the Pauli form factor. This changes the results for F_2(q^2),
as well as the conclusion
The set of -units modulo
Let be a ring with identity, the group of units of
and a positive integer. We say that is -unit if
. Particularly, if the ring is , for a positive
integer , we will say that is a -unit modulo . We denote with
the set of -units modulo . By we
represent the number of -units modulo and with
the ratio of -units modulo
, where is the Euler phi function. Recently, S. K. Chebolu proved
that the solutions of the equation are the divisors of
. The main result of this work, is that for a given , we find the
positive integers such that . Finally, we give some
connections of this equation with Carmichael's numbers and two of its
generalizations: Kn\"odel numbers and generalized Carmichael numbers
Coral symbiodinium community composition across the Belize Mesoamerican barrier reef system is influenced by host species and thermal variability
Accepted manuscrip
Bayesian Analysis for Extracting Properties of the Nuclear Equation of State from Observational Data including Tidal Deformability from GW170817
We develop a Bayesian analysis method for selecting the most probable
equation of state under a set of constraints from compact star physics, which
now include the tidal deformability from GW170817. We apply this method for the
first time to a two-parameter family of hybrid equations of state that is based
on realistic models for the hadronic phase (KVORcut02) and the quark matter
phase (SFM) which produce a third family of hybrid stars in the
mass-radius diagram. One parameter () characterizes the screening of
the string tension in the string-flip model of quark matter while the other
() belongs to the mixed phase construction that mimics the
thermodynamics of pasta phases and includes the Maxwell construction as a
limiting case for . We present the corresponding results for
compact star properties like mass, radius and tidal deformabilities and use
empirical data for them in the newly developed Bayesian analysis method to
obtain the probabilities for the model parameters within their considered
range.Comment: 8 pages, 4 figures, version accepted for publication in univers
Universal Scaling in the Aging of the Strong Glass Former SiO
We show that the aging dynamics of a strong glass former displays a
strikingly simple scaling behavior, connecting the average dynamics with its
fluctuations, namely the dynamical heterogeneities. We perform molecular
dynamics simulations of SiO with BKS interactions, quenching the system
from high to low temperature, and study the evolution of the system as a
function of the waiting time measured from the instant of the
quench. We find that both the aging behavior of the dynamic susceptibility
and the aging behavior of the probability distribution of the local incoherent intermediate scattering function
can be described by simple scaling forms in terms of
the global incoherent intermediate scattering function . The scaling forms
are the same that have been found to describe the aging of several fragile
glass formers and that, in the case of , have been
also predicted theoretically. A thorough study of the length scales involved
highlights the importance of intermediate length scales. We also analyze
directly the scaling dependence on particle type and on wavevector , and
find that both the average and the fluctuations of the slow aging dynamics are
controlled by a unique aging clock, which is not only independent of the
wavevector , but is the same for O and Si atoms.Comment: 13 pages, 21 figures (postscript
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