12,889 research outputs found
Probing features of the Lee-Wick quantum electrodynamics
In this paper we discuss some aspects concerning the electromagnetic sector
of the abelian Lee-Wick (LW) quantum electrodynamics (QED). Using the Dirac's
theory of constrained systems, the higher-order canonical quantization of the
LW electromagnetism is performed. A quantum bound on the LW heavy mass is also
estimated using the best known measurement of the anomalous magnetic moment of
the electron. Finally it is shown that magnetic monopoles can coexist
peacefully in the LW scenario.Comment: Replaced with published versio
Wormholes in de Sitter branes
In this work we present a class of geometries which describes wormholes in a
Randall-Sundrum brane model, focusing on de Sitter backgrounds. Maximal
extensions of the solutions are constructed and their causal structures are
discussed. A perturbative analysis is developed, where matter and gravitational
perturbations are studied. Analytical results for the quasinormal spectra are
obtained and an extensive numerical survey is conducted. Our results indicate
that the wormhole geometries presented are stable.Comment: 10 pages, 7 figure
CHEMICAL AND PHYSICAL CHARACTERISTICS OF M. PSOAS MAIOR FROM ALENTEJANO PIGS AT A VARIOUS LIVE WEIGTHS
The present study was carried out to investigate the evolution of biochemical composition and physical traits of the chemical composition and physical characteristics of muscle Psoas major (PM adipose during growth of Alentejano pigs
Regular rotating black holes and the weak energy condition
We revisit here a recent work on regular rotating black holes. We introduce a
new mass function generalizing the commonly used Bardeen and Hayward mass
functions and extend the recently proposed solutions in order to accommodate a
cosmological constant . We discuss some aspects of the causal
structure (horizons) and the ergospheres of the new proposed solutions. We also
show that, in contrast with the spherically symmetrical case, the black hole
rotation will unavoidably lead to the violation of the weak energy condition
for any physically reasonable choice of the mass function, reinforcing the idea
the description of the interior region of a Kerr black hole is much more
challenging than in the Schwarzschild case.Comment: 8 pages, 3 figure
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