15 research outputs found
Description of Supernova Data in Conformal Cosmology without Cosmological Constant
We consider cosmological consequences of a conformal invariant formulation of
Einstein's General Relativity where instead of the scale factor of the spatial
metrics in the action functional a massless scalar (dilaton) field occurs which
scales all masses including the Planck mass. Instead of the expansion of the
universe we get the Hoyle-Narlikar type of mass evolution, where the
temperature history of the universe is replaced by the mass history. We show
that this conformal invariant cosmological model gives a satisfactory
description of the new supernova Ia data for the effective magnitude - redshift
relation without a cosmological constant and make a prediction for the
high-redshift behavior which deviates from that of standard cosmology for
.Comment: 13 pages, 1 figure, includes discussion of SN1997ff, text revise
Perfect Absorption of a Focused Light Beam by a Single Nanoparticle
Absorption of electromagnetic energy by a dissipative material is one of the most fundamental electromagnetic processes that underlies a plethora of applied problems, including sensing, radar detection, wireless power transfer, and photovoltaics. Common wisdom is that a finite dissipative object illuminated by a plane wave removes only a finite amount of the wave\u27s energy flux, which is determined by the object\u27s absorption cross-section. Thus, it is of fundamental interest to see if any far-field waveform can be perfectly absorbed by a finite object. Here, it is theoretically demonstrated that a precisely tailored light beam containing only far-field components can be perfectly absorbed by a finite scatterer on a substrate. The self-consistent scattering problem in the dipole approximation is analytically solved and finds a closed-form expression for the spatial spectrum of the incident field and the required complex polarizability of the particle. All analytical predictions are confirmed with full-wave simulations. The results introduce a qualitatively novel class of perfect absorption phenomena in electromagnetics and other wave processes