17 research outputs found
The Cosmic Microwave Background and Particle Physics
In forthcoming years, connections between cosmology and particle physics will
be made increasingly important with the advent of a new generation of cosmic
microwave background (CMB) experiments. Here, we review a number of these
links. Our primary focus is on new CMB tests of inflation. We explain how the
inflationary predictions for the geometry of the Universe and primordial
density perturbations will be tested by CMB temperature fluctuations, and how
the gravitational waves predicted by inflation can be pursued with the CMB
polarization. The CMB signatures of topological defects and primordial magnetic
fields from cosmological phase transitions are also discussed. Furthermore, we
review current and future CMB constraints on various types of dark matter (e.g.
massive neutrinos, weakly interacting massive particles, axions, vacuum
energy), decaying particles, the baryon asymmetry of the Universe,
ultra-high-energy cosmic rays, exotic cosmological topologies, and other new
physics.Comment: 43 pages. To appear in Annual Reviews of Nuclear and Particle Scienc
Quantum Spacetime Phenomenology
I review the current status of phenomenological programs inspired by
quantum-spacetime research. I stress in particular the significance of results
establishing that certain data analyses provide sensitivity to effects
introduced genuinely at the Planck scale. And my main focus is on
phenomenological programs that managed to affect the directions taken by
studies of quantum-spacetime theories.Comment: 125 pages, LaTex. This V2 is updated and more detailed than the V1,
particularly for quantum-spacetime phenomenology. The main text of this V2 is
about 25% more than the main text of the V1. Reference list roughly double
Quantum confinement effects observed by the photoluminescence of SiOx/SiO2 multilayers
Spectral and decay features related to the red emission from Si nanocrystals were investigated by time-resolved
photoluminescence spectra carried out on SiOx/SiO2 nanosized multilayers. On decreasing the SiOx thickness from 8.4 nm to 2.2 nm this luminescence band exhibits a blue-shift from 1.65 eV to 1.75 eV and its lifetime increases from 12μs to 17 μs. These results are discussed on the basis of previous models proposed in literature and
agree with quantum confinement effects arising from differently sized Si nanocrystals in our samples