1 Optical analysis of doped PbTe samples using UV- VIS and...
... SCP model gave a satisfactory fit to the second derivatives of ε1(E) spectra [d2ε1(E)/dE2], but could not yield good fits to ε2(E) spectra. The MDF, on the other hand, gave results that were in excellent agreement with the experimental data for both ε(E) spectra and their derivatives [1]. Other diel ...
... SCP model gave a satisfactory fit to the second derivatives of ε1(E) spectra [d2ε1(E)/dE2], but could not yield good fits to ε2(E) spectra. The MDF, on the other hand, gave results that were in excellent agreement with the experimental data for both ε(E) spectra and their derivatives [1]. Other diel ...
The Collision Between The Milky Way And Andromeda
... 16% (Spergel et al. 2003). Since the Milky Way and Andromeda galaxy models only include baryons in the galactic disk and bulge components, they are far short of this value. We therefore set the Local Group medium to be 20% primordial gas, by mass, so that the entire region approaches the cosmic mean ...
... 16% (Spergel et al. 2003). Since the Milky Way and Andromeda galaxy models only include baryons in the galactic disk and bulge components, they are far short of this value. We therefore set the Local Group medium to be 20% primordial gas, by mass, so that the entire region approaches the cosmic mean ...
Science with the Constellation
... 1.2 The Ultimate Limits of Gravity Since their discovery, quasars and active galactic nuclei (AGN) have stood out as uniquely luminous objects in the Universe. Today we are confident that their ultimate power source is the release of gravitational energy sustained by an accretion disk, which is fee ...
... 1.2 The Ultimate Limits of Gravity Since their discovery, quasars and active galactic nuclei (AGN) have stood out as uniquely luminous objects in the Universe. Today we are confident that their ultimate power source is the release of gravitational energy sustained by an accretion disk, which is fee ...
Production and evolution of axion dark matter in the early universe
... when it was proposed. In the original model, the axion was “visible” in the sense that it gives some predictions for laboratory experiments. Unfortunately, no signature was observed, and the prototype axion model was ruled out soon after the proposal [15]. However, it was argued that models with hig ...
... when it was proposed. In the original model, the axion was “visible” in the sense that it gives some predictions for laboratory experiments. Unfortunately, no signature was observed, and the prototype axion model was ruled out soon after the proposal [15]. However, it was argued that models with hig ...
The environment of high-redshift AGN OLIMPIA JUDIT FOGASY
... the processes that engineered the tight correlations found between their supermassive black hole (SMBH) mass and bulge mass or velocity dispersion, the study of powerful, high-redshift active galactic nuclei (AGN) and their environment is crucial. As powerful high-z AGN are massive galaxies themselv ...
... the processes that engineered the tight correlations found between their supermassive black hole (SMBH) mass and bulge mass or velocity dispersion, the study of powerful, high-redshift active galactic nuclei (AGN) and their environment is crucial. As powerful high-z AGN are massive galaxies themselv ...
Beyond Einstein and E =mc - The General Science Journal
... Kala Rani Sharma, poet father Mr Dev Dutt Sharma and wife Anjana Sharma. Otherwise it would have been difficult to maintain enthusiasm over three decades on such topics. Also diligent efforts of staff of the press are gratefully acknowledged. Some people have years and years for criticism but really ...
... Kala Rani Sharma, poet father Mr Dev Dutt Sharma and wife Anjana Sharma. Otherwise it would have been difficult to maintain enthusiasm over three decades on such topics. Also diligent efforts of staff of the press are gratefully acknowledged. Some people have years and years for criticism but really ...
The Life and Work of Edward Emerson Barnard
... Only Frost was worried that Barnard might overdo it, and wrote to him: 'It is a pleasure to know that you are having such fine weather for work, but I hope you will not overdo, and you will give up some clear nights when you need sleep.'60 As usual, Barnard ignored this advice. Since there was no ru ...
... Only Frost was worried that Barnard might overdo it, and wrote to him: 'It is a pleasure to know that you are having such fine weather for work, but I hope you will not overdo, and you will give up some clear nights when you need sleep.'60 As usual, Barnard ignored this advice. Since there was no ru ...
Zero Point Energy
... Physicist Steven K. Lamoreaux, now of Los Alamos National Laboratory, performed an exacting, elegant experiment (while at the University of Washington in Seattle), which confirms within 5% the theoretical formula for the Casimir force, which was proposed in 1948. This is the force that is said to be ...
... Physicist Steven K. Lamoreaux, now of Los Alamos National Laboratory, performed an exacting, elegant experiment (while at the University of Washington in Seattle), which confirms within 5% the theoretical formula for the Casimir force, which was proposed in 1948. This is the force that is said to be ...
$doc.title
... Despite these advances, the field of cosmology was starved for data until quite recently. In the past decade, massive statistical surveys of galaxies and large-scale structure such as the Two-Degree Field (2dF) survey and the Sloan Digital Sky Survey (SDSS), combined with high-resolution observation ...
... Despite these advances, the field of cosmology was starved for data until quite recently. In the past decade, massive statistical surveys of galaxies and large-scale structure such as the Two-Degree Field (2dF) survey and the Sloan Digital Sky Survey (SDSS), combined with high-resolution observation ...
local - Physics
... The work contained herein would not have been possible without the guidance, support, and co-operation of my supervisors: Prof. Anthony G. Williams and Prof. Derek B. Leinweber, nor that of Prof. Anthony W. Thomas at Jefferson Lab, Virginia, USA. Their time and knowledge has been volunteered to seed ...
... The work contained herein would not have been possible without the guidance, support, and co-operation of my supervisors: Prof. Anthony G. Williams and Prof. Derek B. Leinweber, nor that of Prof. Anthony W. Thomas at Jefferson Lab, Virginia, USA. Their time and knowledge has been volunteered to seed ...
Teaching Tips Table of Contents - Hubble Deep Field
... Educators should allow approximately 45-55 minutes for the Orientation section of the activity and approximately 45-55 minutes for each of the activity’s four “Academy” levels. About 30-40 minutes should be allotted for students to complete the readings in the Deeper Views section. Depending on the ...
... Educators should allow approximately 45-55 minutes for the Orientation section of the activity and approximately 45-55 minutes for each of the activity’s four “Academy” levels. About 30-40 minutes should be allotted for students to complete the readings in the Deeper Views section. Depending on the ...
21_Testbank
... B) Galaxies were much bigger in the past since they had not contracted completely. C) Galaxies were closer together in the past because the universe was smaller. D) Galaxies attracted each other more strongly in the past because they were more massive; they had not yet turned most of their mass into ...
... B) Galaxies were much bigger in the past since they had not contracted completely. C) Galaxies were closer together in the past because the universe was smaller. D) Galaxies attracted each other more strongly in the past because they were more massive; they had not yet turned most of their mass into ...
PH607 – Galaxies
... remarkable trend: virtually all the galaxies they observed were moving away from our galaxy (redshifted) and the recession speed increased with distance. Hubble's first dataset included only a few dozen galaxies which were < 2 Mpc away but his basic conclusion has not changed as more and more gala ...
... remarkable trend: virtually all the galaxies they observed were moving away from our galaxy (redshifted) and the recession speed increased with distance. Hubble's first dataset included only a few dozen galaxies which were < 2 Mpc away but his basic conclusion has not changed as more and more gala ...
http://www.pd.infn.it/academy_board_819/pivato_giovanna_tesi.pdf
... was determined to be a power-law (Sν ∝ ν α ) with index α ∼ −0.5. A power law distribution cannot be generated from particles in thermal equilibrium described by Planck’s law. In 1953, Shklovskii associated the synchrotron unresolved radiation with remnants of unseen SN (Shklovskii, 1953), subsequen ...
... was determined to be a power-law (Sν ∝ ν α ) with index α ∼ −0.5. A power law distribution cannot be generated from particles in thermal equilibrium described by Planck’s law. In 1953, Shklovskii associated the synchrotron unresolved radiation with remnants of unseen SN (Shklovskii, 1953), subsequen ...
lecture course
... pressureless equation of state. This is what distinguishes it from dark energy, which makes up the other 70% or so. This dark matter must be cold in order to form galaxies, since hot dark matter (like neutrinos) will free-stream out of perturbations in the cosmological fluid at early times. By “cold ...
... pressureless equation of state. This is what distinguishes it from dark energy, which makes up the other 70% or so. This dark matter must be cold in order to form galaxies, since hot dark matter (like neutrinos) will free-stream out of perturbations in the cosmological fluid at early times. By “cold ...
Here - 21st International Conference on General Relativity and
... On the conditions for the formation of exotic compact objects from gravitational collapse (Daniele Malafarina) . . . . . . . . . . . . . . . . . Universal Walker metrics (Tomas Malek ) . . . . . . . . . . . . . . . . . . . The Cartan Algorithm in Higher Dimensions with Applications (David McNutt) . ...
... On the conditions for the formation of exotic compact objects from gravitational collapse (Daniele Malafarina) . . . . . . . . . . . . . . . . . Universal Walker metrics (Tomas Malek ) . . . . . . . . . . . . . . . . . . . The Cartan Algorithm in Higher Dimensions with Applications (David McNutt) . ...
Introduction
... to relatively isolated systems. As such, the sample is ideal for disentangling the internal and environmental processes driving evolution. The combination of ultraviolet, optical, near- and far-infrared imaging, nuclear and integrated optical spectroscopy, and atomic hydrogen emission line data, tra ...
... to relatively isolated systems. As such, the sample is ideal for disentangling the internal and environmental processes driving evolution. The combination of ultraviolet, optical, near- and far-infrared imaging, nuclear and integrated optical spectroscopy, and atomic hydrogen emission line data, tra ...
Dark energy
In physical cosmology and astronomy, dark energy is an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe. Dark energy is the most accepted hypothesis to explain the observations since the 1990s indicating that the universe is expanding at an accelerating rate. Assuming that the standard model of cosmology is correct, the best current measurements indicate that dark energy contributes 68.3% of the total energy in the present-day observable universe. The mass–energy of dark matter and ordinary matter contribute 26.8% and 4.9%, respectively, and other components such as neutrinos and photons contribute a very small amount. Again on a mass–energy equivalence basis, the density of dark energy (6.91 × 10−27 kg/m3) is very low, much less than the density of ordinary matter or dark matter within galaxies. However, it comes to dominate the mass–energy of the universe because it is uniform across space.Two proposed forms for dark energy are the cosmological constant, a constant energy density filling space homogeneously, and scalar fields such as quintessence or moduli, dynamic quantities whose energy density can vary in time and space. Contributions from scalar fields that are constant in space are usually also included in the cosmological constant. The cosmological constant can be formulated to be equivalent to vacuum energy. Scalar fields that do change in space can be difficult to distinguish from a cosmological constant because the change may be extremely slow.High-precision measurements of the expansion of the universe are required to understand how the expansion rate changes over time and space. In general relativity, the evolution of the expansion rate is parameterized by the cosmological equation of state (the relationship between temperature, pressure, and combined matter, energy, and vacuum energy density for any region of space). Measuring the equation of state for dark energy is one of the biggest efforts in observational cosmology today.Adding the cosmological constant to cosmology's standard FLRW metric leads to the Lambda-CDM model, which has been referred to as the ""standard model of cosmology"" because of its precise agreement with observations. Dark energy has been used as a crucial ingredient in a recent attempt to formulate a cyclic model for the universe.