ppt - RESCEU
... This was used to test for the Gaussianity of the primordial density field, which is one of the major predictions of the simple inflationary scenarios. 2. Recently, topology of galaxy distribution at non-linear scales is being used to constrain the galaxy formation mechanisms and cosmological paramet ...
... This was used to test for the Gaussianity of the primordial density field, which is one of the major predictions of the simple inflationary scenarios. 2. Recently, topology of galaxy distribution at non-linear scales is being used to constrain the galaxy formation mechanisms and cosmological paramet ...
Hubble Redshift - at www.arxiv.org.
... Recent measurements of Hubble redshift from supernovae are inconsistent with the standard theoretical model of an expanding Friedmann universe. Figure 1 shows the Hubble redshift for 37 supernovae measured by Riess et al.1 illustrating that a positive cosmological constant must be added to the equat ...
... Recent measurements of Hubble redshift from supernovae are inconsistent with the standard theoretical model of an expanding Friedmann universe. Figure 1 shows the Hubble redshift for 37 supernovae measured by Riess et al.1 illustrating that a positive cosmological constant must be added to the equat ...
OLIMPO
... • For each cluster, applying deprojection algorithms to the SZ and X images (see eg Zaroubi et al. 1999), and assuming hydrostatic equilibrium, it is possible to derive the gas profile and the total (including dark) mass of the cluster. • The presence of 4 channels (and especially the 1.3 mm one) is ...
... • For each cluster, applying deprojection algorithms to the SZ and X images (see eg Zaroubi et al. 1999), and assuming hydrostatic equilibrium, it is possible to derive the gas profile and the total (including dark) mass of the cluster. • The presence of 4 channels (and especially the 1.3 mm one) is ...
Document
... Gaseous Emission Continuum flux emitted vs wavelength in volume V is Fλ = Ne N+ γλ(Te) V ergs s-1 Ǻ-1 Ne & N+ are the electron and ion density and γλ(Te) is the continuous emission coefficient Hβ recombination line flux is FHβ = N(H0) [αHβeff(Te) / αE(Te)] 4.09 x 10 -12 ergs s -1 the numerical fact ...
... Gaseous Emission Continuum flux emitted vs wavelength in volume V is Fλ = Ne N+ γλ(Te) V ergs s-1 Ǻ-1 Ne & N+ are the electron and ion density and γλ(Te) is the continuous emission coefficient Hβ recombination line flux is FHβ = N(H0) [αHβeff(Te) / αE(Te)] 4.09 x 10 -12 ergs s -1 the numerical fact ...
Unification of Gravity and Electromagnetism I: Mach`s Principle and
... This is the form associated with Galileo’s law of falling bodies and Newton’s theory of gravity which uses the equality of gravitational and inertial mass and was confirmed to high precision by the Eötvös experiment. In this form it is usually referred to as the Weak Equivalence Principle (WEP). S ...
... This is the form associated with Galileo’s law of falling bodies and Newton’s theory of gravity which uses the equality of gravitational and inertial mass and was confirmed to high precision by the Eötvös experiment. In this form it is usually referred to as the Weak Equivalence Principle (WEP). S ...
Topic 4 - The University of Sheffield
... ‣ But if the Universe is filled with a lot of this stuff then stars should be contaminated with significant abundance of “Metals”. This is not seen. We see mainly hydrogen again. ‣ Also rocks and dust can be observed by obscuration of background light. It is actually hard to hide in the Universe. It ...
... ‣ But if the Universe is filled with a lot of this stuff then stars should be contaminated with significant abundance of “Metals”. This is not seen. We see mainly hydrogen again. ‣ Also rocks and dust can be observed by obscuration of background light. It is actually hard to hide in the Universe. It ...
Observational Evidence for Dark Matter Simona Murgia, SLAC-KIPAC XXXIX SLAC Summer Institute
... Relic of a time in the early Universe when matter and radiation decoupled (protons and electron form neutral hydrogen and become transparent to photons, ~100,000s years after Big Bang, ~ eV) Universe was isotropic and homogeneous at large scales Very small temperature fluctuations, too small to evol ...
... Relic of a time in the early Universe when matter and radiation decoupled (protons and electron form neutral hydrogen and become transparent to photons, ~100,000s years after Big Bang, ~ eV) Universe was isotropic and homogeneous at large scales Very small temperature fluctuations, too small to evol ...
Gravitational waves - LIGO
... GWs aren’t just a new band, they’re a new spectrum, with very different and complementary properties to EM waves. • Vibrations of space-time, not in space-time • Emitted by coherent motion of huge masses moving at near light-speed; not vibrations of electrons in atoms • Can’t be absorbed, scattered, ...
... GWs aren’t just a new band, they’re a new spectrum, with very different and complementary properties to EM waves. • Vibrations of space-time, not in space-time • Emitted by coherent motion of huge masses moving at near light-speed; not vibrations of electrons in atoms • Can’t be absorbed, scattered, ...
Some FAQs and Answers for the Big Bang, Dark Matter, and Dark
... temperature exceeds 3000 Kelvin. Atomic Hydrogen is ionized at this temperature, so before this time, there were very few atoms. Rather, the Universe was a plasma of protons and electrons, and perhaps other particles. Light does not propagate through a plasma, so the Universe was opaque. As the Univ ...
... temperature exceeds 3000 Kelvin. Atomic Hydrogen is ionized at this temperature, so before this time, there were very few atoms. Rather, the Universe was a plasma of protons and electrons, and perhaps other particles. Light does not propagate through a plasma, so the Universe was opaque. As the Univ ...
History of IGM (C. Carilli)
... Weak correlation of L_FIR – M_B? •M_B > -26: 10% detected at 250 GHz mJy sensitivity •M_B < -26: 30% detected ...
... Weak correlation of L_FIR – M_B? •M_B > -26: 10% detected at 250 GHz mJy sensitivity •M_B < -26: 30% detected ...
Eternal Inflation
... In the standard big bang theory there is no explanation whatever for this uniformity. In fact, one can even show that within the context of the standard big bang theory, no explanation for this uniformity is possible. To see this, we need to understand a little about how this cosmic background radia ...
... In the standard big bang theory there is no explanation whatever for this uniformity. In fact, one can even show that within the context of the standard big bang theory, no explanation for this uniformity is possible. To see this, we need to understand a little about how this cosmic background radia ...
Lecture 21: The Doppler effect - Harvard University Department of
... At an early enough time, the universe was so hot that the thermal energy was enough to ionize atoms. At this time, the universe was essentially a plasma. In a plasma, photons cannot get very far without hitting a free electron or proton, so the universe is opaque. The ionization energy of atoms is a ...
... At an early enough time, the universe was so hot that the thermal energy was enough to ionize atoms. At this time, the universe was essentially a plasma. In a plasma, photons cannot get very far without hitting a free electron or proton, so the universe is opaque. The ionization energy of atoms is a ...
20 – N10/4/PHYSI/SP3/ENG/TZ0/XX Option E
... (f ) The surface temperature of both PA and PB is of the order of 104 K. The luminosity of PA is of the order of 10LS, where LS is the luminosity of the Sun. The diagram shows the grid of a Hertzsprung–Russell diagram. ...
... (f ) The surface temperature of both PA and PB is of the order of 104 K. The luminosity of PA is of the order of 10LS, where LS is the luminosity of the Sun. The diagram shows the grid of a Hertzsprung–Russell diagram. ...
unit p1 – universal physics checklist
... Describe the role of gravity in the life cycle of star Describe how the evolution of stars with a mass larger than the Sun is different, and may end in a black hole or neutron star Demonstrate an understanding of the Steady State and Big Bang theories Describe evidence supporting the Big Bang theory ...
... Describe the role of gravity in the life cycle of star Describe how the evolution of stars with a mass larger than the Sun is different, and may end in a black hole or neutron star Demonstrate an understanding of the Steady State and Big Bang theories Describe evidence supporting the Big Bang theory ...
Angular Momentum of Dark Matter Black Holes
... With no WIMP one is led to astrophysical MACHOs and then confronted with the constraint from BBN that no more than 20% of the DM can be baryonic. This means that to make 100% of the DM we cannot use compact objects such as white dwarfs, neutron stars, brown dwarfs and unassociated planets. Nor is it ...
... With no WIMP one is led to astrophysical MACHOs and then confronted with the constraint from BBN that no more than 20% of the DM can be baryonic. This means that to make 100% of the DM we cannot use compact objects such as white dwarfs, neutron stars, brown dwarfs and unassociated planets. Nor is it ...
File
... use relative units; units that we compare the distance to something we are familiar with. We have already seen the light-year (the distance light travels in 1 year). We use this when referring to the size of galaxies, or distance to stars. When dealing with smaller distances, inside the solar system ...
... use relative units; units that we compare the distance to something we are familiar with. We have already seen the light-year (the distance light travels in 1 year). We use this when referring to the size of galaxies, or distance to stars. When dealing with smaller distances, inside the solar system ...
Document
... (1977) and Lucy (1977). In the SPH prescription, the fluid is discretized into individual particles that are smoothed. This means that the relevant properties of the fluid that are represented by each particle are distributed smoothly in space around the particle. Then, the value of each relevant qu ...
... (1977) and Lucy (1977). In the SPH prescription, the fluid is discretized into individual particles that are smoothed. This means that the relevant properties of the fluid that are represented by each particle are distributed smoothly in space around the particle. Then, the value of each relevant qu ...
22_Testbank
... perfect thermal radiation spectrum? A) The background radiation came from the heat of the universe, with a peak corresponding to the temperature of the universe. B) The spectrum of pure hydrogen is a perfect thermal radiation spectrum. C) The spectrum of 75 percent hydrogen and 25 percent helium is ...
... perfect thermal radiation spectrum? A) The background radiation came from the heat of the universe, with a peak corresponding to the temperature of the universe. B) The spectrum of pure hydrogen is a perfect thermal radiation spectrum. C) The spectrum of 75 percent hydrogen and 25 percent helium is ...
valenica_2014_planetarium2
... dome. Squashing the dome of course leads to distortions that are not seen in the planetarium dome. ...
... dome. Squashing the dome of course leads to distortions that are not seen in the planetarium dome. ...
Radio Astu~nmy I Q ~$apt~
... other authors has been resolved in favor of the radio data. A complete account of the data has also been published. 4 The derived value of the Hubble Constant depends upon lens model and mean matter density in the universe. Our derived values fall between 42 and 69 km/sec/Mpc. The method is complete ...
... other authors has been resolved in favor of the radio data. A complete account of the data has also been published. 4 The derived value of the Hubble Constant depends upon lens model and mean matter density in the universe. Our derived values fall between 42 and 69 km/sec/Mpc. The method is complete ...
Chapter 6 The inflationary universe In this chapter, we encounter a
... the cosmic background radiation known to be necessary for the seeding of the galaxies. Such inhomogeneities had not yet been observed experimentally; however, theoreticians had long predicted the amplitude and shape of non-uniformities in density that could give rise to today’s structures (known as ...
... the cosmic background radiation known to be necessary for the seeding of the galaxies. Such inhomogeneities had not yet been observed experimentally; however, theoreticians had long predicted the amplitude and shape of non-uniformities in density that could give rise to today’s structures (known as ...
Observations of Near Infrared Extragalactic Background (NIR_EBL)
... thermal emission from IPD l>3.5mm • Milky Way, integrated star light ・It is important to resolve and remove as faint stars as possible. ・Smaller beam is better to avoid confusion IRTS/NIRS: 8 arcmin COBE/DIRBE: 0.7 degree ...
... thermal emission from IPD l>3.5mm • Milky Way, integrated star light ・It is important to resolve and remove as faint stars as possible. ・Smaller beam is better to avoid confusion IRTS/NIRS: 8 arcmin COBE/DIRBE: 0.7 degree ...
Document
... – Gravity should unify with the GUTs force at very high energies. – Much higher than in any possible accelerator. accelerator – However, these energies could occur in the early Universe Universe. ...
... – Gravity should unify with the GUTs force at very high energies. – Much higher than in any possible accelerator. accelerator – However, these energies could occur in the early Universe Universe. ...
Expanding Universe Lab
... The Hubble Law tells us that our Universe is expanding. We observe galaxies, find their distances and their velocities, and find that they are all moving away from us. The more distant the galaxy, the faster it is moving away. From this information, we can estimate the age of our Universe. We assume ...
... The Hubble Law tells us that our Universe is expanding. We observe galaxies, find their distances and their velocities, and find that they are all moving away from us. The more distant the galaxy, the faster it is moving away. From this information, we can estimate the age of our Universe. We assume ...
Cosmic microwave background
The cosmic microwave background (CMB) is the thermal radiation left over from the time of recombination in Big Bang cosmology. In older literature, the CMB is also variously known as cosmic microwave background radiation (CMBR) or ""relic radiation."" The CMB is a cosmic background radiation that is fundamental to observational cosmology because it is the oldest light in the universe, dating to the epoch of recombination. With a traditional optical telescope, the space between stars and galaxies (the background) is completely dark. However, a sufficiently sensitive radio telescope shows a faint background glow, almost exactly the same in all directions, that is not associated with any star, galaxy, or other object. This glow is strongest in the microwave region of the radio spectrum. The accidental discovery of CMB in 1964 by American radio astronomers Arno Penzias and Robert Wilson was the culmination of work initiated in the 1940s, and earned the discoverers the 1978 Nobel Prize.The CMB is a snapshot of the oldest light in our Universe, imprinted on the sky when the Universe was just 380,000 years old. It shows tiny temperature fluctuations that correspond to regions of slightly different densities, representing the seeds of all future structure: the stars and galaxies of today.The CMB is well explained as radiation left over from an early stage in the development of the universe, and its discovery is considered a landmark test of the Big Bang model of the universe. When the universe was young, before the formation of stars and planets, it was denser, much hotter, and filled with a uniform glow from a white-hot fog of hydrogen plasma. As the universe expanded, both the plasma and the radiation filling it grew cooler. When the universe cooled enough, protons and electrons combined to form neutral atoms. These atoms could no longer absorb the thermal radiation, and so the universe became transparent instead of being an opaque fog. Cosmologists refer to the time period when neutral atoms first formed as the recombination epoch, and the event shortly afterwards when photons started to travel freely through space rather than constantly being scattered by electrons and protons in plasma is referred to as photon decoupling. The photons that existed at the time of photon decoupling have been propagating ever since, though growing fainter and less energetic, since the expansion of space causes their wavelength to increase over time (and wavelength is inversely proportional to energy according to Planck's relation). This is the source of the alternative term relic radiation. The surface of last scattering refers to the set of points in space at the right distance from us so that we are now receiving photons originally emitted from those points at the time of photon decoupling.Precise measurements of the CMB are critical to cosmology, since any proposed model of the universe must explain this radiation. The CMB has a thermal black body spectrum at a temperature of 7000272548000000000♠2.72548±0.00057 K. The spectral radiance dEν/dν peaks at 160.2 GHz, in the microwave range of frequencies. (Alternatively if spectral radiance is defined as dEλ/dλ then the peak wavelength is 1.063 mm.) The glow is very nearly uniform in all directions, but the tiny residual variations show a very specific pattern, the same as that expected of a fairly uniformly distributed hot gas that has expanded to the current size of the universe. In particular, the spectral radiance at different angles of observation in the sky contains small anisotropies, or irregularities, which vary with the size of the region examined. They have been measured in detail, and match what would be expected if small thermal variations, generated by quantum fluctuations of matter in a very tiny space, had expanded to the size of the observable universe we see today. This is a very active field of study, with scientists seeking both better data (for example, the Planck spacecraft) and better interpretations of the initial conditions of expansion. Although many different processes might produce the general form of a black body spectrum, no model other than the Big Bang has yet explained the fluctuations. As a result, most cosmologists consider the Big Bang model of the universe to be the best explanation for the CMB.The high degree of uniformity throughout the observable universe and its faint but measured anisotropy lend strong support for the Big Bang model in general and the ΛCDM (""Lambda Cold Dark Matter"") model in particular. Moreover, the fluctuations are coherent on angular scales that are larger than the apparent cosmological horizon at recombination. Either such coherence is acausally fine-tuned, or cosmic inflation occurred.