Slides
... Some CMB anisotropies are created very recently: Integrated Sachs-Wolfe (ISW) effect Non-linear effects like Sunyaev-Zeldovich In some dark energy models, like tracking models, the dark energy density can change significantly, so that it is important at z=1000. ...
... Some CMB anisotropies are created very recently: Integrated Sachs-Wolfe (ISW) effect Non-linear effects like Sunyaev-Zeldovich In some dark energy models, like tracking models, the dark energy density can change significantly, so that it is important at z=1000. ...
The Early Universe and the Big Bang
... Regions which are now very far apart and no longer in causal contact were in causal contact before inflation Inflation pushed these regions really far apart, so now they are no longer in causal contact ...
... Regions which are now very far apart and no longer in causal contact were in causal contact before inflation Inflation pushed these regions really far apart, so now they are no longer in causal contact ...
PPT
... • Our vacuum can have unusual properties that one would not expect from Newton’s or Leibniz’ (or even Einstein’s) space. It now makes sense to ask, “Are the virtual particles in our vacuum aligned in some way?” Do the underlying equations of physics have any symmetry that is not manifested by the wo ...
... • Our vacuum can have unusual properties that one would not expect from Newton’s or Leibniz’ (or even Einstein’s) space. It now makes sense to ask, “Are the virtual particles in our vacuum aligned in some way?” Do the underlying equations of physics have any symmetry that is not manifested by the wo ...
Cosmology – The Origin and Evolution of the Universe
... • But ionized gas is opaque: So, we should see through cool transparent gas until our line-of-sight hits gas so young and so hot that it’s ionized and opaque. • When the Universe cooled to 3,000 degrees – protons and electrons combined and light was finally able to travel freely forever after • Thus ...
... • But ionized gas is opaque: So, we should see through cool transparent gas until our line-of-sight hits gas so young and so hot that it’s ionized and opaque. • When the Universe cooled to 3,000 degrees – protons and electrons combined and light was finally able to travel freely forever after • Thus ...
Big-Bang
... shouldn’t be there, yet there they sit. It’s hard to convey the depth of frustration that this simple fact induces among scientists.” James Trefill, The Dark Side of the Universe (New York: Charles Scribners’s Sons), pg. 55 ...
... shouldn’t be there, yet there they sit. It’s hard to convey the depth of frustration that this simple fact induces among scientists.” James Trefill, The Dark Side of the Universe (New York: Charles Scribners’s Sons), pg. 55 ...
Astrophysics * Glossary - Uplift Summit International
... In 1960 it was proposed that sometime during the early history of the Universe it was at a sufficiently high temperature to produce helium by fusion. In this process many high energy photons would be produced. The CMB (Cosmic Microwave Background Radiation) radiation was emitted only a few hundred t ...
... In 1960 it was proposed that sometime during the early history of the Universe it was at a sufficiently high temperature to produce helium by fusion. In this process many high energy photons would be produced. The CMB (Cosmic Microwave Background Radiation) radiation was emitted only a few hundred t ...
The Early Universe PowerPoint
... • Mass & energy formed during inflation • Most matter & antimatter annihilated each other • Neutrinos & helium are primordial fireball relics • Galaxies formed from early density variations • Grand Unified Theories unite all physical forces ...
... • Mass & energy formed during inflation • Most matter & antimatter annihilated each other • Neutrinos & helium are primordial fireball relics • Galaxies formed from early density variations • Grand Unified Theories unite all physical forces ...
Problem Set # 8: The Last Problem Set Due Wednesday, December
... 1) [20 points] The dim little star Proxima Centauri, the Sun’s nearest neighbor among the stars, has a mass M = 0.12Msun , where Msun is the Sun’s mass. It has a luminosity L = 0.00014Lsun , where Lsun is the Sun’s luminosity. Like the Sun, Proxima Centauri is powered by the fusion of hydrogen into ...
... 1) [20 points] The dim little star Proxima Centauri, the Sun’s nearest neighbor among the stars, has a mass M = 0.12Msun , where Msun is the Sun’s mass. It has a luminosity L = 0.00014Lsun , where Lsun is the Sun’s luminosity. Like the Sun, Proxima Centauri is powered by the fusion of hydrogen into ...
Nov 2009
... (h) State the two quantities that need to be measured in order to use a Cepheid variable as a “standard candle” to determine the distance to the galaxy in which the Cepheid is located. ...
... (h) State the two quantities that need to be measured in order to use a Cepheid variable as a “standard candle” to determine the distance to the galaxy in which the Cepheid is located. ...
Dark Matter Dark Energy The History of the Universe More of the
... Light can be converted into mass by the process of _____. ...
... Light can be converted into mass by the process of _____. ...
100 $100 $100 $100 $100 $100 $200 $200 $200 $200 $200 $200
... Light can be converted into mass by the process of _____. ...
... Light can be converted into mass by the process of _____. ...
Universe and Galaxy Short Study Guide
... Match each item with the correct statement below. a. inflationary universe e. steady-state theory b. cosmology f. Hubble constant c. Big Bang theory g. active galactic nucleus d. cosmic background radiation h. superclusters ____ 7. Core of a galaxy in which highly energetic objects or activities are ...
... Match each item with the correct statement below. a. inflationary universe e. steady-state theory b. cosmology f. Hubble constant c. Big Bang theory g. active galactic nucleus d. cosmic background radiation h. superclusters ____ 7. Core of a galaxy in which highly energetic objects or activities are ...
physics_cosmic_engine - HSC Guru
... The early models were limited by the technology that was available at the time. For example, since the development of the telescope, more information about the universe has been collected. ...
... The early models were limited by the technology that was available at the time. For example, since the development of the telescope, more information about the universe has been collected. ...
No Slide Title
... the history of the universe. Why didn’t it take over the expansion billions of years ago, before galaxies (and us) had the chance to form? Or why didn’t it wait until the far future, so today we would never have detected it? This is called the coincidence problem. ...
... the history of the universe. Why didn’t it take over the expansion billions of years ago, before galaxies (and us) had the chance to form? Or why didn’t it wait until the far future, so today we would never have detected it? This is called the coincidence problem. ...
Temperature–Time Relation
... where MeV stands for mega-electron-volt. This version is the key to determining the types of physical process happening at different stages of the Universe's evolution. For example, the binding energy of typical light nuclei, such as helium-4, is around 1 MeV per particle. Hence when the Universe w ...
... where MeV stands for mega-electron-volt. This version is the key to determining the types of physical process happening at different stages of the Universe's evolution. For example, the binding energy of typical light nuclei, such as helium-4, is around 1 MeV per particle. Hence when the Universe w ...
Lecture17
... • Not bad. It takes another year to slow down to zero velocity for turning around. Same for the return trip. Coasting at 94% of c, a trip to the nearest star (4 light-years out) takes about a decade. And time dilation will shorten the trip further for the astronaut. • The catch: The time traveler ex ...
... • Not bad. It takes another year to slow down to zero velocity for turning around. Same for the return trip. Coasting at 94% of c, a trip to the nearest star (4 light-years out) takes about a decade. And time dilation will shorten the trip further for the astronaut. • The catch: The time traveler ex ...
hot
... energetic motion of the particles, or the nature of light present – not in human terms of ‘how hot it would feel!’ These are unimaginably high temperatures. ...
... energetic motion of the particles, or the nature of light present – not in human terms of ‘how hot it would feel!’ These are unimaginably high temperatures. ...
The Big Bang Theory - Warren County Schools
... A crucial moment in the creation of the universe was when the atoms that were present became neutral and the radiation was able to flow through it and expand with the universe. This allowed matter to begin clumping to form the structures we observe in the universe. ...
... A crucial moment in the creation of the universe was when the atoms that were present became neutral and the radiation was able to flow through it and expand with the universe. This allowed matter to begin clumping to form the structures we observe in the universe. ...
Class 28, 27 July
... • Nuclei try to collapse (gravity), photons push back (pressure) • This leads to OSCILLATIONS! • Size of oscillations measures geometry of universe (know physical size, angle, so can measure geometry) ...
... • Nuclei try to collapse (gravity), photons push back (pressure) • This leads to OSCILLATIONS! • Size of oscillations measures geometry of universe (know physical size, angle, so can measure geometry) ...
Faux Final
... 4) Describe circumpolar stars and give the range of declinations in which circumpolar stars exist as seen from latitudes 0°, 10°, 30°, 60°, and 90°. 5) List the 7 common wavelength regimes of light in wavelength order. Indicate which transmit through the earth's atmosphere. 6) Sketch an ellipse as a ...
... 4) Describe circumpolar stars and give the range of declinations in which circumpolar stars exist as seen from latitudes 0°, 10°, 30°, 60°, and 90°. 5) List the 7 common wavelength regimes of light in wavelength order. Indicate which transmit through the earth's atmosphere. 6) Sketch an ellipse as a ...
Cosmology
... Cosmic background radiation is the afterglow of the Big Bang • The cosmic microwave background radiation, corresponding to a temperature of 2.7 K at the present day, is the greatly redshifted remnant of the hot universe as it existed about 380,000 years after the Big Bang • During the first 380,000 ...
... Cosmic background radiation is the afterglow of the Big Bang • The cosmic microwave background radiation, corresponding to a temperature of 2.7 K at the present day, is the greatly redshifted remnant of the hot universe as it existed about 380,000 years after the Big Bang • During the first 380,000 ...
CMBR and BH evaporation
... Meanwhile, we cannot consider such a process without taking into account the BH’s real environment. Particularly, one has to account some counteraction to its evaporation due to cosmic microwave background radiation (CMBR) that BH absorbs. Generally, a role of a matter can be more than this one of C ...
... Meanwhile, we cannot consider such a process without taking into account the BH’s real environment. Particularly, one has to account some counteraction to its evaporation due to cosmic microwave background radiation (CMBR) that BH absorbs. Generally, a role of a matter can be more than this one of C ...
1. a) Astronomers use the parallax method to measure
... b) Instead of the parallax method, we use the standard candle method to measure the distance to stars in other galaxies. In particular, we use the standard candle method to measure the distances to Cepheid variable stars in other galaxies. What is special about Cepheid variable stars that makes them ...
... b) Instead of the parallax method, we use the standard candle method to measure the distance to stars in other galaxies. In particular, we use the standard candle method to measure the distances to Cepheid variable stars in other galaxies. What is special about Cepheid variable stars that makes them ...
Our Expanding Universe File
... came to be. Several models explaining the origin of the universe have been proposed and scientists have attempted to find evidence either supporting or disproving these theories. There are three models that are supported by the scientific community. One model states that the universe has always look ...
... came to be. Several models explaining the origin of the universe have been proposed and scientists have attempted to find evidence either supporting or disproving these theories. There are three models that are supported by the scientific community. One model states that the universe has always look ...
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.