Matter and antimatter in the same universe?
... relativity), or pictures like the Stationary Universe which seems not able to t a k e into account some experimental observations (like the red-shift, the 2.7K background radiation and the quasar distribution peak at (7 + 9) billion light-y). We will thus proceed in the framework of the Big Bang the ...
... relativity), or pictures like the Stationary Universe which seems not able to t a k e into account some experimental observations (like the red-shift, the 2.7K background radiation and the quasar distribution peak at (7 + 9) billion light-y). We will thus proceed in the framework of the Big Bang the ...
Limits of time in cosmology
... What does time mean in cosmology? Are there any physical conditions which must be satisfied in order to speak about cosmic time? If so, how far back can time be extrapolated while still maintaining it as a well-defined physical concept? We have studied these questions in a series of papers over the ...
... What does time mean in cosmology? Are there any physical conditions which must be satisfied in order to speak about cosmic time? If so, how far back can time be extrapolated while still maintaining it as a well-defined physical concept? We have studied these questions in a series of papers over the ...
The Inflation Debate - Physics Department, Princeton University
... growth spurt would have spread out energy until it was evenly dispersed and straightened out any curves and warps in space. When this period of inflation ended, the universe would have continued to expand at the more mellow pace of the original big bang theory but now with just the right conditions ...
... growth spurt would have spread out energy until it was evenly dispersed and straightened out any curves and warps in space. When this period of inflation ended, the universe would have continued to expand at the more mellow pace of the original big bang theory but now with just the right conditions ...
Review4
... Hint: Use Hubble’s law: V=H d and take the value of H from the book and the above value for V and solve for d. Make sure that you find d in the correct units. For this you may need to convert the units of Hubble’s constant H in the right units. Chapter 24-25: What is the significance of the large re ...
... Hint: Use Hubble’s law: V=H d and take the value of H from the book and the above value for V and solve for d. Make sure that you find d in the correct units. For this you may need to convert the units of Hubble’s constant H in the right units. Chapter 24-25: What is the significance of the large re ...
Radiation from Proxima Centauri
... Careful analysis of the spectrum shows that the surface temperature of Proxima Centauri is 3042 K. Use this information to show that the peak wavelength is approximately 106 m and label the peak wavelength of the spectrum with a more accurate figure. ...
... Careful analysis of the spectrum shows that the surface temperature of Proxima Centauri is 3042 K. Use this information to show that the peak wavelength is approximately 106 m and label the peak wavelength of the spectrum with a more accurate figure. ...
Types of Telescopes - NSTA Learning Center
... With his new 20x telescope he observed the Moon and discovered the four largest moons of Jupiter. He would go on to use his telescopes to study sunspots and the phases of Venus. Galileo’s observations revolutionized astronomy and changed our worldview ...
... With his new 20x telescope he observed the Moon and discovered the four largest moons of Jupiter. He would go on to use his telescopes to study sunspots and the phases of Venus. Galileo’s observations revolutionized astronomy and changed our worldview ...
PDF sample - Northern Central Hospital
... maintained with the spotless cleanliness of an ultra-purified laboratory clean room. It has to be. The slightest radioactive contaminants could mask the frustratingly small signal being searched for by the scores of scientists who monitor the tank with 11,200 phototubes — eerily resembling televisio ...
... maintained with the spotless cleanliness of an ultra-purified laboratory clean room. It has to be. The slightest radioactive contaminants could mask the frustratingly small signal being searched for by the scores of scientists who monitor the tank with 11,200 phototubes — eerily resembling televisio ...
POISE AND EVOLUTION OF THE GALAXY : STRUCTURE ,
... accelerating electric field (the effect however being spatially restricted to the strict vicinity of the magnetic poles) ; but that, actually, there is almost no matter to accelerate (from a neutron star !). If there was, through unlikely ionisation, the electrical energy thus produced would however ...
... accelerating electric field (the effect however being spatially restricted to the strict vicinity of the magnetic poles) ; but that, actually, there is almost no matter to accelerate (from a neutron star !). If there was, through unlikely ionisation, the electrical energy thus produced would however ...
Word
... The Big Bang theory of the Universe states that the Universe was created in a massive explosion from a point when space, time and matter were created. This event is thought to have occurred about 14 billion years ago. As the Universe expanded and cooled, first nucleons, then nuclei, atoms, molecules ...
... The Big Bang theory of the Universe states that the Universe was created in a massive explosion from a point when space, time and matter were created. This event is thought to have occurred about 14 billion years ago. As the Universe expanded and cooled, first nucleons, then nuclei, atoms, molecules ...
DSSU, the Non-Expanding Universe: Structure, Redshift, Distance
... The scaling factor problem underscores an annoying complication inherent in universal BB expansion: the dual-distance complication. It is important to realize that in standard cosmology there are actually two distances associated with a remote galaxy. Proponents of BB methodology, and those trying t ...
... The scaling factor problem underscores an annoying complication inherent in universal BB expansion: the dual-distance complication. It is important to realize that in standard cosmology there are actually two distances associated with a remote galaxy. Proponents of BB methodology, and those trying t ...
Mach`s Principle and the Concept of Mass
... giving off radiation. The resulting radiation has been identified with the cosmic microwave background radiation which has been found to be distributed throughout the universe in a pattern corresponding to the matter distribution. The value of inertial mass changes with distance from the center of t ...
... giving off radiation. The resulting radiation has been identified with the cosmic microwave background radiation which has been found to be distributed throughout the universe in a pattern corresponding to the matter distribution. The value of inertial mass changes with distance from the center of t ...
How do we know what stars are
... Why is the Hubble telescope better than one located on Earth? How old is the universe? Explain how the age of the universe is found. Explain how distance tells time in space. What Hubble's Law mean? Watch the following video on youtube.com, The History of the Universe in 10 minutes, https://www.yout ...
... Why is the Hubble telescope better than one located on Earth? How old is the universe? Explain how the age of the universe is found. Explain how distance tells time in space. What Hubble's Law mean? Watch the following video on youtube.com, The History of the Universe in 10 minutes, https://www.yout ...
Think about the universe
... a star is plotted against its surface temperature, which is deduced from its colour. When data for many stars are plotted, most of them, including our sun, fall into what is known as the main sequence. Exactly where a ...
... a star is plotted against its surface temperature, which is deduced from its colour. When data for many stars are plotted, most of them, including our sun, fall into what is known as the main sequence. Exactly where a ...
Lab 15 How Many Galaxies Are There in the
... 11. We have just calculated the total mass of galaxies in the Universe, and are halfway to our goal of figuring out the density of galactic matter in the Universe. Since density = M/V, and we now have M, we have to figure out V, the Volume of the Universe. This is a little more difficult than gettin ...
... 11. We have just calculated the total mass of galaxies in the Universe, and are halfway to our goal of figuring out the density of galactic matter in the Universe. Since density = M/V, and we now have M, we have to figure out V, the Volume of the Universe. This is a little more difficult than gettin ...
Document
... How is a continuous spectrum produced by a dense collection of atoms if each atom only produces a line spectrum? ...
... How is a continuous spectrum produced by a dense collection of atoms if each atom only produces a line spectrum? ...
The Physical Nature of Cosmic Accretion of Baryons and Dark Matter
... our assumed mass profile inside the halo. For example, using an isothermal profile instead of NFW gives results that are consistent at the ∼ 10% level. Figure 2 shows the predicted values of the enclosed overdensity. Throughout this paper, we define overdensities relative to the mean matter density, ...
... our assumed mass profile inside the halo. For example, using an isothermal profile instead of NFW gives results that are consistent at the ∼ 10% level. Figure 2 shows the predicted values of the enclosed overdensity. Throughout this paper, we define overdensities relative to the mean matter density, ...
Cosmology with the CBI
... The CBI Project is a collaboration between the California Institute of Technology, the Canadian Institute for Theoretical Astrophysics, the National Radio Astronomy Observatory, the University of Chicago, and the Universidad de Chile. The project has been supported by funds from the National Science ...
... The CBI Project is a collaboration between the California Institute of Technology, the Canadian Institute for Theoretical Astrophysics, the National Radio Astronomy Observatory, the University of Chicago, and the Universidad de Chile. The project has been supported by funds from the National Science ...
Science Says: What Scientific Evidence Can Say About the
... static state throughout all of time) and he made several adjustments to his theory to preserve that model. When astronomers discovered the expansion of the universe, however, Einstein rejected his proposed cosmological constant and called it "the greatest blunder of his scientific career."9 However, ...
... static state throughout all of time) and he made several adjustments to his theory to preserve that model. When astronomers discovered the expansion of the universe, however, Einstein rejected his proposed cosmological constant and called it "the greatest blunder of his scientific career."9 However, ...
Readings for Prof. Michael J. Crowe`s Two Sessions on The
... question makes no sense. What happened next? Maybe not next, but “0.000000000000000000000000000000000001 seconds after the Big Bang”: “The universe began with a vast explosion that generated space and time, and created all the matter and energy in the universe. What triggered this sudden expansion r ...
... question makes no sense. What happened next? Maybe not next, but “0.000000000000000000000000000000000001 seconds after the Big Bang”: “The universe began with a vast explosion that generated space and time, and created all the matter and energy in the universe. What triggered this sudden expansion r ...
–1– Order of Magnitude Astrophysics
... Each term involvement the square of a displacement averages to the mean square of the free path of a photon, which is denoted l2 . To within a factor of order unity, l is simply the mean free path of a photon. The cross terms in equation [7] involve averaging the cosine of the angle between the dire ...
... Each term involvement the square of a displacement averages to the mean square of the free path of a photon, which is denoted l2 . To within a factor of order unity, l is simply the mean free path of a photon. The cross terms in equation [7] involve averaging the cosine of the angle between the dire ...
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.