Document
... the anthropic coincidences The Copernican principle "However we are not able to make cosmological models without some admixture of ideology. In the earliest cosmologies, man placed himself in a commanding position at the centre of the universe. Since the time of Copernicus we have been steadily demo ...
... the anthropic coincidences The Copernican principle "However we are not able to make cosmological models without some admixture of ideology. In the earliest cosmologies, man placed himself in a commanding position at the centre of the universe. Since the time of Copernicus we have been steadily demo ...
Problem Set 3
... larger charged cylindrical shell. Both are nonconducting and thin and have uniform surface charge densities on their outer surfaces. Figure b gives the radial component E of the electric field versus radial distance r from the common axis. The vertical axis scale is set by ES 3.0 103 N/C. What i ...
... larger charged cylindrical shell. Both are nonconducting and thin and have uniform surface charge densities on their outer surfaces. Figure b gives the radial component E of the electric field versus radial distance r from the common axis. The vertical axis scale is set by ES 3.0 103 N/C. What i ...
Dark Matter
... But when you apply these principles the entire universe, the whole thing should be theoretically be falling apart. Each galaxy revolves around its central point, and they should all be floating away from one another. And yet there is a central point that was found by Vera Rubin in the late 1970s, a ...
... But when you apply these principles the entire universe, the whole thing should be theoretically be falling apart. Each galaxy revolves around its central point, and they should all be floating away from one another. And yet there is a central point that was found by Vera Rubin in the late 1970s, a ...
Dernières Nouvelles de l`Univers
... Positron excess in cosmic rays are not related to DM physics but to astrophysical sources and astrophysical mechanisms and can be explained by them ...
... Positron excess in cosmic rays are not related to DM physics but to astrophysical sources and astrophysical mechanisms and can be explained by them ...
Chern-Simons Inflation and Baryogenesis?
... Violation of stastical isotropy, nongaussianity, parity violation in CMB) ...
... Violation of stastical isotropy, nongaussianity, parity violation in CMB) ...
A n A n c i e n... How Astronomers Know the Vast Scale of Cosmic Time
... human history is a mere blink of an eye in comparison. We also provide some references to classroom activities, and resources for further exploration of some the astronomical ideas we discuss. As part of our discussion, we want to emphasize the methods by which scientists study cosmic age and evolut ...
... human history is a mere blink of an eye in comparison. We also provide some references to classroom activities, and resources for further exploration of some the astronomical ideas we discuss. As part of our discussion, we want to emphasize the methods by which scientists study cosmic age and evolut ...
How to create a universe - Philsci
... the Cabibbo-Kobayashi-Maskawa (CKM) matrix. By convention, the mixing is expressed in terms of the {d, s, b} quark flavours. The bundle which represents the generalisation of these three quark flavours is σd ⊕ σs ⊕ σb , where each summand is a copy of the Dirac spinor bundle σ. Different mixtures of ...
... the Cabibbo-Kobayashi-Maskawa (CKM) matrix. By convention, the mixing is expressed in terms of the {d, s, b} quark flavours. The bundle which represents the generalisation of these three quark flavours is σd ⊕ σs ⊕ σb , where each summand is a copy of the Dirac spinor bundle σ. Different mixtures of ...
The Mystery of the Cosmological Constant
... UNIVERSE with a large cosmological constant would be vastly different from the exist ing one. Here an artist has painted a scene as it might appear if the constant were as large as theoretical estimates suggest it could be. The illustration is based on a positive value for the constant on the order ...
... UNIVERSE with a large cosmological constant would be vastly different from the exist ing one. Here an artist has painted a scene as it might appear if the constant were as large as theoretical estimates suggest it could be. The illustration is based on a positive value for the constant on the order ...
Freezing of Reality: Is Flow of Time Real?
... According to some hypotheses, there is no sense talking about time before the beginning of the universe. In other words, time has no “beginning”: it emerges in a certain region of space-time (close to that what we call the Big Bang) from one of four dimensions that have a spatial character (Hawking, ...
... According to some hypotheses, there is no sense talking about time before the beginning of the universe. In other words, time has no “beginning”: it emerges in a certain region of space-time (close to that what we call the Big Bang) from one of four dimensions that have a spatial character (Hawking, ...
wk11noQ
... regions” marking areas of intense star formation activity. HII regions tend to lie along spiral arms. • Radiation from hot, young stars causes the gas to be ionized. The cascade of electrons down atomic energy levels results in an emission line spectrum. Examples of emission lines in the ultraviolet ...
... regions” marking areas of intense star formation activity. HII regions tend to lie along spiral arms. • Radiation from hot, young stars causes the gas to be ionized. The cascade of electrons down atomic energy levels results in an emission line spectrum. Examples of emission lines in the ultraviolet ...
NAME CODE
... insulator, and a cylindrical outer conductor (“copper sheath”), all coaxial with each other. For protection, the cable also has a plastic sheath. Figure (B) shows a piece of this cable of length L and with the plastic sheath removed. Consider this as a cylindrical capacitor: imagine there is a linea ...
... insulator, and a cylindrical outer conductor (“copper sheath”), all coaxial with each other. For protection, the cable also has a plastic sheath. Figure (B) shows a piece of this cable of length L and with the plastic sheath removed. Consider this as a cylindrical capacitor: imagine there is a linea ...
Distance - Fixed Earth
... certainly, no Biblical God offering a plan for eternal life to mankind. The Copernican Revolution not only declared the Bible wrong (and also the Koran3), and not only made the Earth and Mankind insignificant accidents in a universe full of star/suns with fantasized planets and evolving life forms, ...
... certainly, no Biblical God offering a plan for eternal life to mankind. The Copernican Revolution not only declared the Bible wrong (and also the Koran3), and not only made the Earth and Mankind insignificant accidents in a universe full of star/suns with fantasized planets and evolving life forms, ...
Investigate Planets, Stars, Galaxies, and the Universe
... the Milky Way Galaxy, the Virgo Supercluster, and the observable universe (the school’s “long address”). This will give students a sense of their place in space. Next, have them watch a video called “The Known Universe” (youtube.com/watch?v=17jymDn0W6U). Developed by the Museum, it zooms out from th ...
... the Milky Way Galaxy, the Virgo Supercluster, and the observable universe (the school’s “long address”). This will give students a sense of their place in space. Next, have them watch a video called “The Known Universe” (youtube.com/watch?v=17jymDn0W6U). Developed by the Museum, it zooms out from th ...
Advancing Physics A2
... The time dilation factor γ is very close to 1 for v substantially less than c but increases rapidly as v approaches c. We start with a discussion of what is involved in ‘thinking relatively’. In Question 50C Comprehension ‘Thinking relatively’ you have to learn to describe events seen from different ...
... The time dilation factor γ is very close to 1 for v substantially less than c but increases rapidly as v approaches c. We start with a discussion of what is involved in ‘thinking relatively’. In Question 50C Comprehension ‘Thinking relatively’ you have to learn to describe events seen from different ...
AST1100 Lecture Notes
... about one part in 1000 of the total mass of the solar system. If this is the normal ratio, and we have no reason to believe otherwise, then the planets can only explain a tiny part of the invisible matter. Brown dwarf stars (more about these in later lectures) are stars which had too little mass to ...
... about one part in 1000 of the total mass of the solar system. If this is the normal ratio, and we have no reason to believe otherwise, then the planets can only explain a tiny part of the invisible matter. Brown dwarf stars (more about these in later lectures) are stars which had too little mass to ...
22. Dark Matter and the Fate of the Universe
... • We infer the existence of dark matter from its gravitational effects on visible matter. The evidence for its existence is overwhelming — if we correctly understand the theory of gravity. Although the success of our theory of gravity in so many other cases makes it unlikely that we could be misinte ...
... • We infer the existence of dark matter from its gravitational effects on visible matter. The evidence for its existence is overwhelming — if we correctly understand the theory of gravity. Although the success of our theory of gravity in so many other cases makes it unlikely that we could be misinte ...
The Scales of Things
... Cepheids are brightest when they are hottest, close to the minimum size. Since all Cepheids are about the same temperature, the size of a Cepheid determines its luminosity. Thus there is a period-brightness relationship for Cepheids. Since it is easy to measure the period of a variable star and t ...
... Cepheids are brightest when they are hottest, close to the minimum size. Since all Cepheids are about the same temperature, the size of a Cepheid determines its luminosity. Thus there is a period-brightness relationship for Cepheids. Since it is easy to measure the period of a variable star and t ...
Week 11 notes
... regions” marking areas of intense star formation activity. HII regions tend to lie along spiral arms. • Radiation from hot, young stars causes the gas to be ionized. The cascade of electrons down atomic energy levels results in an emission line spectrum. Examples of emission lines in the ultraviolet ...
... regions” marking areas of intense star formation activity. HII regions tend to lie along spiral arms. • Radiation from hot, young stars causes the gas to be ionized. The cascade of electrons down atomic energy levels results in an emission line spectrum. Examples of emission lines in the ultraviolet ...
powerpoint - Physics @ IUPUI
... the universe therefore the sizes and distributions tell you something about the distribution of dark matter when the universe formed! • Also, since the curvature of the universe (aka the cosmological constant) changes the shapes of voids as we see them, we can gain some understanding of what the cur ...
... the universe therefore the sizes and distributions tell you something about the distribution of dark matter when the universe formed! • Also, since the curvature of the universe (aka the cosmological constant) changes the shapes of voids as we see them, we can gain some understanding of what the cur ...
Elasticity and Fluid Physics
... The specific gravity of a substance is related to its density. Specific gravity equals the mass of a given volume of the substance divided by the mass of an equal volume of water. To determine the specific gravity of a substance, divide the density of the substance by the density of water at either ...
... The specific gravity of a substance is related to its density. Specific gravity equals the mass of a given volume of the substance divided by the mass of an equal volume of water. To determine the specific gravity of a substance, divide the density of the substance by the density of water at either ...
Cosmology Notes - University of Florida Astronomy
... everywhere else in the Universe. Otherwise the assumption of homogeneity would be violated. Reassuringly, modern observations appear to validate this assumption, at least within the observable universe, with the properties of distant astrophysical objects being consistent with those observed locally ...
... everywhere else in the Universe. Otherwise the assumption of homogeneity would be violated. Reassuringly, modern observations appear to validate this assumption, at least within the observable universe, with the properties of distant astrophysical objects being consistent with those observed locally ...
2008oct23
... • Answer: a) m1a = T + m1g(sinq – m1cosq), m2a = -T + m2g(sinq – m2cosq) b) a = g[sinq – cosq(m1m1+m2m2)/(m1+m2)], T = gcosq(m1-m2)m1m2/(m1+m2) c) m1 > m2 ...
... • Answer: a) m1a = T + m1g(sinq – m1cosq), m2a = -T + m2g(sinq – m2cosq) b) a = g[sinq – cosq(m1m1+m2m2)/(m1+m2)], T = gcosq(m1-m2)m1m2/(m1+m2) c) m1 > m2 ...
Why Our Universe is Comprehensible
... To better understand the requirements for IGUSes let’s think a little outside our model box and consider IGUSes in the expanding universe, modeled by letting the box of Section II expand. The evidence of the observations is that our universe expanded from a hot big bang. In a simplified discussion w ...
... To better understand the requirements for IGUSes let’s think a little outside our model box and consider IGUSes in the expanding universe, modeled by letting the box of Section II expand. The evidence of the observations is that our universe expanded from a hot big bang. In a simplified discussion w ...
Dark Matter in the Universe
... be seen. In other words, most of the universe’s matter does not radiate—it provides no glow that we can detect in the electromagnetic spectrum. First posited some 60 years ago by astronomer Fritz Zwicky, this so-called missing matter was believed to reside within clusters of galaxies. Nowadays we pr ...
... be seen. In other words, most of the universe’s matter does not radiate—it provides no glow that we can detect in the electromagnetic spectrum. First posited some 60 years ago by astronomer Fritz Zwicky, this so-called missing matter was believed to reside within clusters of galaxies. Nowadays we pr ...
Phase Transitions in Early Universe
... understanding on the correlation of various phenomena with so distinctive dimensional scales. Firstly,one problem physicists and cosmologists should be confronted with is the incredibly uniform cosmic radiation background. When radio antennas are pointed at different directions to measure the temper ...
... understanding on the correlation of various phenomena with so distinctive dimensional scales. Firstly,one problem physicists and cosmologists should be confronted with is the incredibly uniform cosmic radiation background. When radio antennas are pointed at different directions to measure the temper ...
Flatness problem
The flatness problem (also known as the oldness problem) is a cosmological fine-tuning problem within the Big Bang model of the universe. Such problems arise from the observation that some of the initial conditions of the universe appear to be fine-tuned to very 'special' values, and that a small deviation from these values would have had massive effects on the nature of the universe at the current time.In the case of the flatness problem, the parameter which appears fine-tuned is the density of matter and energy in the universe. This value affects the curvature of space-time, with a very specific critical value being required for a flat universe. The current density of the universe is observed to be very close to this critical value. Since the total density departs rapidly from the critical value over cosmic time, the early universe must have had a density even closer to the critical density, departing from it by one part in 1062 or less. This leads cosmologists to question how the initial density came to be so closely fine-tuned to this 'special' value.The problem was first mentioned by Robert Dicke in 1969. The most commonly accepted solution among cosmologists is cosmic inflation, the idea that the universe went through a brief period of extremely rapid expansion in the first fraction of a second after the Big Bang; along with the monopole problem and the horizon problem, the flatness problem is one of the three primary motivations for inflationary theory.