Teacher`s Guide Understanding: The Universe
... 1. Discuss why some scientists were uneasy about the idea of an expanding universe. 2. Astronomer Wendy Freedman's observations of Cepheid variable stars in another galaxy indicated that the age of the universe is about eight to twelve billion years. Why did her discovery cause such a debate among a ...
... 1. Discuss why some scientists were uneasy about the idea of an expanding universe. 2. Astronomer Wendy Freedman's observations of Cepheid variable stars in another galaxy indicated that the age of the universe is about eight to twelve billion years. Why did her discovery cause such a debate among a ...
Chapter105.ppt
... • Planets are made from planetesimals; originally the rings of gas and dusk surrounding a protostar. The Moon formed when another celestial body collided with the Earth to create a massive cloud of dust and debris that coalesced to form the Moon. ...
... • Planets are made from planetesimals; originally the rings of gas and dusk surrounding a protostar. The Moon formed when another celestial body collided with the Earth to create a massive cloud of dust and debris that coalesced to form the Moon. ...
George`s slides
... • If there is a Theory of Everything (TOE) that unifies all four forces it will break spontaneously at the Planck 5me (t ~10-43 sec) into the gravita5on and a unified version of the magne5c, electroweak, and strong forces – a Grand Unified Theory (GUT) • The GUT will hold un5l T ~1028 K, or t ~ 1 ...
... • If there is a Theory of Everything (TOE) that unifies all four forces it will break spontaneously at the Planck 5me (t ~10-43 sec) into the gravita5on and a unified version of the magne5c, electroweak, and strong forces – a Grand Unified Theory (GUT) • The GUT will hold un5l T ~1028 K, or t ~ 1 ...
04 Astrophysics_-_lesson_4 cosmology
... very little light to an observer on Earth but there are many of them. So if there is an infinite number of stars, each one emitting a certain amount of light, the total energy received must be infinite, making the night sky infinitely bright, which is not. ...
... very little light to an observer on Earth but there are many of them. So if there is an infinite number of stars, each one emitting a certain amount of light, the total energy received must be infinite, making the night sky infinitely bright, which is not. ...
moderncos
... Curvature can be determined through analysis of the ripples in the CMB Position gives: k = 0 (Flat!) ...
... Curvature can be determined through analysis of the ripples in the CMB Position gives: k = 0 (Flat!) ...
Time From the Perspective of a Particle Physicist
... • It has been observed (first by Hubble in the 1920’s) that galaxies are moving away from us and that the further away they are the faster they are moving (v=Hd) • Indication that the Universe is expanding, and it has been ever since it was created in the Big Bang about 13 billion years ago • Unders ...
... • It has been observed (first by Hubble in the 1920’s) that galaxies are moving away from us and that the further away they are the faster they are moving (v=Hd) • Indication that the Universe is expanding, and it has been ever since it was created in the Big Bang about 13 billion years ago • Unders ...
BBN + Inflation
... Inflation in GUT • In Grand Unified Theories (GUT) there was an quantum mechanical field that caused inflation at 10-35 s and lasted for ~100 e-foldings. • Starting with a strongly curved universe, this would drive the flatness to e-2100 ~ 10-87. • If inflation ended at 10-33 s, then size of curre ...
... Inflation in GUT • In Grand Unified Theories (GUT) there was an quantum mechanical field that caused inflation at 10-35 s and lasted for ~100 e-foldings. • Starting with a strongly curved universe, this would drive the flatness to e-2100 ~ 10-87. • If inflation ended at 10-33 s, then size of curre ...
Physics116_L42
... "[George Gamow] casually mentioned that...according to Einstein's equations, a star could be created out of nothing at all, because its negative gravitational [binding] energy precisely cancels out its positive mass energy. "Einstein stopped in his tracks," says Gamow, "and, since we were crossing a ...
... "[George Gamow] casually mentioned that...according to Einstein's equations, a star could be created out of nothing at all, because its negative gravitational [binding] energy precisely cancels out its positive mass energy. "Einstein stopped in his tracks," says Gamow, "and, since we were crossing a ...
PARTS OF THE UNIVERSE
... ORIGINS OF THE UNIVERSE v Big Bang Theory: states that all matter and energy were once packed into a tiny particle smaller than a speck of dust. v The particle began to expand and matter and energy moved rapidly outward in all directions. v The matter cooled and collected to form stars, galax ...
... ORIGINS OF THE UNIVERSE v Big Bang Theory: states that all matter and energy were once packed into a tiny particle smaller than a speck of dust. v The particle began to expand and matter and energy moved rapidly outward in all directions. v The matter cooled and collected to form stars, galax ...
Lecture 3 Geocentrism vs.Heliocentrism
... Planets on physical spheres – each moving the other – earth and sphere of prime mover stationary ...
... Planets on physical spheres – each moving the other – earth and sphere of prime mover stationary ...
Chapter 2 Basic Chemistry
... – Get their energy from nuclear fusion • Combines the nuclei of hydrogen atoms into helium • When hydrogen nuclei collide, they fuse to form new nuclei called deuterons (one proton and one neutron) • Another proton collides with deuteron to form a helium isotope, helium-3 • Next, two mhelium-3 isoto ...
... – Get their energy from nuclear fusion • Combines the nuclei of hydrogen atoms into helium • When hydrogen nuclei collide, they fuse to form new nuclei called deuterons (one proton and one neutron) • Another proton collides with deuteron to form a helium isotope, helium-3 • Next, two mhelium-3 isoto ...
Word - Sam Davyson
... This assumes that the speed is constant for a galaxy. Due to gravity it isn’t which gives an over-estimate on the age of the universe. H0 is not precisely known. Using different ways of measuring distances (eg. Type II Supernovae vs. Rotation of galaxies etc. ) different values for H0 are found. ...
... This assumes that the speed is constant for a galaxy. Due to gravity it isn’t which gives an over-estimate on the age of the universe. H0 is not precisely known. Using different ways of measuring distances (eg. Type II Supernovae vs. Rotation of galaxies etc. ) different values for H0 are found. ...
Theories
... Bang is still considered by most astronomers to be the best theory we have. As with any scientific hypothesis, however, more observation and experimentation are needed to determine its credibility. ...
... Bang is still considered by most astronomers to be the best theory we have. As with any scientific hypothesis, however, more observation and experimentation are needed to determine its credibility. ...
Local Group Dwarfs
... – Planck length, time = QED – Compton length, time = QED – Schwarzschild length, time = gravity The way these are related defines who is in charge – gravity or QED Funny feature: a Planck mass into the formula for Compton, Schwarzschild lengths = Planck length Also, all times are equal. ...
... – Planck length, time = QED – Compton length, time = QED – Schwarzschild length, time = gravity The way these are related defines who is in charge – gravity or QED Funny feature: a Planck mass into the formula for Compton, Schwarzschild lengths = Planck length Also, all times are equal. ...
Characteristics Of The Universe Origin Of Universe
... space. The shape of space is, surprisingly, curved. On a very large scale—millions or even billions of light-years across— space has a three-dimensional “saddle shape” that mathematicians refer to as “negative curvature.” In our daily lives, however, it is such a tiny effect that we do not notice it ...
... space. The shape of space is, surprisingly, curved. On a very large scale—millions or even billions of light-years across— space has a three-dimensional “saddle shape” that mathematicians refer to as “negative curvature.” In our daily lives, however, it is such a tiny effect that we do not notice it ...
Shape of the universe
The shape of the universe is the local and global geometry of the Universe, in terms of both curvature and topology (though, strictly speaking, the concept goes beyond both). The shape of the universe is related to general relativity which describes how spacetime is curved and bent by mass and energy.There is a distinction between the observable universe and the global universe. The observable universe consists of the part of the universe that can, in principle, be observed due to the finite speed of light and the age of the universe. The observable universe is understood as a sphere around the Earth extending 93 billion light years (8.8 *1026 meters) and would be similar at any observing point (assuming the universe is indeed isotropic, as it appears to be from our vantage point).According to the book Our Mathematical Universe, the shape of the global universe can be explained with three categories: Finite or infinite Flat (no curvature), open (negative curvature) or closed (positive curvature) Connectivity, how the universe is put together, i.e., simply connected space or multiply connected.There are certain logical connections among these properties. For example, a universe with positive curvature is necessarily finite. Although it is usually assumed in the literature that a flat or negatively curved universe is infinite, this need not be the case if the topology is not the trivial one.The exact shape is still a matter of debate in physical cosmology, but experimental data from various, independent sources (WMAP, BOOMERanG and Planck for example) confirm that the observable universe is flat with only a 0.4% margin of error. Theorists have been trying to construct a formal mathematical model of the shape of the universe. In formal terms, this is a 3-manifold model corresponding to the spatial section (in comoving coordinates) of the 4-dimensional space-time of the universe. The model most theorists currently use is the so-called Friedmann–Lemaître–Robertson–Walker (FLRW) model. Arguments have been put forward that the observational data best fit with the conclusion that the shape of the global universe is infinite and flat, but the data are also consistent with other possible shapes, such as the so-called Poincaré dodecahedral space and the Picard horn.