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Notes - Michigan State University
Notes - Michigan State University

... Experimental Nuclear Astrophysics was born ...
ASTR 001 Introduction to the Cosmos
ASTR 001 Introduction to the Cosmos

... 23. Evidence that the cosmic background radiation really is the remnant of a Big Bang comes from predicting characteristics of remnant radiation from the Big Bang and comparing these predictions with observations. Four of the five statements below are real. Which one is fictitious? A) The cosmic ba ...
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Slide 1

... 1) the information about the initial abundance ratio, usually it is taken from the standard cosmology; that is why it is necessary to suppose the validity of this theory; 2) the universality of r-process, more exactly it is the hypothesis that the abundance ratios in the products of different supern ...
age of the universe.
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... In the first few minutes after the Big Bang, a) the universe cooled and formed neutral matter. b) the cosmic microwave background radiation was released. c) electrons recombined with protons. d) hydrogen fused into deuterium and then helium. e) the universe was governed by one unified superforce. Ex ...
CosmologyL2
CosmologyL2

... the expansion is continually slowing down; blue - an open, low density universe, expansion is slowing down, but not as much because the pull of gravity is not as strong. red - a universe with a large fraction of matter in a form of dark energy, causing an accelerated expansion . ...
Origin of the Chemical Elements
Origin of the Chemical Elements

... Chemical elements are central for the existence of life and the richness and variety of our environment. Therefore, one of the basic questions concerns the origin of the chemical elements. The answer is complex because it relies on dynamical processes from elementary particles and nuclei to stars an ...
PPT
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 ...
The Early Universe
The Early Universe

... maximum distance we can see out to in the Universe. More generally, for any point in the Universe, the horizon is the maximum distance from which light could have reached that point, within the age of the Universe. Nothing outside your horizon can have any effect on you, because it has never been in ...
Radioactivity and man
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... All matter that surrounds us is made up of atoms. Every atom consists of protons and neutrons, which together form the nucleus, surrounded by a cloud of negatively-charged electrons. Within the atom, the nucleus is made up of positively charged protons and by neutrons that lack electric charge and a ...
Topic 4 - The University of Sheffield
Topic 4 - The University of Sheffield

... (1)!A MACHO Event should never repeat (they are too rare). (2)!The Light Curve for a MACHO should be symmetric in ! time, i.e. rising and falling with the same shape. (3)!The magnitude of the Light Amplification should be the ! ! same in all wavelengths e.g. the blue and red wavebands ! as typically ...
Chapter 31 - The Galaxy & Universe
Chapter 31 - The Galaxy & Universe

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No Slide Title

... Hubble telescope was used to observe 19 galaxies out to 108 million lightyears. They discovered almost 800 Cepheid variable stars, a special class of pulsating star used for accurate distance measurements. Here is a picture of one of those galaxies. It is the spiral galaxy NGC 4603, the most distant ...
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... the universe were indeed expanding, and has been doing so for its entire existence, then there would have to be a moment in the distant past when the whole universe occupied just a single point. That moment, and that point, would be the origin of the cosmos. Lemaître’s work, and that of de Sitter an ...
Course 107: The Big Bang and the Anthropic Principle
Course 107: The Big Bang and the Anthropic Principle

... ○ Many things in the universe may either exist or not exist, and are all finite. ○ Such things are called __ beings. (not infinite; not eternal) ○ It is impossible for everything in the universe to be contingent, for then there would be a time when __ existed, and therefore, nothing would exist now ...
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... on the evolution of mass and radius instead of the temperature and luminosity. One reason is that much of the luminosity of the star is accretion luminosity, and not emission from a stellar photosphere as in a normal star. Another reason is that accreting layers of gas may absorb the stellar radiati ...
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... the Universe expanded (and cooled) from this initial infinitesimally small size which encompassed all of space, energy, matter and radiation, it remained opaque and inscrutable for the first 380 000 years, when photons and electrons were so strongly coupled together that light could not travel very ...
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... dark matter even if we don’t know anything about the particles it consists of. But this conclusion should be ok as long as the known laws of physics applies to them. Until ten years ago it was generally believed that the universe contained only radiation and matter. But since then it has become cle ...
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... 5) Watch Minute Physics: The Oldest Light in the Universe http://www.youtube.com/watch?NR=1&feature=endscreen&v=_mZQ-5-KYHw What is the cosmic background radiation and what does it have to do with the big bang? Student Answer: The universe used to be very hot and emitting light for that temperature. ...
The Teleological Argument - University of Colorado Boulder
The Teleological Argument - University of Colorado Boulder

... He goes on to say that, even if the chain of watches extended infinitely back into the past, so that there have ALWAYS been watches making watches, this would not rid us of the need for a designer. If one watch requires a designer, and so do two watches, and one hundred, and one million watches, why ...
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... Bang the energy of neutrinos was so low that such processes could no longer occur and their number density was fixed to this day. This number is very similar to the one of the photons in the observed Cosmic Microwave Background Radiation, the so-called ‘afterglow’ of the Big Bang, making neutrinos t ...
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The Designed `Just So` Universe Dr. Walter L. Bradley Walter L

... for multiple reasons. Note from Table 2 that the electromagnetic force is 1038 times stronger than the gravity force. It is the force of gravity that draws protons together in stars causing them to fuse together with a concurrent release of energy. The electromagnetic force causes them to repel. Bec ...
"Cosmic furnaces"()
"Cosmic furnaces"()

... from ancient times, it has often been worshipped. More recently, we have come to understand that not only do we rely on our local star to sustain us, but that we actually exist because of other, long dead, stars. The Earth, and almost everything on it, is made from the ashes of giant stars that live ...
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Big Bang nucleosynthesis

In physical cosmology, Big Bang nucleosynthesis (abbreviated BBN, also known as primordial nucleosynthesis) refers to the production of nuclei other than those of the lightest isotope of hydrogen (hydrogen-1, 1H, having a single proton as a nucleus) during the early phases of the universe. Primordial nucleosynthesis is believed by most cosmologists to have taken place from 10 seconds to 20 minutes after the Big Bang, and is calculated to be responsible for the formation of most of the universe's helium as the isotope helium-4 (4He), along with small amounts of the hydrogen isotope deuterium (2H or D), the helium isotope helium-3 (3He), and a very small amount of the lithium isotope lithium-7 (7Li). In addition to these stable nuclei, two unstable or radioactive isotopes were also produced: the heavy hydrogen isotope tritium (3H or T); and the beryllium isotope beryllium-7 (7Be); but these unstable isotopes later decayed into 3He and 7Li, as above.Essentially all of the elements that are heavier than lithium and beryllium were created much later, by stellar nucleosynthesis in evolving and exploding stars.
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