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Quasars and Active Galaxies
Quasars and Active Galaxies

... Competing Cosmologies • “Big Bang”: 10 - 20 billion years ago the universe was much more dense than today (and therefore hot and unpleasant). • “Steady State”: As galaxies move apart from each other, new atoms are spontaneously created in empty space. These atoms coalesce to form new galaxies. The ...
Lecture 28 Formation of chemical elements
Lecture 28 Formation of chemical elements

... elements heavier than He. We must look beyond our solar system for the birth of the elements that comprise it. Before we can understand the processes that make the chemical elements, we should look at the processes that formed matter itself. GG325 L28, F2013 ...
Dark Matter in the Universe:
Dark Matter in the Universe:

... Matter in stars & gas (galaxies) < 1% ! Ordinary (baryonic) matter 5% →most of the ordinary matter is “dark” ...
Gilbert Ch 2 - Santa Rosa Junior College
Gilbert Ch 2 - Santa Rosa Junior College

... • Unit used to express the relative masses of atoms and subatomic particles • Equal to 1/12 of a carbon atom: ...
The Universe - Cloudfront.net
The Universe - Cloudfront.net

... Open Universe a model of the universe in which the universe expands forever ...
Questions - Clever Teach
Questions - Clever Teach

... *(b) Scientists believe that the Universe is expanding. Describe how careful observation of electromagnetic radiation from distant galaxies as well as from the whole of space gave evidence supporting the Big Bang Theory. ...
P-process nucleosynthesis in detonating white dwarfs in the light of
P-process nucleosynthesis in detonating white dwarfs in the light of

... shock wave is formed which rapidly transforms into a detonation due to the fast and energetic nuclear combustion developed at the rear edge of the shock wave. Soon a ChapmannJouguet self-sustained detonation emerged (see for instance Fig. 4 of GSBW). During its journey the substrate of the detonatio ...
Advanced Burning Stages - Michigan State University
Advanced Burning Stages - Michigan State University

... In general, weak interactions are much slower than strong interactions. Changes in Ye can therefore be calculated from beta decays and electron captures on the NSE abundances for the current, given Ye In many cases weak interactions are so slow that Ye iis roughly fixed. ...
Cosmological Constant
Cosmological Constant

... (made of quarks) Baryons – massive (ex. proton and neutron) composite fermions Mesons – less massive composite bosons Quark combination for: Proton = uud Neutron = udd ...
Talk - ECT
Talk - ECT

... chiral nuclear forces as well. 3NF should be better understood though. New reaction theories based on these new developments should now be worked on.  Light hadron scattering can be used at low momentum transfers to probe fundamental properties of nuclei such as density distributions, compressibili ...
available for
available for

... One mole of 12C has NA atoms = 6.022 x 1023 atoms 0.012 Kg = NA x 12 u ® 1 u = 0.012/(NA x 12) = 1.66 x 10-27 Kg Using E=mc2 then, Energy equivalent = 1.66 x 10-27 x (2.99 x 108)2 = 1.48 x 10-10 J Divide by electron charge to convert to eV = 931.502 MeV Then 1 u = 931.502 MeV/c2 or c2 = 931.502 MeV/ ...
Cosmology
Cosmology

... light years). – For more distant objects the light has not had time to reach us. – Edge of universe (from our perspective) is the cosmic light horizon ...
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... Rolfs & Rodney: Cauldrons in the Cosmos, 1988 ...
1 Origin of the Elements. Isotopes and Atomic Weights
1 Origin of the Elements. Isotopes and Atomic Weights

... nuclei (p C n), then helium (2p C 2n). The process of element building had begun. During this small niche of cosmic history, from about 10 500 s after the big bang, the entire universe is thought to have behaved as a colossal homogeneous fusion reactor converting hydrogen into helium. Previously no ...
SUMMARY OF KEY CONCEPTS: GALAXIES AND COSMOLOGY
SUMMARY OF KEY CONCEPTS: GALAXIES AND COSMOLOGY

... galaxy, we define the redshift z via z = (lobserved-lrest)/lrest. Distant galaxies have large redshifts. For small redshifts, the redshift can be related to the recession velocity via a simple formula v = cz, where c is the speed of light. Lecture #19 We discussed Olber’s Paradox - `why is the night ...
The Magic of Star Dust - Exploring Exotic Nuclei
The Magic of Star Dust - Exploring Exotic Nuclei

... ur universe is made up of planets, galaxies, and stars. Seeking the clues to the origin of our existence, we look back at how the creation and evolution of the universe occurred. Our present understanding is the universe started with a big bang that created a soup of objects, among which were the ma ...
Revision Guide (Unit 2 Module 5) - Pearson Schools and FE Colleges
Revision Guide (Unit 2 Module 5) - Pearson Schools and FE Colleges

... Measurements suggest that the density of the universe is close to this critical value. Many theoreticians think that it may well be exactly equal to this value – that, unlikely as it seems, we live in a universe with a ‘flat’ cosmology. ...
Ivelina Sotirova Major: Biochemistry Senior at CUNY Hunter College
Ivelina Sotirova Major: Biochemistry Senior at CUNY Hunter College

... Supernova Search Team (HZT) led by Brian Schmidt and Adam Riess defied the very status quo of cosmology when they discovered independently, but concurrently, that, instead of slowing down, distant galaxies are accelerating further and further away from us. The evolution of our Universe began 14 bill ...
Lecture 2
Lecture 2

... -  When the star dies, they are expelled into space…. to form new stars and planets. Most of the atoms in our bodies were created in the core of a star! ...
Slide 1
Slide 1

... constant has been revived as a simple explanation for dark energy. Other problems with the model Aside from Hubble's law, the cosmic microwave background radiation is used as empirical evidence of the Big Bang model. A static universe model has to explain this radiation in some other way. Also there ...
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... Often, some, but not all nuclei are in equilibrium with protons and neutrons (and with each other). A group of nuclei in equilibrium is called an equilibrium cluster. Because of reactions involving single nucleons or alpha particles being the mediators of the equilibrium, neighboring nuclei tend to ...
Stars and Galaxies
Stars and Galaxies

... This model states that the universe formed and then it expanded, or grew larger. Over time, the rate of growth slowed down. Then the universe began to contract, or shrink. Then the whole process began again. In other words, it oscillates back and forth in size. A third model is called the big bang t ...
Next…. Both our past and our future depend on amount of matter in
Next…. Both our past and our future depend on amount of matter in

... gravity and causes the expansion of the universe to accelerate. C.  Any unknown force that acts like gravity D.  Highly energetic particles that are believed to constitute dark matter E.  The total energy in the universe after the Big Bang but before the first stars ...
Recollapsing Universe
Recollapsing Universe

... solutions, told Hubble (observing redshifts since 1924) that cosmic expansion suggests more distant galaxies should have greater redshifts (Hubble publishes V = Hod in 1929) •  Einstein visited Hubble in 1932, said CC was “the greatest blunder” of his career ...
DTU_9e_ch18 - University of San Diego Home Pages
DTU_9e_ch18 - University of San Diego Home Pages

... According to the theory of inflation, early in its existence, the universe expanded very rapidly for a short period, spreading matter that was originally far from our location (and hence at different temperatures and densities) throughout a volume of the universe so large that we cannot yet observe ...
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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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