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Using Galaxy Clusters to Study Structure Evolution
Using Galaxy Clusters to Study Structure Evolution

... universe is expanding homogeneously and is not static. »The universe was denser in the past »The universe had a beginning….? ...
Here
Here

... protons) combine to form 1 helium nucleus (which has two protons and two neutrons). • The details are a bit complex:  In the Sun, 6 hydrogen nuclei are involved in a sequence that produces two hydrogen nuclei and one helium nucleus. This is the proton-proton chain.  In more massive stars, a carbon ...
powerpoint  file
powerpoint file

... Everything started out 13.7 billion years ago with “zero” size and “infinite” temperature. Since then, it has been expanding and cooling. Now its temperature is 2.735 K. While the temperature was still high enough — at age 2 to 30 minutes — protons and neutrons fused to form a light elements. As a r ...
Readings for Prof. Michael J. Crowe`s Two Sessions on The
Readings for Prof. Michael J. Crowe`s Two Sessions on The

... the matter and energy in the universe. What triggered this sudden expansion remains a mystery. Astronomers believe it involved a runaway process called ‘inflation,’ in which a peculiar type of energy that existed in the vacuum of space was suddenly mobilized. The inflationary expansion ended only wh ...
The Universe - Cloudfront.net
The Universe - Cloudfront.net

... Concept Check What relationship did Hubble discover between red shifts and the distances of galaxies from Earth?  Galaxies that have the greatest red shifts are the most distant. ...
PART II: Life of a Star
PART II: Life of a Star

... At about t_universe = 1 minute the temperature was too high for any subatomic particles to form. The Universe was cooling due to the expansion and eventually reached a critical point (~109 K, 0.1 MeV), below the binding energies of the light nuclei. Thus the first nuclei were formed at this time. Fu ...
protostars and pre-main
protostars and pre-main

... Final ingredient: Mass accretion rate, from collapse model. Equations are solved € using guessed central values for P, T, iterate until match with outer boundary conditions. ...
Realized in String Theory - Department of Physics & Astronomy
Realized in String Theory - Department of Physics & Astronomy

... finite system of axioms to prove every result in mathematics. This means that inconsistencies or indeterminacies can arise if one tries to prove statements that refer to themselves. A physical theory is a mathematical model. So if there are mathematical results that cannot be proved, there are physi ...
PowerPoint Presentation - Inflation, String Theory
PowerPoint Presentation - Inflation, String Theory

... This process continues, and eventually the universe becomes populated by inhomogeneous scalar field. Its energy takes different values in different parts of the universe. These inhomogeneities are responsible for the formation of galaxies. Sometimes these fluctuations are so large that they substant ...
Seating Chart for Final Exam PHOTO ID REQUIRED! SIT IN YOUR ASSIGNED ROW!
Seating Chart for Final Exam PHOTO ID REQUIRED! SIT IN YOUR ASSIGNED ROW!

... Bottom-right plot : shows matter is distributed on the surfaces of giant bubbles. But I also described smaller structures (galaxy clusters, etc). Slide 5: The figures are for an analogy of a bug living on a rubber-sheet universe which is a 2D surface curved into a 3rd spatial dimension. We live in 3 ...
protostars and pre-main-sequence evolution.key
protostars and pre-main-sequence evolution.key

... Final ingredient: Mass accretion rate, from collapse model. Equations are solved € using guessed central values for P, T, iterate until match with outer boundary conditions. ...
Cosmology Notes - U of L Class Index
Cosmology Notes - U of L Class Index

... in the early stages of the big bang (as Hoyle, Fowler and Wagoner showed), and there is no credible model of how such large stars could arise in the steady state model. Cosmic background radiation: Gamow had shown in the 1940’s that the big bang would have left behind a “glow” in the form of a low- ...
Cosmology Question Answer 1. What are the essenti
Cosmology Question Answer 1. What are the essenti

... general theory of relativity. The detection of the cosmic backgound radiation in 1965 offered unequivocal support for the Big Bang model of the origin of the universe implied by relativity. The discovery of minute variations in the cosmic background radiation in 1992 and 2002 offered strong support ...
Ratio - Boys v Girls..
Ratio - Boys v Girls..

... ...
absolute past
absolute past

... • Einstein discovered that light has a speed, and it is invariable. It takes time for light to travel. A thousand kilometers takes around 0.0033356 second, and a million kilometers 3.3356 seconds. In other words, light travels at a speed of approximately 300,000 kilometers per second. • Since light ...
Problems with the Perfect Circles
Problems with the Perfect Circles

... • Einstein discovered that light has a speed, and it is invariable. It takes time for light to travel. A thousand kilometers takes around 0.0033356 second, and a million kilometers 3.3356 seconds. In other words, light travels at a speed of approximately 300,000 kilometers per second. • Since light ...
Physics in the Balance - Max-Planck
Physics in the Balance - Max-Planck

... this balance would be the detection method of choice for new elements. The current standard method can detect only ions that quickly decay again. It has been used for decades at all particle accelerators that produce heavy elements. Their detectors react only to the decay products, from whose data t ...
How physicists study the structure of matter
How physicists study the structure of matter

... to the airport and asking the security guards there to use their X-ray machine to examine your gift. That’s a good idea. However, all you find out is that there is a smaller box inside, made of thick plates of lead. You still cannot see what’s inside the smaller box even with the X-rays. So, what sh ...
The lifes of a star
The lifes of a star

... a percent of the total solar mass). The jargon is that this reaction “burns” Hydrogen and that resulting “ashes” are mainly Helium. The above is just one of a very large number of fusion reactions but it is the most common, and is present in all stars at some stage of their lifes. Other reactions ar ...
P1a_Revision_lesson
P1a_Revision_lesson

... support the Big Bang Theory – this explanation is based around the rates of expansion and contraction of different galaxies. If our neighbouring galaxy is expanding at a different rate to the Milky Way then it will appear red or blue-shifted. ...
(convective) core of a star
(convective) core of a star

... 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 ...
Here
Here

... protons) combine to form 1 helium nucleus (which has two protons and two neutrons). • The details are a bit complex:  In the Sun, 6 hydrogen nuclei are involved in a sequence that produces two hydrogen nuclei and one helium nucleus. This is the proton-proton chain.  In more massive stars, a carbon ...
30.4 Gravitational collapse & early protostellar evolution I (HB)
30.4 Gravitational collapse & early protostellar evolution I (HB)

... temperature stays approximately constant. Since L = 4πR2sBTeff4 R*2, the luminosity decreases and falls below Lcrit. --> Radiative core forms again leaving a shrinking outer convective layer. In this radiative phase, during further slow contraction internal energy, temperature and luminosity rise ...
Today`s physics - University of Washington
Today`s physics - University of Washington

... be calculated, and it is huge: billions and billions. Nature uses these combinations, called molecules, to build planets, suns, viruses, mountains, paychecks, Valium, literary agents, and other useful items. It was not always so. During the earliest moments after the creation of the universe in the ...
Big bang, red shift and doppler effect
Big bang, red shift and doppler effect

... The diagram shows a teacher using a loudspeaker to demonstrate an important effect. The loudspeaker, which produces a note of constant frequency, is swung around in a circle. ...
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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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