Allgemein

Urknall und Kosmologie
Copyright © CERN 1997 -- European Laboratory for Particle Physics, Karl-Heinz Kampert
Eine Präsentation auf Basis anklickbarer webslider, die einen knappen Überblick über den heutigen Stand der Urknalltheorie gibt.
http://www.physik.uni-karlsruhe.de/lehrer00/kampert/index.html

Überblick Kosmologie
Peter Schneider

http://www.astro.uni-bonn.de/~peter/cosmo_short.html

Cosmos in a Computer
expo@ncsa.uiuc.edu
Witness the birth of the cosmos, watch the universe unfold, all from your desktop. Sounds ambitious, but cosmologists are doing just that: developing powerful computer models that "evolve" the universe from the Big Bang to the present.

http://www.ncsa.uiuc.edu/Cyberia/Expo/cosmos_nav.html

Kernsynthese im frühen Universum
Jan B. Rehm

Heliumentstehung im Urknall

Nach dem heutigen Stand der Kosmologie hat das Universum seinen Ursprung vor etwa 10-15 Milliarden Jahren in einem unendlich dichten und heißen Feuerball, dem Urknall. Es gibt allerdings bisher keine physikalische Theorie, die in dieser frühesten Entwicklungsphase des Kosmos gültig ist. Mit unserem heutigen Wissen können wir die Entwicklung des Universums erst ab etwa 10^{- 43} Sekunden (ausgeschrieben wäre das eine 1 an der 43. Stelle nach dem Komma!) nach dem Urknall beschreiben, wobei allerdings noch viele Fragen offen sind.

Zu diesem frühen Zeitpunkt besteht das Universum aus einer Ursuppe von Elementarteilchen. Die Temperatur dieser Ursuppe beträgt 10³² Kelvin (Eine 1 mit 32 Nullen). Zum Vergleich: Die Sonnenoberfläche hat etwa 6000 Kelvin, im Zentrum der Sonne herrschen Temperaturen von 10 Millionen Kelvin. (Die Kelvin-Temperaturskala ist um 273 gegenüber der Celsius-Temperaturskala verschoben: 0 Kelvin entsprechen -273° Celsius)

Im Laufe seiner Entwicklung expandierte das Universum bis zu seiner heutigen Größe, dabei bildeten sich die Galaxien, Sterne und Planeten, die wir heute beobachten.

Während dieses Expansionsprozesses kühlte sich das Universum immer weiter ab. Die kosmische Hintergrundstrahlung, die ihren Ursprung im Urknall hat und an der gesamten thermischen Entwicklung des Universums teilgenommen hat, hat heute eine Temperatur von etwa 3 Kelvin (-270 Celsius)

In der ersten Minuten der Existenz des Universums, während der frühesten Abkühlungsphase, fanden Kernreaktionen statt, in denen das Helium gebildet wurde. Dies wird von der Theorie der Primordialen Nukleosynthese beschrieben.

http://www.mpa-garching.mpg.de/~jan/papers/OpenDay/OpenDayhtml.html

http://www.c-online.de/planckwelt/

Ned Wright's Cosmology Tutorial
Edward L. Wright - wright@astro.ucla.edu
Cosmology is the study of the origin, current state, and future of our Universe. This field has been revolutionized by many discoveries made during the past century. My cosmology tutorial is an attempt to summarize these discoveries. It will be "under construction" for the foreseeable future as new discoveries are made. I will attempt to keep these pages up-to-date as a resource for the cosmology courses I teach at UCLA.

Astronomy and cosmology are very much mathematical sciences, but I have attempted to avoid higher math in these pages. I do use high school algebra and geometry - courses required for admission to UCLA - but I have also included some animations [1, 2, 3, 4], some Java applets [1, 2], and many illustrations in the tutorials, the ABC's of Distances, and the answers to some of the Frequently Asked Questions.

In addition to the cosmology tutorial, there is also a relativity tutorial and extensive discussions on the age, density and size of the Universe. There is also a bibliography of books at a range of levels, and a Javascript calculator of the many distances involved in cosmology.
http://www.astro.ucla.edu/~wright/cosmolog.htm

Cosmology - A Research Briefing
National Academy of Sciences

http://www.nap.edu/readingroom/books/cosmology/

A brief history of cosmology
David Wands
Four thousand years ago the Babylonians were skilled astronomers who were able to predict the apparent motions of the moon and the stars and the planets and the Sun upon the sky, and could even predict eclipses. But it was the Ancient Greeks who were the first to build a cosmological model within which to interpret these motions...

Since the early 1980's there has been an explosion of interest in the physics of the early universe. New technology and satellite experiments, such as the Hubble Space Telescope, have brought us an ever improving picture of our Universe, inspiring theorists to produce ever more daring models, drawing upon the latest ideas in relativity and particle physics.
http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Cosmology.html

Cosmology and Theoretical Physics
umeetsng@intouch.bc.ca
These pages deal mainly with the Mathematical aspects of Cosmology,Black Holes and Space time.
http://members.tripod.com/~albert51/index.html

John Gowan's General Systems HomePage
John A. Gowan - jag8@cornell.edu
Gravity is matter's memory that it once was light
Gravity is the conserved form of light's intrinsic motion as expressed in matter. The conservation role of gravity is to create matter's time dimension by converting space into time. Time (spacetime) is the dimensional conservation domain of matter, and gravity is matter's expression of entropy. Hence we see that entropy, whether positive or negative, functions to create a dimensional conservation domain in which both action and energy conservation can occur. This is the intimate relationship between the first and second laws of thermodynamics, and the conservation role of both the intrinsic motion of free energy and the gravitational field of bound energy.

1) Light's intrinsic motion (= light's positive entropy) produces space and the expansion and cooling of space. Gravity is the conserved form of light's entropy and intrinsic motion; gravity is matter's negative entropic force, causing the contraction and heating of space. Gravity's conservation role is the production of matter's time dimension through the consumption of space; in turn, the one-way motion of time induces the continuous, one-way flow of gravitation. Time produces a third type of entropy, creating the information realm.
2) The charges of matter are symmetry debts of light.
3) The function of charge is to allow the conversion of light to matter, and matter to light. Insofar as charge is equivalent to information, this is also the function of information.
4) Space is the conservation domain of light; spacetime is the conservation domain of matter; charge is the conservation domain of symmetry; life is the conservation domain of information.

http://www.people.cornell.edu/pages/jag8/

DISTANT GALAXIES AND COSMOLOGICAL MODELS
Edward J. Barlow - edbarlow@aol.com
Astronomers observe distant galaxies, quasars and supernovae. They can measure apparent luminosity and redshift. From these measurements they seek to deduce things like velocity of recession expressed by the Hubble constant, distance away the galaxy or object is, age of the universe when the light was emitted they are now observing, present age of the universe and its future development, the value of the cosmological constant (lambda), the presence of dark matter, the shape of space and the like. To make these deductions, mathematical models called cosmological models are used. There have been many such models used over the years. Observations are suggesting which models are closest to fitting our real universe. How old is the universe? Is the expansion slowing down or speeding up? What is the eventual fate of the universe? Exciting things are happening and new data are pouring in. In this paper, a series of models of increasing sophistication is presented and related to experimental data to help with these questions and to help with understanding and interpreting how observations are being reported in the press. The concepts of general relativity used for these models are also described. Many easy-to-understand graphs and equations are also included. The graphs are presented with simple axes like time in years and distances in light-years.
http://www.cosmologymodels.com

String theory and Cosmology
There's a lot of compelling evidence for the Big Bang, but what preceded it? The most accepted model is called Inflation. What happens when the early universe is gummed up with string? And are any of these scenarios testable in the near future?
http://www.superstringtheory.com/cosmo_o.html

Relativity and Cosmology
Jose Wudka

Contents From Antiquity to Einstein Introduction Overview The scientific method What is the ``scientific method''? What is the difference between a fact, a theory and a hypothesis? Truth and proof in science. If scientific theories keep changing, where is the Truth? What is Ockham's Razor? How much fraud is there in science? Are scientists wearing blinkers? Why should we worry? Large numbers Times (in seconds) Distances (in meters) Velocities (in meters per second) Masses (in kilograms) Temperatures (in deg. Kelvin) Monies (in 1994 US dollars) Greek cosmology Egypt and Babylon Babylon Egypt Other nations India China Early Greeks Mythology Early cosmology The Pythagoreans Early heliocentric systems Aristotle and Ptolemy Aristotelian Cosmology The motion according to Aristotle Ptolemy From the Middle Ages to Heliocentrism Preamble The Middle Ages. The Copernican Revolution Aristotle in the 16th century Kepler Galileo and Newton Introduction Galileo Galilei Galilean relativity Mechanics The motion of falling bodies The motion of projectiles Astronomy Galileo and the Inquisition Isaac Newton Mechanics. 1st Law and Newtonian space and time. 2nd Law 3rd Law Optics Gravitation. The Clouds Gather Electricity and magnetism Electricity Magnetism Waves vs. particles Light Problems Ether Galilean Relativity Prelude to relativity Einstein's Relativity and Modern Cosmology The Special Theory of Relativity Introduction Enter Einstein The first prediction: the speed of light and the demise of Newton's mechanics The second prediction: Simultaneity is relative The first murder mystery (ca. 1890) The second murder mystery (ca. 2330) The third prediction: The demise of Universal Time Length contraction Paradoxes. Space and Time The top speed. Mass and energy. The General Theory of Relativity The happiest thought of my life. Newton vs. Einstein Gravitation vs acceleration Light Clocks in a gravitational force. Black holes Gravitation and energy Space and time. Properties of space and time. Curvature Waves Summary. Tests of general relativity. Precession of the perihelion of Mercury Gravitational red-shift. Light bending The double pulsar The universe: size, origins, contents Introduction Light revisited The inverse-square law The Doppler effect Emission and absorption lines A happy marriage Cosmic distance ladder Step 1: distances up to 100 l.y. Step 2: distances up to 300,000 l.y. Step 3: distances up to 13,000,000 l.y. Step 4: distances up to 1,000,000,000 l.y. Step 5: distances beyond 1,000,000,000 l.y. The relativistic universe The expanding universe And now what? The Microwave Background Radiation Nucleosynthesis At the cutting edge Dark matter Neutrinos The cosmological constant Homogeneity and isotropy Inflation Summary The lifes of a star Introduction. Stellar Power The lifes of a star In the beginning A rising star A Giant appears And so it goes Light stars Medium-size stars The heavyweights

http://phyun5.ucr.edu/~wudka/Physics7/Notes_www/