this animation begins with a collapsing interstellar cloud of gas and dust. most of the material...
TRANSCRIPT
This animation begins with a collapsing interstellar cloud of gas and dust. Most of
the material becomes part of the young Sun, but some debris forms a disk. Within this disk form the planets, moons, comets,
asteroids, and meteoroids. Note that this process is repeated on a smaller scale in the
outer solar system, where miniature disks form around the Jovian planets.
Within the Orion Nebula—a giant cloud of gas and dust some 1500 light-years from Earth—new stars, and perhaps
new planets, are being formed.
The final closeup is a young star surrounded by a dark disk of material within which planets may be forming.
(HST images).
The Merger of Two Disk GalaxiesThis supercomputer simulation shows the collision and merger of two disk-shaped galaxies. Stars in the disk of each galaxy are colored blue, while stars in their central bulges are shown in yellow. Red indicates dark matter that surrounds each galaxy. The total elapsed time for this simulation is one billion years.
This supercomputer simulation shows six galaxies merging to form a single giant galaxy. Toward the end of the simulation a large galaxy forms that "devours" other, smaller galaxies, a process called galactic cannibalism. (In ordinary galactic mergers, galaxies of about the same size are involved.) Galactic cannibalism may explain how giant elliptical galaxies form near the centers of rich clusters of galaxies, where galactic collisions are frequent.
The centre of our Galaxy: Sagitarius A*
Curved Spacetime
Physics can reconstruct the history of the universe up to the Planck-time ~ 1.35 .10-34 sec
Before that time QM and RT contradict
2D-Analogy: inflation of a baloon
• All points move apart a la Hubble
• There is no centre of the universe
• Space itself expands
Critical density : crit = 2.10-27 kg/m3
= /crit
Up to 300,000 yrs
Hot and opaque
Matter and radiation coupled
Universe cooled by expansion:
matter and radiation become suddenly decoupled
Universe becomes transparant
This is the oldest radiation
and the farthest we can possibly see
This radiation is the Cosmic Background Radiation (CBR)
Because of subsequent expansion the the universe this is now cooled to ~ 2.7 Kelvin
Since january 2003 a entire map
of the CBR is available
Isotropy Problem
Isotrope 1:10,000
CBR
Newest measurements indicate that space is almost flat and isotrope
Solution: inflation theory
Short after Plancktime space grew
during about 10-24 seconds a factor 1050
Newest measurements also indicate that redshift grows stronger than Hubble’s law
The expansion is accelerating !!!
Possible solution:
reintroduction of Cosmological Constant ?
What would Einstein say ???
Big Crunch : not likely
Big Sleep : 1036 yrs from now only low-energy radiation
