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.

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