Hubble Deep Field - Physics Pages

thumb|right|300px|nice summary of the hubble deep field and big bang cosmology - way cool back

Hubble
Hubble is deeply way cool.

In the twenties Hubble made observations of galactic red shift. It showed that where ever we look things are moving away from us. And the further they are the faster they flee. V = H x D. Hubble's law. Velocity away is proportional to Distance away. If its twice as far away it is moving away twice as fast. The factor of proportionality, H, is called the Hubble constant, but it is actually a more complex function that changes with time.

Nice video making the key points and giving the key images. The wonders of the Hubble.

The universe is (we assume) the same in every direction in the large and the tiny - the middle is lumpy (as far as we can tell). The universe is (we assume) the same everywhere. No special places ... on the large scale. Isotropic (all directions same) and Homogeneous (same everywhere).

Stretch a rubber sheet. As you pull all parts move away from all other parts. And the further apart two spots are the faster they seperate. Rubber sheets obey a Hubble law of their own.

Space stretches. It may expand. It may contract.

Space is huge. The only way to measure it is with light. but seeing far is seeing back then. The farther, the backer. We see the universe at earlier times. The speed of light is constant.

Spacetime is expanding. so is Space.



13 billion years ago. The galaxies were much closer together long ago. You can see it in the pictures. Muchbefore that the universe was opaque plasma. It cooled and light could move. We see some of it now. The seperation is greater. The density lower. The universe is flying apart ever faster. You can see it if you look. It is beautiful.

'''A side note. '''

The atoms of carbon and iron and oxygen and calcium and all but the hydrogen are one and all stardust. The particular atoms in your fingertips, those exact ones, were made in the furnace at the heart of a star, stardust.