Einstein also predicted that light should bend near a strong gravitational field.

Why would this happen?

Why can the ants below only communicate with each other via the blue pathway?

And okay, if mass causes curvature of the Universe why doesn't the Universe collapse? What maintains its 'static' nature?

Einstein introduces the Cosmological Constant

The cosmological constant acts like a repulsive force which grows stronger with distance. Its a signature of vacuum energy being present what the hell does that mean?

Okay let's forget about all this and move forward 15 years where Hubble is assembling data on galaxy redshifts and distances.

To get distances, Hubble assumes that all galaxies have the same physical size:

Run the applet now but only in Netscape 4.06 and higher ....

Hubble's Original Data

Although noisy this data still lead Hubble to announce that the Universe was in uniform expansion:

V_r = H_o D

or

With the discovery of Universal expansion, Einstein declared his idea of the Cosmological Constant to be his "Biggest Blunder", as clearly the Universe was not static but was dynamic.

The implication of Hubble's discovery, however, was there must have been a time when all the galaxies were together in a very small place.

What does it mean to say the Universe is expanding?

Ask the Ants (try this at home!)