Retro Causalty, Retro Psychokinesis and the Possibility of Time Travel

What is time? Can we change things that have already occured?
Here are some links to get your cranium cranking.
Hold on to your hats.
RetroPsychoKinesis

Time Travel

Nostradamus

Changing the Past? article

Talks on Retro Causality:

That's enough for now.
Later,
Paul Parducci