There are a couple of theories about why, in Empire Strikes Back, when Luke is dueling with Vader, Luke decided to fall off the ledge.

Now, both of which are my personal speculation and from a complete lack of direct authority (after all, most of my experience with Star Wars looks something like this:

– I’m the jawa hugging the bride’s leg; when I say ‘hoodeedee’ I am being literal. This wedding occurred in southern California and was covered by the Wall Street Journal (page 1 no less)!

Theory 1. Luke commits suicide.

Knowing that you are a progeny of something evil is just too much. You can’t kill your father, yet you can’t bear the reality that you might have inherited some evil DNA. Killing yourself and essentially nipping the evil lineage in the bud appears to be a logical option; after all: “do, or do not – there is no try!”

Theory 2. Luke calls upon the midi-chlorians and, upon communing with them, subliminally senses that Leah is nearby.

OK I know that happens moments later, but then you underestimate the power of the midi-chlorians and how they are able to foresee what their hosts cannot even foresee.

Yes I realize that midi-chlorians don’t appear until the prequels but these are the origins of the “force” and essentially I’m saying that Luke used the force and the force told him that he could jump and somehow, survive. He took that leap of faith.