what's with the phasing thing?

i sorry if this was posted but i was wondering how come only obi-wan and yoda, and later anakin know how to phase back to where the living people are, and that the other jedi's like mace windu aren't all phasing back to comeout and help luke like what yoda and obi-wan did? im sorry i may sound stupid but i was just wondering?

EV Edit: Heh. Light reading indeed. See link(s) posted below.

 

Some light reading:


Where's Qui-Gon Jinn's Ghost?
When Jedis Die...?
Why does Obi-Wan disappear when he dies but Qui-gon and Vader do not?
Now that you've seen Revenge of the Sith, are you OK with Hadyen as Anakin's Ghost in ROTJ?
Did Anakin Skywalker's body vanish after he died?