Apparently Abraham was aware of the Rich Man's doings on earth:
Luke 16:25But Abraham said, Son, remember that thou in thy lifetime receivedst thy good things, and likewise Lazarus evil things: but now he is comforted, and thou art tormented.
And Hebrews 12 says that we are surrounded by a cloud of witnesses.
Hebrews 12:1Wherefore seeing we also are compassed about with so great a cloud of witnesses, let us lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us,
Revelations says that the souls of the martyrs are aware of the events on earth.
Revelation 6:8-10 (King James Version)
8And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.
9And when he had opened the fifth seal, I saw under the altar the souls of them that were slain for the word of God, and for the testimony which they held:
10And they cried with a loud voice, saying, How long, O Lord, holy and true, dost thou not judge and avenge our blood on them that dwell on the earth?
So, I would say that, yes, they can hear us.