Okay, from what I understand, the cosmological redshift is due to the expansion of the universe. I'm confused as to how this works. I don't understand why, if the universe is expanding, that the waves don't just have farther to travel. I also don't understand what is waving or why other things don't get 'redshifted'. Why isn't my bed farther from the wall than it was yesterday? Also, how do we know that the redshift isn't due to a heavy object near the 'edge' of the universe? Could someone explain redshifting in further detail?