Yea, Yea. There is no theoretical reason time cannot be a negative quantity. But to get time to reverse it implies anti-grav. Like entropy, you can only reverse entropy by inserting energy into a system. And reversing time, IMNSHO, would require the kind of energy they don't have numbers for.

And as for the duality of light being a wave or quantum - I see that as an illusion. If you send one single photon through a dual slit it will end up in some place on the screen on the other side, having been buffeted by air molecules randomly. Send another and it appears in another random place. Keep sending and the dots build up into a refraction pattern. Only then is it a wave. The single photon got to the other side through one slit. I have seen what was presented as an experiment with single photons. For all practical purposes we perceive the wave because we deal in streams of photons, ie light.