## The tilt in the arrow of time

In a 1980 paper in the Journal of Physics, I predicted that advanced radiation actually exists in small amounts, so that some information travels from future to present and from present to past.

How to test this experimentally? in my 1994 book *Time: Towards a Consistent Theory*, I argued that this “hypothesis” of a “tilt in the arrow of time meant that physics must be done using mixed-type functional differential equations. (This is not really a hypothesis, but is just the most general way of doing physics after relativity, but people didn’t see it that way for a century earlier.)

It is gratifying that the study of such equations is finally being taken up on a wider scale. The scientific report of the SDDE09 workshop at the Max Planck Institute in Dresden says:

“Four talks, delivered by Gernot Bauer, Dirk Deckert and C.K. Raju and Savio Rodrigues, considered the equations of motion of charged particles in the action-at-a-distance electrodynamics, which are a neutral mixed-type implicitly state-dependent differential equation, and their formulation and numerical solution as (well-posed) initial value or boundary value problems. These were perhaps the most challenging equations considered during the workshop”.