# Transactional Interpretation

1. Jun 13, 2007

### DrMoreau

I recently heard about the "Transactional Interpretation", and comletely failed to understand it. I then looked it up on Wikipedia, and became even more confused.
My main questions are:

1. I gathered that, after recieving a retarded wave, a detector will send out an advanced wave. What is classified as a detector?

2. How do the advanced and retarded waves interact?

3. How does this all give us a better idea of what happens during the double - slit experiment?

I would be grateful for any helpful responces.

2. Jun 13, 2007

### cesiumfrog

The default interpretation of QM is an initial value problem (like determining the motion of planets): you assume a particular initial state, and then you have some irreversible collapse process which leads to a random final state.

The problem is that strange irreversibility, which seems out of place in physics because it *introduces* "law-like" time-asymmetry. Transactional is one way of rephrasing QM as more of a boundary value problem (like determining the shape of a membrane stretched over some wire-frame): you assume both the initial condition and the final condition, and deduce what happened in between in a deterministic time-symmetric manner.

3. Jun 14, 2007

### lightarrow

Put in this way, the transactional interpretation seems more reasonable than the standard interpretation.

4. Jun 14, 2007

### DrMoreau

Thanks for the reply, cesiumfrog, but I'm not much of an expert at physics, so I didn't really understand your explanation. Are there any books or web pages you could recommend which give an easy-to-understand version of it?

5. Jun 14, 2007

### cesiumfrog

That's my bias coming through , time symmetry just seems preferable. In practice the "default interpretation" (irreversible collapse, as a mathematical tool for monkeys to make predictions, being careful never to interpret any of it as "real") is probably easier to calculate with. I'd actually be hesitant using/recommending *the* specific "transactional" interpretation, since the bloke who originated it seems to have come to a number of conclusions that are expected to contradict experiment.
For the philosophical concepts, I'd recommend Huw Price's "Time's Arrow and Archimedes Heel". If you also want to learn quantum mechanics, well, you'll basically need to do most of what is in a university physics degree.