[PatrickHenry]

The laws of physics are time-symmetric. You cannot distinguish a film of a ball bouncing up from the pavement from one of the ball dropping to the pavement and played backward. Entropy provides an 'arrow' of time but this is not an explanation; it is an observation.

Yes. But causality is always a one-way street, flowing from cause to consequence. I have no support on this in any of the physics literature, nor do any of the truly knowledgeable people on this board agree with me, but I regard causality as the principle "arrow" of time, and the only one which gives time what we perceive as its direction -- from past to future.

[longshadow]

causality placemarker (this placemarker is here cuz I want it to be)

[AMDG&BVMH]

Re: "But causality is always a one-way street, flowing from cause to consequence. I have no support on this in any of the physics literature, nor do any of the truly knowledgeable people on this board agree with me, but I regard causality as the principle "arrow" of time, and the only one which gives time what we perceive as its direction -- from past to future."

This sounds profoundly sensible to me. Hence, "elegant". Time is progression/process of the material entity. It is easier to visualize in biological processes, but non-living matter also has progression. The progression is due to causality: something is happening to/within the entity because of some causal action. Hence, time as we know it is continually resulting from causality. Yes, I think you have it. But then who am I? ;)

This is the problem Einstein and Schroedinger (there were a few others) had with the prevailing concensus of the interpretation to apply to QM. It was doing away with causality: the link between cause and effect. Quantum actions were not "caused" but "randomly occurring" fluctuations and etc. The free lunch business . . . Well, they never accepted that, even if they did not "win" the argument. So Einstein and Schroedinger would approve of getting casuality firmly back into the picture. Maybe your theory is the way it will happen . . .

Besides, even if all practicing physicists don't agree, isn't this more in the realm, at present anyway, of metaphysics, i.e. interpretation of the physics? And the interpretation is not the physics. The physics, the equations, work, whatever you say about them?

[Servant of the Nine]

Yes. But causality is always a one-way street, flowing from cause to consequence. I have no support on this in any of the physics literature, nor do any of the truly knowledgeable people on this board agree with me, but I regard causality as the principle "arrow" of time, and the only one which gives time what we perceive as its direction -- from past to future.

That is only because causality is defined to give a consistent arrow and a consistent rate to the passage of time.

SO9

[boris]

"Yes. But causality is always a one-way street, flowing from cause to consequence. I have no support on this in any of the physics literature, nor do any of the truly knowledgeable people on this board agree with me, but I regard causality as the principle "arrow" of time, and the only one which gives time what we perceive as its direction -- from past to future."

Careful.

In the first place, one can design a relativistic experiment in which effect 'seems to' preceed cause.

In the next place, if one believes in strict causality, one soon finds himself sliding down the slippery slope of determinism. I know this because I do and am.

Finally, several modern experiments have indicated that our notion of 'causality' is at best a rough-and-ready heuristic. For example, the 'quantum eraser' and similar experiments which apparently show that the past can be edited by events in the present.

--Boris