[extropy-chat] Note on "Random (effects without a cause)" comment

[scerir]

"gts"
> I don't understand how an unpredictable,
> undetermined event can be considered
> causal. Surely every caused event is determined
> if not also predictable.

We define cause as 'a specific preceding
event for an effect'. (The term 'preceding' 
depends on a specific clock and reference frame. 
Many - David Bohm among them - believe that 
there must be a 'cosmic' time, a sort of preferred 
reference frame. But this is another story.)

Now one problem is that many performed experiments,
using 'entangled pairs' and fast-moving Franson
time/energy interferometers, show there is no
time-ordering of events. Distinction between causes
and effects is impossible, or there is no time at all.
A sort of time-like non-separability, similar to 
the space-like non-separability (also known 
as non-locality) between 'entangled pairs'.

Worse than that. Assuming that two 'entangled'
particles run through different arms of 
an interferometer (i.e. a Mach-Zehnder, or a HOM),
with some speed (c or whatever), it is possible to show
that the interferential behaviour of these entangled 
particles (so called two-particle interference) 
depends on what we may insert in a place wich is AFTER 
the interference point (a place wich is supposed to be 
reached, by those entangled particles, AFTER they 
already met at the interference point).

          detector1
              |
              |
              |
 -------------i-----###--- detector2
|             |
|             |
|             |
^             |
|             |
|             |               
s ------>-----

s = source of entangled particles
i = interference point
### = area AFTER interference point

In these cases the usual, old, narrow concept 
of causality seems to be useless. 

s.