[ExI] heaves a long broken psi

scerir scerir at libero.it
Sun Jan 24 16:10:26 UTC 2010


[Jeff] What a pleasure this is.  I've long admired the quality of your physics 
savvy.  And I look forward to responding to your comment. Problem is: how to 
disentangle the whimsy indicated by the two smiley's, from the serious.  
Anyway, here goes... First, I loved the "there is no passion at [a] 
'distance'."  I'm not at all sure what that means, but I love it, and I'm gonna 
let it simmer at length in my subconscious, cause "I need the eggs". Whenever a 
techno-weenie, er,... technophile summons passion into the techno-whoopie, 
well, I mean,...science fired by passion?  Yeah, baby, I'm for that.  (It's the 
Italian thing, isn't it?  The 'passion' connection....)

[s.] Well ... while 'action at a distance' appears as something brutal, like 
the possibility of sending FTL signals, or stuff, or energies, 'passion at a 
distance' appears to be a more gentle concept, like the possibility of FTL 
reciprocal 'influences' between the two space-like separated entangled 
particles, or the possibility of FTL hidden communications 'between' the two 
entangled particles (human FTL communication being excluded). Speaking of these 
things it seems important to trace-out the instrumental measurements, since 
there are lands, in the universe, in which there are no instruments, no men, no 
measurements, and no many-worlders, but there must be the entanglement for 
sure. But (as Mermin says) there is the possibilty of 'fashion at a distance'. 
In other words, both entangled particles (space-like separated) act and feel 
passion at the same time, a-causally and a-temporally, since it is impossible 
to say - at least for us humans and being the particles space-like separated - 
which one acts first, or feels passion first, and which then (see the so called 
'before-before' and 'after-after' Geneva experiments). In other words ... it 
does not make sense to speak of 'action at a distance' or 'passion at a 
distance'. The only actual concept being that of  'non-separability' of 
entangled parties. 
 
[Jeff] Okay, so now let me take a few deep breaths and calm down. "Self-
replicating machine systems, ...self-replicating machine systems,...self-
replicating machine systems,...etc.")(It's my mantra.Takes me to my 'happy 
place'...) Ok.  I'm all calm now. You wrote: So, for the bi-waves, there is no 
action at 'distance'... " Uh,... well, yeah.  You start with, "...very close 
but no."  But I don't see where we disagree, cause that's exactly what I was 
saying. There is no action at a distance.  I must have communicated poorly. 
Regarding wave-particle duality, ok, I've heard of that.  As I understand it, 
all the sparkling bits in our universe can be described using two equally valid 
formulations, the classical which gives us particles, and the quantum which 
gives us waves.  And it was my impression there is this idea that until 
observed/measured, any given bit is somehow "indeterminate", existing as both 
particle and wave, and in all acceptable configurations at once, but only in 
some probabilistic potentiality.  Part and parcel of quantum weirdness. Past my 
hat size. Makes my head hurt.

[s.] Yes, there is a smooth transition between the particle-like nature and 
the wave-like. The more you pretend to know, or, to say it better, the more it 
is possible to know (in experiments, like the 'which-path', etc.) the more the 
wave-like nature vanishes. 
'In an experiment the [quantum] state reflects not what is actually known 
about the system, but rather what is knowable, in principle, with the help of 
auxiliary measurements that do not disturb the original experiment. By focusing 
on what is knowable in principle, and treating what is known as largely 
irrelevant, one completely avoids the anthropomorphism and any reference to 
consciousness that some physicists have tried to inject into quantum 
mechanics.' -Leonard Mandel (Rev. Mod. Phys.,1999, p. S-274)
But - speaking in general, eh! - it is not a mechanical effect,  it is not a 
problem of a material perturbation, it is not disturbance. It is something like 
a principle of limited, finite, available quantity of information. It is not 
possible to know more than 'that'. If you extract 'that' quantity of 
information, or even when it is in principle possible to extract 'that' 
quantity of information well ... you are done.
'The superposition of amplitudes is only valid if there is no way to know, 
even in principle, which path the particle took. It is important to realize 
that this does not imply that an observer actually takes note of what happens. 
It is sufficient to destroy the interference pattern, if the path information 
is accessible in principle from the experiment or even if it is dispersed in 
the environment and beyond any technical possibility to be recovered, but in 
principle "still out there".' -Anton Zeilinger (Rev. Mod. Phys.,1999, p. S-
288)

[Jeff]  But here's the deal. If you send two entangled photons off in 
different directions -- the Aspect experiment? -- the experimental apparatus 
already allows you to treat them as particles.  How else can you send them off 
in different directions?  So the bi-wave is already (or is it 'still'?) also a 
bi-particle.  And isn't this, in fact, generally the case?  Can't I take any 
photon/photon wave (or massy baryonic or leptonic particle) at any time and 
describe it with equal validity using either the particle or wave protocol? 
That is, can't I put it in a box and describe it as a wave, open the box, look 
in, and describe it as a particle, put my hands over my eyes, treat the room as 
just a big box, and keeping my eyes closed, describe it as a wave
again.  Isn't the wave-particle duality a 24/7 thing?  Always on, so to speak, 
ready at every instant for a "reset" to simultaneous wave particle 
potentiality?

[s.] You can describe things using the particle picture, or the wave picture, 
or both (Bohmian mechanics), or Feynman's paths. Or you can use the quantum 
fields formalism (in general this is the choice). The wave picture sometimes is 
difficult, for conceptual reasons (ie, what they are made of), but sometimes 
the description is simpler with waves. But we do not know (before measurements) 
if  they are particles, waves, or fields, or ... all of them. (Feynman knew 
they were particles, and only particles.) But yes, during an experiment - i.e. 
a two-particle interference exp. with two entangled particles - you can erase 
the information you already got (i.e. about the which-way of a specific 
particle) and restore the wave-like nature of that specific particle. Again, 
there is no 'disturbance' effect here, since you are using joint observables 
like polarization and position, which of course commute. (Using other 
techniques - weak measurements - you can also 'undo' a measurement, or it seems 
so.)  

[Jeff] But I digress...  So you have these two photonic bits, produced by an 
experimental apparatus that allows us to assert with some confidence certain 
particle-associated parameters -- ie position and velocity in 3D space -- 
(which it seems (to me) we could cover our eyes and reformulate into wave-
associated parameters, cause physics takes no time outs), and we say "That 
one's over there", pointing off in the distance, "and the other one is over 
here", pointing to a photon trap on the laboratory bench.  And now you are 
prepared to go to the photon
trap and slap the captured photon around a bit until it (and it's 'distant' 
accomplice) decohere/disentangle.  Alternatively -- in recognition of the 
semantic challenges which confront us -- I could say, "Disturb the "photon 
trap" until the single quantum waveform which constitutes the "not-two" "not 
particles"collapses and spits out the result:  two particles localized in 3D 
space, or two new, no-longer-entangled quantum waveforms INSTANTANEOUSLY 
extending to the furthest reaches of 3D space, and whose waveforms might very 
well be mathematically superposed and seen yet again as a single waveform -- a 
component in the greater single waveform which is the entire universe. Damn!, 
there I go digressing again.
Okay, okay.  (Takes a deep breath and gets back to it.)  So you wrote: " 
Possibly, for the bi-waves, there is no even 'distance' " Yes, yes, that was 
precisely my point, but you threw me off with that "...very close, but no." In 
our 4D realm everything that manifests bears the features of 4D's. Can't escape 
that IN THIS REALM.  In fact, I'm inclined to posit that particle-ness can't 
exist without spatial and temporal separation. Classical physics is 4D 
spacetimey-ness. So your bi-waves can't exist in this realm without bearing the 
marks of and conforming to the rules of 4D spacetime. Those marks are two 
distinct photons at a known measurable distance, and with no possibility of 
intimate instantaneous contact (I assert).  Ergo, in our 4D spacetime,  
instantaneous action across distance must be be mediated by and in other 
dimensions. I avoided using the term "in contact" above, because "in contact" 
is 'spatial'.  It implies 4D.  Whereas, in other dimensions, what can be said 
of space and time?  Perhaps nothing.  We have space and time in our 4D's, and 
are much pleased, but that shouldn't prejudice us.  No reason to project what 
we know onto what we don't.  And hey, they're OTHER dimensions, they should be 
different, not some boring rehash of what's already been done.  (Okay, that's 
not really a 'logical' argument, more like an aesthetic one.) So if you want to 
assert that the bi-waves know no separation, know no 'distance', I'm ready to 
entertain that notion so long as it is restricted to some extra-dimensional 
context where the "rules" of existence may not need, may in fact exclude what 
we experience as space and time. 
Okay, I've embarrassed myself enough for one day. Best, Jeff Davis

[s.] Very close again. But there is another path, to be explored. We have 
space-time theories, which do not allow the possibility of FTL signaling 
(random FTL signaling or tachyons and other pathologies are perhaps allowed, 
but let us skip that). We have quantum principles (like the No-Cloning, the 
Linearity, maybe the Uncertainty Principle, etc.) which also - and 
independently - do not allow FTL signaling. So, there is the so called 
"Peaceful Coexistence" between quantum & relativity. But we also have that 
weird non-locality (rectius non-separability) between space-like separated 
parties, which is difficult to *explain* in the framework of space-time 
theories, and which is also (ie, according to John Bell) a huge violation of 
the "spirit" of Special Relativity. Thus, one have to introduce at least 
another 'landscape'. It is then possible that reality we experience is a 
superposition of two things. A sort of Quantum Operating System and the usual 
physical space-time scenario. The Quantum Operating System operates not in the 
real space, or space-time, but in a specific abstract space. In this abstract 
space there is linear algebra, there is superposition, there are no physical 
distances, thus there is non-separability between entangled parties. When we 
look at monitors in front of us we cannot see what/when/why/how the CPU and the 
operating system are processing at the same time, but we know there is a CPU at 
work. ... When we look at events in the space-time scenario we do not see what 
the Quantum Operating System is, behind that curtain, processing at the same 
time.



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