agentredlum said:
If nobody is looking at it then everyone Must look somewhere ELSE. This requires a systematic search of the entire universe to complete the proof Bohr wants.
Drakkith said:
I don't follow you Dave. How could the moon, or anything else really, ever NOT be interacting with something else? Whether the oxygen atoms are on the other side of the wall or not, they are always withing the effect of countless fields right?
[Note: I’m not a professor of physics]
agentredlum &
Drakkith, I think
DaveC426913 explained it all very well. As said, a 'measurement' does not need to be a 'visual inspection' by humans; all it takes is a 'disturbance' to put the quantum state into a 'definite' state. As we all might have guessed – Einstein’s talk about the Moon is a 'teasing' metaphor to 'stress' Bohr a little bit (
they liked to joke around). However, as far as I know, the discussion between them where primarily on the level of the 'quantum world'.
Nevertheless, it’s quite clear that there’s no clear cut between the classical macroscopic world and the microscopic quantum world, and everything in 'our macroscopic world' is of course resting on the laws of the quantum world (
= QM rules! 
).
Furthermore, as humans we doesn’t often reflect on this – but 'our reality' consist mainly of emptiness, huge voids of emptiness (
and I’m not talking about the feeling when your favorite football team lose the game of the year ). We like to think of macroscopic objects as solid and compact, but they are mainly built up of emptiness, including the Moon...
For me personally, it feels a little bit 'odd' to think that the Moon would 'disappear & reappear' like a freaking "Morse code" if it could be completely "screened off/on". However, my personal feeling is not something QM cares about
, and I have discussed this matter with RUTA (
who indeed is a PhD Professor of Physics), and thought I had real 'tricky question' in showing him the picture of gold atoms, as we see them thru scanning tunneling microscope (
that are microscopic and thus shouldn’t 'exist'):
The positions of the individual Gold atoms
composing the surface are visible.
RUTA answered:
RUTA said:
This confusion is always generated by statements like "atoms and photons don't exist." Zeilinger has created interference patterns with large molecules (buckyballs, I think) and there's nothing in QM that says you can't get interference patterns using even bigger objects. So, do molecules not exist? Where is the "cut off?"
The "picture of atoms" you showed was generated by millions of photons per second. The belief is that the atoms are "there" whether we excite them or not. That's the source of the confusion. In the RBW "relational" view, or Bohr et al's "symmetry" view, or Zeilinger's "measurement" view, if you strip away the relations/symmetries/measurements, you lose everything. In the atomic view, you still have the atom "sitting there in space," it's just not interacting with anything, i.e., it's "screened off." Once you decide to construct "things," like the atoms in your picture, from relations/symmetries/measurements, rather than smaller "things," e.g., quarks and electrons, then you understand clearly that the atoms in your picture slowly disappear as you gradually reduce the number of relations/symmetries/measurements ("photons" in the language of "things") used to "see them." In other words, the relations (aka "photons" in "things" talk) don't allow you to "see the atoms," the relations "construct the atoms." So, given millions of photons per second, you're well into the classical regime, thus your "picture." This view makes it clear how the dynamical/causal classical reality of interacting "things" might obtain statistically from a more fundamental, adynamical reality of relations/symmetries/measurements (a la the Figure from our arXiv paper you posted earlier).
And the Moon (of course) consists of similar building-blocks in form of atoms...
(However, when I questioned RUTA about gravity the picture seems to be just a little bit 'unclear', and who can blame him – quantum gravity is still under investigation... )
RUTA is working in the forefront of all of this, looking for new explanations, and one working hypotheses, is that
everything is made up of interactions! What we see is the 'mirror image' of what really goes on at the QM level. Look at this picture of the two faces:
Then look at the 'thing' in between the faces that form into a vase – this "vase of interactions" is all that really is!
(i.e. according to RUTA ... 
)
agentredlum said:
In my opinion, an interesting aspect of EPR is that the 'interaction' is instantaneous violating speed of light limit.
Dave is right again, this is
not the case. There is no exchange of true information going on between entangled particles – thus
no superluminal speed (FTL). The 'only' thing you get is
correlations, which are completely
random to its nature, and you are only able to detect and see this 'pattern of correlations' by exchanging the measurement data at (maximum) the speed of light.
It’s beyond any reasonable doubts, and nowadays clear that the old classical world of
Local Realism is a dead parrot. What remains to be settled is whether the real nature of our world is non-local or non-real (or both!). According to Dr. Anton Zeilinger it’s the idea of reality (as we know it), which is at stake...
https://www.youtube.com/watch?v=kIzMZtQ9NwQ
