
Our quantum problem - r721
http://aeon.co/magazine/science/our-quantum-reality-problem/
======
chanon
With all this writing about the 'quantum problem' and quantum mechanics not
making sense, I don't understand why quantum theorists don't take pilot wave
theory and the oil droplet experiments more seriously.

[http://www.wired.com/2014/06/the-new-quantum-
reality/](http://www.wired.com/2014/06/the-new-quantum-reality/)

Also, having people with expertise in other fields (fluid dynamics in this
case) look at the problem is exactly what can create progress.

~~~
orbifold
It's because the problems mentioned in the article are primarily philosophical
in nature and not things most physicists, even quantum physicists, spend
actual time researching. For example anything related to the many world
interpretation or more generally the measurement problem, would make for a
terrible thesis topic, it also probably wouldn't get any funding (Pilot wave
theory in particular is explicitly excluded from receiving funding from the
NSF, see
[http://www.mth.kcl.ac.uk/~streater/lostcauses.html](http://www.mth.kcl.ac.uk/~streater/lostcauses.html)).
So the only people working on such things are professors well into their
tenure and even they will more likely write about such topics during the
family summer vacation.

~~~
jostylr
My thesis advisor does get NSF funding and he does Bohmian mechanics. I have a
very talented colleague doing this as well and he ended up with tenure
recently. But it is a very hard road.

I did a thesis on it which I am quite proud of. But I also left academia
proper though more due to my disgust with various aspects of the system
unrelated to the discrimination associated with Bohmian mechanics.

To be fair to your point, the successful ones pursuing this either hide out in
mathematics departments or keep their mouth shut until well-established.

------
fake-name
I find it fascinating that there seems to be this assumption that the universe
has to be trivially comprehensible to us.

Our brains are an emergent properly of the _large scale_ behaviour of the
universe. There is no reason we should even assume we're capable of
__comprehending __the small-scale universe 's properties, let alone that they
should "make sense" to us.

~~~
wyager
What fundamental limitation of human information storage/processing technology
would prevent us from "making sense" of the universe at a general level? By
"making sense", I mean coming up with a complete and consistent physical
model.

Based on previous experiences, _I_ suspect that the universe is governed by
relatively simple rules that lead to complex emergent behavior, which would
certainly be conducive to our understanding it.

~~~
vectorpush
> _What fundamental limitation of human information storage /processing
> technology would prevent us from "making sense" of the universe at a general
> level? By "making sense", I mean coming up with a complete and consistent
> physical model_.

The nature of that fundamental limitation may escape our grasp by definition.
The article at least presents the idea that the strange observations of the
quantum mechanical universe may sit outside the range of science. I think
there's some merit to the idea that humans, not as "willful" entities, but as
groups of particles swept up in a cosmic chain reaction, may face fundamental
limitations to the "scope" of what we can grasp about the nature of the
universe.

Of course, that could be totally wrong as well.

------
Strilanc
I really liked this article, which surprised me. Usually philosophical-ish
quantum writings are much worse than this.

The post does a good job of roughly outlining several interpretations, and
explaining why they're each a little weird or at least what the common
objections are.

Personally, I'm hopeful that quantum computers will shed light on the issue.
They make a lot of large-scale experiments possible, or at least significantly
easier.

------
PhantomGremlin
There is a large elephant in the room that was barely touched on in the
article: gravity. How does QM relate to gravity? Wikipedia puts it thusly[1]:

    
    
       Gravity has yet to be successfully included
       in a theory of everything. ... Theoretical
       physicists have not yet formulated a widely
       accepted, consistent theory that combines
       general relativity and quantum mechanics.
       The incompatibility of the two theories
       remains an outstanding problem in the field
       of physics.
    

The best attempt that I've seen so far is from a slashdot[2] discussion:

    
    
       Your momma so fat even if I'd entangle
       with her no information would be able
       to leave her event horizon.
    
          Nobody has managed to put gravitation
          and QM together yet, and you want to
          do it in a your-momma-so-fat-joke? Wow.
    

[1]
[http://en.wikipedia.org/wiki/Unified_field_theory](http://en.wikipedia.org/wiki/Unified_field_theory)
[2] [http://science.slashdot.org/story/09/02/19/2338245/human-
eye...](http://science.slashdot.org/story/09/02/19/2338245/human-eye-could-
detect-spooky-action-at-a-distance)

------
comex
For reference, someone else's argument in favor of many worlds:

[http://lesswrong.com/lw/q8/many_worlds_one_best_guess/](http://lesswrong.com/lw/q8/many_worlds_one_best_guess/)

I'm not sure it adequately supports its claim that "the debate should already
be over", but it's worth reading. It's not science, but when all the
interpretations other than collapse models predict the exact same
observations, there's only so far the math can take you...

~~~
shoyer
I agree. There is no debate or "problem" as far as quantum physicists are
concerned. I'm not sure most of us would call our belief "many worlds", but
you'll find very few who think that collapse is a real phenomena or that you
cannot describe the world in terms of wave functions.

The author of this article is in a very small minority. Of course, the silent
majority is silent because we generally have better things to do than
philosophize.

------
imaginenore
I disagree with the leap of "logic" that "we since can't predict/observe
microscopic events, therefore we can't predict/observe macroscopic events".

Just like because we can't predict turbulence, doesn't mean that fluid
dynamics is now completely useless.

Science is still useful - both practically and theoretically, even if the
universe won't ever let us see past quantum "stuff".

------
debacle
There is a lot of wiggle room in quantum mechanics when it comes to how we
perceive things compared to how they are. Minor changes in perception, or
looking at a problem even slightly differently could make everything click. A
big part of the problem with physics is that our observable universe isn't
very observable.

There are a lot of questions we just can't answer until we have the
instruments to take measurements at Planck scales, and it's likely that, at
those scales, everything that doesn't fit quite right will seem obvious, and
everything that niggles at the back of a physicist's brain will be put to
rest.

------
Animats
When you see "quantum" and "consciousness" in the same article, that's usually
a bad sign.

"Shut up and calculate" \- physicist David Mermin, on philosophizing about
quantum mechanics.

------
gaze
I don't see what the big deal is. Measurement is handled perfectly well by the
stochastic master equation, which can be obtained through bayesian inference.
Quantum mechanics is still thermodynamicish because we don't really know what
a wavefunction IS... I think that's still kind of an issue, but measurement is
something we understand just fine.

------
coldcode
Louis de Broglie thesis story is pretty fascinating. He wrote a short thesis
basically stating that particles can be considered as waves. The examiners
thought it was nuts but passed it to Einstein, who basically told them that
not only should they reward him his doctorate, but likely a Nobel as well
(supposedly).

------
wtbob
I suspect that quantum theory is like Ptolemaic epicycles: a great way to
mathematically describe observed reality, but fundamentally incorrect.

What's the _correct_ (or more correct, anyway) way to mathematically describe
reality? Beats me; I'm no physicist.

~~~
bsder
Then why do you think you have the wherewithal to pronounce that quantum
mechanics is fundamentally incorrect?

Seriously. The Standard Model has held up in spite of _numerous_ attempts to
break it. Physicists would _love_ to break the Standard Model as it would lead
to new, cool stuff.

Even things like hidden variables have been tested for. There aren't missing
variables.

Just because something doesn't match your personal experience does not mean it
isn't true.

~~~
axilmar
On the other hand, there can be another explanation for the interference
pattern that appears in the double slit experiment.

One such explanation might be the wavy nature of spacetime itself: any
excitation of the medium called 'spacetime' maybe introduces ripples in that
medium, causing the behavior of particles to seem as probabilistic, whereas in
reality it is not, it is simply chaotic in nature.

This makes much more sense than the concept of a particle being a wave until
the wave collapses.

And this theory ties in perfectly with relativity and gravity: particles
create spacetime ripples just like any other body does. With this explanation,
there is no need for multiple universes and other strange things. The hidden
variables might be the universe itself after all.

~~~
semi-extrinsic
Michelson and Morley called, they want their interferometer back. (In case
this is too much of an in-joke: your theory was experimentally proven to be
false more than a century ago.)

~~~
axilmar
No, what I am saying is different than the Aether theory.

The expansion of space time proves there is a medium.

Gravity proves there is a medium.

Frame dragging proves there is a medium.

So, this medium may be the one that causes the ripples and the waves; the
particles themselves are not waves in any case.

