
Schrödinger’s Cat When Nobody Is Looking - pmjoyce
http://nautil.us/issue/89/the-dark-side/schrdingers-cat-when-nobody-is-looking
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rkagerer
_One of the problems is that quantum theory is obscure (to say the least)
regarding what it claims about the nature of the world when no one is looking.
Is the involvement of a consciousness required for the theory to make sense,
and if so, does that include a mouse’s or a fly’s? In particular, the
specification of what constitutes a measurement is irreparably vague. Perhaps
all that’s needed is a large enough apparatus. But what’s large enough? And
what happens at the boundary? These issues are referred to as the measurement
problem._

In my utterly uninformed imagination I've reconciled this by defining
observation as the point where the observer (whether it be a simple apparatus
like the sensor on a photon counter, or a complex and squishy one like my
consciousness) becomes "intertwined" with the observation. i.e. Once the
information has reached some particle, that particle's view of the
waveform/event has collapsed.

It's easy to forget the actual conveyance of the information has some physical
manifestation (photons hitting my retina, electrons bumping against
transistors in an IC and eventually manifesting as dots on a screen which send
out those photons) and I picture those causal steps as propogating constraints
through the universe. Light speed sets a maximal boundary on how much of the
universe may be "intertwined" with the observable, but even if the data is
sitting on the computer next to me, until I take a peek (or otherwise subject
myself to any consequences stemming from them) those constraints haven't yet
permeated any of the bits of the universe that make up me.

Akin to how relativity permits two different observers to hold differing views
of some phenomena (eg. silmultanaety) this worldview allows me to imagine the
cat is both dead and alive even though my computer or the Geiger counter may
know the correct answer.

I'd love to hear from real quantum physicists whether this interpretation is
bunk or has some validity (and if so, whether someone else arrived at it
before me and gave the theory a name).

~~~
codethief
I sympathize with your view a lot and it is, in some way, also the way I
(degree in mathematical & theoretical physics) think about it.

Do note, however, that the wavefunction and its collapse are at odds with
special relativity and thus cannot be an object of reality. (Provided you're
interested in realism to begin with.) Take two entangled electrons, for
instance, which get sent out from the origin 0 in opposite directions towards
detectors A and B, respectively, which are placed at equal distance from 0.

Now take two observers, one moving in the direction from 0 to B and one moving
in the opposite direction. Then, depending on which observer's POV you take,
it is either detector A might makes the wavefunction of the two electrons
collapse (because the electron 1 reaches detector A and interacts with it
before electron 2 reaches detector B) in which case interaction of electron 2
and detector B doesn't do anything. Or, vice versa, it is detector B which
makes the wavefunction collapse but then detector A doesn't do anything
special.

Either way, if the collapse were actually something physical, both observers
would have to agree on the causality chain of events. But they can't. In fact,
varying the above setup a bit, they won't even in general agree on whether the
wave function of a given system has or has not yet collapsed.

~~~
archibaldJ
What I particularly find interesting is that there is a nice correspondence of
this in programming language theory where depending on the evaluation strategy
the same values are derived differently from a set of expressions i.e. values
are computed in different orders and different causality relationships arise
(causality in the sense of which expressions cause another expressions to get
evaluated e.g. call by value vs call by name) but ultimately you arrive at the
same result (or varying the initial “setup” may result in some expression not
being evaluated)

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galaxyLogic
This is a good new theory which makes SENSE as far as I can understand.

But, if we apply Occam's Razor then isn't the explanation to all quantum
weirdness simply that we live in a simulated universe?

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hleszek
So, I am missing something, how does it work with the double slit experiment ?
the result should never act as a wave without observation if we have
spontaneous collapse all the time ? Or is this spontaneous collapse quite rare
in practice ?

~~~
lisper
Yes, that's right. _Extremely_ rare. The only reason that the theory works at
all is that a single spontaneous collapse can propagate throughout a complex
system of entanglements and collapse the whole system.

The nice thing about spontaneous collapse is that it makes a testable
prediction: there should be a scale at which the behavior of an _isolated_
system starts to show divergence from quantum predictions. So far that
prediction has failed to be demonstrated, but people are still working on it.

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TheOtherHobbes
This seems like a reinvention of the Penrose Interpretation.

[https://en.wikipedia.org/wiki/Penrose_interpretation](https://en.wikipedia.org/wiki/Penrose_interpretation)

~~~
guerrilla
Both are collapse theories [1][2], but presumably not identical being that the
author is aware of Penrose's work and credits Penrose earlier in the article
for some terminology as well as acknowledging his influence on the theory in
the following footnote form the article:

> 6\. In this, we have been strongly influenced by considerations in this
> regard made over 3 decades ago by works such as Penrose, R. Time asymmetry
> and quantum gravity. In Isham, C.J., Penrose, R., & Sciama, D.W. (Eds.)
> Quantum Gravity II (1981); Wald, R.M. Quantum gravity and time
> reversibility. Physical Review D 21, 2742 (1980).

The first footnote tells us that the author is referring to GWR theory [3]
specifically (which is distinct from Penrose's):

> 1\. Ghirardi, G.C., Rimini, A., & Weber, T. Unified dynamics for microscopic
> and macroscopic systems. Physical Review D 34, 470-491 (1986); Pearle, P.
> Combining stochastic dynamical state-vector reduction with spontaneous
> localization. Physical Review A 39, 2277-2289 (1989); for a relatively
> recent review see Bassi, A. & Ghirardi, G. Dynamical reduction models.
> Physics Reports 379, 257-426 (2003).

1\. [https://en.wikipedia.org/wiki/Objective-
collapse_theory](https://en.wikipedia.org/wiki/Objective-collapse_theory)

2\. [https://plato.stanford.edu/entries/qm-
collapse/](https://plato.stanford.edu/entries/qm-collapse/)

3\.
[https://en.wikipedia.org/wiki/Ghirardi%E2%80%93Rimini%E2%80%...](https://en.wikipedia.org/wiki/Ghirardi%E2%80%93Rimini%E2%80%93Weber_theory)

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mannykannot
This article contains a consise explanation of the black hole information
paradox, and, for the first time, I feel as though I understand what the issue
is (assuming that it is not glossing over some important issues.)

