"A sentient being can't be aware of being in a superposition"

In summary, Sean Carroll discusses the concept of superposition and why we don't experience things in a superposition. He uses the example of a primitive creature with three neurons and a photon source and two mirrors to illustrate the difficulty of encoding a superposition state in the brain. He also mentions that the brain's ability to encode experiences must be more complex than a single neuron being active in a specific state. Carroll notes that this is a question for neurobiology and cognitive science, not physics.
  • #1
Swamp Thing
Insights Author
907
572
TL;DR Summary
In the linked video, Sean Caroll explains why, under the Many Worlds interpretation, we can't have the experience of seeing things like Schroedinger's cat in a superposition.

I'm trying to propose a simpler reason for this, but I need help.
Sean Carroll on why we don't see things in a superposition [30:44] ---
www.youtube.com/watch?v=5hVmeOCJjOU&feature=youtu.be&t=1843

Here's my attempt at a simpler reason (but I need some help).
In the figure, we have a photon source and two mirrors M1 and M2. M2 is 100% reflective, but M1 can be switched between absent, 50% and 100%.
  • If M1 is absent, the primitive sentient creature on the right sees a flash of light in its right eye.
  • If M1 is 100% reflective, the creature sees a flash in its left eye.
  • If M1 is 50% reflective, the creature is in a superposition of having seen a flash in the right and left eye.
After the stimulus is applied, signals go through a processor (the cloud in the center) and then activate one of three neurons.
Now here's a reasonable assumption:
(a) In order to be able to encode (and hence to experience) one of the above states, the creature must have at least one neuron (or other such element) that is active only in that state.

For example, the top neuron encodes the experience of "I saw a flash in my right eye"

And now here's a strong intuition that I have, for which I am unable to articulate a proof:
(b) It is impossible to design a creature such that one of its neurons will be activated only when the stimulus corresponds to a superposition.

===========
Firstly, I'd appreciate some feedback as to whether the above makes some sense.
Secondly, how can one prove (or disprove) the statement (b) above?
sentient.png
 
Physics news on Phys.org
  • #2
If each eye redirects the photons by mirrors and attempts to create an interference pattern, (in essence, completing the interferometer), then a photon reaching a dark band in the interference pattern would indicate that there the mirror was not at the 50% setting. But such a set-up would prevent the brain from ever knowing which eye saw the photon.

Otherwise:
Of course, we are assuming that the brain is in a super-position - and that perceiving super-positioned photons can put it into that state.

Since the mirror seems to be in full view of the creature, the creature could observe that it is half-silvered and therefore deduce that the photons are super-positioned and therefore, so is it (or he or she).

Or, if such brain super-positioning is so easily achieved, then it could keep the "I'm in a super-position" neuron firing at all times.

After all, what do we know about your "Photon Source". Are there variations in the photons emitted from it? Are those variations real or just super-positions of many possible variations?
 
Last edited:
  • #3
Swamp Thing said:
here's a reasonable assumption

No, it's not a reasonable assumption at all. If it were true, every time you had a neuron die (which happens all the time), you would lose the ability to have an experience. However your brain encodes experiences, it has to be more complicated than this.

Note, also, that this whole question of how the brain encodes experiences is not a question of physics, it's a question of neurobiology and cognitive science. Very few physicists have any familiarity with those fields, so you should not expect their speculations about how the brain works to be very informed.
 
  • Like
Likes Demystifier

Similar threads

  • Quantum Interpretations and Foundations
Replies
15
Views
243
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Quantum Physics
Replies
3
Views
1K
  • General Discussion
Replies
2
Views
2K
  • Sci-Fi Writing and World Building
Replies
15
Views
3K
Replies
10
Views
1K
Replies
2
Views
1K
  • Sci-Fi Writing and World Building
Replies
9
Views
4K
  • Biology and Medical
Replies
2
Views
5K
Replies
11
Views
4K
Back
Top