How does Many Worlds theory explain Schroedinger's cat

Click For Summary

Discussion Overview

The discussion revolves around the Many Worlds interpretation of quantum mechanics, specifically in relation to Schrödinger's cat thought experiment. Participants explore how this interpretation accounts for the outcomes of the experiment, including variations in probabilities and the implications of universe splitting.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested
  • Meta-discussion

Main Points Raised

  • Some participants propose that when the box is opened, one universe contains a live cat and another contains a dead cat, suggesting that in a scenario with a 10% chance of survival, there would be one live cat and nine dead cats across different universes.
  • Others argue that the Many Worlds theory posits that the universe splits at every instant, with the cat's fate determined by the observer's universe, thus removing the necessity of observation in quantum mechanics.
  • A participant expresses uncertainty about the depth of coverage of Many Worlds in college physics courses, noting that while concepts like the uncertainty principle are taught, interpretations may not be included.
  • Another participant mentions that interpretations of quantum mechanics are often not addressed in undergraduate studies, viewing them as philosophical or theoretical rather than practical for most work in the field.
  • There is a recognition of the blurred line between philosophy and physics in discussions about interpretations like Many Worlds.

Areas of Agreement / Disagreement

Participants express differing views on the implications of Many Worlds, particularly regarding the nature of universe splitting and the role of observation, indicating that multiple competing views remain without consensus.

Contextual Notes

Some participants highlight limitations in their understanding and express uncertainty about the specifics of college curricula related to quantum mechanics and interpretations like Many Worlds.

Who May Find This Useful

This discussion may be of interest to students and enthusiasts of quantum mechanics, philosophy of science, and those curious about the educational treatment of complex interpretations in physics.

daf2
Messages
1
Reaction score
0
As I understand it, when Schroedinger's "box" is opened, then a dead cat comes into existence in one universe and a live cat in another. However, in a variation to this experiment, in which there is say a 10% chance of the cat living and 90% dying, when the box is opened does one live cat come into being in one universe and 9 dead cats appear in 9 identical universes.

If this is the case then as the 9 universes with the dead cats are identical would they merge into one, which overall has the end effect of making the live/dead odds of 50%
 
Physics news on Phys.org
The way I understand it, the many worlds theory doesn't say that the dead/living cat "comes into existence" at all, but rather that the universe splits at every instant in which the cat might die. It just so happens that every second, there's a (let's say) 50/50 chance of the cat dying. The cat you observe depends on which cat exists in your universe. So (for the sake of argument) for t=1, there's 2 universes, one where the cat's living, one where it's dead. at t=2, there's 3 universes. one where the cat's living, one where it JUST died, and one where it died two seconds ago. From my understanding, it removes the whole idea of "observation" from quantum mechanics... but I'm in absolutely no way an authority on these matters and have possibly gotten more things wrong than right. This is just how I understand it.
edit: also, from my understanding, these universes live in the same space but have decohered from one another, so that they're on another frequency, so to speak.
 
daytripper said:
The way I understand it, the many worlds theory doesn't say that the dead/living cat "comes into existence" at all, but rather that the universe splits at every instant in which the cat might die. It just so happens that every second, there's a (let's say) 50/50 chance of the cat dying. The cat you observe depends on which cat exists in your universe. So (for the sake of argument) for t=1, there's 2 universes, one where the cat's living, one where it's dead. at t=2, there's 3 universes. one where the cat's living, one where it JUST died, and one where it died two seconds ago. From my understanding, it removes the whole idea of "observation" from quantum mechanics... but I'm in absolutely no way an authority on these matters and have possibly gotten more things wrong than right. This is just how I understand it.
edit: also, from my understanding, these universes live in the same space but have decohered from one another, so that they're on another frequency, so to speak.

Off topic, but do they go over this stuff in college?
 
renob said:
Off topic, but do they go over this stuff in college?

I know they go over the uncertainty principle and such but I don't know if they address the many worlds interpretation of quantum mechanics. I'm a second year CSC major at CalPoly (SLO) and know a few physics majors who have taken a course called "Modern Physics", which is basically quantum mechanics but I've no clue how deep they delve into the subject matter. I wish that class was part of my degree, though.
 
We didn't go over interpretations at all in my undergrad study. They're not really necessary for most work you'll do in the field. It's either a philosophical question, or a highly theoretical one.
 
I love how easily the line between philosophy and physics is blurred. Seems something worth doing (I don't know if I'll ever forgive Carlin for mocking our space program. haha).
 

Similar threads

  • · Replies 41 ·
2
Replies
41
Views
7K
  • · Replies 17 ·
Replies
17
Views
4K
  • · Replies 76 ·
3
Replies
76
Views
10K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 63 ·
3
Replies
63
Views
6K
  • · Replies 59 ·
2
Replies
59
Views
13K
  • · Replies 143 ·
5
Replies
143
Views
12K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 18 ·
Replies
18
Views
4K
  • · Replies 16 ·
Replies
16
Views
4K