Can All Particles of a Cat Be in Superposition Simultaneously?

  • Context: Graduate 
  • Thread starter Thread starter durant35
  • Start date Start date
  • Tags Tags
    Decoherence
Click For Summary

Discussion Overview

The discussion revolves around the concept of superposition in quantum mechanics, particularly in relation to macroscopic objects like cats and tables. Participants explore the implications of decoherence and whether all particles of a macroscopic object can simultaneously exist in superposition, as well as the nature of states observed in everyday objects.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants question whether it is possible for all particles of a macroscopic object to be in superposition for an extremely brief moment before decoherence occurs.
  • Others argue that decoherence is a continuous process that prevents macroscopic objects from existing in superposition for any meaningful duration.
  • There is a discussion about the nature of mixed states versus pure states, with some participants suggesting that decoherence leads to an apparent collapse of superpositions into mixed states.
  • One participant mentions the Many-Worlds Interpretation (MWI) and its implications for superposition, suggesting that mixed states may be approximations rather than definitive descriptions.
  • Another participant emphasizes that after decoherence, macroscopic objects are not in superposition but rather in a mixed state, particularly concerning their position.
  • There is a proposal that if one adopts the ignorance ensemble interpretation combined with decoherence, one could conclude that macroscopic objects have definite properties at each instant, despite being in a mixed state.

Areas of Agreement / Disagreement

Participants express differing views on the implications of decoherence and the nature of states in macroscopic objects. There is no consensus on whether macroscopic objects can be considered to exist in superposition or if they are definitively in mixed states after decoherence.

Contextual Notes

Participants note that the discussion involves complex interpretations of quantum mechanics, including the measurement problem and the implications of different interpretations like MWI and the ignorance ensemble approach. The nature of decoherence and its effects on the properties of macroscopic objects remain unresolved.

  • #61
durant35 said:
What do you exactly mean or on what did you refer when you mentioned this amount of time?

I thought I was explicit. You can resolve the Schroedinger's Cat paradox in a number of ways. One way is you consider the cat and nucleus as an entangled system. But its not as good a model as I have been discussing which is closer to what's going on - although it probably has some explanatory advantages. At all times the classical objects the cat, the detector, the table etc etc are classical because they are always interacting with the environment.

The time came from your concern, that has been addressed in a number of threads you participated in, that because the time or interference terms or whatever is theoretically not exactly zero. It was pointed out very very small quantities can be taken as zero. But even after that it worried you. Hopefully you now understand its a non issue. As I said in one of those threads some get caught up in it. If you do then I can't help you because the whole decoherence program falls to pieces and I will not be drawn into arguing it.

Thanks
Bill
 
Last edited:

Similar threads

High School Question about quantum superposition
  • · Replies 2 ·
Replies
2
Views
2K
High School The Cat's Perspective: Can Macroscopic Bodies Be in Superposition?
  • · Replies 46 ·
2
Replies
46
Views
7K
Undergrad Can Decoherence Create a Superposition of Life and Death?
  • · Replies 15 ·
Replies
15
Views
3K
High School Psi-ontic view, macro objects and decoherence
  • · Replies 38 ·
2
Replies
38
Views
5K
High School Penrose collapse and Superposition
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Schrödinger's cat: what's the state?
  • · Replies 17 ·
Replies
17
Views
3K
Graduate Non-technical description of "superposition"
  • · Replies 10 ·
Replies
10
Views
3K
Graduate 'Genuine Decoherence' and Macroscopic Superposition
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad Difference between Quantum Superposition and Mixed States
  • · Replies 1 ·
Replies
1
Views
2K
Graduate Quantum Entangled Living Bacteria
  • · Replies 14 ·
Replies
14
Views
3K