5 ms·

There's a lot of truth in that, and the orthodox interpretation is indeed riddled with incoherence. But what fascinates me is that after so much effort, the qua

by n4r9 11y ago

There's a lot of truth in that, and the orthodox interpretation is indeed riddled with incoherence. But what fascinates me is that after so much effort, the quantum community seems to be further away than ever from coming to a consensus on interpreting the theory. Every proposed interpretation does away with some foundational issue, yet introduces another in the process.

ikeboy 11y ago
They may not have a consensus, but why do you think they're further away from consensus than they were in the past?
- n4r9 11y ago
  If you mean "what has led you to think they're further away from consensus": mostly just gut feeling, as a (younger) member of that community. I've not seen any rigorous and comprehensive studies of which interpretations garner the most support, but it does seem like popularity is currently divided between the orthodox and several other interpretations that have evolved from "niche" to "significant minority" in recent years. If instead you mean "by what process are they further away from consensus": I would suggest that the recent surge of research in quantum information theory has stimulated a greater interest in foundational issues, which in turn has led to an invigoration of the interpretations debate.
  - gfodor 11y ago
    http://www.preposterousuniverse.com/blog/2013/01/17/the-most-embarrassing-graph-in-modern-physics/ http://www.preposterousuniverse.com/blog/2013/01/17/the-most... In short Copenhagen still (sadly) rules the day, followed by many worlds and QIT.
    - n4r9 11y ago
      I meant "rigorous and comprehensive" to include "representative of the entire quantum community". That poll was conducted at a single conference and had 33 participants. The bias inherent in this approach can be seen when the same poll was conducted at two other conferences: http://arxiv.org/abs/1303.2719 http://arxiv.org/abs/1303.2719 http://arxiv.org/abs/1306.4646 http://arxiv.org/abs/1306.4646 In both cases, de-Broglie Bohm interpretations ruled the day. As the abstract of the latter paper states: > ...the results do strongly suggest several interesting cultural facts -- for example, that there exist, within the broad field of "quantum foundations", sub-communities with quite different views, and that (relatedly) there is probably even significantly more controversy about several fundamental issues than the already-significant amount revealed in the earlier poll.
      - gfodor 11y ago
        My bad, on a phone and recalled the link from a while back to share it.
      - williamjennings 11y ago
        My opinion is that the Copenhagen interpretation does not contradict DeBroglie in terms of nuclear chemistry, but solely thermodynamics. The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics. The work of t'Hooft is a more modern alternative for ensembles where the outcome is stochastic, rather than probabilistic. Photosynthesis has that property, as do many other enzymatic systems.
        n4r9 11y ago
        Not sure what you mean by "contradict". Certainly you won't easily find experiments for which the two offer different predictions. They are very different in terms of their ontology though: DeBroglie states that particles have definite positions and momenta at all times whereas Copenhagen does not.
        williamjennings 11y ago
        Most of the contradictions arise as epistemological forks in the context of molecular spectroscopy with nuclear decay events. Thusly, it is a question of whose theories to use, and the Born rule is moot when the distribution of particles is not gaussian. DeBroglie himself states that matter waves propagate according to a defined distribution; whereas Copehagen interprets that they are probabilistically distributed. In the former case there is a stochastic process, whereas it is only a random process in the latter case.
        n4r9 11y ago
        What do you mean by "moot"? The Born rule is simply that the probability of measuring a particle to be in a certain location is given by the squared amplitude of the wavefunction. This squared amplitude will generate the same predictions whether you are using deBroglie-Bohm or "Copenhagen" to imagine your underlying ontology. The difference in ontology being that deBroglie-Bohm is deterministic, i.e. particles have definite positions of which we are merely ignorant, whereas "Copenhagen" is (usually) non-realist, i.e. it is not meaningful to talk about the positions of particles until the moment we measure it.
omalleyt 11y ago
Pilot wave theory: the "weird effects" that QM displays are really just the result of space time being a thing that vibrates in a wave-like pattern influenced by mass. And the reason this is cool is because when you put everyday objects in situations like that stated above, they exhibit quantum interference and everything else.
- n4r9 11y ago
  So this is essentially what is meant by the "deBroglie-Bohm" interpretation. There is an underlying definite configuration of all matter, but it is "guided" deterministically by the wavefunction psi. This avoids issues associated with wave function collapse, but by no means does it rid us of all the "weird effects". In particular, the pilot wave is explicitly non-local, in that for a Bell-type experiment the choice of measurement in one location will (instantaneously) affect the physical state of affairs in the other location.

by n4r9 11y ago

ikeboy 11y ago

They may not have a consensus, but why do you think they're further away from consensus than they were in the past?

n4r9 11y ago
If you mean "what has led you to think they're further away from consensus": mostly just gut feeling, as a (younger) member of that community. I've not seen any rigorous and comprehensive studies of which interpretations garner the most support, but it does seem like popularity is currently divided between the orthodox and several other interpretations that have evolved from "niche" to "significant minority" in recent years. If instead you mean "by what process are they further away from consensus": I would suggest that the recent surge of research in quantum information theory has stimulated a greater interest in foundational issues, which in turn has led to an invigoration of the interpretations debate.
- gfodor 11y ago
  http://www.preposterousuniverse.com/blog/2013/01/17/the-most-embarrassing-graph-in-modern-physics/ http://www.preposterousuniverse.com/blog/2013/01/17/the-most... In short Copenhagen still (sadly) rules the day, followed by many worlds and QIT.
  - n4r9 11y ago
    I meant "rigorous and comprehensive" to include "representative of the entire quantum community". That poll was conducted at a single conference and had 33 participants. The bias inherent in this approach can be seen when the same poll was conducted at two other conferences: http://arxiv.org/abs/1303.2719 http://arxiv.org/abs/1303.2719 http://arxiv.org/abs/1306.4646 http://arxiv.org/abs/1306.4646 In both cases, de-Broglie Bohm interpretations ruled the day. As the abstract of the latter paper states: > ...the results do strongly suggest several interesting cultural facts -- for example, that there exist, within the broad field of "quantum foundations", sub-communities with quite different views, and that (relatedly) there is probably even significantly more controversy about several fundamental issues than the already-significant amount revealed in the earlier poll.
    - gfodor 11y ago
      My bad, on a phone and recalled the link from a while back to share it.
    - williamjennings 11y ago
      My opinion is that the Copenhagen interpretation does not contradict DeBroglie in terms of nuclear chemistry, but solely thermodynamics. The Copenhagen interpretation makes a leap of faith with the Born Rule as it is based on Maxwell-Boltzmann statistics. The work of t'Hooft is a more modern alternative for ensembles where the outcome is stochastic, rather than probabilistic. Photosynthesis has that property, as do many other enzymatic systems.
      - n4r9 11y ago
        Not sure what you mean by "contradict". Certainly you won't easily find experiments for which the two offer different predictions. They are very different in terms of their ontology though: DeBroglie states that particles have definite positions and momenta at all times whereas Copenhagen does not.
        williamjennings 11y ago
        Most of the contradictions arise as epistemological forks in the context of molecular spectroscopy with nuclear decay events. Thusly, it is a question of whose theories to use, and the Born rule is moot when the distribution of particles is not gaussian. DeBroglie himself states that matter waves propagate according to a defined distribution; whereas Copehagen interprets that they are probabilistically distributed. In the former case there is a stochastic process, whereas it is only a random process in the latter case.
        n4r9 11y ago
        What do you mean by "moot"? The Born rule is simply that the probability of measuring a particle to be in a certain location is given by the squared amplitude of the wavefunction. This squared amplitude will generate the same predictions whether you are using deBroglie-Bohm or "Copenhagen" to imagine your underlying ontology. The difference in ontology being that deBroglie-Bohm is deterministic, i.e. particles have definite positions of which we are merely ignorant, whereas "Copenhagen" is (usually) non-realist, i.e. it is not meaningful to talk about the positions of particles until the moment we measure it.

omalleyt 11y ago

Pilot wave theory: the "weird effects" that QM displays are really just the result of space time being a thing that vibrates in a wave-like pattern influenced by mass. And the reason this is cool is because when you put everyday objects in situations like that stated above, they exhibit quantum interference and everything else.

n4r9 11y ago
So this is essentially what is meant by the "deBroglie-Bohm" interpretation. There is an underlying definite configuration of all matter, but it is "guided" deterministically by the wavefunction psi. This avoids issues associated with wave function collapse, but by no means does it rid us of all the "weird effects". In particular, the pilot wave is explicitly non-local, in that for a Bell-type experiment the choice of measurement in one location will (instantaneously) affect the physical state of affairs in the other location.