4 ms·
That depends on exactly what idea of determinism you have. If you mean something like phenomena can be described by the standard model, that's fine, but if it'
by Natsu 11y ago
That depends on exactly what idea of determinism you have. If you mean something like phenomena can be described by the standard model, that's fine, but if it's something like local realism, that's been busted pretty hard. This might prove more interesting than the linked article, though it was on HN previously:
http://www.nature.com/nature/journal/v409/n6822/full/409791a0.html http://www.nature.com/nature/journal/v409/n6822/full/409791a...
Local realism is the idea that objects have definite properties whether or not they are measured, and that measurements of these properties are not affected by events taking place sufficiently far away1.
[...]
Many experiments1, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 have since been done that are consistent with quantum mechanics and inconsistent with local realism. But these conclusions remain the subject of considerable interest and debate, and experiments are still being refined to overcome ‘loopholes’ that might allow a local realistic interpretation. Here we have measured correlations in the classical properties of massive entangled particles (9Be+ ions): these correlations violate a form of Bell's inequality. Our measured value of the appropriate Bell's ‘signal’ is 2.25 ± 0.03, whereas a value of 2 is the maximum allowed by local realistic theories of nature. In contrast to previous measurements with massive particles, this violation of Bell's inequality was obtained by use of a complete set of measurements. Moreover, the high detection efficiency of our apparatus eliminates the so-called ‘detection’ loophole.
- spacehome 11y agoThe Many-Worlds interpretation of quantum mechanics is consistent with local realism.
- Natsu 11y agoTrue, but it makes Occam spin in infinitely many graves.
- spacehome 11y agoI'm not sure why people believe this. I would address it here again, but better people than me have written on it: http://lesswrong.com/lw/q3/decoherence_is_simple/ http://lesswrong.com/lw/q3/decoherence_is_simple/.
- Natanael_L 11y agoWhat would happen if a particle measurement had a probability with irrational numbers (in every base)? What would the outcome be? And I feel that MW would need a pilot wave that carries the information for every parallel possible outcome for entanglement to work, wherein certain pilot waves cause universe splits starting from the point where they overlap and others merge - if you measure the spin of two entangled particles you get two waves that meet where X+X and Y+Y don't interact, but X+Y and Y+X does and thus create new universes. I don't see how the wave-less versions hold up when there for example are orientation-dependent probability and a ton of other crap like that. What else makes the particles interact with exactly the right universe? Edit: Not to mention how complex MW would have to be to explain the delayed quantum eraser experiment.
- spacehome 11y agoYou're thoroughly confused about what MW is.
- Natanael_L 11y agoIn what way? There's no one canonical MW either way, my version with growing parallel universe bubbles that merge or split is just my interpretation, as the other versions I've seen seem to be unable to address various issues
- spacehome 11y agoThere is a canonical MW interpretation. The MW hypothesis is just that reality is the evolution of the Schrodinger PDE on a configuration space with no other modification such as pilot waves or collapse required. The math is really quite simple (this simplest of any QM interpretation). It doesn't have parallel universes or bubbles as fundamental objects.
- Natanael_L 11y agoAnd by what mechanics does that happen? How do the universe "know" which particles should behave how in delayed eraser experiments, for example? It just... Happens? How are the particles "separated" and "merged" (in lack of better terms) in the configuration space?