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LWN.net Weekly Edition for December 5, 2013
Deadline scheduling: coming soon?
LWN.net Weekly Edition for November 27, 2013
ACPI for ARM?
LWN.net Weekly Edition for November 21, 2013
Fedora 20 gets its name
Posted Sep 4, 2013 5:32 UTC (Wed) by Cato (subscriber, #7643)
Posted Sep 4, 2013 5:54 UTC (Wed) by tzafrir (subscriber, #11501)
Posted Sep 4, 2013 10:27 UTC (Wed) by cesarb (subscriber, #6266)
It both is and isn't a good name.
The cat experiment
Posted Sep 4, 2013 12:26 UTC (Wed) by tialaramex (subscriber, #21167)
Some modern interpretations do not give an absurd outcome for the cat experiment. In "many worlds" the timeline divides, irrevocably, into copies with dead or live cats and each observer finds themselves in one timeline or another with either a live or dead cat. In "ensemble" the experiment can't be assessed meaningfully except by repeating it and applying statistics, some of the cats die, some live, none are ever in an indeterminate state. The "objective collapse" family draw a line in the sand, the trick works with the inanimate atom but not with a cat.
Of course just because something seems absurd doesn't automatically mean it's not true. But when we have a choice in how to interpret things avoiding absurd interpretations seems wise, and that's why Schrödinger wrote this thought experiment.
Posted Sep 4, 2013 13:20 UTC (Wed) by hummassa (subscriber, #307)
Posted Sep 4, 2013 15:46 UTC (Wed) by andreasb (subscriber, #80258)
IANAPhysicist, but that is the idea behind quantum decoherence, where information leaking to other physical systems (and not necessarily a human observer / "consciousness") causes wave function collapse.
The problem is that the wave function collapse is just a kludge introduced to explain why we don't see quantum superposition in our everyday macroscopic lives and why we get semiclassical results with "measurements". There is no experimental evidence that wave function collapse is even a real thing. Hence other interpretations like "many worlds" that don't introduce a collapse in the first place.
Posted Sep 4, 2013 17:21 UTC (Wed) by nix (subscriber, #2304)
There is no experimental evidence that wave function collapse is even a real thing.
This explains why interpretations of QM can exist that do not include this 'collapse' monster, many of which do indeed have the wavefunction growing forever (the most famous of these is probably many-worlds, but there are others).
Posted Sep 4, 2013 17:15 UTC (Wed) by Cyberax (✭ supporter ✭, #52523)
Interpretations of QM are just that - they interpret the results.
Posted Sep 4, 2013 18:22 UTC (Wed) by markhb (guest, #1003)
Posted Sep 4, 2013 19:19 UTC (Wed) by rgmoore (subscriber, #75)
You don't have to worry about feeding and cleaning the litter box until the box is opened and you make an observation.
Posted Sep 5, 2013 3:29 UTC (Thu) by awalton (subscriber, #57713)
Posted Sep 4, 2013 15:33 UTC (Wed) by andreasb (subscriber, #80258)
> It both is and isn't a good name.
You won't know until you use it.
Posted Sep 4, 2013 14:03 UTC (Wed) by hpro (subscriber, #74751)
Posted Sep 4, 2013 15:13 UTC (Wed) by dashesy (subscriber, #74652)
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