> On 27 Apr 2018, at 03:36, Brent Meeker <[email protected]> wrote: > > > > On 4/26/2018 5:55 PM, Bruce Kellett wrote: >> From: Brent Meeker <[email protected] <mailto:[email protected]>> >>> >>> On 4/26/2018 3:41 PM, Bruce Kellett wrote: >>>> From: John Clark <[email protected] <mailto:[email protected]>> >>>>> >>>>> On Thu, Apr 26, 2018 at 2:02 PM, <[email protected] >>>>> <mailto:[email protected]>> wrote: >>>>> >>>>> > How many times must I remind you that Feynman explained that very >>>>> clearly. >>>>> >>>>> 42. >>>>> >>>>> > Please repeat it. AG >>>>> >>>>> I originally sent this on December 14 2017: >>>>> >>>>> David Deutsch proposed a test of Many Worlds about 30 years ago in his >>>>> book "The Ghost In The Atom", but it would be very difficult to perform. >>>>> The reason it's so difficult to test is not the Many World's theory >>>>> fault, the reason is that the conventional view says that conscious >>>>> observers obey different laws of physics, many worlds says they do not, >>>>> so to test who's right we need a mind that uses quantum properties. >>>>> Quantum Computers have advanced enormously over the last 30 years so I >>>>> wouldn't be surprised if it or something very much like it is actually >>>>> performed in the decade or two. >>>>> >>>>> An intelligent quantum computer shoots photons at a metal plate one at a >>>>> time that has 2 small slits in it, and then the photons hit a >>>>> photographic plate. Nobody looks at the photographic plate till the very >>>>> end of the experiment. The quantum mind has detectors near each slit so >>>>> it knows which slit the various electrons went through. After each photon >>>>> passes the slits but before they hit the photographic plate the quantum >>>>> mind signs a document saying that it has observed each and every photon >>>>> and knows which slit each photon went through. It is very important that >>>>> the document does not say which slit any photon went through, it only >>>>> says that they went through one slit and one slit only and the mind has >>>>> knowledge of which one. There is a signed document to this effect for >>>>> every photon it shot. >>>>> >>>>> Now the mind uses quantum erasure to completely destroy its memory of >>>>> which slit any of the photons went through; the only part remaining is >>>>> the document which states that each photon went through one and only one >>>>> slit and the mind (at the time) knew which one. Now develop the >>>>> photographic plate and look at it. If you see interference bands then >>>>> the many world interpretation is correct. If you do not see interference >>>>> bands then there are no worlds but this one and the conventional quantum >>>>> interpretation is correct. >>>>> >>>>> This works because in the Copenhagen interpretation when the results of a >>>>> measurement enters the consciousness of an observer the wave function >>>>> collapses, in effect all the universes except one disappear without a >>>>> trace so you get no interference. In the many worlds model all the other >>>>> worlds will converge back into one universe because information on which >>>>> slit the various photons went through was the only thing that made one >>>>> universe different from another, so when that was erased they became >>>>> identical again and merged, but their influence will still be felt, >>>>> you'll see indications that the photon went through slot A only and >>>>> indications it went through slot B only, and that's what causes >>>>> interference. >>>> >>>> Quantum erasure involves more than just forgetting what happened. What >>>> about Zurek's "many records in the environment". If you know what >>>> happened, many traces of that result remain -- even if your memory is >>>> erased. Deutsch on the wrong track, yet again! >>> >>> Deutsch knows the difference, and he specifies quantum erasure, which >>> implies that the detection of welcher weg is never classical, i.e. it is >>> not decohered into the environment since if it were it could not be quantum >>> erased. Which is the point of my remark that maybe all that would be >>> proved is that quantum "detection" can't be conscious. I'm pretty sure >>> consciousness is a purely classical phenomenon. So Deutsch's scheme to >>> detecting welcher-weg but erasing the knowledge may retain the interference >>> pattern but just prove that quantum knowledge is not conscious...something >>> Borh might well say. >> >> My point was that if there is a record that a measurement was made, >> something irreversible has been extracted from the experiment. If the QC is >> "conscious", then it has to interact with something to make this >> irreversible record, so its quantum state is irreversibly changed. But you >> are probably right: if there is no decoherence, then there is no >> consciousness, since consciousness involves irreversible memory. > > There are experiments already performed in which the welcher weg is available > but is erased, even spacelike relative to detection > > https://arxiv.org/pdf/1206.4348.pdf <https://arxiv.org/pdf/1206.4348.pdf>
Quite interesting paper. > > (I wonder if the French appreciated the labeling of their apparatus BS-in and > BS-out?) Lol Bruno. > > Brent > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/everything-list > <https://groups.google.com/group/everything-list>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
