On Thursday, December 14, 2017 at 2:54:01 PM UTC, Jason wrote: > > The solution was proposed by Everett in 1957, collapse is a subjective > illusion. The dead cat and its history of decomposing for the previous > hour does not materialize out of nothing from the mere act of looking at it. > > > No measurement is made of the cat, the Geiger counter, or the atom, by > anyone outside the isolated system of the box, so according to the > Copenhagen Interpretation the superposition does not collapse. The cat is > both alive and dead. That is, until someone opens the door to peek inside. > In that instant, the wave function collapses and the system randomly > “decides” whether the cat is alive or dead. > >
> If the state collapses to that of the dead cat, what happens to the > experiences of the cat who was in the superposition of being alive and dead > over the past hour? Do they suddenly vanish as if they never happened at > all? Perhaps they never existed in the first place, as Bohr’s anti-realist > approach would answer. But this leads to another problem: if the cat is > observed to be alive, do all of its memories and experiences over the > past hour suddenly pop into existence? Is the cat’s experience of 15 > minutes ago ever experienced? > > > It is one thing to believe that microscopic particles might be in two > different states at once, but quite another to believe the same for a large > and complex system, such as a cat. The CI implies that a living, breathing > cat, with a consistent history and memories of the previous hour, can > instantly materialize from the simple act of observation. > > > Schrödinger's experiment has also been extended to highlight other > problems. The mathematical physicist Eugene Wigner discussed a thought > experiment known as Wigner’s friend. In it, Wigner’s friend is in a room > that is sealed off from the rest of the world and in that room is a box > containing Schrödinger's cat. The friend opens the box after an hour and > notices whether or not the cat is alive. Sometime later, Wigner opens the > door to the room to check on his friend. When does the wave function > collapse, when the friend checks on the cat, or when Wigner checks on his > friend? If it is when the friend checks on the cat, then the isolated > system, unobserved by Wigner, has already collapsed (in contradiction to > the CI). Yet, if it does not collapse for the friend checking on the cat, > this is another contradiction, for he has made an observation of a system > in a superposition. The CI seems to have difficulties handling multiple > observers. mea > > *I don't see how Wigner's friend presents a problem for Copenhagen. According to the CI, the wf collapses when the system measured, which is when the box is opened. What am I missing? The issue of the cat's memory is a different matter, problematic IMO. AG * > If one takes the stance that the first conscious entity to experience the > result of a measurement causes collapse, whether isolated or not, this > still leaves the problem of large macroscopic systems with complex > histories popping into existence through observation. If we replace the cat > with some unconscious device, like a sensor that prints off a receipt with > the result of whether or not the poison was released, then a conscious > observer opening the box causes the instantaneous appearance of the print > out, oddly, with ink that has long-since dried. It has a consistent history > seemingly invented at once. > > Einstein was most impressed with Schrödinger's paper, and in 1950 wrote > Schrödinger a letter of praise, saying “You are the only contemporary > physicist, besides Laue, who sees that one cannot get around the > assumption of reality, if only one is honest. Most of them simply do not > see what sort of risky game they are playing with reality—reality as > something independent of what is experimentally established. Their > interpretation is, however, refuted most elegantly by your system of > radioactive atom + amplifier + charge of gunpowder + cat in a box, in which > the psi- function of the system contains both the cat alive and blown to > bits. Nobody really doubts that the presence or absence of the cat is > something independent of the act of observation.” > > Einstein never accepted the quantum mechanics as a complete theory. To the > end of his life he searched for a theory that better fit his ideals of > realism, causality and determinism. But the answer he sought was there all > along: in the equations of quantum mechanics. Consciously or unconsciously, > however, the answer was simply too strange for anyone to consider, even for > a moment. It was not until 1957, more than three decades after quantum > mechanics was formulated, that anyone was bold enough to point out the > answer that was staring everyone in the face. That person was Hugh Everett > III. > > > Jason > > On Tue, Dec 12, 2017 at 3:04 PM, <[email protected] <javascript:>> > wrote: > >> Not every superposition of states implies interference. Connect the dots. >> AG >> >> -- >> 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] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at https://groups.google.com/group/everything-list. >> For more options, visit 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.
