On Tuesday, July 10, 2018 at 8:24:38 PM UTC-6, Brent wrote: > > > > On 7/10/2018 6:50 PM, agrays...@gmail.com <javascript:> wrote: > > > > On Tuesday, July 10, 2018 at 4:42:44 PM UTC-6, Brent wrote: >> >> >> >> On 7/10/2018 3:01 PM, agrays...@gmail.com wrote: >> >> *IIRC, the above quote is also in the Wiki article. It's not a coherent >> argument; not even an argument but an ASSERTION. Let's raise the level of >> discourse. It says we always get a or b, no intermediate result when the >> system is in a superposition of states A and B.. Nothing new here. Key >> question: why does this imply the system is in states A and B >> SIMULTANEOUSLY before the measurement? AG * >> >> >> Because, in theory and in some cases in practice, there is a direct >> measurement of the superposition state, call it C, such that you can >> directly measure C and always get c, >> > > > *Is c an eigenvalue of some operator? How can you always get c, if C is > not an eigenstate of some operator? And if it is an eigenstate, why do you > assert it is a superposition? AG * > > > You just don't get it. c is the eigenvalue of C. C is an eigenstate. >
*Don't underestimate. Yes, if one gets c, c must be an eigenvalue of operator C. AG* BUT it's also a superposition of A and B. It's a simple fact of vector > spaces that a vector can be the sum of other vectors. The only thing > tricky about QM is that it's in a complex vector space so the vectors get > scaled by complex instead of real numbers. And they are *simulataneously > *the sum of other vectors. > *The complex scalar field is not a problem; not even tricky. But a superposition does not necessarily mean the system is physically in both component states simultaneously, even if someone writes the state as a sum. That's what's assumed, without proof. Maybe I missed your proof or argument. AG* > > Brent > > > >> but when you have measured and confirmed the system is in state c and >> then you measure A/B you get a or b at random. The easiest example is SG >> measurements of sliver atom spin orientation where spin UP can be measured >> left/right and get a LEFT or a RIGHT at random, but it can be measured >> up/down and you always get UP. Any particular orientation can be >> *written* as a superposition of two orthogonal states. >> > > *I'm not clear what a left/right measurement is, and how it might be > measured. I assume you mean the directions perpendicular to Up / Dn. In > any event, how is this related to the simultaneity of Up / Dn? AG* > >> >> This is true in general. Any state can be written as a superposition of >> states in some other basis. But it is not generally true that we can >> prepare or directly measure a system in any given state. So those states >> we can't directly access, we tend to think of them as existing only as >> superpositions of states we can prepare. >> > > *I'm OK with superpositions, only their interpretation of simultaneity of > component states. We can measure Up or Dn, and represent the situation > before measurement as a superposition and calculate probabilities, but the > assumption of simultaneity seems unsupported and produces apparent > paradoxes. AG * > >> >> 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 everything-li...@googlegroups.com <javascript:>. > To post to this group, send email to everyth...@googlegroups.com > <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 everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
