On 7/5/2018 3:55 PM, agrayson2...@gmail.com wrote:


On Thursday, July 5, 2018 at 2:03:46 PM UTC-6, Brent wrote:



    On 7/5/2018 11:27 AM, agrays...@gmail.com <javascript:> wrote:


    On Wednesday, July 4, 2018 at 10:57:06 AM UTC-6, Brent wrote:



        On 7/4/2018 1:57 AM, 'scerir' via Everything List wrote:

        *No. I am asserting that the INTERPRETATION of the
        superposition of states is wrong. Although I have asked
        several times, no one here seems able to offer a plausible
        justification for interpreting that a system in a
        superposition of states, is physically in all states of the
        superposition SIMULTANEOUSLY before the system is measured.
        If we go back to those little pointing things, you will see
        there exists an infinite uncountable set of basis vectors
        for any vector in that linear vector space. For quantum
        systems, there is no unique basis, and in many cases also
        infinitely many bases, So IMO, the interpretation is not
        justified. AG*

        ***SIMULTANEOUSLY*** was used by EPR in their paper, but
        that did not have much meaning (operationally, physically).

        Can we say that the observable, in a superposition state,
        has a ***DEFINITE*** value between two measurements?

        No - in general - we cannot say that.


        It's in some definite state.  But it may be a state for which
        we have no measurement operator or don't intend to measure;
        so we say it is in a superposition, meaning a superposition
        of the eigenstates we're going to measure.  So it does not
        have one of the eigenvalues of our measurement.

        Brent

    *
    *
    *So for the radioactive source, the superposed state, Decayed +
    Undecayed, does NOT imply the system is in both states
    simultaneously? *

    No, it is in a state that consists of Decayed+Undecayed.  So in a
    sense it is in both simulatnaeously.  If you are sailing a heading
    of 45deg you are on a definite heading. But you are simultaneously
    traveling North and East.  And if someone was watching you with a
    radar that could only output "moving north" or "moving east" it
    would oscillate between the two and you might call that a
    superposition of north and east motion.

    Brent


*I see. But as I have pointed out, there are uncountably many sets of basis vectors that result in the same vector along the 45 deg direction. Thus, it makes no sense to single out a particular basis and claim it is _simultaneously_ in both. *

That's where you're wrong.  It makes perfect sense if that's the only basis you can measure in.  That's why I gave the hypothetical example of a radar that could only report motion as northward or eastward.  In some cases, like decayed our not-decayed, we don't have instruments to measure the superposition state.  In other cases like sliver atom spin we can measure up/down or left/right or along any other axis.

*ISTM, this is the cause of many of the apparent paradoxes in QM such as Schroedinger's cat, or a radioactive source which is decayed and undecayed simultaneously. I have no objection using such a state to do a calculation, but I think it's an error to further interpret a superposition in terms of simultaneity of component states. What say you? AG*

I say use what's convenient for calculation.  Don't imagine your calculation is the reality.

Brent


    *Same for cat, Alive + Dead? Same for ( (Undecayed, Alive)  +
    (Decayed, Dead) ) for Schroedinger's composite system? If that's
    the case, why would anyone think these states are in any way
    paradoxical or contradictory? 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 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
    <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 everything-list+unsubscr...@googlegroups.com <mailto:everything-list+unsubscr...@googlegroups.com>. To post to this group, send email to everything-list@googlegroups.com <mailto: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.

--
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.

Reply via email to