[ExI] Bad Epistemology?

[Bryan Bishop]

On 7/15/07, Lee Corbin <lcorbin at rawbw.com> wrote:
> Is my epistemology really screwed up at a fundamental level?
<tremendously irresponsible snip>

I sent off your email to a buddy of mine who gets to play with
particle physicists daily, and so some interesting discussion
developed. I would welcome anybody's comments, esp. the last part
concerning quantum amplitudes applied to macroscopic systems.

Note the messages below are time descending, so starting at the bottom
may eliminate unnecessary confusion.

On 7/16/07, Bryan Bishop <kanzure at gmail.com> wrote:
> > Regarding number 3, I'm not so sure I agree with the statement that an
> > object is a theoretical construct.  Perhaps this is being nitpicky, or
> > alternatively it's a mistake in my understanding of an object (I think the
> > latter is more likely).  But if we're willing to accept that quantum fields
> > are real in any sense, then I think we are required to also believe in
> > things like electrons (or whatever other name you might want to call them),
> > which are the quanta of their respective fields.  A similar, but slightly
> > weaker case could be made even for conglomerate objects like bayrons and
> > mesons.
>
> When you look at some old stone in the garden, you see that stone, and
> you have some thoughts and expectations, explanations, or call them
> theories if you must- the stone will stay roughly the same, maybe some
> layers of atoms and other particles will be stripped off, the photons
> of the sun will heat it during the day, etc.
>
> However, as particle theorists peer into these structures, they find
> that they so far have no smallest object to base their observations
> on. Any object is a theoretical construct- our painted picture of what
> we expect the complex of spacetime-mass to be doing. Like our stone in
> the garden outside the house.
>
> Shine some photons on an object, and you will know (as your training
> tells you) that some of the photons are not going back towards your
> eyes. This effectively means that the mass that you are examining is
> constantly interacting and changing- if we had very fine resolution of
> photons we would see in very quick moments that parts of the object
> are blind to us while others are more visible than ever before.
>
> Now ...
>
> >> 4. Objects as such---strictly speaking---do not reside in the
> >>   mind. Nor do they reside in 3-space, any more than the
> >>   number 6 resides in our minds or in space.
>
> You have to agree with that much. Our stone that we perceive when we
> walk into the garden is mentally represented in our brain with firing
> neurons that keep some persistent image in the visual cortexes. So,
> our envisioned stone exists in the mind, but whatever system is
> causing the interaction with the environment (through photons, the
> wind, thermal motion- again photons, etc.) that we observe, that too
> exists- not in our envisioned 3-space, which is our construct to play
> with the universe, but rather whatever it is that is really "out
> there".
>
> As for theories and ideas platonically existing: if by that he means
> that two children can imagine some data structure somewhat similar,
> then I would agree. The possibilities of the brain allow for similar
> functionality, though we can never know if what I imagine matches
> exactly what you imagine. Right?
>
> Re: objects and properties. Objects/systems have contexts, their
> influence upon the world etc. You call it spacetime history (maybe
> spacetimemass history, or add energy in there somehow), and I'd call
> it the actions they take that modifies the rest of the universe.
>
> Quantum amplitudes- can they be applied to macroscopic systems somehow
> and show that there is a quantum amplitude for my standing up at this
> moment and running around with my arms in the air making long-tailed
> macaque calls?
>
> - Bryan
>
> On 7/16/07, Kurtis Nishimura <kurtisn at gmail.com> wrote:
> > I suppose I should read this in the mindset of a realist, right?  Okay...
> > well even in that case, I have a few comments.
> >
> > Regarding number 3, I'm not so sure I agree with the statement that an
> > object is a theoretical construct.  Perhaps this is being nitpicky, or
> > alternatively it's a mistake in my understanding of an object (I think the
> > latter is more likely).  But if we're willing to accept that quantum fields
> > are real in any sense, then I think we are required to also believe in
> > things like electrons (or whatever other name you might want to call them),
> > which are the quanta of their respective fields.  A similar, but slightly
> > weaker case could be made even for conglomerate objects like bayrons and
> > mesons.
> >
> > I find number 4 a little bit baffling.  Again, maybe this is my own
> > misunderstanding.  But how can you, on the one hand in 1 declare that the
> > universe is made of real things, in 2 declare that space in the absence of
> > fields has no meaning, and then on the other hand in 4 declare that objects
> > do not exist in 3 space?  Is the distinction that when he says objects he
> > really means "chair" and not "*a* chair," or "*that* chair?"  From reading
> > 5, I don't think this is the case.
> >
> > I actually don't have much to say about number 5...
> >
> > But about that last bit.  I think the resolution to his problem of objects
> > having properties can be resolved by simply looking at the history of an
> > object.  This history may not be especially meaningful at a field theory
> > level, as the locations and times of events may not be well defined.  But
> > certainly on a macroscopic scale, in special relativity the entire
> > space-time history of an object can be followed by examining its world line.
> >  For example, while the container "has" a dozen eggs the eggs and the
> > container will follow the same world line.  The property of being bought at
> > the store last week indicates that the container's world line is tied to the
> > purchaser's (and the seller's, and the money's that changed hands, etc...)
> > in a very distinct way.
> >
> > Again, I stress this is part of the structure of macroscopic objects (i.e.,
> > ones that display particle-like behavior rather than wave behavior).  This
> > does not bother us in a field theory sense because in field theory the
> > properties of each object are quite limited: mass, angular momentum, charge,
> > etc.  Further, if you have two objects with identical properties they are
> > completely indistiguishable in every sense.  One electron cannot be
> > distinguished from another electron.  (For example, these two processes
> > cannot be distinguished from one another:
> > http://www.nscl.msu.edu/~nunes/ria1_files/slide0175_image330.jpg
> > )
> >
> > The region in between field theory and the macroscopic world is more of a
> > problem... so I avoid that for now and just admit that I need to learn more
> > about the decoherence process before making any sort of claim on what
> > happens in the middle ground.
> >
> > So... do you think that resolves anything?  Or have I just managed to
> > restate already known facts while mucking up his original arguments?
> >
> > -Kurtis

- Bryan