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Thank you Carrol!

i haven't said anything about the Quantum on this list
so far, as it is not exactly my speciality, although i
do know a bit about it.

The main reason I haven't said anything as i have had
experiences of explaining quantum to none physicists
and people with spiritual inclinations, and what
ALWAYS happens is that they igore what im actually
saying and make it mean whatever they choose to
believe it means.

This is incredibly frustrating.

NB - a very good book on quantum, space-time, etc is
The Fabric of the Cosmos by Brian Greene.  If anyone
is actually interested in what EXPERIMENTAL EVIDENCE
(and not what randomly tying in half understood ideas
with mysticism from centuries ago) tells us, this is a
great and very interesting read.

Tabitha


--- Carrol Cox <[log in to unmask]> wrote:

> Being somewhat bothered by the some of the
> statements on quantum
> mechanics made on this list, a couple weeks ago I
> queried a physicist
> friend on the topic and got the following reply.
> Carrol
> -----
> 
> something better: a set of experiments that
> presented particle and wave
> properties for one thing, along with several other
> mounting
> contradictions, forced a change in the structure of
> physical theory. the
> resulting theory forced us to better appreciate the
> already existing
> understanding that observing a phenomenon could
> influence the
> phenomenon. 
> 
> more details:  well.........ok, first of all, they
> are confusing two
> separate but related strands: wave-particle duality,
> and the uncertainty
> principle. so one is not "based on" the other. and
> second of all,
> influence of the obersever on the observed is NOT a
> quantum mechanics
> only phenomenon. 
> 
> historically, the early part of the 20th century saw
> some key
> experiments which brought into question whether we
> could seriously
> consider that something which we thought had a wave
> property now acted
> like a particle, and vice versa. so the either/or
> was gone. actually,
> they seemed to co-exist together in one experimental
> setup. and with
> that came the question: could there be a coherent
> theory that straddled
> both types of properties. 
> 
> and in the 1930's, we got an affirmative answer:
> there was a framework,
> odd as it seemed, that allowed us to see how we
> would detect the
> property "particle" in one setup, and "wave" in
> another. 
> 
> That was Heisenberg. 
> 
> Then Heisenberg asked about the "meaning" of the
> theory. Since the
> structure of physical theory had taken such an
> unexpected turn, he
> focused in on the newest oddity, that properties of
> a thing looked more
> like a pair-wise *operation* than a one dimensional
> scalar *value*: so
> position and speed once sounded like "*three* feet
> away" or "moving *20*
> MPH, whereas now it's more like (very, very
> crudely!!!!) "changed *from*
> three feet away *to* six feet away", or "energy
> jumped *from* three
> calories *to* six calories", and so forth. these
> operations had a
> strangeness when looked at pairwise, and made it
> appear one could not
> ascribe the *pair of properties* position AND speed
> of a given particle
> at any one time. so H went thru some thought
> experiments to show why
> this might be true, and they became dubbed as
> uncertainty relations, 
> 
> historically, because of the way the uncertainty
> relations were first
> presented, there was this interpretation that it was
> the act of
> measuring (observing) that caused the problem.
> whereas the modern view
> is that *pairs* of properties act more oddly than
> any *one* property
> taken in itself. so observer could also be some
> macroscopic measuring
> instrument, not just human consciousness. so thence
> all the
> observer/observed paraphernalia.
> 



		
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