[ExI] Passive Observations

[Ian Goddard]

Lee Corbin wrote:

> Very possibly, say, my eye has collected a photon 
> from VJ00443799+4129236, which is a binary star in 
> the Andomeda galaxy.
>
> In this case we say that I observed that photon or 
> that I observed the Andromeda galaxy.
>
> But does my observing that photon or that galaxy 
> actually cause any state change in the atom of  
> VJ00443799+4129236 which emitted that photon?


 It is passive observation, or becoming observable,
that affects subatomics. If photon detectors are
placed beside the double slits, allowing a photo to be
observed, a photon passes through one or the other
slit as local particle. But if no detectors are
placed, it passes through both slits as a wave.

 And read the description of Wheeler's delay-choice
experiment, starting toward the end of page 1 and
going on to page 2 here:

http://discovermagazine.com/2002/jun/featuniverse

 This paragraph speaks directly to your example:

 "By the time the astronomers decide which measurement
to make — whether to pin down the photon to one
definite route or to have it follow both paths
simultaneously — the photon [ from a distant quasar ]
could have already journeyed for billions of years,
long before life appeared on Earth. The measurements
made now, says Wheeler, determine the photon's past.
In one case the astronomers create a past in which a
photon took both possible routes from the quasar to
Earth. Alternatively, they retroactively force the
photon onto one straight trail toward their detector,
even though the photon began its jaunt long before any
detectors existed."

Wheeler's delayed-choice thought experiment was
confirmed in 1982 and more recently here:

http://www.sciencemag.org/cgi/content/abstract/315/5814/966

See also this page about the double-slit experiment:
http://zebu.uoregon.edu/~js/21st_century_science/lectures/lec13.html


http://IanGoddard.net

"What is 'real'? How do you define 'real'? If you are
talking about what you feel, smell, taste, and see,
then 'real' is merely electrical signals interpreted
by your brain." - Morpheus



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