"A new optical experiment provides further proof that quantum mechanics is not hiding some classical framework beneath its veneer of context-dependent observations."
ViewPoint - Physics highlights (Online Journal)
Article: Mind the (Quantum) Contextuality
Note: This article is a good example of how choices by a mind can alter the outcome of a physical experiment. Here it is expressed as a guessing game with a Name on a sheet of Paper (sealed in an envelope). They express it in this way so people can think in more familiar areas.
Quote from article:
In the “Who am I” game, a closed envelope containing
the name or picture of a celebrity is given to a player (say
Alice). The celebrity’s identity is known to all the other
players but not to Alice, who has a certain (agreed upon)
number of questions to ask the others in order to find out
the name in her envelope. Needless to say, the identity
of the celebrity is there in the envelope, regardless of
whether Alice is able to guess it or not.
Quantum observables do not have predefined values […]
That means Alice now has to mind the order of her interrogations. In
quantum “Who am I,” the name in the envelope could
change if Alice asks about the celebrity’s occupation before
asking where he or she was born. But the range
of questions matters as well. The answer to “male or
female?” may depend on whether or not Alice decides
to ask about the celebrity’s hair color. In terms of an
experiment, the outcome of an observation is critically
dependent on the assignment of a set of mutually compatible
(i.e., commuting) observables. In sum, quantum
theory minds the context within which observations are
performed. Even more strikingly, this contextuality is a
general feature of all quantum states, not just a select
Examples like this are very nice illustrations of how Mind and reality are quite coupled in an observable way. Actually, Free-will may be more appropriate than Mind.
p.s. the article is written for non-technical people. However - feel free to ask questions... non-technical is still technical to very many people !!
Very interesting article. Thank You John.
I could not figure out State Independent Contextuality (SIC), though. Could you please explain it to a layperson?
An intuitive feature of classical models (classical Physics/mechanics) is non-contextuality of measurements:
i.e. the property that any physical state has a value independent of other measurements being carried out at the same time.
In the example the "state" is a envelope with a card and picture on it.
The envelope, card and picture are the State (item of reality). Compatible measurements are things that are not directly done to the card in the envelope. Opening a window, observing the color of the envelope, holding the envelope up to see if you can "see" what is inside etc.-- these are compatible measurements. These leave the card state alone, and the historical context of those other measurements leaves the card/envelope unchanged.
However, a theorem ( KS - derived by Kochen, Specker) shows that non-contextuality is in conflict with quantum mechanics. QM requires any state-independence to be affected by contextual measurements. This is weird. if you put something somewhere, go to a room and come back... it may have changed. Ask a question about it, it may change.
State-Independent contextuality (SIC) is the weird property that compatible measurements have a Context. what did you do before the measurement, the order of things you do before measurement, etc. affects the State independently. This applies to ANY quantum state -- not just special states (like entangled items etc.
So, state contextuality has been known for special states prepared in special ways. However State-Independent means ANY quantum state is affected by the context of what happened/measured before you measure the state you are investigating.. Open the envelope and see a picture... might have been of a picture of Blavatsky but is now a picture of Anand Kumar!). The history of the items before you open it matter. Open window 10 cm. then see Joe Fulton. it is highly a No-Go theorem that says physical reality as we know it does not work that way. We live in a world inherently contextual, rather than classic Physics of non-contextual reality.
I hope that helps. this is a good question. I hope I answered it in a way that makes sense. Let me know..
Note: The example dealing with Macroscopic objects are extreme and used for illustrative purpose.
Bell's Theorem requires specifically prepared objects that are usually entangled in some way. That would be State Contextuality, State-Independent Contextuality means that QM actually requires contextuality independent of the state the item is in.
I wanted to clarify that so that people do not think it will happen to macroscopic objects. Decoherence effects come into play.. that allows common objects to behave more classically.
Thank You John. It is explained quite well.
Do you see any parallels between SIC and the four states of consciousness as described in the Mandukya Upanishad? The fourth one being the SIC.
I'm thinking on this one.
Really good question! It definitely has similarities.
p.s. I edited this post because the one story I told was done from memory. I need the article to reference. Better just to find that APS News article.