The Dalai Lama tries to get his head around the double-slit experiment...

[Glob]

Informative, with a couple of funny moments...

Parts 1, 2, and 3 below (parts 4, 5, and 6 available on YT), followed by a cartoon video explanation of the double-slit experiment.











And for those who are not already familiar with the double-slit experiment, here it is in a nutshell. The universe is very strange indeed...

[Goldenmane]

Big surprise. Bloke dedicated to magical bullshit has difficulty understanding shit that actually happens.

[Loki]

Fantabulists always have trouble with the word "observer". They often cannot grasp the concept that the word "observer" is not referring to a conscious entity.

[Darwinsbulldog]

Originally Posted by Loki

Fantabulists always have trouble with the word "observer". They often cannot grasp the concept that the word "observer" is not referring to a conscious entity.

Well, a word like "interactor" would be less metaphysically-loaded. I never use "observer" for that reason.

[the_gelf]

Originally Posted by Darwinsbulldog

Well, a word like "interactor" would be less metaphysically-loaded. I never use "observer" for that reason.

Hmm, but that would be the disproof of a xian god, would it not, that if it were truly omnipotent, it would interefere with the double slit

[Glob]

By the way, I highly recommend Parts 4, 5, and 6, where Anton Zeilinger talks about Quantum Entanglement and how it ties in with Quantum Information and Quantum Computing.

Originally Posted by Goldenmane

Big surprise. Bloke dedicated to magical bullshit has difficulty understanding shit that actually happens.

His reaction at 10:40 in Pt 1 certainly seemed to be that of someone who did not appreciate the strangeness of the result.

How about that biologist though? He was undoubtedly the most annoying person in the room.

Originally Posted by Loki

Fantabulists always have trouble with the word "observer". They often cannot grasp the concept that the word "observer" is not referring to a conscious entity.

Originally Posted by Darwinsbulldog

Well, a word like "interactor" would be less metaphysically-loaded. I never use "observer" for that reason.

I try to emphasise that the effect is due to measurement, not observation.

Originally Posted by the_gelf

Hmm, but that would be the disproof of a xian god, would it not, that if it were truly omnipotent, it would interefere with the double slit

Clever.

[Aldaron]

Okay, can someone with a more sophisticated cerebral cortex than mine please explain to me - using very small words - how the "observer" thing works? My understanding is that the act of measuring or observing or interacting with a quantum particle, in any way, alters its attributes.

At its simplest, bouncing an electron off another electron (to look at it in an electron microscope, for example), forces an interaction with the electron you're trying to measure and therefore causes it to no longer be innumerable "potentials", but an "actual" thing in a particular location.

Watching these things I'm starting to think I'm completely off-base...can someone set me straight?

Thanks...

[Glob]

@ Aldaron

I don't think you are way off base, but the following explanation may help...

Originally Posted by Wiki

Imagine a double slit experiment where quantum particles are fired towards the two slits. The quantum particles pass through the slits and hit a momentum sensor a distance of D behind the slits. The momentum sensor has the ability to be turned off and on via a pin that stops the movement of the sensor when it is hit by a quantum particle. When the pin is in place, no measurement of the momentum can take place. When the pin is removed, the sensor can recoil when struck by a quantum particle and by measuring the recoil determine from which slit the quantum particle came. If the pin is removed and we can detect from which slit the particle came, then the wave-like passage through both slits cannot occur and no interference pattern will develop. However if we put the pin in place, and can no longer determine from which slit the particle passes through, then an interference pattern can develop.

It is an unsolved problem in physics, called the Measurement Problem. There are a number of different interpretations, and I am not familiar with most of them. But, for example, there is the Many Worlds Interpretation, which says that each possible outcome occurs in reality, but in separate universes, and it is the measurement that determines which universe the observer will be in at the time of the observation. In other words, Wave Function Collapse does not actually occur. The description you gave is more similar to the Copenhagen Interpretation, which says that Wave Function Collapse does actually occur (the act of measurement causes the set of probabilities to immediately and randomly assume only one of the possible values).

Many physicists think that the effect is caused not by physical interference due to measurement, but by the creation of new information in the universe due to measurement. This is what Zeilinger means when he says that 'knowledge' may be more fundamental than reality.

Does that answer your question or not really?

[Glob]

Originally Posted by Glob

Many physicists think that the effect is caused not by physical interference due to measurement, but by the creation of new information in the universe due to measurement.

...others think that the laws of quantum mechanics make it impossible to gain information about an object without changing the state of the object.

[Darwinsbulldog]

Originally Posted by Glob

...others think that the laws of quantum mechanics make it impossible to gain information about an object without changing the state of the object.

There may be some hope here.....I have seen some physics papers [mostly not understood by moi ] in Nature & Science recently that hint that subtle nudging with fields, rather than brute bashing together of sub-atomic particles can allow the determination of position and momentum at the same time.