A different picture of quantum surrealism

#1
"With its ideas of particles zipping in and out of existence, quantum mechanics is probably the kookiest-sounding theory in science. And our understanding of it is little helped by the mysterious “probability fields” most physicists say dictate the zipping.

But a more intuitive picture may lie beneath. As new research demonstrates, beneath the shroud of probability, particles can in fact be viewed as behaving like billiard balls rolling along a table – although in surreal fashion.

The result helps resurrect an 80-year-old picture of quantum mechanics, and provides one of the most stirring demonstrations yet of an effect Einstein called “spooky action at a distance”."

https://cosmosmagazine.com/physical-sciences/different-picture-quantum-surrealism
 
#2
"With its ideas of particles zipping in and out of existence, quantum mechanics is probably the kookiest-sounding theory in science. And our understanding of it is little helped by the mysterious “probability fields” most physicists say dictate the zipping.

But a more intuitive picture may lie beneath. As new research demonstrates, beneath the shroud of probability, particles can in fact be viewed as behaving like billiard balls rolling along a table – although in surreal fashion.

The result helps resurrect an 80-year-old picture of quantum mechanics, and provides one of the most stirring demonstrations yet of an effect Einstein called “spooky action at a distance”."

https://cosmosmagazine.com/physical-sciences/different-picture-quantum-surrealism
I haven't read paper, and only just skimmed article..., but it looks like more weak measurement baloney... I mean, you measure or you don't measure... and each measurement is separate and effects the system.
 
#3
I haven't read paper, and only just skimmed article..., but it looks like more weak measurement baloney... I mean, you measure or you don't measure... and each measurement is separate and effects the system.
I believe it was some sort of weak measurement thing yes. I wonder what Zeilinger or Aspect would have to say about this exp.
 
#5
I haven't read paper, and only just skimmed article..., but it looks like more weak measurement baloney... I mean, you measure or you don't measure... and each measurement is separate and effects the system.
I've got to read it more carefully, but if I'm understanding the article correctly its saying something more than that. The article suggests they are entangling two photons after which one is sent towards a standard double slit setup and the other towards a polarisation monitor. The article suggests that the choice of how to measure the polarisation correlated to which slit the other photon was detected to go through.



Here's the original paper: http://advances.sciencemag.org/content/advances/2/2/e1501466.full.pdf
 
#6
I've got to read it more carefully, but if I'm understanding the article correctly its saying something more than that. The article suggests they are entangling two photons after which one is sent towards a standard double slit setup and the other towards a polarisation monitor. The article suggests that the choice of how to measure the polarisation correlated to which slit the other photon was detected to go through.



Here's the original paper: http://advances.sciencemag.org/content/advances/2/2/e1501466.full.pdf
Nope, it's more weak measurement baloney, these experiments get more and more confusing, but when you strip them back to the fundamentals of QM the misunderstanding becomes apparent...
 
S

Sciborg_S_Patel

#7
Nope, it's more weak measurement baloney, these experiments get more and more confusing, but when you strip them back to the fundamentals of QM the misunderstanding becomes apparent...
Can you go into the failures of weak measurement when you get a chance? Or just post a link.

Ethan posted a critique of weak measurements a long time ago:

Are weak values quantum? Don't bet on it

Obtaining a weak value involves taking a weak measurement of a particle. It also – counterintuitively – depends on throwing out the majority of the results, carefully selecting only a few to keep in an effort to screen out particles which were knocked off-course by the act of measurement.

In this way, researchers believe they can gradually build up a picture of the typical behaviour of particles even between measurements. When these carefully gathered and screened measurements produce something unexpected and (apparently) quantum, that's called a weak value. Weak values are a whole new window into the quantum world.

Unless, of course, they're not. What if weak values aren't quantum at all?

"We're skeptical of the whole field," says Joshua Combes. Combes is a postdoctoral fellow at Perimeter and the University of Waterloo's Institute for Quantum Computing (IQC), and he has just published a Physical Review Letters paper critical of weak measurement.
Not to say he 100% agreed with the critique, as he also posted a response from Aharanov:

Comment on 'How the result of a single coin toss can turn out to be 100 heads'

It just feels like every weeks (days?) someone claims to have made quantum mechanics less weird, but only so long as you accept some other scientifically controversial stuff.

That said Bohm had a lot of interesting ideas regarding Psi, consciousness, even "quantum non-mechanics".
 
#8
Can you go into the failures of weak measurement when you get a chance? Or just post a link.

Ethan posted a critique of weak measurements a long time ago:

Are weak values quantum? Don't bet on it



Not to say he 100% agreed with the critique, as he also posted a response from Aharanov:

Comment on 'How the result of a single coin toss can turn out to be 100 heads'

It just feels like every weeks (days?) someone claims to have made quantum mechanics less weird, but only so long as you accept some other scientifically controversial stuff.

That said Bohm had a lot of interesting ideas regarding Psi, consciousness, even "quantum non-mechanics".
Yeah, but quite frequently we get more evidence that it is really weird. The recent loophole free experiments are one. When they manage to put a bacterium in superposition (which is what they are planning) that will be a prime example
 
#9
Nope, it's more weak measurement baloney, these experiments get more and more confusing, but when you strip them back to the fundamentals of QM the misunderstanding becomes apparent...
Sound or not, these guys have a damn good sense of humour!

Here, we perform an experiment using the spin of particle 2 as carrier of the Welcher Weg information, as per the above theory. We determine the trajectories of particle 1 in an operational manner that does not rely on a particular interpretation of quantum mechanics (9), as realized by Kocsis et al. (7), using weak measurements of velocity postselected on the positions of the particlesThe particles in this article (Although “the particles in this article” is in this particular article, consider “the particles in an article” as part of an article. As any articulate party would know, the particles in “the particles in an article” are “the” and “in,” whereas the articles in “the particles in an article” are “the” and “an,” but the particular article in “the particles in an article” is “the.” “p.s.” is all that is left when you take the “article” out of “particles.”) are photons, as was the case in Kocsis et al.
 
S

Sciborg_S_Patel

#10
Yeah, but quite frequently we get more evidence that it is really weird. The recent loophole free experiments are one. When they manage to put a bacterium in superposition (which is what they are planning) that will be a prime example
You mean this sort of thing? ->

It’s official: the universe is weird. Our everyday experience tells us that distant objects cannot influence each other, and don’t disappear just because no one is looking at them. Even Albert Einstein was dead against such ideas because they clashed so badly with our views of the real world.

But it turns out we’re wrong – the quantum nature of reality means, on some level, these things can and do actually happen. A groundbreaking experiment puts the final nail in the coffin of our ordinary “local realism” view of the universe, settling an argument that has raged through physics for nearly a century.

Teams of physicists around the world have been racing to complete this experiment for decades. Now, a group led by Ronald Hanson at Delft University of Technology in the Netherlands has finally cracked it. “It’s a very nice and beautiful experiment, and one can only congratulate the group for that,” says Anton Zeilinger, head of one of the rival teams at the University of Vienna, Austria. “Very well done.”
 
#11
Can you go into the failures of weak measurement when you get a chance? Or just post a link.

Ethan posted a critique of weak measurements a long time ago:

Are weak values quantum? Don't bet on it



Not to say he 100% agreed with the critique, as he also posted a response from Aharanov:

Comment on 'How the result of a single coin toss can turn out to be 100 heads'

It just feels like every weeks (days?) someone claims to have made quantum mechanics less weird, but only so long as you accept some other scientifically controversial stuff.

That said Bohm had a lot of interesting ideas regarding Psi, consciousness, even "quantum non-mechanics".
I don't have any links. If you understand some of the very basic principles of QM, you can just see that weak measurements often get used inappropriately by nutty people.
 
S

Sciborg_S_Patel

#15
Yeah, I mean that's pretty fuckin weird itself.
From what I gathered from a quick survey, here's one of the best criticism on weak measurements:

Are Weak Measurements Really Measurements?


Weak measurements can be seen as an attempt at answering the Which way? question without destroying interference between the pathways involved. Unusual mean values obtained in such measurements represent the response of a quantum system to this forbidden question, in which the true composition of virtual pathways is hidden from the observer. Such values indicate a failure of a measurement where the uncertainty principle says it must fail, rather than provide an additional insight into physical reality
 
#18
I don't pretend to understand the implications of what they have done, I've done very little reading on quantum computing.

But it seems very clear to me that QM tells us there is no physical state existing between measurements, otherwise you won't be able to make any sense of your experiments.

Yet we have the article trumpeting... "Real objects don't just appear somewhere from nothing. But the experiment seems to defy this." which I suppose is their way of suggesting that this implication of the experiment defies QM... which is incorrect. It defies the idea of classical physics, but we've known that since the early 1900's.
 
#19
I don't pretend to understand the implications of what they have done, I've done very little reading on quantum computing.

But it seems very clear to me that QM tells us there is no physical state existing between measurements, otherwise you won't be able to make any sense of your experiments.

Yet we have the article trumpeting... "Real objects don't just appear somewhere from nothing. But the experiment seems to defy this." which I suppose is their way of suggesting that this implication of the experiment defies QM... which is incorrect. It defies the idea of classical physics, but we've known that since the early 1900's.
People find it unnerving I suspect, that the world doesn't work by our intuitions. I wonder if its a sort of ego trip. We are lords of creation, when in reality, we're highly evolved (debatable) primates with limited senses, viewing the world only in a way that stops us from being eaten by a tiger.
 
#20
People find it unnerving I suspect, that the world doesn't work by our intuitions. I wonder if its a sort of ego trip. We are lords of creation, when in reality, we're highly evolved (debatable) primates with limited senses, viewing the world only in a way that stops us from being eaten by a tiger.
I get the feeling that what we experience is correct in some way, it's just that how we've come to understand how it fits together isn't.

As an example, from one perspective, some people might seek out coherence... If I gave a simplistic example...

1. You might move to a specific spatio-temporal location (go to a football ground of a team you support),
2. You do this because you've stored access to this pattern in your networks (you have been to football matches before and had a good time),
3. some other people gathered there with you are self-selected as having similar compatible networks (they have enjoyed going to football matches to watch this team in the past).
4. All of you experience a similar sensory input, from the environment of the football match. I.e. You all see the same player score a goal at the same moment etc. (your similar networks are activated in a similar way by the sensory input).
5. These input patterns of activation onto your similar networks become coherent, not just with the past, but across space as well. The fans become a little more quantum coherent with each other because they've improved the odds of coherence.
6. In this situation, that coherence is what people are seeking, not the football match.

I dunno if that makes any sense. It's just one example, but what I'm trying to suggest is that the football game itself may be totally incidental... compared to some other underlying reason why we do things together, or by ourselves etc.

That somehow, how we popularly understand the reason to go to a football match is not quite correct.
 
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