Search FQXi


RECENT FORUM POSTS

Vladimir Rogozhin: "John, Unfortunately this essay isn't copied for machine translation of..." in Why Quantum?

Kjetil Hustveit: "Hi georgina, Thank you for showing interest in this topic. I think it's..." in Alternative Models of...

gil ayala: "wow .. thank you for your clarity. i'm not a math person, but as i read..." in Melting Spacetime

Jason Wolfe: "Peter, Oh wait, let me guess. You can go faster than the speed of light..." in The Quantum Pet Store:...

Jason Wolfe: "Hi Peter, Did I read it right, that the article Classical reproduction of..." in The Quantum Pet Store:...

Susan Mulloy: "My g+ site has many of the pictures you are looking for. I am an Artist so..." in The Quantum Truth Seeker

Georgina Parry: "Hi Kjetil, You wrote "This does not rule out that we are part of some..." in Alternative Models of...

Steve Agnew: "Yes, there are flaws and pathologies in GR. Any theory that replaces or..." in Why Quantum?


RECENT ARTICLES
click titles to read articles

The Quantum Truth Seeker
Watching particles fly through an interferometer might help to unveil higher-order weirdness behind quantum theory.

Quantifying Occam
Is the simplest answer always the best? Connecting Medieval monks to computational complexity, using the branch of mathematics known as category theory.

Heart of Darkness
An intrepid physicist attempts to climb into the core of black hole.

Why Quantum?
Entropy could explain why nature chose to play by quantum rules.

Reality's NeverEnding Story
A quantum version of Darwinian natural selection could enable the universe to write itself into being.


FQXI ARTICLE
September 20, 2014

De-Spooking Quantum Mechanics
Einstein wouldn’t have found entanglement so strange, if he’d thrown out a key pre-twentieth-century misconception.
by Graeme Stemp-Morlock
FQXi Awardees: Wayne Myrvold
July 13, 2011
Bookmark and Share


WAYNE MYRVOLD
University of Western Ontario
There’s a picture of Wayne Myrvold in Greenwich Village, New York, holding a concertina surrounded by hundreds of other ancient looking musical instruments. If you didn’t know him, you’d be forgiven for thinking the associate professor from the University of Western Ontario in London, Ontario, Canada, is a trained musician.

He’s not.

In fact, Myrvold is a philosopher of science and he has no idea how to play the concertina. But rather than take conventional music lessons, he enjoys the challenge of trying to figure out the instrument in his own way. Myrvold takes a similar approach to understanding quantum mechanics: He knows the standard answers from physicists, but he hopes that his own philosophical take will illuminate some of the theory’s famous peculiarities and will show that its spooky reputation is unwarranted.

"If someone tells me that quantum mechanics is weird, counterintuitive and strange, but you should just accept that we live in a strange counterintuitive quantum world, I’ll say okay but tell me what kind of world that is," Myrvold says.

In the weird quantum realm, subatomic particles can be in two places at once, or exist in multiple energy states, before anyone looks at them. The standard explanation is that before you observe it, a quantum object is described mathematically by a smeared out wavefunction, which tells you the probability of finding it in any one location, or energy state. When you make a measurement, that wavefunction "collapses" into one set location and energy level. Prior to that observation, however, you could not predict what the outcome of the measurement would be.

That’s the textbook answer. But, says Myrvold, even if you can wrap your head around wavefunction collapse, another quantum phenomenon—entanglement—makes everything problematic. Entangled particles are intertwined in such a way that measuring the properties of one seems to instantaneously affect the properties of its partners. Einstein famously denounced entanglement as "spooky action at a distance" because this communication appears to happen faster than the speed of light—violating the universe’s speed limit, set by his theory of relativity. This feature of quantum mechanics is called non-locality.

"To comply with relativity, you don’t want the possibility for faster than light signaling," explains FQXi-member Daniel Bedingham, a physicist who has also wrestled with wavefunction collapse, independently from Myrvold, at Imperial College London, UK.

Collapsing Misconceptions

Myrvold, however, believes that any seeming violation of relativity is an illusion. He argues that if we throw out one of our pre-20th century misconceptions, we’ll understand that there’s nothing spooky going on at all. The troublesome notion that should be consigned to the garbage is called "separability." It is the idea that if we know everything about one particle in one location and everything about another particle in a second location then we know everything about their combined system.


UNTANGLING ENTANGLEMENT
Could a new philosophy shed light on photon experiments?
Credit: IQOQI, University of Vienna
Separability is something we take for granted in every day life, and that may be why it is so embedded in our minds. But in quantum mechanics, the whole is much more than the sum of its parts, explains Myrvold. "If you take quantum mechanics seriously, it’s separability that you have to give up," he says. "When particle A and particle B are in an entangled state then telling you everything there is to say about particle A and telling you everything there is to say about particle B doesn’t tell you everything there is to say about the combined state about the particle A plus particle B system."

If you can free yourself from assuming separability, Myrvold argues, then when you observe one part of an entangled system, you will not be fooled into thinking of it as a separate object and become sidetracked worrying about how it can influence other separate objects. Myrvold believes that this misunderstanding leads us to falsely associate a single reference point in time with that part of the system, skewing our perception of what can happen to the rest of the system and when.

With an FQXi grant of over $56,000, Myrvold will be working out just how to weave non-separability into quantum mechanics explicitly, so that its not longer perceived as a strange and mysterious byproduct of the theory, but as a central—normal—feature. In addition to preparing a series of papers, he plans to work with other experts, both in philosophy and physics, at various workshops.

If you take quantum mechanics
seriously, it’s separability that
you have to give up.
- Wayne Myrvold
Tim Maudlin, a philosopher at New York University, says that Myrvold is one of the few people who appreciate the subtle implications of entanglement with its correlations between objects separated by long distances. However, he does not think that focusing on non-separability will be enough to create a local theory—one that does not seem to violate the speed of light—that also fits with quantum observations.

"If you believe that those correlations are correctly predicted by quantum mechanics then you are stuck with non-locality," says Maudlin. "The deal is not about how do I get around it, but how do I deal with it and work it into my physics in a clearer way."

Bedingham, who last year won FQXi’s Most Courageous Postdoc prize, has his own strategy for bringing quantum mechanics into line with relativity. In this model, the two entangled particles are on two unique, but interacting, hyperspaces. When one particle is observed, its wavefunction collapses sending out a ripple in that hyperspace. The second particle’s properties change when that ripple effect is felt on the adjacent hyperspace. (Read our Q&A with Daniel Bedingham for more details.)

At present, it is difficult to think of a test that could discriminate between theories of wavefunction collapse. Myrvold notes that arguments about these issues date back to the birth of quantum mechanics, with little resolution. "It might look like people are just going around in circles and getting nowhere," he admits. "But even if we haven’t reached consensus, we have a much better appreciation for what the viable options are and how to think about them."

Comment on this Article

Please read the important Introduction that governs your participation in this community. Inappropriate language will not be tolerated and posts containing such language will be deleted. Otherwise, this is a free speech Forum and all are welcome!
  • Please enter the text of your post, then click the "Submit New Post" button below. You may also optionally add file attachments below before submitting your edits.

  • HTML tags are not permitted in posts, and will automatically be stripped out. Links to other web sites are permitted. For instructions on how to add links, please read the link help page.

  • You may use superscript (10100) and subscript (A2) using [sup]...[/sup] and [sub]...[/sub] tags.

  • You may use bold (important) and italics (emphasize) using [b]...[/b] and [i]...[/i] tags.

  • You may also include LateX equations into your post.

Insert LaTeX Equation [hide]

LaTeX equations may be displayed in FQXi Forum posts by including them within [equation]...[/equation] tags. You may type your equation directly into your post, or use the LaTeX Equation Preview feature below to see how your equation will render (this is recommended).

For more help on LaTeX, please see the LaTeX Project Home Page.

LaTeX Equation Preview



preview equation
clear equation
insert equation into post at cursor


Your name: (optional)



Important: In order to combat spam, please select the letter in this menu between 'M' and 'O':




Recent Comments


I left out a couple of lines in the middle of the last paragraph of my post. It should read -

"... anticlockwise flow in a second 2D Mobius. These combine 1) via the infinitely long transcendental and irrational numbers, and 2) via bosons being ultimately composed of 1’s and 0’s depicting pi, e, √2 etc.; and fermions being given mass by bosons interacting in matter particles’ “wave packets”. They form a four-dimensional Klein bottle which is in fact one of the...


The first part of this comment concerns the equation "H(subscript u) = (BEc)(superscript e infinity), or 1 = 1(superscript infinity)" - this equation looks like the one physicists are hoping will be printed on T-shirts in the middle of this century as a description of the Universe.

H is for the Hamiltonian, representing the total energy of a quantum mechanical system. The subscript u stands for “universe” and Hu means the universe operates quantum mechanically (quantum effects...


I have documented the experiment you requested to discriminate theories of wave function collapse. The experiments demonstrate failure of the probabilistic collapse of the wave function. Starting with singly emitted gamma-rays in a beam-split coincidence test, the gamma detection should occur at one detector or the other, but not both, according to Quantum Mechanics. My coincidence rates greatly exceed chance, contradict QM, and answer many questions. Also, I performed a similar beam...

read all article comments

Please enter your e-mail address:
Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.