Tag Archives: Bell’s Theorem

August 27, 2021

BB #75: Gloves and Shoes

Speaking of Bell tests, I’ve noticed that science writers often struggle to find a good metaphor that illustrates just what’s so weird about the correlation between entangled particles. Bell tests are complex, and because they squat in the middle of quantum weirdness, they’re hard to explain in any classical terms.

I thought I had the beginnings of a good metaphor, at least the classical part. But the quantum part is definitely a challenge. (All the more so because I’m still not entirely clear on the deep details of Bell’s theorem myself.)

Worse, I think my metaphor fails the ping-pong ball test.

35 Comments | tags: Bell's Theorem, particles, quantum mechanics | posted in Brain Bubble, Physics

August 26, 2021

QM 101: Fun with Photons

By Wyrd Smythe

Last time I explored the quantum spin of photons, which manifests as the polarization of light. (Note that all forms of light can be polarized. That includes radio waves, microwaves, IR, UV, x-rays, and gamma rays. Spin — polarization — is a fundamental property of photons.)

I left off with some simple experiments that demonstrated the basic behavior of polarized light. They were simple enough to be done at home with pairs of sunglasses, yet they demonstrate the counter-intuitive nature of quantum mechanics.

Here I’ll dig more into those and other experiments.

9 Comments | tags: Bell's Theorem, photons, QM101, quantum mechanics | posted in Physics

August 25, 2021

QM 101: Photon Spin

By Wyrd Smythe

Earlier in this QM-101 series I posted about quantum spin. That post looked at spin 1/2 particles, such as electrons (and silver atoms). This post looks at spin in photons, which are spin 1 particles. (Bell tests have used both spin types.) In photons, spin manifests as polarization.

Photon spin connects the Bloch sphere to the Poincaré sphere — an optics version designed to represent different polarization states. Both involve a two-state system (a qubit) where system state is a superposition of two basis states.

Incidentally, photon polarization reflects light’s wave-particle duality.

7 Comments | tags: Bell's Theorem, photons, QM101, quantum spin, wave-function, wave-particle duality | posted in Physics

December 12, 2014

Reality IS Virtual (probably)!

By Wyrd Smythe

virtual reality One of the things I mentioned in my recent Material Disbelief post was that, if you accept everything physics has discovered in the last 100 years or so — and if you believe in philosophical materialism — you are faced with the very strong possibility that all of reality is some sort of simulation or machine process.

Not only does all the evidence, as well as some basic logic, seem to point in that direction, but as a model of reality it provides easy answers to many of the conundrums of modern physics (e.g. Einstein’s “spooky action at a distance” and some basic questions regarding the Big Bang).

Today I want to lay out the details of the arguments for this.

28 Comments | tags: Albert Einstein, Bell's Theorem, DisneyQuest, DNA, EPR paper, Leopold Kronecker, materialism, metaphysics, Philosophical materialism, physicalism, reality, simulations, virtual reality, Zeno's paradoxes | posted in Physics