Matt O'Dowd is starting to look at a question I find extremely interesting. What is the ontology of spacetime? A lot of physicists have begun to wonder whether its fundamental, or emergent from something else. Quantum entanglement is the one I'm familiar with, but I understand there are other possibilities. (This video is 26 minutes … Continue reading Is the question whether spacetime is real, or whether it’s fundamental?

# Tag: Physics

# It’s not looking good for objective collapse theories

As noted in the previous post, quantum mechanics is weird. If we try to have a realist understanding of what's happening, it forces bizarre choices about which aspects of common sense reality we throw under the buss. The central mystery is the wave function collapse. Quantum particles move like waves, mathematically described by the wave … Continue reading It’s not looking good for objective collapse theories

# It pays to remember that reality is absurd

Last week the Nobel Prize in Physics was awarded to Alain Aspect, John F. Clauser, and Aton Zeilinger, for their work in testing quantum entanglement, essentially validating that quantum mechanics is correct about the phenomenon, and eliminating, or at least profoundly minimizing, any possible loopholes. https://twitter.com/NobelPrize/status/1577234271546200064 Of course this set off a lot of physicists … Continue reading It pays to remember that reality is absurd

# A way to understand quantum computing

The other day I shared a video on quantum computing, which I thought was informative, but the feedback I received is that it wasn't for anyone not already versed in the subject. Since I once struggled to understand this subject myself, I tried to think of a way of describing it that would actually help. … Continue reading A way to understand quantum computing

# Decoded: How does a quantum computer work?

This Scientific American video, shared by Aeon, is pretty good if you're looking for a quick basic primer on quantum computing. It's short, less than nine minutes. Although I do have a beef which I'll discuss below. https://www.youtube.com/watch?v=uLnGp1WTNFQ Decoded: How Does a Quantum Computer Work? The beef, which is pretty common with popular explanations of … Continue reading Decoded: How does a quantum computer work?

# Many-worlds and Bell’s theorem

Sean Carroll's February AMA episode is up on his podcast. As usual, there were questions about the Everett many-worlds interpretation of quantum mechanics (which I did a new primer on a few weeks ago). This time, there was a question related to the correlated outcomes in measurements of entangled particles that are separated by vast … Continue reading Many-worlds and Bell’s theorem

# The entanglements and many worlds of SchrĂ¶dinger’s cat

I recently had a conversation with someone, spurred by the last post, that led to yet another description of the Everett many-worlds interpretation of quantum mechanics, which I think is worth putting in a post. It approaches the interpretation from a different angle than I've used before. As mentioned last time, the central mystery of … Continue reading The entanglements and many worlds of SchrĂ¶dinger’s cat

# The benefits of wave function realism?

The central mystery of quantum mechanics is that quantum particles move like waves but hit and leave effects like localized particles. This is true of elementary particles, atoms, molecules, and increasingly larger objects, possibly macroscopic ones. It's even true of collections of entangled particles, no matter how separated the particles may have become. People have … Continue reading The benefits of wave function realism?

# Superdeterminism and the quandaries of quantum mechanics

Last week, Sabine Hossenfelder did a video and post which was interesting (if a bit of a rant at times at strawmen) in which she argued for a little considered possibility in quantum mechanics: superdeterminism. In 1935, Einstein and collaborators published the famous EPR paradox paper, in which they pointed out that particles that were … Continue reading Superdeterminism and the quandaries of quantum mechanics

# Reconciling the disorder definition of entropy

In last week's post on entropy and information, I started off complaining about the most common definition of entropy as disorder or disorganization. One of the nice things about blogging is you often learn something in the subsequent discussion. My chief complaint about the disorder definition was that it's value-laden. I asked: disordered according to … Continue reading Reconciling the disorder definition of entropy