Many-worlds and Bell’s theorem

Schrodinger's cat in many worlds

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 Schrödinger’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 Schrödinger’s cat

The benefits of wave function realism?

Hydrogen wave function plots

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

Carlo Rovelli’s Helgoland

I've posted a lot over the years on interpretations of quantum mechanics. My writing has tended to focus on comparing the big three: Copenhagen, pilot-wave, and many-worlds. But there are a lot of others. One that has been gaining converts among physicists and others is Carlo Rovelli's relational quantum mechanics (RQM) interpretation. This is an … Continue reading Carlo Rovelli’s Helgoland

The measurement problem, Copenhagen, pilot-wave, and many worlds

With quantum physics, we have a situation where a quantum object, such as a photon, electron, atom or similar scale entity, acts like a wave, spreading out in a superposition, until we look at it (by measuring it in some manner), then it behaves like a particle.  This is known as the measurement problem. Now, … Continue reading The measurement problem, Copenhagen, pilot-wave, and many worlds