80,000 Hours Podcast

#115 – David Wallace on the many-worlds theory of quantum mechanics and its implications

Nov 12, 2021
In this engaging discussion, guest David Wallace, a leading philosopher of physics from the University of Pittsburgh, delves into the many-worlds theory of quantum mechanics. He explores how alternate realities emerge from quantum choices, challenging our understanding of existence. Wallace also tackles the philosophical implications of decision-making in a multiverse. The conversation touches on ethical considerations in branching realities and the complexities of reconciling quantum mechanics with classical physics. Prepare for a mind-bending journey through the fabric of reality!
Ask episode
AI Snips
Chapters
Transcript
Episode notes
INSIGHT

Quantum Superposition

  • In quantum mechanics, objects can possess multiple properties simultaneously, like being in two places or spinning two ways at once.
  • This multiplicity scales up from the microscopic level, affecting larger systems and leading to counterintuitive phenomena.
ANECDOTE

Two-Slit Experiment

  • The two-slit experiment demonstrates interference, where an electron going through two slits simultaneously interferes with itself.
  • Even single electrons exhibit interference, as if multiple versions of the electron traverse different paths.
INSIGHT

The Measurement Problem

  • Quantum mechanics needs interpretation because of macroscopic superpositions, like Schrödinger's cat being both alive and dead.
  • The theory uses an ad hoc rule to treat superpositions as probabilities at the macroscopic level, which is problematic.
Get the Snipd Podcast app to discover more snips from this episode
Get the app