The Giants Shoulder

#101 Meet The Physicist Who Believes Time Doesn’t Exist

Mar 9, 2026
Guest
Julian Barbour
Dr. Julian Barbour, independent theoretical physicist and author who argues time is not fundamental. He discusses Shape Dynamics and how sequences of shapes can mimic change. He explains the Wheeler–DeWitt 'frozen' universe, the idea of time capsules that create the appearance of a past, and how consciousness might weave motion and color into a static mathematical world.
Ask episode
AI Snips
Chapters
Books
Transcript
Episode notes
ANECDOTE

Dirac Article Triggered A Lifetime Quest

  • A 1963 Scientific American article by Paul Dirac sparked Julian Barbour's lifelong question about time after reading it on a mountain trip.
  • Dirac argued four-dimensional spacetime contains redundant structure and simultaneity should be restored, which pushed Barbour to investigate time.
INSIGHT

Wheeler DeWitt Implies A Frozen Universe

  • The Wheeler–DeWitt equation yields stationary probabilities for whole-universe configurations, implying no fundamental time evolution.
  • Barbour frames this as probabilities for instantaneous shapes, motivating his shape-space ontology and 'time capsules'.
INSIGHT

Shape Space Replaces Absolute Size And Time

  • Shape space removes absolute scale so three particles are represented by triangle shapes only, and dynamics becomes succession of shapes not evolution in time.
  • Direction of time is nominal; sequences of shapes can be run forwards or backwards like film stills.
Get the Snipd Podcast app to discover more snips from this episode
Get the app