Quantum Foundations Podcast A new theory of quantum & spacetime with Prof. Gerard Milburn
Mar 17, 2026
Gerard Milburn, a theoretical physicist specializing in quantum optics and foundations, proposes radical ideas at the quantum–gravity interface. He explores whether unmeasured pure quantum states fail to source gravity. Topics include Bell tests and spacetime labeling, gravity’s role in assigning coordinates, implications for black holes and the Big Bang, and possible limits on large-scale quantum technologies.
AI Snips
Chapters
Transcript
Episode notes
How Milburn Entered Quantum Optics
- Milburn entered quantum optics after hearing Dan Walls speak as an undergraduate and shifted from practical physics to a PhD in quantum optics.
- That choice led him into quantum foundations, quantum computing ideas and lifelong collaborations with experimentalists.
Bell Correlations Don't Need Space Time
- Bell-test correlations don't require a space-time story because detector coordinates are irrelevant to the quantum probabilities given by the Born rule.
- Milburn shows the same correlations appear using retroreflectors so detector time/place labels can't underwrite nonlocal narratives.
Detectors Gain Space Time Labels Through Gravity
- Detector macroscopicity and spacetime labels enter experiments only when we assign coordinates via gravity, not in the quantum formalism.
- Milburn emphasizes the Born rule gives probabilities without coordinates; gravity explains where and when macroscopic clicks occur.