
Stanford University
Co-Investigators
Leonard Susskind, Stanford University
Project Title
Complexity, Black Holes, and Observers
Project Summary
There are some things that no single observer can know, even in principle. Thanks to Heisenberg's uncertainty principle, they can know both the position and momentum of a particle; thanks to the finite speed of light, they can observe two causally disconnected points. What do we make of this? You might think these are just accidental inconveniences. But the principle of complementarity -- in the first case quantum complementarity, in the second case causal complementarity -- says these are essential obstacles, required for the consistency of the laws of nature. Some paradoxical thought experiments may be resolved by restricting attention to only that which is actually observable. In this proposal, I explore a third, more radical, proposed complementarity principle. Some computations are easy, but some computations are hard. If the computation required to exhibit a would-be inconsistency in the laws of physics is sufficiently complex as to be impossible without dramatically transforming the system under study, perhaps that is reason enough to say that there is no inconsistency. I investigate moving computational complexity from an epiphenomenon to a central role in understanding the physics of the observer.
Back to List of Awardees