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Fast optimization algorithms and the cosmological constant



Stephen P. Jordan, Ning Bao, Brad Lackey, Raphael Bousso


Denef and Douglas have observed that in certain landscape models the problem of finding small values of the cosmological constant is a large instance of an NP-hard problem. The number of elementary operations (quantum gates) needed to solve this problem by brute force search exceeds the estimated computational capacity of the observable universe. Here we describe a way out of this puzzling circumstance: despite being NP-hard, the problem of finding a small cosmological constant can be attacked by more sophisticated algorithms whose performance vastly exceeds brute force search. In fact, in some parameter regimes the average-case complexity is polynomial. We demonstrate this by explicitly finding a cosmological constant of order 10^−120 in a randomly generated 10^9-dimensional ADK landscape.
Physical Review A


complexity theory, cosmology


Jordan, S. , Bao, N. , Lackey, B. and Bousso, R. (2017), Fast optimization algorithms and the cosmological constant, Physical Review A (Accessed June 19, 2024)


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Created November 1, 2017, Updated August 1, 2019