Journal of High Energy Physics

, 2018:39 | Cite as

Complexity is simple!

Open Access
Regular Article - Theoretical Physics


In this note we investigate the role of Lloyd’s computational bound in holographic complexity. Our goal is to translate the assumptions behind Lloyd’s proof into the bulk language. In particular, we discuss the distinction between orthogonalizing and ‘simple’ gates and argue that these notions are useful for diagnosing holographic complexity. We show that large black holes constructed from series circuits necessarily employ simple gates, and thus do not satisfy Lloyd’s assumptions. We also estimate the degree of parallel processing required in this case for elementary gates to orthogonalize. Finally, we show that for small black holes at fixed chemical potential, the orthogonalization condition is satisfied near the phase transition, supporting a possible argument for the Weak Gravity Conjecture first advocated in [1].


AdS-CFT Correspondence Black Holes in String Theory 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Institute for Theoretical Physics AmsterdamUniversity of AmsterdamAmsterdamThe Netherlands
  2. 2.Institute for Theoretical Physics and Center for Extreme Matter and Emergent PhenomenaUtrecht UniversityUtrechtThe Netherlands

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