RT Journal Article T1 Extracting Dynamical Equations from Experimental Data is NP Hard A1 Cubitt, Toby S. A1 Eisert, Jens A1 Wolf, Michael M. AB The behavior of any physical system is governed by its underlying dynamical equations. Much of physics is concerned with discovering these dynamical equations and understanding their consequences. In this Letter, we show that, remarkably, identifying the underlying dynamical equation from any amount of experimental data, however precise, is a provably computationally hard problem (it is NP hard), both for classical and quantum mechanical systems. As a by-product of this work, we give complexity-theoretic answers to both the quantum and classical embedding problems, two long-standing open problems in mathematics (the classical problem, in particular, dating back over 70 years). PB American Physical Society SN 0031-9007 YR 2012 FD 2012-03-22 LK https://hdl.handle.net/20.500.14352/44447 UL https://hdl.handle.net/20.500.14352/44447 LA eng NO Comunidad de Madrid NO Ministerio de Educación y Ciencia NO Ministerio de Ciencia e Innovación (MICINN) NO Unión Europea. FP7 NO Unión Europea NO BMBF NO Danish Research Council DS Docta Complutense RD 2 may 2024