complexity theory

American  

noun

1. the study of complex and chaotic systems and how order, pattern, and structure can arise from them.

2. the theory that processes having a large number of seemingly independent agents can spontaneously order themselves into a coherent system.

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complexity theory British  

noun

1. maths the study of complex systems, including subjects such as chaos theory and genetic algorithms

2. computing a field in theoretical computer science dealing with the resources required during computation to solve a given problem

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complexity theory Scientific  

/ kəm-plĕk′sĭ-tē /

1. See computational complexity

2. Any of various branches of mathematics, physics, computer science, and other fields, concerned with the emergence of order and structure in complex and apparently chaotic systems.

3. See also chaos

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Example Sentences

This advance was possible because the researchers identified links between the equations used in dipole models and those found in complexity theory.

From Science Daily • Jan. 5, 2026

“What’s amazing is that quantum complexity theory has been the key to the proof,” says Toby Cubitt, a quantum-information theorist at University College London.

From Nature • Jan. 15, 2020

The confluence of complexity theory, quantum information and mathematics means that there are very few researchers who say that are able to grasp all the facets of this paper.

From Nature • Jan. 15, 2020

The influence of complexity theory, consequently, has been hard to quantify, because its impacts are spread among other fields, rather than in its own cordoned-off territory.

From Slate • Jan. 19, 2016

His library on the second floor of his house in Virginia is lined with rows upon rows of works on complexity theory and military strategy.

From "Blink" by Malcolm Gladwell