extremal

American  

[ik-stree-muhl] / ɪkˈstri məl /

adjective

Mathematics.

1. of or relating to an extremum or the calculation of extrema.

   an extremal problem.

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extremal British  

/ ɪkˈstriːməl /

noun

1. maths logic the clause in a recursive definition that specifies that no items other than those generated by the stated rules fall within the definition, as in 1 is an integer, if n is an integer so is n+1, and nothing else is

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Etymology

Origin of extremal

First recorded in 1400–50; late Middle English. extremum, -al ¹

Example Sentences

Whereas such "extremal" black holes have been hypothesized for decades, until now no one had discovered a realistic process by which such oddities actually could have formed in our universe.

From Science Daily • Jun. 6, 2024

The Ryu-Takayanagi result showed that the area of the extremal surface of a black hole in the AdS is related to the entanglement entropy of the quantum system in the CFT.

From Scientific American • Nov. 30, 2022

In 2014, Engelhardt and Aron Wall figured out a way to calculate the extremal surface area of a black hole that is subject to the kind of quantum corrections that cause Hawking radiation.

From Scientific American • Nov. 30, 2022

As a black hole evaporates in AdS, the area of its extremal surface changes.

From Scientific American • Nov. 30, 2022

She tells stories that, the translator Anna Summers writes, Russians would call extremal, that is, “too extreme for casual tale-swapping, suitable only for furtive whispering.”

From The New Yorker • Oct. 2, 2014