The Moreau-Yosida Regularization: Difference between revisions

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==Motivation==
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==Definitions==
==Definitions==
Let <math>(X,d)</math> be a metric space. A function <math>g : X \to (-\infty,+\infty]</math> is said to be '''proper''' if it is not identically equal to <math>+\infty</math>, that is, if there exists <math>x \in X</math> such that <math>g(x) < +\infty</math>.
Given a function <math>g : X \to (-\infty,+\infty]</math>, its '''Moreau-Yosida regularization''' <math>g_k : X \to (-\infty,+\infty]</math> is given by


:<math>g_k(x) := \inf\limits_{y \in X} \left[ g(y) + k d(x,y) \right],</math>


where <math>k \geq 0</math>.


==Examples==
==Examples==
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==References==
Possible list of references, will fix accordingly


==References==
Bauschke-Combette Ch 12.<ref name="BC" />; Santambrogio (6)<ref name="S" />; Ambrosio-Gigli-Savare (59-61)<ref name="AGS" />
<references>
<references>
 
<ref name="BC">Bauschke, Heinz H. and Patrick L. Combettes. ''Convex Analysis and Monotone Operator Theory in Hilbert Spaces, 2nd Ed.'' Ch. 12. Springer, 2017.</ref>
<ref name="S">Santambrogio, Filippo. ''Optimal Transport for Applied Mathematicians: Calculus of Variations, PDEs, and Modeling'' Ch. 1.1. Birkhäuser, 2015.</ref>
<ref name="AGS">Ambrosio, Luigi, Nicola Gigli, and Giuseppe Savaré. ''Gradient Flows in Metric Spaces and in the Space of Probability Measures.'' Ch. 3.1. Birkhäuser, 2005.</ref>


</references>
</references>

Revision as of 20:40, 21 January 2022

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Motivation

(to be filled in)


Definitions

Let be a metric space. A function is said to be proper if it is not identically equal to , that is, if there exists such that .

Given a function , its Moreau-Yosida regularization is given by

where .

Examples

(to be filled in, hopefully with pictures!)



References

Possible list of references, will fix accordingly

Bauschke-Combette Ch 12.[1]; Santambrogio (6)[2]; Ambrosio-Gigli-Savare (59-61)[3]

  1. Bauschke, Heinz H. and Patrick L. Combettes. Convex Analysis and Monotone Operator Theory in Hilbert Spaces, 2nd Ed. Ch. 12. Springer, 2017.
  2. Santambrogio, Filippo. Optimal Transport for Applied Mathematicians: Calculus of Variations, PDEs, and Modeling Ch. 1.1. Birkhäuser, 2015.
  3. Ambrosio, Luigi, Nicola Gigli, and Giuseppe Savaré. Gradient Flows in Metric Spaces and in the Space of Probability Measures. Ch. 3.1. Birkhäuser, 2005.