Symmetrization methods
In mathematics the symmetrization methods are algorithms of transforming a set A ⊂ R n {\displaystyle A\subset \mathbb {R} ^{n}} to a ball B ⊂ R n {\displaystyle B\subset \mathbb {R} ^{n}} with equal volume vol ( B ) = vol ( A ) {\displaystyle \operatorname {vol} (B)=\operatorname {vol} (A)} and centered at the origin. B is called the symmetrized version of A, usually denoted A ∗ {\displaystyle A^{*}} .