In
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
, Vitale's random Brunn–Minkowski inequality is a
theorem due to
Richard Vitale that generalizes the classical
Brunn–Minkowski inequality for
compact subsets of ''n''-
dimensional
Euclidean space R
''n'' to
random compact sets.
Statement of the inequality
Let ''X'' be a random compact set in R
''n''; that is, a
Borel–
measurable function
In mathematics and in particular measure theory, a measurable function is a function between the underlying sets of two measurable spaces that preserves the structure of the spaces: the preimage of any measurable set is measurable. This is in di ...
from some
probability space (Ω, Σ, Pr) to the space of
non-empty,
compact subset
In mathematics, Set (mathematics), set ''A'' is a subset of a set ''B'' if all Element (mathematics), elements of ''A'' are also elements of ''B''; ''B'' is then a superset of ''A''. It is possible for ''A'' and ''B'' to be equal; if they are ...
s of R
''n'' equipped with the
Hausdorff metric. A
random vector ''V'' : Ω → R
''n'' is called a selection of ''X'' if Pr(''V'' ∈ ''X'') = 1. If ''K'' is a non-empty, compact subset of R
''n'', let
:
and define the set-valued
expectation
Expectation or Expectations may refer to:
Science
* Expectation (epistemic)
* Expected value, in mathematical probability theory
* Expectation value (quantum mechanics)
* Expectation–maximization algorithm, in statistics
Music
* ''Expectation' ...
E
'X''of ''X'' to be
:
Note that E
'X''is a subset of R
''n''. In this notation, Vitale's random Brunn–Minkowski inequality is that, for any random compact set ''X'' with
,
:
where "
" denotes ''n''-dimensional
Lebesgue measure
In measure theory, a branch of mathematics, the Lebesgue measure, named after French mathematician Henri Lebesgue, is the standard way of assigning a measure to subsets of ''n''-dimensional Euclidean space. For ''n'' = 1, 2, or 3, it coincides wit ...
.
Relationship to the Brunn–Minkowski inequality
If ''X'' takes the values (non-empty, compact sets) ''K'' and ''L'' with probabilities 1 − ''λ'' and ''λ'' respectively, then Vitale's random Brunn–Minkowski inequality is simply the original Brunn–Minkowski inequality for compact sets.
References
*
*
{{DEFAULTSORT:Vitale's random Brunn-Minkowski inequality
Probabilistic inequalities
Theorems in measure theory