Does this tweet have any physical interpretation?

• I
accdd
I read this tweet (I omit the author for privacy), and my curiosity led me to ask questions::
Any optimization problem is equivalent to a convex (linear) one (but infinite dimensional…). The key do perform global optimization using Lasserre’s relaxation via the problem of moment (aka sum-of-square relaxation). https://en.wikipedia.org/wiki/Sum-of-squares_optimization…

First, I ask if this is a true statement.
Secondly: does this have any relation to physics? Lagrangian mechanics is an optimization problem, and quantum mechanics has to do with probability and infinite-dimensional spaces.