Dissection into orthoschemes

Unsolved problem in mathematics
Can every simplex be dissected into a bounded number of orthoschemes?

In geometry, it is an unsolved conjecture of Hugo Hadwiger that every simplex can be dissected into orthoschemes, using a number of orthoschemes bounded by a function of the dimension of the simplex. If true, then more generally every convex polytope could be dissected into orthoschemes.