unitarily

For the system under investigation this works, it evolves unitarily until measured, then the wave function collapses non-unitarily.

This is a conflict, the combined system can not evolve unitarily and also have some subsystem, the system under investigation, evolve non-unitarily, i.e.

Does this describe how solar thermal infrared heat works between the sun and the earth, or only after unitarily transforming optics like mirrors and concentrators?

But any measurement device is also a quantum system and therefore the combined system should also evolve unitarily.

The combined system of system under investigation and measurement device however is never measured, therefore must evolve unitarily.

Wave function collapse due to measurements is not real, the wave function evolves unitarily all the time.

This change is non-unitary and therefore incompatible with the Schrödinger equation which tells us that quantum systems evolve unitarily.

Assume you've got a routine for unitarily diagonalising a self-adjoint matrix with entries in the complex numbers.

The postulates are roughly quantum system evolve unitarily except when they are measured, then a non-unitary wave function collapse happens.

You can just unitarily evolve the system for as long as you wish/can compute for.

Quantum systems evolve unitarily, measurement devices collapse the wave function which is not unitary.

It's well known that a quantum system continues to evolve unitarily (deterministically) via the propagation operator regardless of whether any subsystems have collapsed.

The claim in that phrase of the article is that a "unit test" was originally supposed to mean "a test that runs unitarily, by itself".

I guess “best low rank approximation under unitarily invariant norms“ doesn’t mean much to eyeballs though.

Why not say “we have a unit vector in C^n evolving unitarily” (Where C^n is n-tuples of complex number)?

You don’t have to believe in anything supernatural or mysterious to recognize there is a clear inconsistency here with “quantum systems sometimes evolve unitarily”.