Equivalent? In the analogy of the math or physics results it would be a mental model in someone's brain that you can't access or verify. You just hope it's true
Open source is much more than source available though. Its about licensing.
But that doesn't map to software at all right?
I think the idea does: the point is that closed-source software isn't useful for anyone else than the (copyright)owner. In scientific standards, that is. Similar to esoteric and cryptic theories that resist accessible explanations.