I think it's an interesting question, it got me thinking a little bit (ianap). If you break down thinks at the microscopic level, angular momentum seems to not

I think it's an interesting question, it got me thinking a little bit (ianap). If you break down thinks at the microscopic level, angular momentum seems to not be a thing in itself, but rather a combination of momentum and some force that keeps things from going away from a center, like gravity in the case of interstellar gas, or chemical bonds in the case of a solid object. So what gets transferred in the end is momentum of all the gas particles that get assimilated in the neutron star. That begs the question, what is momentum? I don't really know, I guess it's a fundamental property of matter that can't get broken down further.