We don’t know that there is anything better, but given how much we don’t know it’s not unreasonable to consider that we might not have the technology to receive communications from more advanced civilizations.
I agree with you that RF is a good communication medium given what we know, I just don’t put much weight on our existing knowledge being all there is.
> Of course we don't know everything, but the discussion really ends there: we don't know what we don't know.
I think the guy I replied to asked about "theories" of alternatives, and there isn't really anything specific as far as I'm aware; there's just this vague philosophical notion that we don't know what we don't know. I don't think anyone's denying it (I certainly am not) but there is not much else to be said on the subject. Knowing that we don't know what we don't know doesn't help us make predictions about what we don't know.
Quantum entanglement does not, as far as we know, enable superluminal transmission of information. "Teleportation" is implementation-dependent and at this point entirely science fiction. If you're going to rip something apart or non-destructively scan it, and rebuild it at the other end, which is the only "realistic" theory of how it might work, you either need to transmit the bits or the bits (heh) and then you're back to the same problem of information transmission.
Of course we don't know everything, but the discussion really ends there: we don't know what we don't know.