Canon tells us that photon torpedoes are essentially projectile weapons, fast-moving missiles that can move at warp speed or very high sublight speed and then explode when they hit a target. This has been basically the case for photon torpedoes since we first saw the torpedo room in Wrath of Khan and it's been more or less consistent ever since.
But I've spent a couple of years grappling with how torpedoes are ACTUALLY USED: how they're targeted, how they're launched, the kinds of things that go wrong with them, the kinds of things they can be programmed to do. More and more, I am convinced that photon torpedoes simply do not make sense as projectile weapons.
That, inevitably, leaves me with the question I now put it to my fellow tech heads: given everything we've seen, if photon torpedoes aren't physical "missiles," then what else COULD they be?