What is a quantum torpedo?

Question

I was watching Star Trek DS9 and they were using someting called a quantun torpedos.

In theory, what would that be?

And why would it be better than photon torpedos and phasers?

Answer 1

Quantum torpedoes were considered an upgrade to the standard photon torpedo. Deployment began throughout Starfleet in the beginning of 2371. In the same year, the mirror universe Terran Rebellion obtained quantum torpedo technology by stealing it from the Federation.

I suppose it would be better because it was the upgrade.

Answer 2

the quantum torpedo was a tactical weapon used by at least the federation starfleet, the terran rebellion and the cardassion union.

Answer 3

The quantum torpedo was a tactical weapon used by at least the Federation Starfleet, the Terran Rebellion and the Cardassian Union.

Federation quantum torpedoes apparently use the standard photon torpedo casing. (DS9: "Valiant")

Nog modifies unspecified torpedoes with photon torpedo casings in this episode. When they are fired the effect is identical to the quantum torpedo. A line in DS9: "For the Uniform" suggests the quantum torpedo might be some type of plasma torpedo as plasma warheads on quantum torpedoes 3 and 4 were mentioned in the episode.

Even a direct hit from a quantum torpedo might not destroy solid neutronium. (DS9: "To the Death")