This is an overview of the 4th generation of nuclear weapons outlined in the report, Fourth Generation Nuclear Weapons: Military effectiveness and collateral effects, condensed into an easy to digest video. Full report click here, http://arxiv.org/abs/physics/0510071v5
Q: In a nutshell what is a Fourth Generation Nuclear Weapon (FGNW)? A: It is a nuclear fusion weapon that doesn’t use a fission trigger. The most feasible method to trigger fusion in a FGNW is to use microscopic amounts of anti-matter.
Q: What advantages do FGNWs have over conventional nukes? A: They are “clean” (radioactive fallout negligible, about on par with conventional depleted uranium weapons that are already in use), they are very small (potentially can fit in your pocket), and fill in the “yield gap” between the most powerful conventional weapons and the lowest yield conventional nukes.
Q: Will FGNWs really be more politically acceptable to use in actual combat? A: Who knows? Only time can tell for certain, but their “radioactive cleanness” is a compelling argument in favor for it.
Q: What would be the TNT equivalent of a FGNW be? A: A 3 gram pellet of fusion fuel would release around 302 gigajoules of energy (about 72 tons of TNT), so around that.
Q: How much antimatter is needed to catalyze a single FGNW? A: A 3 gram pellet of fusion fuel would need 1×10^11 antiprotons to catalyze nuclear fusion
Q: Isn’t carrying antimatter dangerous? What would happen if containment failed? A: The quantity of antimatter is extremely small. 1×10^11 antiprotons would release the equivalent of about 6 milligrams of TNT, that’s less than a firecracker. However the energy would be released in the form of ionizing radiation so it would be a radiological hazard if containment failed.
Q: Wouldn’t failure of antimatter containment result in the FGNW detonating? A: No, nuclear fusion requires very precise injection of antimatter to catalyze fusion. Failure of containment would not result in the precise injection of antimatter to the fusion fuel. Added safety measures can be taken by separating the fusion fuel from the antimatter containment until the weapon is ready to be armed.
Q: If you accidentally drop it, wouldn’t containment fail? A: These weapons are intended to be incredibly rugged with one of their applications being bunker busters. They contain little to no moving parts and are “full like eggs”. The FGNW report indicates that the overall ruggedness would be far superior over conventional nuclear bunker busters so no, simply dropping it wouldn’t cause containment to fail.
Q: Wouldn’t FGNWs be attractive for nuclear terrorism? A: No, it’s easier to build conventional nuclear weapons. FGNWs require extremely large particle accelerators to manufacture the antimatter necessary for the FGNW. A terrorist who wants a suitcase nuke is better off with something like the M-388 Davy Crockett.
Q: Are FGNW a proliferation concern? A: No, see above.
Q: Why not make pure anti-matter weapons instead? A: A couple of reasons. It’s prohibitively expensive. It’s single handedly the most expensive substance in the world and incredibly difficult to make. Right now, if we took all the antimatter we produced and annihilate it, it would only be enough to power a lightbulb for a few hours. On the other hand, fusion fuel is incredibly cheap and abundant, you can literally make it from sea water as all it is are isotopes of hydrogen. But even if we had large quantities of antimatter, it’s questionable how useful it would be as a weapon on its own. It’s incredibly difficult to contain as if it touches any normal matter, it will annihilate. Containing microscopic quantities is not a problem, but macroscopic quantities are. Even if you could contain it, it would be incredibly unstable. Fusion and fission weapons fail safely, if you damage a nuclear weapon the nuclear weapon doesn’t detonate. An antimatter weapon would detonate as soon as containment fails. From a cost-benefit point of view, pure antimatter weapons do not make sense.