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Since: relativistic = a significant fraction of light speed

We'll use 1% as the bottom threshold of relativistic, just to be generous.

A 1 gram bullet accelerated to 1% of the speed of light (c = 300,000km/s) would have a recoil of 3,000,000 gram meters per second. Say that an average grown man is about 100kg (220 pounds). Firing such a weapon would throw that man back at a speed of 30 meters per second (98 feet per second).

Ok, now the man-portable gauss rifles in Eraser were pretty wicked, but can we really say that they used "relativistic velocities"?

As I recall, one of the characters in the movie said they fired bullets at "nearly the speed of light." In the original version of the article I wrote that Eraser's guns were unrealistic but someone removed that comment, presumably considering it to be POV. I didn't want to get into an argument over it at the time, but if you want to put it back in then I'll certainly support that. :) Bryan

Since the math doesn't lie, yes, I think that we should keep it in. Note that in my comment, above, I didn't discuss what would happen to someone who tried to hold on to a weapon with that much recoil or the fact that 1 gram would not be a very heavy bullet (a heavier bullet would have MORE recoil) or the fact that a bullet traveling that fast would have severe problems with atmospheric friction or the fact that accelerating a bullet to that kind of velocity would require HUGE amounts of energy. Donald

The recoil can, in any case, be negated or lessened by using a countershot. See Armbrust for a modern example of the system. Of course it can be debated whether the gun becomes safer or not when there are relative speed items issuing from BOTH ends of it... :) Naturally a countershot could be much heavier, to lessen it's speed, and disperse in a manner similar to Armbrust's plastic shreddings. A smart gun (hey, it's scifi) might even try to make a best guess as to which direction to vent the countershot in order to prevent damage to anything valuable nearby.

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A similar article has appeared over at Relativistic bomb. Merge? -- DavidHouse.

I'd agree. I've added the merge notices, as per Wikipedia:Duplicate_articles. CS Miller 18:49, August 11, 2005 (UTC)

[edit] Removing Halo ref

Gauss/Rail weapons are their own class of weapon, and don't need to be inserted here. Part of the point of the RKV is that it's usually a genocidal planet-destroyer, not a precision tactical weapon like, for example, the MAC guns in Halo. Also, part of the idea is generally that it is a kill VEHICLE, as in a ship designed to kill using relativistic effects, and not just a ship/weapon that happens to fire things really fast. The "relativistic bomb" idea is closer to this article's intent- this weapon is basically an evolution of the nuke. 209.153.128.248 14:48, 3 January 2007 (UTC)

Saying that relativistic bomb is an evolution of a nuke is a bit of a stretch. You do not need any warhead if you have a really fast projectile. When RKV's speed crosses 0.8c barrier, it actually becomes MORE deadly than if it's mass was pure antimatter. In "Killing Star" novel referred in the article aliens that destroyed Earth used simple slugs about 10 tons of mass at 92% cee. With this setup they packed about twice more punch than ten tons of antimatter, and without its shortcomings. So I agree with you in that it's generally a strategical weapon, but I'd be more careful with words. --Khathi 10:20, 10 October 2007 (UTC)

[edit] =The speed when E(kinetic)m(proper)c^2 = e(kinetic)

(A fairly simple, if beefy calculation.) I think that it would be nice to mention it in the text. I'm too drunk and busy to calculate it at the moment.--UDoWs 02:05, 29 July 2007 (UTC)

[edit] Lensman series

I cut the following from the examples in fiction:

One of the earliest, if not the earliest examples come from E. E. "Doc" Smith's Lensman series. Here whole planets are brought to opposing vectors at relativistic speeds, to squash target planets between them.

This weapon, which the Lensmen called the "nutcracker", is accurately but misleadingly described in the second sentence. The "nutcracker" was made possible by Smith's plot device used to permit FTL starships without breaking the rules of Einsteinian physics: the "inertialess drive" which can turn off the inertia of any mass. When the drive is deactivated, the mass moves with the same momentum and direction it had just before the drive was activated. Thus, the "nutcracker": the Galactic Patrol locates two planets with opposite vectors, removes their inertia, moves them to either side of the target planet, and restores their inertia; the planets resume their motion but are now on a collision course with the target in the path of both. Although the planets are moved from system to system at relativistic or faster speeds, in Smith's version of physics their essential masslessness means they are not subject to relativistic effects, and they are returned to conventional speeds when unleashed as a weapon. Their high kinetic energy is due to large mass rather than large velocity, so they do not fit the definition of "relativistic kill vehicle" as I understand it. --Kineticman (talk) 07:07, 26 December 2007 (UTC)