Ships are capable of FTL warp and relativistic speed flying. In order for a ship to intercept other ship at high non-FTL speed, it needs a mechanism that will enable it to slow down the other ship.
Most space battles will ensue after the speed-limit weapon is deployed, creating a region of space where ships are experiencing drag and will make them harder to escape and accelerate virtually to speed of light.
Things I'm looking for:
- A missile payload that will disperse high friction gas that have will linger in the area(fast initial dispersion, but slows down eventually).
- A device that increases the relativistic effect, so less acceleration due to increased mass when traveling at high velocity.
Things I'm NOT looking for:
- Gravity tether or tractor beams. It needs to be an area of effect, causing multiple ships to slow down.
UPDATE: Thank you for all your contributions!
To clarify, the weapon is not to disable FTL warp, as in my setting, it requires substantial preparation to make an FTL journey, so no emergency jump.
The weapon is needed to keep ships from accelerating constantly achieving relativistic speed and escaping. Otherwise, there will be no practical way to catch smaller faster accelerating ships. Also, I didn't want the space battle happen at lower velocities, somewhere between real space battle and atmospheric dog fight.