HAZ-1: The arrival burst

Do not decelerate towards anything you like.

Kind: constraint · Family: HAZ (Hazards) · Last reviewed: 2026-09-12

The result

A superluminal warp bubble sweeps up particles it meets; they become "time locked" in the wall and gain extremely high energy. When the bubble drops below c, everything captured is released as a burst, and the region ahead of a ship decelerating from superluminal to subluminal speed is blasted with a concentrated beam of extremely high-energy particles. Particles picked up earlier in the trip get the larger effect

What it forbids or costs

Do not decelerate towards anything you like

Escape hatches

Decelerate far out; a route through empty space; unknown whether wall geometry can shed the load

Who it bites

Physics proposals

• VIOLATES: Alcubierre 1994: the warp drive metric. McMonigal, Lewis and O'Byrne computed on this metric that particles swept up by a superluminal bubble become time locked in the wall and are released as a high-energy burst ahead of a decelerating ship; Alcubierre's own itinerary decelerates from superluminal to rest at a distance $d \ll D$ from the destination star, which is the case they price.
• VIOLATES: Warp drives in modified gravity. McMonigal, Lewis and O'Byrne's sweeping-up and burst are kinematics of test particles on the Alcubierre metric, and in Einstein-Cartan theory test particles outside matter follow the same geodesics; the hazard is inherited unchanged.
• SILENT: Bobrick and Martire 2021: physical warp drives. Sweeping up interstellar matter is never discussed; the subluminal class avoids the superluminal burst, the superluminal classes would not
• SILENT: Fell and Heisenberg 2021: positive energy from hidden geometric structure. Swept-up matter never discussed
• SILENT: Lentz 2021: hyper-fast positive-energy solitons. Interstellar matter swept up by the wall is never discussed
• SILENT: NASA Eagleworks warp field interferometer. Never discussed
• SILENT: Natário 2002: warp drive with zero expansion. The sweeping-up of particles by a superluminal wall was computed for the Alcubierre profile; the mechanism (a wall moving faster than light with a horizon ahead) is present in every member of the class, but the burst has not been computed for the zero-expansion drive.
• SILENT: Van Den Broeck 1999: the pocket geometry. The outer bubble sweeps a femtometre-scale cross-section, so far fewer particles are caught than by a hundred-metre bubble, but any that are caught are time locked and released on deceleration as McMonigal, Lewis and O'Byrne describe; not computed for this geometry.
• SILENT: White et al. 2021: the worldline-numerics Casimir pattern. Never discussed

Fictional drives

• SILENT: Campbell's Islands of Space (1931): where the word came from. A bubble sweeps up what it meets; the novel says meteors cannot be hit because the ship is not in normal space, which is a rule about hitting, not about what the wall collects and releases on exit.
• SILENT: Death's End: curvature propulsion (Liu Cixin, 2010). A subluminal shell still sweeps up matter; the Halo's flight through interstellar dust at lightspeed is not examined for what the shell collects or releases.
• SILENT: Futurama: the Planet Express ship's dark matter engines (1999 onward). The ship stops beside planets in every episode; the burst of swept-up matter is never mentioned.
• SILENT: Star Trek: warp drive (1966 onward). Ships drop from warp beside planets and stations in every episode; the burst of swept-up particles that McMonigal, Lewis and O'Byrne price is never mentioned.
• SILENT: The Orville: quantum drive (2017 onward). Ships drop out of quantum beside planets and stations; the burst of swept-up particles is never mentioned.
• ENGAGES: Elite Dangerous: the frame shift drive (Frontier Developments, 2014). Dropping out of supercruise at speed is depicted as hazardous: emergency drops damage hull and modules, crossing an impact surface at speed forces one, and the safe disengage requires slowing first. The mechanism is not the McMonigal burst, but the constraint's shape is in the flight model.
• ENGAGES: Halo: slipspace and the Shaw-Fujikawa translight engine (2001 onward). Halo 2 shows a carrier exiting slipspace over a city and the shockwave that follows, and the wiki adds the implosion on entry in atmosphere; this is the arrival hazard on screen, in the franchise's own terms, though not the particle-release mechanism the register prices.
• ENGAGES: Mass Effect: element zero and the FTL drive (BioWare, 2007). The Codex describes what happens when the field collapses at superluminal speed: the ship snaps to sublight and the excess energy is shed as lethal Cherenkov radiation. It is the setting's own deceleration hazard, addressed on the page.
• ENGAGES: Spaceballs: ludicrous speed (1987). The emergency stop is the film's deceleration hazard: the lever is labelled never to be used, it is used, and the commander is thrown into a console. A joke, but the constraint's shape is on screen.
• ENGAGES: Star Trek: transwarp, quantum slipstream and the other beyond-warp drives. The Glenn's crew are killed on exiting the mycelial plane by a Hawking radiation firewall, and Voyager is violently ejected when the slipstream collapses; exit from faster-than-light travel is depicted as hazardous on screen in "Context Is for Kings" and "Hope and Fear". Not the McMonigal burst, but the constraint's shape.
• RULE: EVE Online: the warp drive (CCP Games, 2003). The lore has the bubble disperse automatically at a set distance from the target, and the mechanics decelerate a ship over about three astronomical units before it emerges; a stated rule that answers the deceleration hazard without naming it.
• RULE: Star Citizen: quantum drive and jump points. A subluminal bubble does not time-lock swept-up matter in the entry's sense, and the game's quantum travel has no arrival burst; interdiction pulls ships out without debris. The entry's hazard is avoided by the sublight rule rather than engaged.
• RULE: Stellaris: warp, hyperlane and wormhole (Paradox Development Studio, 2016). Warp fleets had to begin and end at the system edge and arrived at a predictable point; a stated rule with the shape of the deceleration hazard, given a strategic rather than physical reason.
• RULE: The Lensman inertialess drive (E. E. Smith, 1934 onward). The bubble-release burst does not apply, but the series has its own version of the deceleration hazard: a ship that goes inert resumes its intrinsic velocity, and matching intrinsics before contact is a standing rule (Chapter 4 of Galactic Patrol and throughout).

Sources

• McMonigal, Lewis and O'Byrne, Phys. Rev. D 85, 064024 (2012), arXiv:1202.5708 ✓