Editing Exotic matter (section)

== Negative mass ==
{{Main|Negative mass}}

Negative mass would possess some strange properties, such as accelerating in the direction opposite of applied [[force]]. Despite being inconsistent with the expected behavior of "normal" matter, negative mass is mathematically consistent and introduces no violation of [[conservation of momentum]] or [[conservation of energy|energy]]. It is used in certain speculative theories, such as on the construction of artificial [[wormhole]]s and the [[Alcubierre drive]]. The closest known real representative of such exotic matter is the region of pseudo-[[Pressure#Negative pressures|negative-pressure]] density produced by the [[Casimir effect]].