The Warp is a psychic dimension parallel to real space. It is known by many names: Warpspace, the Immaterium, the Empyrean, the Ether (sometimes spelled Aether), the Sea of Souls,[10][26] the Othersea,[12] otherspace,[17] Sha’iel[18] and also as the Realm of Chaos[4].
Warpspace is a mirror dimension of pure energy. Existing as a mirror to our own reality, the Materium, it is the domain of the Gods of Chaos.[5] These Gods dwell in their own realms, perpetually battling for one another in a struggle known as the Great Game. The size of these realms expands and contracts as the power of the Warp ebbs and flows.[8]
The Warp's existence is fueled by the emotions and souls of all sentient beings in the Materium.[5] Warpspace is without form and the laws of time and space do not apply there, for both size and time are simultaneously infinite and irrelevant within The Warp.[3a] Its energies are in constant turmoil, subject to endless disturbances.[3a]
The common analogy used to describe Warpspace compares the Warp to a vast sea of energy, which is subject to constant movement, currents, undertows, etc. Immaterial space and real space bear a relationship as the dimensions parallel with each other. The fact that they share this relationship allows a Warp-capable craft to enter the Warp, carried for a time along the Warp flows until reemerging into real space a distance away from its starting point. The common metaphor used for Warp-jumping compares the Warp to a fast flowing stream. Its motionless banks represent real space. A leaf dropped into the water upstream will be carried along by the currents. This is a useful metaphor in understanding Warpspace, although the Warp is far more complex in its movements than a linear stream. The Warp moves in endlessly unpredictable and convoluted patterns.[3a]
The Warp is the final destination of the deceased souls of most races of the Galaxy. These souls will swirl endlessly within the Chaotic eddies of the Warp, and many are consumed by preying Daemons.[4a] Perhaps fortunately for the vast majority, particularly the minimally psychic, they swiftly lose any sentience and will perceive only the nothingness of oblivion.[16] The Craftworld Eldar use Spirit Stones to protect their departed souls from becoming the playthings of Slaanesh.[7] While the Harlequin Eldar rely on the protection of the Laughing God.[8] The Imperials believe that the Emperor will protect a virtuous soul once it has entered the Warp[9] while the Orks are spirited to the Great Green under the protection of Gork and Mork.[14]
The Warp is born from the thoughts, dreams, and emotions of every psychically attuned sentient race in the Galaxy. Every emotion and action in the Materium feeds the Warp and it is reflected back, creating its own reality. Should the races of the Galaxy somehow be cut off from the Warp, its malevolent entities would ultimately weaken and starve.[6]