Circumspace is the 7+1D space that surrounds our 3+1D intraspace universe. All of existence is split into countless of these universes, with each their own laws and constants, and circumspace is what lies between them. Where most universes are higher-energy "false vacua", circumspace is the ground state, the bottom-energy "true vacuum" that occasionally births new universes by quantum fluctuation.
Uses of Circumspace
There are many different particles originating from circumspace, such as the pyron, a particle of heat; the scoton, a negative photon that transmits darkness; the cryon, a particle of cold that is the negative version of the pyron. Even the psyon, a particle of "intelligence", in a manner of speaking, can be found in circumspace. Some of these exotic particles are used in ammo-packs for Mechyrdian stormguns in the Army or private ownership.
Mechyrdian starships use circumspace for FTL travel; the universe within which Mechyrdia resides is curved, and so it's often a shorter distance between two stars by traversing circumspace, instead of just traversing intraspace. For such trips, it is necessary for the ship to create an intrafield, else the 3+1D intraspace inside of the ship will collapse and melt into the circumspace surrounding it. It's not pretty when they do that.
It is also possible to create pocket universes in circumspace, however these take a massive amount of inflaton particles to prevent from collapsing into a singularity when any amount of matter is put into them. Pocket universes are used by tech corporations to store computers for the cloud, they are used by banks to store safe deposit boxes, they are used by the Mechyrdian military to store equipment, some wealthy businesses even offer renting services for pocket universes.
It is possible to manipulate gravity using circumspace; gravity pumps pull gravitons out of circumspace and direct them in certain ways, pushing and pulling objects, making them explode or implode, or even creating wormholes.
Circumspace can be used for surveillance; universes can be viewed from circumspace the same way that a flat drawing can be viewed from 3D space.
There is a type of particle originating from circumspace known as the psyon. The nature of this particle is still unknown, as it seems to act in a way that indicates intelligence. Psyon fields resemble consciousnesses, and even become sapient when they reach a high enough energy. Naturally, sentient psyon fields have been embedded into material forms and marketed and sold as pets throughout Mechyrdia.
Psyon fields can be dangerous, however, when combined with a biological lifeform, as it will bind to that lifeform's brain and give it abilities that seem to resemble psychic powers. The Mechyrdian Army has made use of this, binding soldiers to psyon fields and transferring them to the Psy Corps.
The circumdrive is the method of faster-than-light travel used by Mechyrdian ships, as well as alien ships within the same universe.
Electrons and positrons are generated by normal processes, after which they are channeled through magnetically shielded tubes into a central reactor hull. The inside of the reactor is coated with crystal hyprite, and when the electrons and positrons annihilate, the hyprite generates circumspace plasma. This circumplasma is shunted into coils that generates a portal to circumspace, into which the ship enters.
The ship navigates through circumspace by using quantum computer systems that are able to do the calculations necessary to traverse the realm. It then exits by increasing the energy of its protective intrafield, which causes the ship to bubble back up into intraspace.
The circumdrive was first discovered by humans in 1444 OC (2069 AD). During its early years, the ships used cybernetic cables that plugged into the brains of human navigators in order to navigate, because quantum computers at the time weren't powerful enough to calculate circumspatial trajectory.