These articles are classic Science Fiction concepts that have been proposed in the real world but never implemented. They have since been integrated into the Halo universe.

Slipstream Space

Micro Dyson Sphere

Shaw-Fujikawa Translight Engine

Space elevator

Plasma

“Though often mistaken for cryogenics, which is merely the study of cold on materials, Cryonics...

Cryonics

“Orbital bombardment refers to the act of bombarding targets on a planetary surface from orbit...

Orbital bombardment

“For the Particle Beam Rifle, see here. A particle beam weapon is a type of directed energy...

Particle beam weapon