Sunlight is electromagnetic waves with a range of frequencies higher than the cosmic background radiation but still basically waves of photons. Photovoltaics (solar cells) are devices that generate electricity from the interaction of photons with the engineered crystals of the device.
Solar sails are devices that currently propel some spacecraft from the force emitted when photons rebound from the reflective material of the sail. Making such sails that run on cosmic background radiation is a bit trickier than making photovoltaics that do because the sails would have to be in a state that reflects the electromagnetic waves only when you'd want them to accelerate the vessel; even if you covered them they would accelerate the vessel if in a state that reflects the photons of the cosmic background radiation because the cosmic background radiation can travel through most material.
The diffusion of thermal excitation across a creased manifold is not random and follows the laws of gravity as its organizing principle inside the wormhole. This statistical principle leads me to conclude that the orthogonal continuum does not stand alone but is bound by extrocontinuum which capture the centrifugal force of space-time.
Some super-colliders make antimatter and heavy elements. Such atomic colliders use magnetic techniques to make particles collide at a certain speed; as new devices for accelerating atoms are developed such colliders will miniaturize (like computers) as such particles are accelerated to the same speeds over shorter distances. Antimatter is stable in a vacuum.
I imagine there will be solar-powered anti-matter generators in our solar system. Anti-matter has a much larger energy potential than an equal mass of fissionable material, but I do not think any fuel (even anti-matter) could last a vessel through inter-stellar travel. Perhaps for more local missions anti-matter and matter could be simultaneously released into each other at the site of the thrusters replacing rocket-fuel explosions as the propelling force of the thrusters.
An atom drifting through space continues to exert its subatomic forces while retaining their inertia; this suggests the exacontinuum is a tapering force which is related to the Boltzmann constant.
I would like to see a propulsion system based on a surface that pushes on the hull when electrically induced. Such a surface would be between the hull and another surface which mobilizes an electron field in the inner surface by pushing the inner surface's electron orbitals in the direction of the hull thereby inducing the inner surface to push on the hull, ncessarily a tunneling-proofed section of it! The outer surface would thus adopt the massive momentum as the inner surface pushes it.