Warning: this is more of a nitpicking session
Here, I'll start with someone else:
Tony Stark: "Anti-electrons"
Nobody who knows anything significant about quantum mechanics calls them Anti-electrons. They're Positrons. The only time you see the term 'anti-electrons' is when dealing with virtual particles. Even then, they're almost always called Positrons, but saying 'electron/anti-electron pairs' helps reinforce the idea that it cancels with the electron and the net total is zero. Ruined the technobabble for me
Micro-singularities would be teensy ones that won't form by normal gravitational processes.
Just to reiterate..... singularities of any kind have no size. That's what makes it a 'singularity'. A point of infinite value and no size. So, are you claiming these singularities are spacial in nature? ie, they are points of extreme spacial distortion like the center of a black hole.
Take high energies to create and have short lives. Like the ones right after the big bang or in our case, artificially created with energy. I'll assume we create quantum singularities artificially, enhance their stability through some arcane process and then grow by feeding them additional matter until they achieve the sizes we want.
You seem to be mixing the term 'black hole' with 'singularity'. Black holes have a gravitational singularity at their center. they are not synonyms, however.
They will have to be charged in order to be spun.
Not necessarily. If you have a black hole and want to cause it to spin, but it currently is not spinning, the easiest way of doing that is if it has a charge. Then it will respond to magnetic fields and such. However, if in the process of creating it, it was already spinning... it does not 'need' a charge (however, it's likely to have one). you can't really change it's spin though, so whatever works.
"Fractional velocities of c" is just a pseudo-scientific blah-blah to mean, "Really fast so we can break the laws of physics in our story".
only velocities which are significant fractions of c are 'really fast'. 1/4000000000000000000000 is a fraction. however, this would not be very fast; and therefore is not a significant fraction of c.
Essentially the "rift" is a wormhole (since we already have those in-game and if we were trying to rationalize space fleet travel though wormholes we would have even bigger problems...not to mention FTL travel itself).
I merely was trying to point out there is a difference in terminology. A rift is more like the doorway between 2 rooms. A wormhole is like a hallway between to rooms. a rift is 2 dimensional, a wormhole is 3 or 4 dimensional.
As for energies, we're using antimatter and any other sort (vacuum energy, dark energy, etc.) to open the rift and we're going to assume the peculiar properties of the other dimension provide a strange sort of energy that let's us keep a wormhole going.
vacuum energy works best. You could even pull the energy from inside the wormhole, maybe suggest the purpose of the experiment was to draw energy from there in the first place but then the other side was discovered. maybe it was discovered because enough energy was drawn from the wormhole vacuum such that other endpoints became visible, but not reachable. So, a project was started to 'build' a wormhole to one of the other end points from scratch.
Travelling FTL and jumping space fleets through wormholes in game already breaks so many laws of physics we' aren't going to worry too much on this.
Note B was about how to flip the privacy switch on the wormhole, not the viability of wormholes. Please reread under this context.