paragravity

March Question Roundup

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14

Just realized I never did answer these:

First, are you familiar with Stars in Shadow, yet? If so, what do you think the Empire of the Star would make of the Phidi and the Phidi Combine?

Caveat: I haven’t played it myself; for various and sundry reasons, I try to keep my gaming to the Xbox, these days, so I’m going purely off the description, et. al., on the web site.

That said, based on it, I imagine you’re quite correct in saying that they’d probably get on like a house on fire, indeed. (After all, government by purchased office is hardly an unfamiliar concept to the Empire – just look at Eävalle.) A lot of cultural compatibility, of course, depends on how much governing the federation of merchant princes mentioned actually feels inclined to do, but plutocracies are hardly the government type most likely to want to be all up in everyone’s business, so unless there’s a non-obvious/unlikely cronyist nightmare hiding behind the scenes, it doesn’t look like there’s a problem there.

Second, on paragravity and using it to attain orbit, a real simple answer: you can’t. Even if you solve the obvious problems, like providing the energy, and (since it only operates between two paired units) completing the circuit between two units one of which is presumably in geosynchronous orbit over the other, there’s a more fundamental issue.

Namely: achieving orbital altitude is only half the problem. To stay up there (bearing in mind that orbit is essentially falling around and around the planet), you also need orbital velocity sufficient to ensure that you keep missing the ground. Hiking yourself up there paragravitationally gets you the former, but not the latter – and, note, everything that’s already in orbit necessarily is moving at orbital velocity.

So the first thing that’s likely to happen after you reach orbital altitude is a fatal collision with something already up there moving at umpty-thousand mph relative to you. This will knock whatever of you survives out from between the paired paragravity units, at which point in obedience to that harsh mistress, real gravity, you will plummet immediately and directly back to the planet, with another fatal collision – and a lawsuit – awaiting you at zero altitude. (If you aren’t hit by something up there, the same plummet awaits you just as soon as the paragravity units are turned off, or you voluntarily move out from between them.)

Basically: you will not stay in space today.

 

Cloaking

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From: Capt. Isvieve Kalyn, Procurement, Resplendent Exponential Vector
To: Adm. Gilad Tsurilen, Bureau of Innovation
Subject: FAT NINJA progress report
Security: SECRET (GREEN) FAT NINJA

Development on project FAT NINJA itself is essentially complete. Our research contractor has successfully demonstrated a prototype design capable of using intense paragravitational fields to distort the fabric of space-time in such a manner as to place the prototype within an enclosed polypoid volume of distortion, connected to the original location of the prototype by a narrow “neck”. They have further demonstrated limited communication capacity through this “neck”, suggesting that it would be theoretically possible to monitor events outside the distortion using a small drone vehicle, rendering FAT NINJA a non-double-blind device.

Unfortunately, no progress has been made on the fundamental problem of sustaining the distortion in the light of fundamental thermodynamics: necessarily, an enclosed polypoid volume suitable for preventing detection retains all radiation, including waste heat, emitted by the objects within it. Were the distortion to be handwaved into existence, this would be merely an irritating limitation; however, given the extremely high energies required to create the distortion, even with the most efficient power generation and paragravity equipment available, FAT NINJA is able at best to sustain a cloaked state for a matter of milliseconds before undergoing a catastrophic thermal excursion leading to complete vaporization of the prototype and immediate reversion of the cloaked volume.

While the experiment was worth doing, I must conclude that this is a physical limitation of all FAT NINJA type devices, and in the absence of some new fundamental breakthrough with regard to the thermodynamics of the case, FAT NINJA is a dead-end – at least as a cloaking device.

It does, however, make a rather splendid, if outré, bomb.

In service and glory,

Isvieve Kalyn (Capt.)

 

Handwavium: Paragravity

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Okay, let’s talk about paragravity.

First up, a note on nomenclature. Paragravity is one of the two things that an Imperial habtech might be referring to when they talk about artificial gravity, the other being spin gravity. Unlike spin gravity, which is “powered” by good old centrifugal force, paragravity is produced by ontotechnological space magic that does wonderfully complex things involving information physics and grand unified theories and other such things to poke the universe in exactly the right way – basically, one branch of the mass-inertia-and-momentum manipulating vector control.

Which is to say that it is produced by gravity rotors, suitcase-sized boxes with a power connector, a ‘weave connector, and a thermal management connector on the outside, filled with solid-state hardware that is a proprietary product of Mariseth Gravitics, ICC. And into whose internal workings we shall thus respectfully avoid going.

What we’re talking about here is how they work on the outside.

The field of paragravity (the gravity envelope) can only be created between two gravity rotors of opposed polarity. That gets you a straight field (with perhaps some convex distortion at the edges) between the two, which imposes a force functionally identical to mass-generated gravity (i.e., affecting all atoms, etc., equally) on everything with mass inside it.  This creates a consistent down direction towards what, for the sake of designation, we shall call the “positive” rotors.

(You have to have a closed envelope, and can’t operate an unpaired gravity rotor even if you wanted to: since the universe is functionally infinite in whatever direction you’re pointing it, energy requirements for the half-field head asymptotically for infinity, at which point the circuit breakers save you from a messy ‘splosion.)

Both momentum and energy are conserved, as they would have to be.

The former is the reason that you gravity rotors should be bolted firmly to the structure of the hab; whatever force they exert is, per Callaneth’s Lemma (or Newton’s Third Law, whatever name you prefer), reciprocally exerted too, half to each rotor in the pair.

While difficult to arrange even deliberately, this does imply that if you can get enough mass in one spot and move it just right, you can get the gravity rotors to tear themselves free and leap in the appropriate reciprocal direction.

With regard to the latter: it takes energy to establish the gravity envelope, but once it’s up and running, maintaining it takes only minimal energy physically speaking. (I.e., it still consumes quite a bit of energy in the rotor while it’s up and going, because rooting the universe ain’t cheap; that energy just doesn’t go into the envelope.  It’s this waste that makes paragravity a real expensive thing to run.)

That, however, is only true so long as nothing is moving within it. Falling objects, moving in the down direction of the envelope, take energy from the envelope as they gain kinetic energy.  (Likewise, when you lift an object within the envelope against its downforce, that pushes energy into the envelope, which is a surge effect that the hardware has to cope with. Alas, it’s not something that can be harvested in the majority of applications.)  You could call this paragravitational potential energy if you like, since it sits in essentially the same place in the relevant equations.

While it takes the rotors a little while to initialize from a cold start (although some of this time is self-diagnostics and the like), once up and running, though, you can change the parameters of the gravity envelope very quickly; and you can generate pretty much any amount of gravity you want up to their capacity so long as you’re willing to spend the energy (which varies proportionately) needed to do it.

This is what lets you use the exact same technology for inertial damping; you just have appropriately oriented gravity rotors cancel out your engine thrust inside the starship – while bearing in mind that this will have certain effects on your structural load. (Likewise, you can use them when grounded – but since they don’t block planetary gravity, if you want 1G in the cabin when landed on a 3G world, you will actually be running the paragravity system at -2G.)

The drawback, however, is that the same lack of “inertia” in operation that lets you change your gravity quickly means that they fail equally quickly – and shut down essentially instantly if the power fails, just like an electromagnet’s field collapses – so failing to keep up maintenance schedules may mean being abruptly smashed to the deck with a force of twelve gravities! Caveat engineer.