[1] Not to be confused with Harvard’s Fred L. Whipple, leading authority on comets and coiner (in 1950) of the “Dirty Snowball” theory of cometary composition. [Return to text.]

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Question: A Synthetic Singularity?

by Theodore Sprott

Dr. Jack,

I’ve read Singularity by Bill DeSmedt and did some intense research on the subject. I had wondered: if you could somehow artificially increase the gravity in a specific area, then you should have a black hole? I played out a scenario but the end result is something -scientists- won't like. Okay, Here I go. The only way to achieve enough pressure to make gravity collapse upon itself is to set up theoretical “virtual gravity” condensers around this particular partition of the universe — a.k.a. the Sol[ar] Sys[tem] — and force it to megaply its gravity till it loses resistance and the whole S.S shrinks down into that point. This would require resources way beyond what you can find in our S.S let alone Earth, unless there was some other way...

— Correct me if I am wrong. I am a high school student who lives in Houston, TX —

Doctor Jack's Answer

Yes, sure, if spacetime could be bent artificially (synthetic gravity) you could, in theory, create a black hole singularity.

And it’d be permanent, too. It’d have to be. Because if the singularity went away when your spacetime bender was turned off, then us outside observers would be able to tell something about what’s going on inside the hole it created — namely, whether the machine that created it was switched on (black hole) or off (no black hole). But you can’t get information out of a black hole — that’d be the same as information traveling faster than the speed of light, and that’s forbidden by general relativity. So, once it formed, your black hole would be here to stay.

The problem is that — short of simply piling up an enormous amount of mass — nobody’s got the faintest idea how to put that kind of a bend in the spacetime continuum. Worrying about the consequences before you’ve built the machine is like leaving out step one of the old Texas recipe for rabbit stew: “first go on out and catch yourself a rabbit!”

This is a mighty big rabbit.

Me, I don’t think it’s possible at all. But to see why not, we’ve first got to work our way through a “thought experiment” or two

Before we start, though, recall that energy is never created or destroyed. The most we can do is convert it from one form to another. (One of those forms of energy happens to be called “matter,” but that makes no never mind here.)

Got that? Now, turn on your “gravity generator.” It immediately becomes a new center of attraction, meaning that everything in the universe (well, everything as far away as light has traveled since you turned it on) is now at a higher gravitational potential.

In other words, all the objects within reach of your spacetime bender have acquired energy — the same sort of potential energy as a rock’s got when it’s sitting balanced at the top of a high hill. What’s more, all those objects will now have a tendency to start drifting towards the new attractor. They’ll begin trading their potential energy of position for kinetic energy, energy of motion, like that same rock when it comes loose and starts rolling down the hillside.

Still, no matter how you slice it, all the matter surrounding your generator somehow possesses some energy it didn’t have before.

But we just got done saying that energy can’t be created or destroyed. So where did all that extra energy come from? The batteries powering your gizmo? They’d have to be very good batteries.

You get a gravitational field equal to the Earth’s by assembling a mass equal to the Earth’s. That’s about six sextillion tons worth. It can be rocks, socks, old alarm clocks — or a dry cell loaded with six sextillion tons of energy. Energy is mass. It contributes to gravity. A charged capacitor or inductor has more mass (and more gravity) than one that’s not charged — even though not a single subatomic particle has been added.

In other words, if we have enough energy to power your gravity generator, we don’t need the gravity condenser. But this is an expensive way to catch that rabbit!

The real question is: can we create a gravitational field equal to the Earth’s using an amount of mass (or energy) less than the Earth’s? (Ideally, we’d want to use a lot less, but in this thought experiment the principle’s all that counts. Saving even a kilogram’s worth is as hard as saving 5.99999 sextillion tons.)

More particularly, could we build a machine — a spacetime generator, a Sprott gravity condenser — that would do this trick?

Probably not.

A gravitational field is just another kind of energy storage, like an electric or magnetic field. A transformer builds up a magnetic field by running a current through coil A and then collapses the field to induce a current in coil B. All the energy is recovered (except for the little bit lost as waste heat). If the field could be collapsed so as to yield more energy than it took to make it in the first place, then we’d have perpetual motion. (Gas prices being what they are, let me know if you figure out a way to catch this rabbit!)

We can balance off two different types of field.

Run a current through a copper coil and you get a magnetic field. An iron bar will be held firmly inside. I can pull it out — at the cost of doing work on it — and the energy I expend adds to the flux in the coil. When I let go, the bar is yanked back. Its kinetic energy comes at the expense of the field. The current decreases again.

If I have two coils, some distance apart but on a common axis, you can imagine one end of the iron bar entering coil B while the other end leaves coil A. The forces oppose and cancel. The energy lost in B is the same as the energy gained by A. In fact, I could wire the two in series and the total energy in the circuit would remain unchanged, just as if the bar was moving within the uniform field of a long solenoid.

All right, I have here a coil made from Sprottium wire. Sprottium is a rare element with the property of generating a gravitic (not magnetic) field when it carries a current, okay? Now I can do essentially the same experiment with, say, a lead bar. One generated gravity field opposes the other. There’s no net force on the bar. No net gain or loss of energy.

Finally, I’ll wire one copper coil in series with a Sprottium coil. One end of the bar is iron, the other lead. Moving it cycles energy between electric, magnetic, kinetic, and gravitic, but the total never changes.

Imagine some redesign of a coil (either coil) that allowed us to get the same field but that required only half the energy. The equations no longer balance. Moving the bar left/right means energy will appear/disappear.

So all methods of generating any particular field require the same energy input. Different winding configurations will change the shape of the field, but not the stored energy If we know how much energy it takes to create a field by one method, we know how much it takes by any method. And we know how much energy it takes to make gravity: six sextillion tons of mass- energy to “fake” the Earth’s field. Any “cheaper” method would violate the principle of conservation of energy.

A good guiding principle is that we never create forces. We merely rearrange matter so that existing forces do what we want. For example, a lump of untreated soft iron has plenty of magnetism; it’s just in the form of tiny domains which point in all different directions and, from a macroscopic viewpoint, cancel out. By pounding on the iron we can realign the micro-fields so they add up. Have we created magnetism? No. We’ve just molded it into a more obvious — and more useful — form.

If space was permeated by “virtual” energy fields — which is what I think you’re trying to “condense” — then there might be a way out. All the energy we’d need would already be there, and all we’d have to do is realign it (with a patented Sprott gravity condenser) to make it, too, useful.

It could be. The energy from quantum fluctuations even in a vacuum — the so-called “zero-point energy” (ZPE) — is enormous. Cup your hands together. Now imagine a vacuum bubble small enough to fit in the space between them. Theoretically, there’s enough energy in that bubble to boil all of Earth's oceans into steam.

We don’t notice the ZPE because it’s a constant, unchanging “background.” Usually we only notice energy when it’s doing actual work, and work only gets done when there's a change of energy. A boulder atop a mountain won’t smash anything unless there’s a valley for it to drop into.

On the other hand, vacuum-energy (or any other fields you might imagine) can’t be simply swept under the rug in general relativity. There, energy always produces a gravity field — a curvature of space and time. In fact, ZPE implies so much curvature that the entire universe ought to promptly implode into a black hole. We are still here so, clearly, we’re missing something. This is a Major Unsolved Problem.

I hope you weathered the storm okay. And that you’ll keep on asking questions.

Yours truly,
Jack Adler

copyright (c) 2005 by amber productions, inc.

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copyright (c) 2005 by amber productions, inc.