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Intel don't use GAAP then?

If you really like "hard" science fiction -- that is sci-fi that is deeply technical, believable, and thought-provoking, you should check out Forward. He is mostly a scientist, and thus isn't as prolific as other authors and is often forgotten. But how many sci-fi authors do you know who have received funding from NASA for ideas they are working on?

His books will keep you up at night wondering just how possible what you just read might be. And astonishingly, he is also a very good storyteller! Think Asimov meets Hawking here...

First, antimatter "explosions" are actually fizzles, because P-barP reactions at rest tend generate neutral and charged pions and kaons, and neutrinos.

Neutrinos don't interact significantly with matter, so that energy is effectively lost. The neutral pions and kaons interact with the weak force only, and hence carry energy away for quite a distance (kilometers for pions) before they decay into something that does interact with matter. 50% of the time for every charge particle you get m neutral particles, where m>2 (see references

That means that most of your energy is carried kilometers or more away (for the relativistic ones) before decaying into energetic particles that DO cause things to go boom. The energy of the antimatter tends to be dispersed through a rather large volume.

Antimatter is, however, extremely valuable for rockets, due to a unique advantage. The general Hohman-transfer equation, which governs interplanetary flight, has a term exp{V/V0}, where V is the exhaust velocity and V0 is the "mission velocity", defined to be the delta v necessary to achieve a particular orbit.

For example, V0=11.2km/sec for orbit, and ~29km/sec for Saturn. Note that getting into Earth orbit gets you almost halfway to anywhere.

The propellant/load ratio, which is how much propellant per unit of mass you need to get somewhere, therefore depends (exponentially) upon the ratio of V/V0. Now, V is limited in chemical rockets to be at best 7.4 km/s for O1/LH2, so you have a built-in, exponentially growing ratio of rocket fuel you must carry per kilogram of payload. This makes manned flights to Saturn impractical with chemical rockets.

However, an antimatter rocket has no built-in limit on exhaust velocity. Solving the equations, that means that you can get to anywhere on an antimatter rocket with a fuel/payload ratio of 5:1. That doesn't sound great, but it's much better than 100:1 for orbit or 300:1 for interplanetary flights.

And, in fact, with antimatter rockets you can start *thinking* about not using Hohman transfers (which minimize the necessary energy) to get someplace, and can consider minimizing your time instead. You'll need the same fuel ratio, just more antimatter to increase your exhaust velocity V. Forward has a design for a basic antimatter rocket he did research on for the USAF.

Finally, there are ways to store antimatter for weeks at a time, using Pfenning traps and other magnetic facilities.

Antimatter, however, makes a lousy energy source, as it must be fabricated, you get less out of it than you put into it (we're currently .0000001% efficient, according to R.L. Forward's estimates) -- it's essentially an inefficient battery. For the same reason, antimatter is not a particularly good weapon. If you had an "antiproton" particle beam, 99.9% of the energy is coming from kinetic energy, and the inefficiency in handling/storing antiprotons isn't worth the measly 0.1% energy you get out.

But it's a wonderful rocket fuel.

--Adam

Robert L. Forward also wrote about elevators (up and down, slinkying across the lunar surface) in Timemaster.

You can always trust Rober Forward to come up with a good idea.

See his Terminator Tether page. It's a great way to bring down an orbiting mass without actually having to carry the mass of fuel that would be required for a deorbiting burn.

Please refer to Dr. Robert Forward's Guidelines to Antigravity. While his paper dealt with rapidly moving, super-dense fluid accelerating around a torus, perhaps (if Chiao's theory is verified experimentally), the equations can be worked out for superconductor-generated gravity waves.

Modern physics theory says that there is a tremendous amount of energy in otherwise empty space. But no existing device can tap this.

I first read about vacuum energy in a book called Indistinguishable From Magic by Robert L. Forward.

Of course, if the brightest physicists in the world haven't been able to come up with a practical method for tapping vacuum energy, I don't for an instant believe that some guy who isn't even a physicist managed to figure out how to do it in his garage. And I certainly don't believe he'd be keeping its inner workings (or his identity or his location, for that matter) a secret if it was real. If this was real, and he published, he would win an instant Nobel prize. But he won't publish, because he's a complete fraud, and he knows it.

Good questions. The only comment I have is that unfortunately gravity waves do not cancel each other out when a "wave" meets a "trough". I put this exact question to none other than Dr. Robert Forward (many years ago at a seminar on advanced space propulsion methods), and his answer was (IIRC) "Gravity waves don't do that because they have a much more complicated structure than light or sound waves."

I have attended several panels by Dr. Robert L. Forward on the subject of space teathers and elevators using current materials. Interested parties should check out his company, Tethers unlimited Inc as well as his personal site. I don't know where he will next be lecturing, I last caught him at VikingCon 17 (Western Washington Universitie's SciFi convention).

http://www.whidbey.com/forward/

This was actually proposed by Dr. Robert Forward as a means of propulsion. He wrote sci-fi novels (see Saturn Rukh) but had a hard scientific basis for it. Look it up at his site and look up HoyTethers.