## Inertial Mass Separate From Gravitational Mass? 405 405

CPerdue writes with this excerpt from the MIT arXiv blog:

*"The equivalence principle is one of the more fascinating ideas in modern science. It asserts that gravitational mass and inertial mass are identical. Einstein put it like this: the gravitational force we experience on Earth is identical to the force we would experience were we sitting in a spaceship accelerating at 1g. Newton might have said that the m in F=ma is the same as the ms in F=Gm1m2/r^2. ... All that changes today with the extraordinary work of Endre Kajari at the University of Ulm in Germany and a few buddies. They show how it is possible to create situations in the quantum world in which the effects of inertial and gravitational mass must be different. In fact, they show that these differences can be arbitrarily large."*
## Next stop: Arisia (Score:5, Funny)

Because once we have inertial drives, it's only a little while before we can colonize other planets.

The technology lens itself very well to that.

## Inertial Dampeners??? (Score:5, Funny)

## Re:Next stop: Arisia (Score:5, Funny)

The technology lens itself very well to that.

I sea what you mean.

## I would submit.... (Score:5, Funny)

## Re:Next stop: Arisia (Score:2, Funny)

Your comment will go over the heads of many, but ...

Dude. Nice one.

## Re:Inertial Dampeners??? (Score:5, Funny)

I will take the option of seatbelts while sitting at the bridge of your spaceship, thank you very much.

## Re:I would submit.... (Score:5, Funny)

## Re:Quantum (Score:2, Funny)

## Re:Inertial Dampeners??? (Score:5, Funny)

## Re:I would submit.... (Score:5, Funny)

You mean this one [xkcd.com] from 2004?

## Johann Gambolputty (Score:2, Funny)

## Re:Inertial Dampeners??? (Score:1, Funny)

Why, so when it comes to a screeching halt, you are cut up into multiple pieces so you can get a nice scatter-shot pattern of paste on the window?

## Re:Inertial Dampeners??? (Score:5, Funny)

That's "dampers", unless you're talking about devices that make the bridge slightly moist when the ship is subject to acceleration.

We call those red-shirts around here.

## Re:Inertial Dampeners??? (Score:4, Funny)

In space, no one can hear you screech.

## building anti-grav spaceship in my garage now (Score:4, Funny)

There a few bugs to be worked out however. First, the grav-shield must be aligned within ten arc-seconds perpendicular to main gravitational body (Earth) or gravity leaks through. Second, stray cosmic rays have the disturbing habit of energizing the condensate about the phase-change temp and destroying the null-grav effect. I hope to have fixes by next week.

## Re:Sure, here you go (Score:4, Funny)

The standard crackpot "a single equation" makes me want to cry, but the "see t-shirt below" part more than makes up for it.

## This Can't Be (Score:3, Funny)

If he's right, they'll call it that "Kajari Drive". That just doesn't ring for me. We need someone else to refine this and make it go. An Archer maybe, or a Cochrane. Now those are names a real space drive can wear. Hell even inter-compartment conduits get names like Jefferies Tubes. Kajari? No way. He can have an episode of his own when they serialize history (as we know they have, so we can see it but consider it fiction thus avoiding paradox), but not the name of the drive.

## Re:Dark matter? (Score:5, Funny)

More importantly, it means that one pound of dark matter COULD weigh over ten thousand pounds!

## Re:Inertial Dampeners??? (Score:5, Funny)

That's a bloody good joke, sir.

## Re:Inertial Dampeners??? (Score:5, Funny)

Color me baffled. Are you disagreeing with him or not? ;)

## Re:Next stop: Arisia (Score:5, Funny)

Your comment will go over the heads of many, but ...

Dude. Nice one.

Oh, come on now. You must have meant "Nice won."

## Re:Sure, here you go (Score:3, Funny)

Oh, I can easily write all equations of Physics into one equation.

To see how it works, let's assume I want to "unify" the Schrödinger equation and Einsteins field equation (don't worry about the fact that the Schrödinger equation is non-relativistic ...).

Schrödinger: i hbar d/dt psi = H psi [d here should be the partial derivative sign]

Einstein: G = 8 pi gamma/c^4 T [gamma here is the gravitational constant, because G is already used for the Einstein curvature tensor]

The first step is to bring all terms to the left side:

Schrödinger: H psi - i hbar d/dt psi = 0

Einstein: G - 8 pi gamma/c^4 T = 0

Note, however that the "0" in the first equation is a null vector in the quantum mechanical Hilbert space, while in the second equation, it's a tensor in spacetime. Those are not compatible. However, in both cases, we can choose a norm (in the first case, the standard Hilbert space norm can be used; in the second case, any matrix norm will do). Note that the norm need not to make physical sense; the only thing we need is that it maps to the non-negative real numbers, and only the zero object of the respective quantity is mapped to the real number zero. Denoting both norms with ||...||, we get:

Schrödinger: ||H psi - i hbar d/dt psi|| = 0

Einstein: ||G - 8 pi gamma/c^4 T|| = 0

Now we have two non-negative real numbers which shall be zero. Their sum is zero exactly if each one of them is zero. Therefore we can combine the equations into one:

||H psi - i hbar d/dt psi|| + ||G - 8 pi gamma/c^4 T|| = 0

From this equation, one can easily derive both Einstein's field equation and Schrödinger's equation. Therefore I just unified quantum mechanics and general relativity. :-)

## Re:Inertial Dampeners??? (Score:4, Funny)

Hm, maybe you're onto something - that

could, maybe, account for exploding control panels... (not to later problems with repairing them, though)## Re:I would submit.... (Score:2, Funny)

Dude, seriously, that's fucked up. This xkcd man must be a genius or something. Holy fucking shit! LOL. LOL. LOL.

## Re:The really important question ... (Score:1, Funny)

Yes.

## Cartman (Score:3, Funny)

I don't have a lot of gravitational mass ... it's my bones that have a lot of inertia.