Even though we do not know if it exists or not, how would negative inertia work in accordance to f=ma when an object has a negative mass? Would the negative inertia allow acceleration?
Negative mass would cause a violation of the law of conservation of energy. It would respond to the gravitation of other, massive, bodies like any other mass, negative or not, but the negative mass itself would cause a repulsive gravitational field. This could result in a two body system, that constantly accelerates through space without any source of energy. This ain't exactly what you asked for, but still.
No, only the gravitation that it "generates" would cause an opposite effect. The bodys acceleration in a gravitational field doesn't depend on its mass, but only on the mass of the body that causes the field. So to say, if the positive massed body makes a concavity in the spacetime, then the negative massed body causes a "hill". Anyway, negative mass would mean negative energy density and I dont think thats allowed by the laws of physics. Mass is, by definition, something that can only be positive.
Not having done any calculations, I would assume that introducing negative mass into the formulas, it would mean that to make the body come towards you, one should push the body and to make it go away one should pull it. Which is clearly nonsense.
That wouldn't be a violation of any law. Because the center of mass won't move even though both masses move in essentially the same direction. One mass is negative, remember?
I'll have to look into it a bit more.. edit: If the negative massed body has a bigger negative mass than the positive massed bodys mass, then both bodies will be affected by an equal force directed away from eachother. But since one body has negative mass, then its acceleration will still be towards the other body, not away from it. Remember, a=F/m and if m is negative then so is the acceleration. This will result in the negative mass accelerating towards the other body and the other body accelerate away from it. Since the negative mass is greater then it will finally lag behind, but still the conservation of momemntum is violated. If both have equal but opposite masses, then the system is stable. And if the positive mass is greater then the negative massed body will catch up with the other body and crash into it. The centers of mass will still probably be away from eachother, but the distance is relatively small, so the bodys will still accelerate in a direction pointing from the negative massed body towards the positive massed body. Constant acceleration with no source of energy. Unless there is some law of nature that causes the mass of the bodies converted into energy. Assuming that the negative mass can exist in our universe, which I doubt.
There never was any violation of conservation of energy. It might continue accelerating forever, but there is no work being done anywhere.
Conservation of momentum follows directly from F=ma. So it won't be violated as long as the mass follows the force law. You're forgetting that since one of the masses is negative, the center of mass is not where you would intutively place it.
If one of the bodies has a bigger mass, then the total mass of the system won't be zero. Actually, if the masses are equal and opposite then there will be no acceleration. But as I said if the positive mass is bigger, then there will be a constant acceleartion pointed from negative mass body towards the positive mass body. Both of them will have a constant acceleration and because the total mass of the system is positive, then the conservation of energy does not hold.
Sure there will! F = G.m1.m2/r<sup>2</sup> a1 = G.m2/r<sup>2</sup> a2 = G.m1/r<sup>2</sup> If the masses have different magnitudes, then the accelerations won't be equal or constant. What about complex mass? How much would that screw things up?
What about the negative energy density fo3 mentioned? Does anyone know if that is a valid point, is a negative energy density possible or is it nonsensical in all cases? I was dabbling years ago with a gravity theory of my own and came to the conclusion that a negative energy was nonsensical. Any thoughts anyone?
I have an vague idea, possibly (probably?) wildly incorrect, that the zero point for energy density is arbitrary. Isn't inflation supposed to have been triggered by a change in the zero-point of energy density, or something?
Gravity causes equal and opposite force to act on the bodies. If a 1kg ball is on earths surface, it is affected by a force of 10N directed towards earths core and at the same time a 10N force is affecting earth and is pointing towards the ball. And then we could also talk about the extremely small force that the balls mass causes on both bodies. So, if two bodies have masses of -m and +m, then the net force on both of them will be 0.
Hawking radiation should actually include some virtual particles with a negative energy density entering the black hole, but I'm not sure how that works. Just a notion about negative energy density.
But the net mass is also zero, so that doesn't tell us anything about acceleration. Each object does have a net force, so each object will accelerate.
No conservation of momenum cannot be violated. You're forgetting that one of the masses is negative. So the center of mass will remain stationary eveen though both bodies may move in the same direction.
Actually I think it is simply due to a lower, but non zero energy density of the quantum vacuum inside the plates than outside.
If the negative and positive masses are equal and oppositem the net force on either of the bodies will be 0, therefore no acceleration. If the masses are not equal and the net weight of th two body system isn't zero, then the system will always start accelerating towards the body with smaller absolute mass, and the lighter body will escape the heavier one. Could anyone tell me what happens to the center of mass if both bodies start accelerating? The formulas should give a result that follows the conservation of momentum, but I'm still having my doubts.
