oz93666 wrote:CharlesChandler wrote:So what is involved in the collision -- a single particle, or the whole bunch, or something in-between?
But we're digressing, not only has Einstein's mass energy equivalence been proved, but also the idea that time slows down when moving, particles with a known half-life live longer when moving at speed in these accelerators.
Ummm... you didn't answer my question.
To accelerate the discussion, the next question is: assuming that the particles are traveling in clumps, and that the velocity of the clump is accurately measured (because that sounded reasonable), how is the total energy in the collision measured?
The reason for the question is that I can easily think of a way that energy could get stored in something other than momentum,
and other than mass, giving the illusion that GR had been proved, when really, it hadn't. The energy could get converted to electrostatic potential by a z-pinch.
To explain the question, I'll start with a metaphor. Let's consider a supersonic aircraft, that has adjustable wings, which are perpendicular to the aircraft in subsonic flight, but which get tucked parallel to the aircraft for supersonic flight (such as the US F-14). Now let's suppose that this is accomplished just by making the wings spring-loaded, such that with increased drag on the wings, they tuck themselves in when approaching the speed of sound. This would mean than in tucked position, some of the thrust has been converted to elastic potential. If the drag is reduced, that potential can get released, getting the wings to spread out again. So if the plane is instantaneously decelerated (because it hit something), there is of course all of the momentum of its forward motion, but there is also the release of that elastic potential. This would make it look like the plane was releasing more potential than just its resting mass times its forward velocity.
Similarly, charged particles at relativistic velocities undergo a z-pinch, in which despite their electrostatic repulsion, the magnetic pressure forces them together. If they could ever achieve the speed of light, the magnetic force would become equal to the electric force, and the particles would fuse (even without any spins that create relative motions in a charge stream, encouraging fusion). Of course, actually accelerating particles to the speed of light is tough, because the accelerator is EM fields, which travel at the speed of light. So while energy is still building up in momentum, or being lost in particle spins, the forward velocity is less than the speed of light. But there is another force that needs to be overcome to achieve the speed of light, other than the particle clump's resting inertial force, and any Lorentz forces due to conflicting magnetic fields, and that's the Coulomb force between the particles. So as you pump energy into those particles, and they get going faster and faster, as you approach the speed of light, you start seeing energy absorption beyond what shows up in forward motion, or in particle spins. Where did the energy go? And then, on collision, all of the input energy is released, beyond just what you'd get from the forward motion. So where did that energy come from? A portion of the energy release on collision will be electrostatic potential re-converted to kinetic energy, because as soon as the particles are decelerated on collision, the z-pinch goes away, and the electrostatic repulsion takes over, accelerating the particles away from each other. In other words, there will be a Coulomb explosion. This might look a whole lot like the conversion of forward motion to radial motion in an explosion. But the energy will exceed that of the forward motion. So you do the F=m*a thing, where you know the force of the explosion, and you know the incoming velocity, and you adjust the mass accordingly, and you think that you have proved GR. Oops, you didn't take the Coulomb explosion into account.
So, in order for me to be convinced that energy is being converted to mass, I need to see where they're explicitly acknowledging electrostatic potential as an energy store. Otherwise, I'll conclude that they (once again) forgot to take a known force into account, which created a discrepancy, which they then called proof of GR, but which actually is just proof of their sloppy method.