Quote:
|
Originally Posted by Tensor
Van Rijn and Fortis provided you with an explanation for why neutrinos cannot be focused at 1 AU (thanks guys, I didn't get back to this unitl tonight). Nothing says neutrinos (or other massive particles) can't be focused, but as neutrino mass have 30eV as an upper bound, their energies require them to be traveling almost at the speed of light (with 99.99% of c as a lower bound), which means the focal point for neutrinos will be approx 99.99% of the photons focal point. The photon's focal point is ~540 AU, a neutrino's will be at 539.9 AU, well away from the 1 AU you need for the focal point to be at 1 AU. If you disagree (but, then again, you claim you don't disagree with GR ) with this you've been provide the equations, [b]you[/] asked for. So either show us where the equations are wrong, or quit making this claim.
|
I did a little more research on this and apparently the focal point would be quite a bit closer for neutrinos. The issue is that the sun is essentially transparent to neutrinos so the paths of the neutrinos going through the sun as well as the ones going near it have to be considered.
Here is an abstract. This doesn't affect the issue at hand (the earth is still far too close to be at the focus), but it is interesting.
The key point here is the confusion of "focus" with "deflection." Yes, the sun will deflect both photons and neutrinos, but the earth is far too close to the sun to be at the gravitational focus for either. But, the earth doesn't need to be at the focus to measure light deflection. This would be
far more difficult to measure with neutrinos.