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Beaming Neutrinos Through Earth?
TheMatt writes: "An article at PhysicsWeb talks about a proposed project by scientists at FermiLab. The project would involve sending a beam of neutrinos 10,000 km through the earth to a detector at SuperKamiokande. The hope is that passing through so much matter would alter the beam enough to better study CP (charge-parity) violation."
If we send a message through the earth, rather then arround, we cut our latency by 1/3 - and thats ignoring and routers enroute. This could revolutionize quake!
In the future, just after contacting with alien civilizations, we humans will be able to chat with the aliens about all the funny physics experiments we came up with, and ask them if they also carried them out. Imagine the conversations:
Human: By the way, did you try to beam neutrinos across your planet and gain some insights into the charge-parity violation? We based all our theories on the results of that revolutionary experiment.
Alien (translated): Yes, being there, done that, half an eon ago. And you got it wrong, see, this "y = i++;" is really "y = ++i". You should have abandoned C long ago.
Human: Ohhh... I see (damn!)
-- ;-)
Kuro5hin.org: where the good times never end.
You don't. You aim a beam of something else, protons, say (in the usual way with magnets) and then smash it into a carefully selected target. The collisions make lots of neutrinos (and other junk, but a few km or rock absorbs that) and they are travelling, pretty much, in the direction of the original beam.
Neutrinos interact so weakly that standing in the beamline would not cause you any harm. I have walked through the beamline of the NuTeV Experiment (while it was running). Not only that but a beam pointed at Super-K will not be a straight line, it will be more of a cone. At the surface in Japan, where the beam exits the earth, the size of the beam will be ~kilometers.
-- Bob
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
The collisions of protons with targets don't make neutrinos, they make pions. Charged pions can be directed magnetically; when they decay to muons, they create neutrinos and when the muons decay to electrons they create still more neutrinos. If the kinetic energy of the decay is small compared to the energy of the original beam, the neutrinos will be travelling in more or less the same direction as the parent particles.
Scientists restrict study to entire physical universe; creationist
And if they miss? They won't be seeing any neutrinos coming from the source accelerator. If they aimed at you, you'd never notice any more than you notice the millions of solar neutrinos streaking through your body every second like ghost bullets from an etherial machine gun. Hey, they don't even slime you...
Scientists restrict study to entire physical universe; creationist
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0
;)
Cute! However, the same logic can be applied to determine that 2=-2, 3=-3, 4=-4, ad infinitum, ad nauseum. In fact, using a third order mapping function you can show that three values (X1,X2,X3) are equivalent. Using a fourth order mapping function you can show that four values are equivalent. And so on . . .
And now you see the problem of trying to apply a tautology to mapping functions that are not homeomorphic -- i.e. "one to one" and "onto".
The function X^2=Y involves the loss of some information when mapping X to Y. There are two X values which will resolve to the same Y value. Therefore, the assertion that X1=X2 is correct since the inverse function is ambiguous as to which value of X was used to produce the given Y value. However, to assert that the value is zero you must impose the restriction on your mapping function that it is monotonically increasing or decresing -- i.e. that it is homeomorphic. X^2=Y is not.
Still, very cute