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Beaming Neutrinos Through Earth?

Posted by michael on from the death-ray dept.

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."

2 of 33 comments (clear)

  1. Re:First impression by sigwinch · · Score: 3, Interesting
    The SuperKamiokande ... detector recently suffered an accident and is currently out of commission.
    "Accident" as in "half its photomultiplier tubes imploded". It will be some time before SuperK is back online.
    Will different densities affect how the neutrinos travel (making aiming a difficulty)?
    They ought to fly straight. (Not that that makes aiming easy!) The parameter of most interest is just the distance between the source and the detector. It is postulated that neutrinos can switch flavors in flight. The more distance they fly, the more chance they have of switching.
    --

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    Kuro5hin.org: where the good times never end. ;-)

  2. Re:First impression by TwP · · Score: 3, Interesting

    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 ;)