Nutrinos and Energy
Name: Joseph R.
Gravitational potential energy converts to kinetic energy as a
particle approaches a gravitating body and returns to latency if the
particle climbs back out of the gravity well. It does not contribute
to the increase in mass of the body upon particle capture. But the
kinetic energy carried by a neutrino converts to rest mass if the
neutrino interacts with a nucleus. If a neutrino picks up kinetic
energy from the gravitational potential upon approach to a gravitating
body, and then interacts with a nucleus fixed in position on the
surface or undergoing centrifugal acceleration in an accretion disk,
then energy derived from the gravitational potential converts to rest
mass and this does contribute to the increase in mass of the body
upon particle capture. Is this not a violation of energy conservation?
What is the ultimate source of the rest mass energy derived from the
blueshift portion of the neutrino's total energy?
It is very important to realize that mass IS a form of energy. Albert
Einstein discovered this with his work in special relativity. It is the
basis of nuclear energy. When dealing with things on the level of atoms,
nuclei, and particles, it is possible to convert mass-energy into other
forms of energy. The reverse also happens. The gravitational potential
energy can become mass-energy through the relation E=mc^2. For a comet
coming in from space, gravitational potential energy (GPE) changes into
kinetic energy (KE). If it doesn't crash into anything, KE changes back
into GPE as the comet goes back out into space. For the neutrino coming in
from space, GPE again changes into KE. Because the neutrino joins with the
nucleus, a majority of the KE changes into mass energy. Some may remain as
KE of the new nucleus (with the joined neutrino). Still, total energy
before the event equals total energy after the event. You have to include
mass energy (mc^2) for things to balance.
Illinois Central College
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Update: June 2012