However , neutrino flux does not perfectly track heat from radioactive decay of primordial nuclides .
Neutrinos do not carry off a constant fraction of the energy from the radiogenic decay chains of these primordial radionuclides .
However , neutrino flux does not perfectly track heat from radioactive decay of primordial nuclides , because neutrinos do not carry off a constant fraction of the energy from the radiogenic decay chains of these primordial radionuclides .