Simplify the following text for a Grade 11 native English-speaking person.
Original: They are detected by a theory called the seesaw mechanism which says that when sterile neutrinos are near other neutrinos ( tiny particles which are not affected by much ) , they increase their own mass by lowering the mass of the nearby neutrinos .
Simplified: The sterile neutrinos and ordinary neutrinos may also have Majorana masses .