"It does. A normal body possessing energy tends to dissipate that energy by transferring the excess to other bodies possessing less than it does. A body possessing negative energy would demand that energy be applied to it in order for it to acquire a state of energy equilibrium.
"The positron, according to Dirac, is a state of negative kinetic energy which is satisfied only when the energy of an electron is applied to it. In the process known as 'pair-production', where hard gamma strikes matter and releases an electron and a positron, it is actually a case of separating the electron from its positron, leaving in effect a 'hole' in the level of energy.
"It is a man whose bills are not paid but are merely covered by written and certified checks. Send away one check and you have a debit in the man's account. The positron is satisfied very quickly, however, since there is a large excess of free electrons to fall into place.
"These cancel the positron—and that process produces hard gamma rays again—of the same energy content as required to cause the 'pair production' in the first place. About one million electron volts plus," he added.
She hesitated a moment.
"Now—about this negative mass," she said.
"Simple," he said. "Very simple. A negative mass is the only thing that can exceed the speed of light. Similarly negative energy is the only kind that can propagate in excess of light. So now let's juggle equations until we can reproduce the same."
Rhine nodded, picked up a pencil and then looked at him expectantly.
"Put down," he said with a smile, "the first equation that ever told the truth about the relationship between mass and energy. Energy 'E' equals Mass 'M' times the squared speed of light, 'C2'."
"And from there?"