The paper did not explicitly predict a new particle, but referred to the interchangeability of positive and negative electrons as solutions to his equation as "difficulties" that were "unresolved".
He referred to the issues raised by this ambiguity as "difficulties" that were "unresolved". The paper did not explicitly predict a new particle, but did allow for electrons having either positive or negative energy as solutions.
The paper did not explicitly predict a new particle, but did allow for electrons having either positive or negative energy as solutions. He referred to the issues raised by this ambiguity as "difficulties" that were "unresolved".
The paper did not explicitly predict a new particle, but did allow for electrons having either positive or negative energy as solutions. He referred to the issues raised by this ambiguity as "difficulties" that were "unresolved".