For a long time, this meant that to test BBN theory against observations one had to ask: can all of the light element observations be explained with a single value of the baryon-to-photon ratio?

• 长久以来，这意味著在太初核合成理论和观测的对抗上，你必须问：所有对轻元素的观测能否解释重子对光子的唯一比率？