Antonyms for the phrase "comparing notes" could include ignoring each other's viewpoints, not communicating or collaborating, keeping information to oneself, or having divergent perspectives. These antonyms suggest a lack of unity, cooperation, and openness to share information or ideas. When individuals do not compare notes, they may miss important details, perspectives, or insights that others might have. In a group setting, not comparing notes can lead to miscommunications, misunderstandings, and conflicts, as everyone may be working with different assumptions and incomplete information. Therefore, it is essential to foster an environment where comparing notes is encouraged, valued, and practiced regularly for effective communication and collaboration.