The discussion centers on the implications if Einstein's E=mc² were proven wrong, suggesting that such a scenario would fundamentally disrupt our understanding of physics. Participants argue that violating this principle would necessitate a complete overhaul of both special and general relativity, as these theories are deeply rooted in its validity. Questions arise about the nature of time and space if speeds beyond light were achievable, with concerns about the consequences for established laws of physics. The conversation also highlights the speculative nature of the topic, questioning its educational value and relevance to current scientific understanding. Overall, the consensus is that challenging E=mc² would lead to significant and potentially catastrophic changes in our comprehension of the universe.