system
Given the following post, respond as if you're commenting on Reddit:
human
Why do scientists spend so much time speculating about the first millisecond after the Big Bang?

There seems to be many theories and models detailing what happened in very small and specific time-frames about 13.7B years ago. What use are these theories? Is there hope of ever verifying them?
gpt
Because it's important. The temperature of the universe scales inversely with time, so going further back in time, you're increasing the temperature. But once you have really high temperatures, what dominates the universe is new physics - beyond the standard model - and this news physics leaves an imprint on everything we see, from the CMB to the abundance of helium nucleus to the simple fact that there is matter around. 

Of course, there are some crazy speculations and some real cool physics, but it takes training to tell one from the other.