After seeing the first few minutes of [Veritasium’s](https://www.youtube.com/watch?v=Kp_kqamkYpw) video on how half of the baryonic matter was yet unobserved until recently, he mentions how the ratio of deuterium and helium and other elements were all formed within the first 20-ish minutes after the big bang but also how with around 10 seconds the universe had cooled significantly.
How is that sort of timescale measured accurately when the big bang happened so long ago, especially when even some modern history events cant be traced down to hapening within an exact year sometimes?
In: Physics
Using physics you can find out what something will do before it does it. With what we know about physics we can safely assume that different events would have happened at specific times.
The reason events here on earth, more specifically historical events cant be properly timed and dated as accurately is because it isnt all physics.
If we know the Greeks began marching on Troy on Sept 1st, at noon, we dont have enough information to say when they got there. There are a lot of factors in historical events that can make placing it on a timeline difficult. Soldier 1 has the date Sept 1st in his journal. Soldier 2 has Sept 3rd. Soldier 3 says they went in early September but by a different route. And some villager says the Greek army passed her home at the date and time they were allegedly mid battle.
We have 4 accounts here, who is to say which one is correct?
So without video proof, all we have are the accounts of people who are long dead, and people make mistakes, and lie as well. Physics doesn’t.
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