I really like this. These fundamental concepts are not often discussed deeply like this at one shot. Bravo. Well organized.

Fantastic explanation at a good pace. Very helpful to get clarity on so many things in one go, at atomic level

Im obsessed with this subject, and this hit a perfect depth and pace. Wonderful

Quite a comprehensive overview from fundamental particles to the Cosmo into our very own existence and after life. More importantly, to me that is, I'm glued to the screen and surprisingly understand. Great job and keep up the good work. From Hong Kong

7:00 The Big Bang doesn't explain the two questions that I think are the most mind boggling questions possible.

21:00 Having two identical atoms in the same state is not only unlikely it is fundamentally impossible under our current understanding of physics except under extremely specific conditions like those that form a BEC. This is what the Pauli Exclusion Principle is telling us that two particles can not exist in the same location in Hibert Space. Since Atoms are made of the Quantum particles this theory is discussing achieving the same quantum states needed to create two identical atoms is impossible. There are Bose Einstein Condensates( BECs) which achieve something along these lines at extremely low energies but when this happens all the particles start to behave as one single unified Wave function, almost like, Quantum Entangling all the Quarks that make up the cloud of Atoms such that they form one unified Wavefunction acting as a single particle.

Thank you, I really think I learned something, ...I think. Highly interesting and informative. Now, I'll just have to give myself time to ponder these thoughts and give my molecules time to calm down and return to vibrating harmonically again, as they are in a very excited state right now. Great stuff!