GraduatePhysics is a great channel, which host 1.6k videos, mainly on theoretical physics.
It's rather String-centric, for those interested in that line of thinking.
Two physicists, Arnab Priya Saha and Aninda Sinha from the Indian Institute of Science, inadvertently discovered a new formula for calculating π while working on string theory. Their findings were published in Physical Review Letters in January 2024.
This formula generates an infinitely long sum. What's remarkable is that it depends on a factor λ, which is a freely adjustable parameter.
Since there are infinitely many possible values for λ, Saha and Sinha have effectively discovered an infinite number of formulas for π. Interestingly, when λ approaches infinity, the equation corresponds to Madhava's formula discovered more than 600 years ago.