Category Archives: Math

Q: What are chaos and chaos theory? How can you talk about chaos?

Physicist: Chaos theory, despite what Jurassic Park may lead you to believe, has almost nothing to do with making actual predictions, and is instead concerned with trying to figure out how much we can expect our predictions to suck. “Pure … Continue reading

Posted in -- By the Physicist, Math, Probability | 11 Comments

Q: What is the Riemann Hypothesis? Why is it so important?

Physicist: To non-mathematicians this seems like a whole lot of fuss over nothing. There’s a function called the Riemann Zeta function, denoted ““, that’s defined for complex numbers (that is, you can plug in for example, and it’s totally fine).  … Continue reading

Posted in -- By the Physicist, Equations, Math, Number Theory | 12 Comments

Q: Why does the entropy of the universe always increase, and what is the heat death of the universe?

Physicist: The increase of entropy is just how a scientist talks about the fact that the universe tends to do the most likely thing.  For example, if you throw a bucket of dice you’ll find that about a sixth of … Continue reading

Posted in -- By the Physicist, Entropy/Information, Physics | 61 Comments

Q: How are imaginary exponents defined?

The original question was: How do you do xi (x to the i power), and how on Earth was it developed?  There isn’t really anything to base xi on from previous rules of exponents as it is a completely new … Continue reading

Posted in -- By the Physicist, Conventions, Equations, Math | 36 Comments

Q: What is “spin” in particle physics? Why is it different from just ordinary rotation?

Physicist: “Spin” or sometimes “nuclear spin” or “intrinsic spin” is the quantum version of angular momentum.  Unlike regular angular momentum, spin has nothing to do with actual spinning. Normally angular momentum takes the form of an object’s tendency to continue … Continue reading

Posted in -- By the Physicist, Equations, Math, Particle Physics, Physics, Quantum Theory | 77 Comments

Q: What is Bayes’ rule and how do I use it to improve my life?

Mathematician: Bayes’ theorem in one of the most practically useful equations coming from the field of probability. If you take its implications to heart it will make you better at figuring out the truth in a variety of situations. What … Continue reading

Posted in -- By the Mathematician, Equations, Math, Probability | 8 Comments