Category Archives: Equations

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

Q: What is the three body problem?

Physicist: The three body problem is to exactly solve for the motions of three (or more) bodies interacting through an inverse square force (which includes gravitational and electrical attraction). The problem with the 3-body problem is that it can’t be … Continue reading

Posted in -- By the Physicist, Astronomy, Equations, Philosophical, Physics | 29 Comments

Q: Why does light choose the “path of least time”?

Physicist: Light travels at different speeds in different materials.  When you shine a beam of light from one material into another (like from air to water) it bends in such a way that the path it takes from one point … Continue reading

Posted in -- By the Physicist, Equations, Geometry, Logic, Physics | 27 Comments

Q: What are integral transforms and how do they work?

Mathematician: If you have a function f(x) and a function k(x,s) then you can (as long as the product of f(x) times k(x,s) is integrable on the set X) always form another function of a new variable s as follows: … Continue reading

Posted in -- By the Mathematician, Engineering, Equations, Math | 9 Comments