4 ms·

I have the feeling that the second one.

• red_trumpet 3y ago
  That approach is not totally unjustified though. As an example, consider the complex numbers. They were first used to solve cubic polynomials, and people basically said "Let's pretend the square root of a negative number is something I can calculate with, obeying the general rules of calculus", and they did. Then they used those successfully to calculate real roots of cubic polynomials.
  • mdp2021 3y ago
    And where would you introduce "negative mass"? Involved, according to the presentation, in phenomena showing "creation of energy"?