I’m currently reading Max Tegmark’s book Our Mathematical Universe. In talking about the number of space and time dimensions we live in, he briefly mentions tachyons existing in one space dimension and three time dimensions.
I guess my questions are as follows:
What exactly are tachyons and how can they have imaginary mass?
How widely accepted are they in the science world?
What would reality with 3 time dimensions and one space dimension even be? Is it something the human mind can even imagine?