Natural Units and Heaviside-Lorentz Units in Theoretical Physics In theoretical physics, standard measurement systems like SI can make equations unnecessarily cumbersome with repeating constants. To simplify calculations, physicists use natural units and Heaviside-Lorentz units, which elegantly set fundamental constants to one. This approach not only streamlines complex derivations in quantum field theory but also reveals the deep underlying symmetries of nature. [INSERT DIAGRAM OF KEY CONCEPT HERE] 1. The Philosophy of Natural Units In the International System of Units (SI), we use distinct base dimensions for mass, length, and time (kilograms, meters, and seconds). However, nature provides its own fundamental scales. In high-energy physics, it is standard practice to set the reduced Planck constant (\(\hbar\(), the speed of light (\(c\(), and the Boltzmann constant (\(k_B\() to unity: \( \hbar = c = k_B = 1 \( By doing this, we fun...