Fine-tuned universe

The characterization of the universe as finely tuned intends to explain why the known constants of Nature, such as the electron charge, the gravitational constant, etc., have the values that we measure rather than some other (arbitrary) values. According to the "fine-tuned universe" hypothesis, if these constants' values were too different from what they are, "life as we know it" could not exist. In practice, this hypothesis is formulated in terms of dimensionless physical constants.