Ask Ethan: Does the multiverse explain our fundamental constants? | by Ethan Siegel | Starts With A Bang! | Mar, 2025

There are some 26 fundamental constants in nature, and their values enable our Universe to exist as it does. But where do they come from?

Here in our Universe, there are three major properties that have led to it unfolding as it has:

• the laws of physics that govern all of nature,
• the initial conditions that our Universe began with,
• and the values of the fundamental constants that apply to the particles, fields, and forces in our Universe.

Over time, this has led to our modern cosmos: full of atoms, stars, planets, galaxies, galaxy clusters, and a grand cosmic web. On some of those planets, life has arisen, with at least one instance of intelligent, technologically advanced life arising on a planet known very well to us: Earth.

But what if things were just a little different? Perhaps, even with the same laws of nature and very similar initial conditions, a version of our own Universe that possessed different fundamental constants could have turned out vastly differently than our own. So why does our Universe have fundamental constants with the values that they do? That’s what Pierre Louw wants to know, following up on…