We can imagine a great variety of possible Universes that could have existed, yet even if we enforce the laws of physics as they are known, there are still fundamental constants required to determine exactly how our Universe behaves and evolves. Quite a large number of fundamental constants are required to describe reality as we know it, although many hope that a more complete theory will someday reduce the number needed. (JAIME SALCIDO/SIMULATIONS BY THE EAGLE COLLABORATION)

How Many Fundamental Constants Does It Take To Explain The Universe?

And, even with all we know, what still remains unexplained?

At a fundamental level, our Universe is made of particles, forces, interactions, and the fabric of space and time. Spacetime forms the ever-evolving stage on which the play of the cosmos unfolds, while the particles are the players. They can bind together, collide, annihilate, repel, attract, or otherwise interact according to the rules that govern the laws of nature. These pieces of information, along with the initial conditions of what was present in our Universe a long time ago, gives us almost everything we need to understand how the Universe came to be the way it is today.

The one missing ingredient? The fundamental constants that describe the strengths of all the interactions and the physical properties of all the particles. We need those pieces of information to understand the Universe quantitatively, and answer the question of “how much.” It takes 26 fundamental constants to give us our known Universe, and even with them, they still don’t give us everything.

The rest masses of the fundamental particles in the Universe determine when and under what conditions they can be created. The more massive a particle is, the less time it can spontaneously be created for in the early Universe. The properties of particles, fields, and spacetime are all required to describe the Universe we inhabit.(FIG. 15–04A FROM UNIVERSE-REVIEW.CA)