So far combinations beyond weak forces and electromagnetic fields are only a goal of particle physics and cosmology.
As the expansion continues, more familiar particles like protons, neutrons, electrons, and photons begin to appear.
Initially, there are both matter and antimatter particles.
The matter particles are found today, whereas the antiparticles were annihilated by matter prior to the time of nucleosynthesis.
Associated with these forces are different classes of particles.
The strongly interacting particles are composed of two or three quarks and are known as hadrons.
The weakly interacting particles are known as leptons and include the electrons, muons, tau particles, and their associated neutrinos.
The hadrons include the baryon subgroup that includes protons and neutrons.
The search for the origin of our universe and its contents, including the Earth and its living organisms, is a fundamental object of human curiosity.
Following the discovery by Hubble that the galaxies of the universe all recede from each other, a simple projection back in time allowed Gamow to estimate that the universe must have originated from a very dense and hot condition that allowed the formation of the chemical elements out of more elementary constituents.