The Forces of the Universe
Written By: Aardash Srinivasan
We are constantly affected by the forces of the universe. Without these forces, the universe wouldn’t exist today. Atoms wouldn’t exist because of both the strong and weak forces, which means we wouldn’t be able to exist. The Earth wouldn’t exist because gravity wouldn’t have pulled in the dust and gas to make it. The solar system wouldn’t exist because gravity wouldn’t act on all planets and keep them in orbit. The Milky Way wouldn’t exist because gravity is needed to keep the galaxy together. The universe wouldn’t be rapidly expanding after the Big Bang, and the Big Bang wouldn’t have even happened. In this article from Science Rewired, we will take a dive into the 4 fundamental forces of the universe.
The 4 fundamental forces of the universe are the strong force, the electromagnetic force, the weak force, and the gravitational force. These forces are the entire reason the universe exists, and they explain how the universe works.
The first force is the strong force, which is the strongest out of the four. This force happens between the subatomic particles in the nuclei of atoms. Protons and neutrons are made up of quarks, and the strong force groups the quarks together in little clusters which make up the subatomic particles. The forces responsible for the strong force are called the color forces. These are responsible for making the strong force the strongest fundamental force of the universe. Even though this force is the strongest of the four, it acts over very small distances (across the length of the nucleus of an atom). The other forces are stronger for longer distances.
The second force is the electromagnetic force. This force is the second strongest force of the 4 fundamental forces. This force happens between particles that are electrically charged. It can act as attractive or repulsive. For example, protons and electrons are attracted to each other, while 2 protons are repelled from each other by the electromagnetic force. Electric charges are responsible for the electromagnetic force, just like color forces are responsible for the strong force. The electromagnetic force is 100 times stronger than the strong force, but can be applied over longer distances.
The third force is the weak nuclear force. This force is the third strongest force of the 4 forces. The weak force happens across the shortest distances of all the 4 forces. It happens around 100 times less than the distance of the strong force, and it is 1 million times weaker than the strong force. Protons and neutrons are made of 2 types of quarks. Up quarks and down quarks. The weak force has the strength to change one quark into another. If it changes a neutron to a proton inside an atomic nucleus, it can convert the element into a different element because it changes the number of protons inside the nucleus. However, this force is still stronger than the gravitational force.
The gravitational force is the weakest of the 4 forces, but it is the one that we see the most in our day-to-day lives. The gravitational force is the attraction between 2 objects with masses. Any object with a mass exerts a gravitational force with every other object with a mass in the universe, no matter how far the 2 bodies are apart. Gravity is the reason our solar system exists. It works across infinite distances, which is the basis of the formation and structure of the universe. However, while it acts across infinite distances, it is the weakest of the 4 fundamental forces of the universe, as it is 100 trillion trillion trillion times weaker than the strong force.
For a long time, scientists have been struggling to unite the 4 forces to create our understanding of the universe (a unified field theory). They have found a way to unite the strong force, the weak force, and the electromagnetic force, but they are still yet to figure out how to unite gravity with the other 3 forces. As time goes on, it won’t get easier to solve the theory, but when we figure it out, it will explain a lot and fill a bunch of the gaps in understanding the universe.
