Four forces of the universe

Four forces of the universe

In modern particle physics, there are four known fundamental interactions or "forces" that govern all structure and motion in the universe as we know it. These forces are classified as "fundamental" because there is still no scientifically complete way to otherwise describe them. The four forces are gravitation, electromagnetism, strong interaction, and weak interaction. Often they are referred to as the gravitational force, the electromagnetic force, the strong nuclear force, and the weak nuclear force.

Gravitation is the weakest of all the forces but acts over infinite distances in the universe. Due to this, gravity is not really a factor in particle physics. Notably, however, it is the only fundamental force that acts on all particles that have mass. Also, nothing can "cancel" the effect of gravity because it only attracts.

Electromagnetism is the force that acts inside and between electrically charged particles. It can be attractive or repulsive, and it only affects pieces of matter carrying electrical charge. Like gravity, the electromagnetic force has infinite range, but it is vastly stronger.

Strong interaction only operates at the atomic scale acting upon elementary particles. It is the strongest of all the fundamental forces, but it is very short-ranged. The strong nuclear force is what acts between protons and neutrons within an atom's nucleus, and is responsible for holding the nuclei of atoms together. Without it, the nucleus could not exist.

Weak interaction is responsible for radioactive decay. Like the strong nuclear force, it only operates at the atomic scale. It has a very short range and, as its name suggests, is very weak. The weak nuclear force is stronger than gravity over its short distances.

These four fundamental forces all play a part in making the universe what it is today!

The molecular biologist (and author) Michael Denton makes a very interesting point about the universe's fundamental forces in his book, Nature's Destiny. According to Denton, the universe was created and specifically designed to make human life possible.

Here is the interesting point Michael Denton addresses:

"If, for example, the gravitational force was a trillion times stronger, then the universe would be far smaller and its life history far shorter. An average star would have a mass a trillion times less than the sun and a life span of about one year. On the other hand, if gravity had been less powerful, no stars or galaxies would have ever formed. The other relationships and values are no less critical. If the strong force had been just slightly weaker, the only element that would be stable would be hydrogen. No other atoms could exist. If it had been slightly stronger in relation to electromagnetism, then an atomic nucleus consisting of only two protons would be a stable feature of the universe-which would mean there would be no hydrogen, and if any stars or galaxies evolved, they would be very different from the way they are. Clearly, if these various forces and constants did not have precisely the values they do, there would be no stars, no supernovae, no planets, no atoms, no life."