Quantum Physics & Its Branches

Quantum physics cover

When it comes to Physics, most people relate it to either reaction or mechanics physics which is usually the field ruled by Sir Isaac Newton’s laws. However, there is another branch of physics which most of us are familiar with from sci-fi movies and documentaries about time travel, Quantum Physics. This is a whole different level of study and extremely difficult at that, where Newton’s laws don’t seem to matter, in fact, Newton’s laws are a consequence of it.

What is Quantum Physics?

In the past, physics was straightforward in a sense, it could be taught to anyone in small phrases like what goes up must come down. However, it changed from the previous century as scientists started to explore more about how our world and the universe works, they send probes to space to uncover our neighboring planets and experimented with tiny particles to see how they behave under certain circumstances. It is the latter that deals with atoms and other microscopic particles which is known as Quantum Physics or Mechanics. Basically, it quantifies, meaning the study that breaks down to the smallest particles in a vast body. For example, the ocean, as big as it may be with very complex molecules it is just a water molecule in the truest form.

The Copenhagen Interpretation

Einstein and Bohr

Albert Einstein and Niels Bohr at Paul Ehrenfest’s house.

Since we are on the topic of Quantum mechanics, we can’t ignore two contributing physicists in this realm, Albert Einstein and Niels Bohr. In 1927, a conference of great minds regarding quantum physics was to take place in Brussels, Belgium. Niels Bohr was excited to talk about his theory with Einstein, however, Einstein disagreed with his theory and later both of the scientists got into public debates which were later known as the Einstein-Bohr debate, and even to this day it is a valuable source of information for physicists, although both of them were friends and respect each other tremendously. So what was this theory that Bohr presented?

He said that a particle could exist in multiple states at once and once that particle is measured or observed, that particle starts existing in that fixed and specific state. Einstein said that this is not how particles behave saying that our observations have no effect on the particles as such, he even called it “spooky action at a distance”. They continued to debate over quantum entanglement over the course of months, each day one disagreeing with the other.

However, as we know it Niels Bohr’s idea finally won and is now considered the basis of quantum mechanics.

Also, one of the most bizarre and mind-blowing experiments was the double-slit experiment. It requires its own article, however, according to the previous physicist they said when observed, light acts like a particle in the experiment, and once it’s not observed it acts like a wave. Modern physics seems to deviate a little from this idea however, most say it is true.

Types of Quantum Physics


A representation of an atom.

Although it is a study that deals with minuscule particles, there are three main theories that deal with different types of forces. These are not branches of this subject as such. Even though gravity is one of the strong forces of nature, it only applies to object of a certain size, and in quantum mechanics, it just doesn’t function.

  • Electromagnetism: It is basically a study that focuses on the charge of bodies. It consists of two main components, electricity and magnetism. In the past, these two were considered as separate forces, however, as our understanding of physics expanding we found them to be one, thanks to Albert Einstein’s theory of relativity, though they do behave differently. When it comes to quantum mechanics, it explains how atoms are held together and continue to remain that way.
  • Strong Nuclear Force: This is one of the stronger forces as the name suggests. This force is the reason why the nucleus is stable in the center of an atom. It is a strong force that binds and holds quark clusters together to make subatomic particles, protons, and neutrons. To make it simple, we know that opposite charges attract each other while similar charges repel, now since atoms contain more than one proton that stays together, what keeps them together? The strong nuclear force. It is exponentially stronger than electromagnetism. Also, it is a contact-based force, meaning its effects are stronger when particles are in contact and start to get weaker as they move further apart.
  • Weak Nuclear Force: Finally, the last and the weirdest force among all. This explains the radioactive decay of an atom. Also, it should be noted that weak nuclear force has a preference for the spin of the particles and whether they are matter or anti-matter. It is an extremely weak force compared to the other ones.

Quantum physics deals with an extremely weird plane of existence. Whatever we know as accepted physics, all just disqualifies when going to that extreme level. As a former science student, it is both intriguing and complicated to wrap my head around. It is the type of study we should leave for experts.


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