Wormholes

What are wormholes?

The wormholes are one of the possible solutions to the equations of the General Theory of Relativity. They are the shortcut used to travel significant distances faster than the speed of light. They are due to the wrapping of space-time to a great extent! They are not only used to travel to two far apart points in one universe but can also make bridges between two different universes. Their appearance is very similar to that of black holes. You can see the other part of the universe in which one mouth of the wormhole lies from the other mouth of the wormhole which lies in a different part of the universe, for example, you can see the surroundings around your house from your window and vice-versa.

Formation :

We don’t know much about how wormholes are formed, but we have certain theories which are mathematically correct, so it is not necessary that they exist because every mathematically correct thing can be or cannot be found in nature.

One of which suggests that they are formed when a black hole(a body that sucks up everything near it, including light ) and a white hole (a body that spews out the matter with such a huge force that nothing can enter that region) gets attached via a tunnel.

Do Wormholes exist?

We have only seen them in sci-fi movies like Avengers, Interstellar, etc, but don’t have evidence of their existence to date. Their existence is only up to mathematical solutions of the general theory of relativity. Their existence is highly doubtable because they are very unstable because of their high gravitational forces which do not allow wormholes to keep their mouths or entry/exist and tunnel open. We require exotic matter which has a negative mass, therefore having negative energy to stabilize them. The negative mass overcomes the gravitational forces and hence keeps the mouths and tunnels of a wormhole open. Having said that, the negative mass or negative energy is also limited to a theory and we haven't detected such particles and even we don’t have advanced science or technology to create such particles. But there might be another problem regarding traveling because travel of normal matter through a wormhole could make it unstable and it may collapse to form a singularity and ultimately leads to the formation of a black hole. But we may overcome these problems in the future and who knows, we might be able to go through one. A few theorists believe that the black hole at the center of our galaxy is actually a wormhole!

Wormholes and nature :

There’s a possibility that a wormhole can be formed by nature. In the early period just after the big bang, a wormhole can be formed due to quantum fluctuation of space-time. But, these wormholes are so small and unstable that they can collapse within seconds and therefore, they only exist for seconds or even less. This makes it next to impossible for us to detect a wormhole.

Some of the fascinating ideas about wormholes:

1. Its relation with quantum mechanics :

Terminology to understand this concept, Quantum Entanglement: it is the most fundamental part of quantum mechanics. It is a link between any two entangled particles through which these particles communicate faster than the speed of light, no matter how far apart these two particles are. When one particle is affected, then its effect can be noticed on another particle, therefore both are dependent on each other.

Recently, a group of physicists including Leonard Susskind explained that if we entangle two black holes and later on separate them will lead to the formation of an Einstein-Rosen bridge or wormhole through which they can communicate and pass the information faster than the speed of light, now if this idea is true than our smooth space-time fabric may be formed due to entanglement of tiny space-time fabric’s chunks. This leads us to conclude that gravity isn’t the most fundamental thing on which our universe is shaped but these entanglements are! Building our space-time on the concept of entanglements will be a crucial step in resolving the laws of quantum mechanics and general relativity. This is what makes this idea amazing!

2. Time travel :

NOTE: We have kept the time very simple to avoid complexity.

Diagram description: Assume that the wormhole is stable, travel-friendly, and controlled by two persons A and B. There is a mouth of a wormhole, say it mouth A, which lies in front of person A’s house, and another mouth, call it mouth B lies within the spaceship in which person B is traveling. The spaceship travels at around the speed of light. Now, the spaceship travels for 2 hours at approximately the speed of light and comes back to the Earth.

Thought-experiment :

• At the start of a journey, both mouths of wormholes are linked with each other, since they have the same time ellipse. So, these mouths can be used as windows to a spaceship or person A’s house.

• When the spaceship completes half of its journey, then according to relativity theory, person B and mouth B have just grown 1 hour older, and Earth including person A and mouth A has grown 1 year older! This is because Earth was at rest while person b and mouth B will experience slow time rates as compared to Earth’s time. Now, if person B enters and travels through mouth B at this moment, then he/she will emerge from mouth A when 1 hour is spent relative to the Earth after the journey of a spaceship began. Here, relativity in time is a key thing to focus upon to understand and imagine this thought process. Why doesn't person B arrive on Earth when the time spent there is 1 year? This is because when a mouth B has just grown 1 hour younger along with a spaceship after the start of the journey, then mouth A has grown a year older along with the Earth after the start of the journey. So, due to mouth A having traveled far ahead in time w.r.t mouth B, therefore mouth B will link with mouth A in the past w.r.t Earth(1 year older after the start), it(mouth A) has only grown 1 hour older after the start. So, in traveling through a wormhole, you will always travel through the mouths having the same local time. This is how the nature of wormholes is!

• Now, when the spaceship has completed its journey of 2 hours and landed just around person A’s house, then Earth, person A, and mouth A, all have grown older by 2 years after the start although person B has traveled only for 2 hours. Now, person B is in the Earth’s future relative to him/her because of time dilation due to traveling at high-speed relative to earth. But, if person B jumps inside the mouth B in a spaceship, then he/she emerges from mouth A which is 2 hours older after the start, which is Earth’s past. So, now it's person B’s choice to whether remain in the Earth’s future or to go back to Earth’s past, both relative to person B!

• It shows us that wormholes not only connect two different places but also link their time. So, with the help of this thought process, we can travel in time relative to us without breaking the laws of physics. This is what makes this thought process marvelous!