Can we travel faster than the speed of light?

Hello Steemians! How you doin? I am Rahul here and I am back again with another interesting, intriguing article related to science. In today's article, I will answer whether we can travel faster than light or not. Let's start.

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In movies like Star Trek, Star Wars we have seen spaceships which travel faster than light. But is it really possible to do the same? Well, the answer is not what you guys will be expecting. According to Einstein, you can't travel faster than light. Like you guys I was also heartbroken. But the question is why we can't travel faster than light.

One can deduce that we can't travel faster than light by different ways. Two of them are:

1. Mass increases as the velocity increases.
2. By travelling faster than light, one breaks the principle of causality.

Let's discuss both of them in detail.

Why increase in mass stops us from exceeding the speed of light?

According to Einstein, mass increases as the velocity of the object increases according to this equation.

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I won't go into derivation. If you want to know why is that? You can go here.

So what happens is as the velocity increases and gets close to the speed of light, the denominator in R.H.S increases and eventually it becomes zero. Because of that the mass of the object becomes infinity and the energy required for an object to reach the speed of light is also infinite. It is not possible for us to find an infinite energy source. 

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Therefore even the energy released in Big Bang is not enough to reach the speed of light. Since we can't even reach the speed of the light there's no point in talking about exceeding the speed of light.

Whats is principle of causality? How does it stops us from exceeding the speed of the light?

Principle of causality states that cause always precedes effect. In simple words behind everything there is always a cause. For example a bullet cannot come out of gun without pressing the trigger. A egg can't broke in the mid air without hitting the floor first. 

Now to understand why we can't travel faster than light let's take a similar example which explains it very well.

Let's assume that there is someone who can travel faster than the speed of light.

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 As in my previous article about time dilation I told you that when velocity of an object increases, time for that object runs slower and stops once its velocity is equal to the speed of light. So when that hypothetical person travels faster than the speed of light, time becomes negative for him i.e. now he is going in the past and he sees every event around him in reverse order. Now the problem is since he is in past now he can kill his father before he himself was born. Now what will happen? Since he killed his father he was never born but still he killed his father.

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How is that possible? If all this happens it breaks the principle of causality. Therefore theoretically we can't travel faster than the speed of light.

I hope you enjoy reading my articles. Do give a upvote and follow me to continue reading my articles.

In next article I will tell how we can travel "faster" than the speed of light.

References:

1. Why faster than light travel is impossible - Vigyan TV India
2. Causality(Physics) - Wikipedia
3. Why can't you go faster than light? - Fermilab
4. Mass in special relativity - Wikipedia

Signing off.....

@rahulk200013