How to move faster than light…Without even moving.

One of the reasons why humans have become an advanced species in this harsh planet is our ability to travel. Traveling has enabled humans to inhabit some of the remotest places on Earth. Humans are nothing but fragile brains capable of moving through space. So when it comes to the speed at which humans can travel, is there a limit?

Turns out that the very fabric of reality has some strict rules about speed. It is as if there is a cosmic cop who is ever vigilante, always making sure that nothing goes beyond the speed of light, and light is very fast. It is the fastest thing in this universe. But is it enough to satisfy our requirement? No. When it comes to the unimaginable size of the universe, light is unbelievably slow.

By the time you’ll be done reading this article (if you read it completely), light would have traveled only the distance between sun and earth. And sun is the closest stellar object to us. If we made a spaceship that could travel at the speed of light (which physics does not allow), it would take more than 4 years to travel to Alpha Centauri, the next closest stellar object to earth. Leave earth during the FIFA World Cup and you’ll each A. Centauri on the next FIFA World Cup. But what if we don’t find anything on that star. What if we embark on another, much longer journey?

Traveling Light

The star Betelguese, which represents one of the shoulders of the constellation Orion is 642 light years away from earth. If someone left earth before Christopher Columbus found America, traveling at light speed, he/she would reach Betelguese this year. So traveling at the fastest speed possible (which is prohibited) is very slow. But what if we could cheat the very fabric of spacetime and travel faster than the speed of light? It can be done, theoretically.

An Alcubierre Drive or the Alcubierre metric is something that you maybe hearing for the first time. But look into the world of sci-fi and you’ll see this very concept used frequently. Warp drive may ring a bell in your mind, especially if you are familiar with Star Trek. The “warp” in the term explains the whole working of an Alcubierre drive. The warp drive doesn’t move, strictly speaking. It just makes the space around it warp in a way that changes its position. Don’t worry, I’ll explain further down the article why Warp drives are possible and much better than traveling at near light speeds. And I’ll also explain why warp drives could be a ludicrous idea, only to live in the world of theoretical papers and science fictions, and in articles like these.

Imagine

Let us, for a small portion of our time together, break the laws of physics and travel to the future, you and I. Let’s visit a place where we have created Alcubierre drive. Like there is FTTH (Fibre To The Home) tech for internet connection, there is a FTL travel option. FTL stands for “Faster Than Light” travel. We go to the Spaceport (like an airport) to take the Intergalactic express. There would be an option for interstellar travel, but let’s go to a different galaxy rather than a different star. Remember, this warp travel would be more like a train than a airplane. I’ll explain why in the later section.

Our travel time is around 3 hours and since electronic devices won’t work inside the warp drive, we take a book. Maybe Murakami or Kafka, or more apposite would be Douglas Adams. The journey is expensive, so we choose to travel light (and faster than it). We pack our bags, reach the Spaceport and get all the documents verified. But since this is our first time traveling, we go for a small briefing about how the Alcubierre drive would work. This is how the drive would work.

A Sprinkle of Fiction.

“Welcome to BierreX” says the guy in a blue spacesuit who would be our guide for the ride. “This is the only company to offer warp travel. We offer the most comfortable and safest way to travel faster than light. The warp technology allows us to cross distance that would take millions of years by fuel-based rockets.”

“How does the warp drive work?” Asks an inquisitive passenger, trying to ensure that the people in charge know what they are doing.

“That’s a great question” the man clad in blue spacesuit says, as if he was expecting this question. This is what he explains.

The concept of a warp drive, as shown by Miguel Alcubierre, was theoretically possible as it fit in well with Einstein’s Special Relativity and did not violate any laws. And after the confirmation of gravitational waves by LIGO, it was very clear that space is like a fabric. It can be distorted by high energy/mass. Everything with mass bends spacetime. But to make a warp drive move, we needed something more than large mass, we needed something…exotic.

Exotic mass is something that is not easily available in out universe. These include dark matter, anti-protons, positrons (anti-electron), etc. The exotic matter needed for Alcubierre drive to work is negative mass. Negative mass is just like normal mass, but it is exactly the opposite. So if you push a ball that is made of negative mass away from you, it will roll towards you. That is why it is…exotic.

The Warp drive uses negative energy density as the fuel for the engine. The place where the passengers sit is covered inside a “bubble” that protects them from the extreme energy and relativistic time dilation. To the passengers sitting inside, it feels as if they are not moving at all. And in a way, that is exactly what’s happening.

Instead of moving through space, the drive moves space itself. There is an illustration to aid the explanation. Imagine you are sitting in the middle of a lightly elongated spring. What the warp drive does is, it stretches the distance between you and the source and compresses the distance between you and the destination. This distortion of space-time causes the warp drive to move way faster than light, without breaking any laws.

The “bubble” which is actually shaped more like a donut (as this shape is energy efficient) is necessary to remove the relativistic time dilation. Remember that you are not warping through space, but spacetime. Time is relative. So fifteen minutes in the warp drive for you could be 10 years for the people on earth. Hence, we cannot break the “bubble.”

Beginning The Journey

We are all set for our journey to begin. Everything is all set, we have had all the explanation that we needed. You take a look at the pricing of the tickets. Traveling five times the speed of light (written as 5c) is more expensive than two times the speed of light. Seems fair. But you notice something peculiar. The costliest ticket takes you not to a farther distance, but into the future. This is where our bubble breaks and so does our BierreX Alcubierre drive.

That ticket to the future is where all theoretical concepts of the warp drive fails. There is a concept called “Chronology Protection Conjecture” proposed by Stephen Hawkins. It somewhat says that you cannot disturb the order of things in time. Future turns present and then into past. But with the most expensive ticket for the warp drive, you can travel to the future.

There are a lot of concepts that need extensive explanation and ofcourse that cannot be given here on this article. The most important is the concept of light cones. I’ll state the gist of it. But there are a lot of maths involved in it.

Information travels at the speed of light. Anything that happens, the information about it travels at the speed of light. Let’s say that the sun just bursts. Since light takes eight minutes to reach earth, we would have no idea about the sunburst for eight minutes. For Betelguese? We won’t be able to know about it for 642 years.

"Time Travel? Not under my Watch" - The Universe.

The warp drive offers to travel multiple times faster than light. So if you witness the burst of the star Betelguese and decides to take a warp drive express to earth, ten times faster than light. After reaching earth, not only he would have traveled an absurd amount of distance, but also into the future, since he is aware of a future event that hasn’t happened yet. This is the violation of chronology protection conjecture.

The chronology protection conjecture is still in the murky area of being a concept, hence the term conjecture. It could be that there is no such thing. But scientists are betting on it. They believe that some other law or an aspect of the universe would prevent time-travel. So the chances of you or me boarding the warp drive is almost zero. But even if time-traveling was not a issue, there is a plethora of problems that the universe has imposed on us when it comes to traveling faster than light.

Not a Plane, but a Train

The reason why I said that a warp drive would be more like a train than a airplane is because the drive needs an infrastructure to operate. We are talking about warping spacetime with enormous amounts of energy. The energy the warp drive would be taking with it when it stops at the destination would be enough to destroy the destination, along with the galaxy it is in. And to make an infrastructure would defeat the purpose of warp drive. It is like calling a person on their cellphone. But you have to physically go to that person to ask him to receive the call.

Possibility?

NASA is working on a similar project that would create something like a warp drive but in molecular scale. The project, undertaken by Eagleworks division may achieve some success and the whole thing is just to see if theory can be turned into practicality. A full scale warp drive is probably thousands of years away in time, if possible at all. But I refrain myself from making any bold claims about the achievement of humans. The New York Times in 1903 stated that humans making a flying machine (airplane) is possible in about one to ten million years. The very same year Wright Brothers built the plane.

The invention of the wheel enabled us move faster on land. Invention of airplanes allowed us to move to different fragments of land. The rocket took us to another land, far into the space. Now we are looking for a faster and better way to move through nothingness of space, just to find some new land. Like the early humans who roamed to find some better land, we are doing the same thing, just in a different way.