Time Travel Part 2

NOTE : If you haven’t read the 1st part please read the 1st part then read this part….

Click here to read the 1st part…

The Science of Time Travel: Moving Forward to the Future but Not to the Past

Why Can’t We Go Back to the Past?

From a scientific perspective, traveling to the future is possible, but going back to the past isn’t. The main reason is that time flows forward, and this natural progression of time prevents us from moving backward. Additionally, the concept of paradoxes, hypothetical situations that could arise from traveling to the past, stops us from reversing time.

We know that time began right after the Big Bang, and ever since, the universe has been continuously expanding. But what force causes this expansion? The answer is attributed to “dark energy”, an invisible force responsible for the expansion of space. Time flows forward over this expanding space at a constant pace. In simpler terms, because space is expanding forward, time also progresses forward, preventing us from moving backward.

Think of it this way: if a rope is tied to a forward-moving train, no matter how hard you pull, you cannot bring the rope back. Similarly, for time to reverse, the space that is expanding forward must begin to contract. Scientifically, this might only happen if the universe undergoes a “Big Crunch”, where the expansion of the universe reverses, causing space to contract. If this happens, time might also reverse, and we could potentially witness past events. But until the Big Crunch occurs, returning to the past from the present is impossible.

How is It Possible to Travel to the Future?

If you can move at the speed of light, you can travel to the future! When you travel at light speed, time stops for you while continuing to flow normally for everyone else. The longer you move at light speed, the less you age compared to those who remain stationary. How much younger you are will depend on how long you’ve been traveling at that speed.

Time Dilation and the Theory of Relativity

One experiment suggests that if you could create a train capable of traveling at 90% of the speed of light, and it traveled around the Earth for a week with passengers onboard, those passengers would age 68 years less than people on Earth. This illustrates how time dilation allows you to travel into the future by moving at extremely high speeds.

The Event Horizon of a Black Hole

An “event horizon” is a boundary around a black hole where the gravitational force is incredibly strong. As we mentioned earlier, gravity has a significant effect on time. When time passes near an event horizon, where gravity is intense, it slows down drastically.

However, time on Earth continues at its usual pace. For instance, if you spent one second near the event horizon of a black hole, several hours could pass on Earth. So, if you spent just one minute near the event horizon and returned to Earth, you might find that 10–15 days had passed on Earth.

The Challenge of Returning from an Event Horizon

While this would allow you to travel into the future, returning from the event horizon is practically impossible because the gravitational pull near a black hole is so strong that nothing can escape.

Wormholes: Tunnels Through Space and Time

During the study of black holes, scientists proposed the concept of “white holes”, which are thought to be connected to black holes through a tunnel called a “wormhole”. A wormhole is essentially a shortcut through space-time, connecting different parts of the universe.

According to the theory of relativity, when something is sucked into a black hole, it might pass through a wormhole and emerge from a white hole, possibly in another part of the universe or even in a different time.

Scientists are currently exploring the possibility of creating an artificial wormhole. If successful, we might be able to travel to distant places, like Alpha Centauri, in just a few minutes.

Are We Already Time Travelers?

You might be surprised to learn that, in a way, we are all constantly traveling through time. Many people think time travel is purely fictional, but in reality, we are always moving forward in time. Here’s an example: if your watch shows the time as 12:00 noon, and after a while you look again and it’s 12:15, you’ve traveled 15 minutes into the future.

While this is a simple instance, the same principle applies in more extreme situations, such as high-speed travel. For example, people who travel by train or airplane experience a very tiny time dilation compared to those who stay on the ground, even though it’s only by a few femtoseconds (one-millionth of a billionth of a second).

This is so small that we can’t perceive it, but it’s measurable. Similarly, an astronaut on the International Space Station (ISS) aged 0.02 seconds less than people on Earth.

The Train of Time

We are all constantly moving forward in time, leaving the past behind as we journey into the future. Imagine time as a moving train that began its journey with the Big Bang. The tracks are the expanding space, and the train is always moving forward along them. Whether the train moves slowly or quickly, it never reverses. Time, much like this train, never moves backward.

It’s important to note that all of time’s relativity applies only to our perspective. Time itself is always moving forward at its own pace, independent of our experiences.

Think of time as a train, and we are the passengers. We board the train at birth and ride until we reach our final destination: death. At that point, we exit the train and are lost to time forever. However, some people, like Einstein and Newton, remain alive in our memories because of the incredible contributions they made during their lives. Wouldn’t you like to leave a lasting legacy for future passengers on the train of time to remember you by?