Is it Possible, are we ready for it yet, have we reached the verge of science, can we travel back or forward in time.These are probably the questions that are gonna be answered today.
lets first discuss what is time ?
What is time ?
Time is the indefinite continued progress of existence and events that occur in apparently irreversible succession from the past through the present to the future.Time is a component quantity of various measurements used to sequence events, to compare the duration of events or the intervals between them, and to quantify rates of change of quantities in material reality or in the conscious experience. Time is often referred to as the fourth dimension, along with the three spatial dimensions.
Can we travel in time ?
By the way we all do time travel. We all move forward in time, for example During the last year, I’ve moved forward one year and so have you. Another way to say that is that we travel in time at the rate of 1 hour per hour.But the real question is can we travel in time faster or slower than “1 hour per hour”? Or can we actually travel backward in time, going back, say 2 hours per hour, or 10 or 100 years per hour?.
It is mind-boggling to think about time travel. What if you went back in time and prevented your father and mother from meeting? You would prevent yourself from ever having been born! But then if you hadn’t been born, you could not have gone back in time to prevent them from meeting.
Special theory of relativity and time
The great 20th century scientist Albert Einstein developed a theory called Special Relativity. The ideas of Special Relativity are very hard to imagine because they aren’t about what we experience in everyday life, but scientists have confirmed them. This theory says that space and time are really aspects of the same thing—space-time. There’s a speed limit of 300,000 kilometers per second (or 186,000 miles per second) for anything that travels through space-time, and light always travels the speed limit through empty space.
Special Relativity also says that a surprising thing happens when you move through space-time, especially when your speed relative to other objects is close to the speed of light. Time goes slower for you than for the people you left behind. You won’t notice this effect until you return to those stationary people.
Say you were 15 years old when you left Earth in a spacecraft traveling at about 99.5% of the speed of light (which is much faster than we can achieve now), and celebrated only five birthdays during your space voyage. When you get home at the age of 20, you would find that all your classmates were 65 years old, retired, and enjoying their grandchildren! Because time passed more slowly for you, you will have experienced only five years of life, while your classmates will have experienced a full 50 years. Creepy!!!
So, if your journey began in 2003, it would have taken you only 5 years to travel to the year 2053, whereas it would have taken all of your friends 50 years. In a sense, this means you have been time travelling. This is a way of going to the future at a rate faster than 1 hour per hour.
But achieving speed of light requires an un-imaginable amount of energy but don’t worry Einstein has worried already for us,he theorised that if you were to situate yourself on the edge of a black hole, time would pass more slowly.
Prof Greene explains in his Big Think video: “You hang out [next to a black hole] for a while, you come back, get out of your ship and it will be any number of years into the future, whatever you want all depending on how close you got to the edge of the black hole and how long you hung out there.
“That is time travel to the future.”
Time travel has already happened,wait…what ?
Serial ISS resident Sergei Krikalev holds the record for the longest amount of time spent in space with 803 days, 9 hours, 39 minutes under his belt.
The ISS travels at around 7.66 km/s when orbiting around Earth, and due to the high speed and length of time which he spent in space, the cosmonaut actually arrived back in Earth 0.02 seconds in the future thanks to a process known as time dilation.