1.So what is time travel ??
According to the wikipedia Time travel is the concept of movement between certain points in time, analogous to movement between different points in space by an object or a person, typically using a hypothetical device known as a time machine, in the form of a vehicle or of a portal connecting distant points in spacetime, either to an earlier time or to a later time, without the need for the time-traveling body to experience the intervening period in the usual sense.
So The Question Is time Travel Really Possible ??
Special relativity teaches us that the three dimensions of space and the solitary dimension of time are woven together like a fabric. It's impossible to think of them as separate entities, only a singular unified entity — space-time.
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.
Travelling forwards in time is surprisingly easy. Einstein’s special theory of relativity, developed in 1905, shows that time passes at different rates for people who are moving relative to one another - although the effect only becomes large when you get close to the speed of light.Time goes slower for you than for the people you left behind.
If one were to leave Earth in a spacecraft travelling at an appreciable fraction of lightspeed, turn around and come back, only a few years might have passed on board but many years could have gone by on Earth. This is known as the “twins paradox”, since a traveller undertaking such a journey would return to find herself much younger than her twin.
There’s only one problem from anyone wishing to get a glimpse of the future – getting back. It would mean travelling faster than light – and that’s not possible.
But there may be an out to be found in general relativity, Einstein’s theory of gravity that unites space and time as “spacetime”, which curves in the presence of mass. It allows for the possibility of wormholes – a kind of tunnel through spacetime connecting otherwise very distant parts of the universe.
Hmm IF you could build a big enough rocket and if you could reach the center of the Milky Way galaxy — a healthy 20,000 light-years away — in just a couple decades of your personal time.
You could stop for a few hours, have a picnic near Sagittarius A* (the black hole at the center of the galaxy), and then hop back in to your rocket and come back to Earth.
By the time you return you'll be eligible for retirement benefits, if the institution providing those benefits is even around, because while you only traveled for a few decades according to the clock on your ship, about 40,000 years would've passed on the Earth.
In this way some how it is possible to travel near future/distance future. But traveling to past is very defficult.
However it would still be impossible to go back further in time than the point at which the wormhole was created, limiting the options for travel somewhat - and possibly explaining why we haven’t encountered any visitors from the future. If any natural wormholes were formed in the Big Bang, it might be possible to travel to a limited number of points in the past and in the distant universe, but wouldn’t enable one to flit around the cosmos at will as the Doctor seems to do.
Hope you guys like this post and yeah comment your own opinions.