To time travel you have to understand the nature of all existence the key component to understand is the space time continuum which is basically the idea that you can’t have space without time and they are one and the same when you effect space you also effect time. If we experience the universe in 3 dimensions length, width and height we also experience the fourth dimension time so currently we can only travel one way at one speed along that dimension. Essentially we are all travelling at rate of 1 minute per minute which is just as boring as it sounds.

Before tackling time travel we must learn some science, let’s start by talking about the theory of relativity imagine you are riding in a car going 50 miles per hour if you were to throw a tennis ball forward it would appear to be going 10 miles per hour forward but will be moving forward at 60 miles per hour to somebody standing on the side of the world let’s call him Tom if you throw the ball backwards it would still appear to be moving at 10 miles per hour to us but well be moving forward going 40 miles per hour to Tom standing on the side on the road. But here’s where it gets confusing back in the 1800’s scientists assumed this applied to everything in the universe even the fastest thing in the universe, light but what they found is that light travels at the same speed about three hundred thousand metres per second no matter how fast the light source or the observer would move it because the speed of light is constant.
Now everyone agrees that speed is determined by dividing the distance travelled by an object by the time the object has to get there that’s why the speed of the ball appears different to each observer you observing 2 different distances for the ball to travel in the same amount of time, but instead of a ball you turn on a torch the light appears to move at the same speed to you and the observer on the side of the road but we know the distance changes so if the speed is constant and the distance changes then time must change with it. Moving through space changes the passage of time making it appear to move slower for the object moving now to boil that down the faster you go the closer you get to the speed of light time begins to slow down if you travel in at speeds to 99% the speed of light one hour for you would be 7 hours for everyone else increase that to 99.99% the speed of light then 1 hour for you becomes 3 days for the rest of the world it means travelling through time is entirely possible and in fact happens every day high speed creates time dilation so astronauts aboard the international space station have experienced this for themselves they hurtle around the earth at 4.76 miles per second granted that’s only a fraction of the speed of light so traveling at that speed for a year the astronauts have only gone 0.01 seconds into the future but still it’s a start all we have to do is figure out how to go faster.
However the bigger problem is that travelling into the future is a one way ticket. That’s where a physicist named Albert Einstein comes according to Einstein there’s no way to get back to the past, so your next step is finding out a way around that special relativity now I know you might say why don’t go faster than light we just don’t know what going faster than light will do will you go backwards in time? Chances are it`s impossible anyway, so we have to find a way around that too. First let me recommend the Alcubierre drive it’s at the forefront of faster than light travel and it attempts to bend the rules instead of breaking them, Miguel Alcubierre released a paper in 1994 explain how the drive works it creates a bubble in space time around the space ship where the universe more or less stays the same, then it constricts space around the bubble and expands space behind the bubble propelling the ship forward because the forces are occurring in space not matter it isn’t tied to the same when the patience is to speed as the ship is moving at a much slower speed inside the bubble where all physical laws are normal so the bubble in theory can move several times  the speed of light however the very workaround to beating the speed of light means that the spaceship wouldn’t experience the time the time dilation one would normally feel as they get closer to the speed of light so many theorists believe that this only solves the problem of travelling through great distances quickly not going back in time for that you need a wormhole or to be more specific call it a Einstein-Rosen bridge as I mentioned before we know that space and time are completely connected and with enough gravitational force space time bend, it’s entirely possible that when enough force present space time could fold over itself just like folding a blanket an Einstein-Rosen bridge is the theoretical path between two spots in space time that have been folded together to touch now here`s where it gets complicated; you would have to move one end of the wormhole to space time to another location close to the speed of light then reverse it back to the original position, if you’ve gone fast enough then time has slowed down for one end of the wormhole so moving through it won’t just mean you will go back to the original location but potentially to the original time as well. However there are some drawbacks to this, you can only into time to the point that the wormhole was created and no further therefore creating one of these today wouldn’t mean we get to go back to see dinosaurs just that future.