Verified answer

Theoretically you can go to the future but not to the past (to prevent the paradox that you can meet yourself). From this reason this is a one way to the future and you will not be able to go back.

People are already doing this now. The ancients knew of this secret but it's not what you might think. And it does not involve the help of Aliens. You can do it too.

If you mean by some use of technology, then an absolute Yes. You should read Michio Kaku's "Hyperspace." In it, he talkes about how each stage in a civilization's development is characterized by the amount of energy a society can harness. We will enter a type I civilization in 150 yrs, and be producing 10^16 petawatts of power. At that point, controlling the weather should be a real possibility.1000 yrs. after that, our world will develop into a type II civilization in which we finally be able to leave and colonize other solar systems. (10^36 petawatts of power) Sometime between this stage and stage III time travel could be mastered. Traveling into and changing the past is also possible mind you. There is a loop hole around Heisenberg's uncertainty principle, in which information is flowing from the future into the past and vice versa. ie. Some scientists (Feyman and Wheler) theorize that an electron is moving into the future while it's counterpart, or positron, is moving into the past. (antimatter). Becuase both are connected by quantum waves, they can be "tweaked" so to speak according to the eternal moment of NOW.

Lastly, once a civilization passes into stage III (5000-7000 yrs into the future), they should be be able to escape the 3rd dimension of this universe (while producing 10^46 petawatts). At some point, the final step is to be able to create more energy than the entire universe is made up of now. Such a civilization would become a type IV and could theoretically be able to produce entire new universes.

I doubt if we could in a physical sense, however because of the possibility of a space/time continuum, and given that the past has shaped our present and our present shapes our future and given that quantum mechanics flies in the face of macro-physics as we know it, perhaps meta-physics or a pure spiritual dimension exists among the 16 or so that quantum mechanics suggests. If all we are in reality is energy, and the law of conservation of energy is true, once that energy is "expended" it must still exhist but in an altered form. And because that energy is conserved, it serves as a link to not only the past but to the future because it will exhist in the future. Unfortunately, we probably will have to die before our energy goes to the next level or dimension.

It is theoretically possible to travel back in time. But given the mass and speed necessary to achieve this it may be technologically impossible to achieve.

I believe its possible but not with current understanding of physics or with technology

Quite impossible, but who knows?

Because of paradoxical thinking, time travel might not be possible

The great physicists all say no, who am I to argue?