Is It Possible To Go To The Past/future

Is it possible to go back and change the past?

short answer no.......nothing or no one can go faster then the speed of light. Enistein 1 sci fi 0

Is it possible to send telepathic messages into the past or future?

Yes this has happen to me so many times, I now know enough when a visions or dream comes to me to get ready and prepare yourself to protect yourself. W hen this happens you are already changing the future when you react and make the change when it comes like in your dream or vision. It comes to past fast, usually for me when I have a vision it happens true within seconds to minutes in the future, but in my dreams it happens the next day to months later....one time I didn't take it seriously it did cost me a ot....after that day I take all my dreams and visions seriously, and I have gotten myself out of a lot of trouble and danger since then.
The past is possible, if you keep it in mind, and then go into a out of body experience, and go astral traveling in the past, you can make the change, but your spirit while in OBE takes excursions on it's own, you you truly cannot control where your spirit takes you. OBE you can travel in the past, present and future.

Time travel to the future is possible but not the the past?

I think most of your basic concepts are right, but your actual numbers are quite a bit off. Your most serious mistake is supposing that you can travel at speeds like "1 light year in a day". That is faster than the speed of light. The SAME theory that explains time dilation (the "slowing down" of the traveler's clock) ALSO says that reaching the speed of light is impossible. You can't have one without the other; both facts follow from the same premises.

So, for example, if a traveler went on a 30-trillion-mile round trip, he would be gone for at least 5 years (earth time), because he can't go faster than 6 trillion miles per year (speed of light). But you're quite right that the amount of time the TRAVELER experiences may be significantly less than 5 years, depending on just how fast he's going.

In order to experience any significant time dilation effect, you have to go VERY, VERY fast--at a significant fraction of the speed of light. Even a speed like 1,000,000 mph will hardly slow your clock down by very much; at that speed, your clock would still run at 99.9998888 percent of the rate of an earth clock. This amounts to 35 seconds of "lost" time PER YEAR. Even if you increase to 100,000,000 mph, one year of "earth time" will still seem like 361 days to you. In order to make 30 years of earth time feel like 5 days, you would have to go at 99.9999896 percent of the speed of light.

BTW, if you want to calculate just how much time slows down for any give traveling speed, here's the formula:

time dilation factor = 1/√(1−(v/c)²)

where "v" is your speed, and "c" is the speed of light. For example, if you go at 90% of the speed of light (v/c = 0.90), the formula shows that the time dilation factor is about 7; which means that your traveler's clock will tick about 7 times slower than an "earth" clock.

How is time travel to the past possible?

It isn't possible really. You would have to go through a black hole which would destroy you but if you did make it it would be the moment the black hole opened and time would be frozen at that moment.

There's another way you would need a wormhole and then you would have to speed your end of the wormhole up to near the speed of light and then go through it to the past.