How might a time machine work?

As I remember of classes 40 years ago...

As we understand time, it is impossible to actually go back in time.

It may be possible to view a past time by traveling faster than the speed of light, but it would also require the image transmittal to be faster than light.

To go forward in time, the passing of time slows as an object moves faster.

A rocket sent to the moon and back with a precise clock on it and other clock with the same initial precise time on it, will disagree by a small amount of time, whether in milliseconds or a full second.

A person sent out at a very high speed to travel in space will experience time passing at a slower rate than back on Earth. In theory traveling fast enough, a person can travel for 10 years and return to a future 20 years after he left. the problem is, those 20 years (or 10 year difference) have actually occurred and can't go back.

Theoretically, a person can travel to the future if approaching the speed of light.

That person would experience their time, and the Earth would be older.

I think using some full body and brain manipulation device we could experience what it would be like.

If someone stuck you in pod with a bunch of transmitters stuck on you head and you went back to 1940 I think it would be enough to simulate time travel.

The computer would monitor your vital signs and if you get a shock it would treat you and wake you up.

It gets to the point where it is more refined and humans actually have an interface on their body.  So you plug in electronic devices right into the body or brain.

Just imagine a diet tool or study aid that plugs into our arm.

It wouldn't work. That is science fiction.

It would move you from time to time

It would need to bend gravity. Even then, you would only be able to speed or slow down time.