last time human believe we can fly? travel to moon? talk to another person in another part of the earth? No right. But it all is being acheived now.
do you believe in we can build a building using printer? Now we have 3D printer.

the law of physics is defined by human and human tend to make a lot of assumption and mistakes.
And whats more there is no 100% claim that it is impossible to invent a time machine and have instant transfer right?

VR consider breakthrough? I dun see how it benefits human daily life as compared to the item i mentioned above (althought it may posed massive security issue as well).
Oh ya talking about medical. Until now still no cure for AIDS and HIV. Now summore Zika inkambing. Its more beneficial than those bla bla bla medical advanced.

Stephen hawking once say things cannot make itself impossible. If one can travel to the past, they can alter the history and does makes the thing happening now will not be happen. So he concluded that traveling to the past is impossible.

I agree with him in certain way but dont forget that they are a lot of scientist making debut on this particular subject.

What i rather believe is the following debut:
Time travel to the past, if at all possible, may only go back as far as the first time machine. Since the past of our civilization lacks a time machine, it is immutable, whereas the past of more advanced civilizations may be mutable.