Not true. An experiment was done and the result was proof that travel into the future is possible. It involved two clocks and a jet aircraft. I think we are all familiar with it.
Now...travel into the past? That is quite a bit more problematic.
I travel through time, all the time.
October 1, 2020, 10:44, soon to be 10:45, and continuing...
Nano second by nano second.
Why would I want to travel into the past? To watch love ones die again? To watch loved one suffer from disease? To experience the love that recall to this day—as clearly as I felt it then? But miss the person with who I shared it?
No thanks. My mind tortures me with that every night.
My future is relatively short. And while I am in fine shape today...the good days coming are outweighed by the bad days that are inevitable.
The ultimate good days will last forever—so there is time to wait for them.
That experiment proved that two clocks are not exactly the same. Time does not “slow down”, and it is not a dimension.