10 rules of time travel

10 rules of time travel

There are 10 rules of time travel. Whatever natural principles the creator of imaginary worlds chooses to follow, they must not permit true paradoxes.

Traveling into the future is easy

Traveling into the future is easy

We constantly advance one second into the future at a constant rate.

Traveling into the past is hard — but maybe not impossible

Traveling into the past is hard — but maybe not impossible

Traveling backward in time would not be feasible if Isaac Newton’s theory of absolute space and time had been an accurate representation of nature.

Traveling through time is like traveling through space

Traveling through time is like traveling through space

Similar to traveling through space, traveling through time involves moving along a predetermined path that the universe has presumably set up to help you arrive at a previous point in time.

Things that travel together, age together

Things that travel together, age together

Clocks and other objects will all experience time exactly the same as you do if you travel through time and bring them with you.

Black holes are not time machines

Black holes are not time machines

Sadly, a black hole wouldn’t spit you out at a later period if you fell into one. It wouldn’t even spit you out; instead, it would eat you whole and gain a little bit of weight in the process.

If something happened, it happened

If something happened, it happened

People seek to travel back in time and alter the past via time travel devices. The past is already past and cannot be changed.

There is no meta-time

There is no meta-time

The least realistic time-travel movie of all time might be Back to the Future. When Marty McFly changes the past violating Rule 6, the future “instantaneously” changes.

You can’t travel back to before the time machine was built

You can’t travel back to before the time machine was built

If you build a time machine where none previously existed, future travelers may be able to return to that period, but nothing can assist you in return to moments before the machine was established.

Unless you go to a parallel universe

Unless you go to a parallel universe

Parallel universes, such as those considered in the many-worlds interpretation of quantum mechanics could create potential loopholes for some of the above laws.

And even then, your old universe is still there

And even then, your old universe is still there

If you have reliable records of making some poor decisions about your social life in high school, those decisions were made and cannot be reversed.