Movies, books, and other forms of storytelling often play fast and loose with the rules of time. While entertaining, many of these portrayals create myths about how time works—ideas that don’t hold up under scientific scrutiny.

One common myth is that time can be easily traveled backward or forward at will. In films and novels, characters often jump decades or centuries with a machine or magical device. In reality, forward time travel is only possible in tiny increments through high-speed motion or strong gravity, as predicted by relativity. Traveling backward, however, is considered impossible due to causality and the laws of physics.

Another widespread misconception is the notion that the past can be changed without consequences. Stories frequently depict characters preventing events, altering history, or saving ancestors. Physics, however, shows that such changes create paradoxes, like the “grandfather paradox,” which are logically inconsistent and likely forbidden by nature.

Movies also exaggerate the perception of time. Time is sometimes shown as a flexible substance that can be stretched or compressed at will. While subjective perception can vary—moments of boredom feel longer, and exciting events feel shorter—objective time flows consistently according to physical laws, regardless of our experience.

A related myth is the idea of a universal “now.” Many stories treat all time as existing simultaneously, allowing characters to step freely between moments. In reality, relativity shows that simultaneity depends on the observer’s frame of reference. Two people moving at different speeds may disagree on whether events occur at the same time, making a single universal “now” impossible.

Finally, literature and cinema often ignore the role of entropy and the arrow of time. Objects and events in stories may be reversed or loop endlessly, but in the real world, the second law of thermodynamics ensures that disorder increases over time. Broken objects don’t spontaneously repair themselves, and spilled liquids don’t flow back into containers.

While these myths make stories exciting and imaginative, they differ sharply from scientific understanding. Recognizing the difference between fiction and reality helps us appreciate both the creativity of storytelling and the true nature of time in the universe.