Visualization of Einstein’s Special Relativity

When one thinks about events happening with reference frames moving near the speed of light, he or she can come up with some wierd paradoxes. A paradox is an event which causes a logical impossibility in another frame. Paradoxes in relativity can get complicated, but Einstein’s theory of special relativity gives logical explanations of them.

For example, image a loaf of bread one foot long laying on a conveyer belt moving near the speed of light. Now imagine a butcher with two knives standing alongside the conveyer belt. In his frame of reference, he chops both of his knives one foot apart at the same instant. What happens as the loaf passes by? Well, according to classical physics (not relativity), if he chops down right as the loaf is in between his knives, he wont cut the bread (he will be very close!).

But what if we include relativity? The butcher will see the loaf traveling very fast, and thus he will see it as having a shorter length than when it’s at rest. So when he chops down he will have more clearance, and definitely shouldn’t cut the bread. Simple enough? Try switching reference frames. Now the bread sees the butcher approaching fast. Since moving objects shrink, his knives are less than one foot apart! Wont he cut the bread? Think about it while watching this visualization.

Thanks for the video to the Rocker Spaniels!

This is a complicated topic, so the explanations are complicated as well, but bear with it!

Do you think he will cut the bread? Wouldn’t this cause a logical impossibility if so? In the butcher’s frame he wont cut the bread, but in the bread’s frame he will? There’s one thing we didn’t account for. The butcher thinks he’s chopping simultaneously, BUT as Einstein told us, events in two different reference frames are NOT seen as simultaneous if one is moving. The bread will see the butchers knives chopping at different times! Different enough to not be sliced in either reference frame!