Buzz
An event would certainly occur—though it wouldn’t be a major one.
When mass shifts closer to the center of a spinning object, its rotational speed increases. Picture an ice skater drawing her arms inward to spin faster. Similarly, you could theoretically speed up Earth’s rotation by crouching down—though the effect would be incredibly minuscule.
Significant earthquakes can shift mass in a slightly more noticeable—yet still negligible—manner. The 2011 Japan earthquake, for instance, shifted enough mass toward Earth’s core to shorten each day by 0.0000018 seconds. To replicate this effect through jumping, we’d require a population seven million times larger than Earth’s current inhabitants.
What if the entire global population gathered in one location and pushed against the Earth as we leaped upward? If every person on the planet stood side by side, we could all fit within an area the size of Los Angeles—over seven billion people squeezed into 500 square miles. Yet, even if everyone jumped simultaneously in such a confined space, the impact would be minimal. While our combined mass is substantial, it pales in comparison to the Earth’s mass.
Suppose we all jumped 30 centimeters high. The force exerted would push the Earth away from us, but only by an incredibly tiny distance—about 1/100 the width of a hydrogen atom. Just as we would land back in our original spots, the Earth would also return to its initial position in space. There would be no lasting consequences.
On YouTube, VSauce explored this topic in greater depth. Check out his detailed explanation:
