Gravity is the weakest of the fundamental forces of nature, yet if you have enough of it, it can create the most powerful thing in the known universe, a black hole.

The very idea of a black hole didn't really exist until the early 20th century, and now they are regularly

found by the world's most powerful telescopes.

As much as we know about them, there is even more we don't know and probably will never know.

Learn more about black holes, what they are, and how they work on this episode of Everything

Everywhere Daily. When I say that gravity is the weakest of the fundamental forces in nature, it might come as a surprise to you.

After all, gravity is what causes us to fall down, and it's why the planets revolve around the sun.

However, consider this.

If you pick up an object, you can counter the entire gravitational force of the planet Earth with just your arm.

Technically, there is a gravitational attraction between any two objects.

However, for the most part, it's extremely weak.

The gravitational attraction between two people, for example, is so weak that it can barely be measured.

Gravity is a fundamental property of mass, and the thing is, you can just keep piling up mass to get more and more gravity.

The gravity we experience on Earth is defined as 1G or 1 gravitational equivalent.

Let's say you landed on a planet with twice the gravity. or one gravitational equivalent.

Let's say you landed on a planet with twice the gravitational force of Earth or 2G's.

You would definitely notice that something was different.

If you weighed 150 pounds or 68 kilograms on earth, it would be like walking

around with that weight on your shoulders all the time. Movement would be difficult and even simple

falls would potentially break bones. At 3G even simple movement would be difficult

for all but elite athletes. The Icelandic strongman, Haf Thor Bjornson, once set a world's record by taking five steps with a 1,430

pound log on his shoulders. That would be the equivalent of walking in a 4.6 g environment. At 5 g's it would be difficult for any human to

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