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# Visualizing the Planck Length Why is it the Smallest Length in the Universe?

Visualizing the Planck Length Why is it the Smallest Length in the Universe?

The scale of the universe is bigger than you can imagine. It is also smaller than you can imagine. The smallest lenth theorized to be possible, the Planck length is about 4 X 10^-35 meters. Just imagine things that are about the size of your body. Things like the giant earthworm that lives along streams in Australia. Or a big beachball, which can be found near oceans and beaches all across America.

Now, lets go smaller by one order of magnitude, so now we are looking at things that are on the scale of about 10 centimeters. These are things like the shrew, or a chicken egg.

Now let’s go a thousand times smaller than the scale of a human being, on the order of 1 millimeter or one thousand of a meter. Here, you’ll find things like a grain of sand or dust mites.

Let’s go 1000 times smaller than this scale. Now we are going a hundred times smaller than the width of a human hair. And ten times smaller than even bacteria. Here, we are going to find things like large viruses.

Let’s keep going to 1000 times smaller this. This is nanometers, or one billionth of a meter. Now we are exploring a universe that we can’t see with optical telescopes. This is on the scale of the size of molecules like DNA and the glucose molecule, that your body uses as its source of energy. And the scale of the biggest atom – cesium.

Let’s go 1000 times smaller than this. This is one trillionth of a meter. This is on the order of the wavelength of gamma rays. This is the highest energy electromagnetic radiation, consisting of the most energetic photons.

Let’s go 1000 times smaller than this. This is 1X 10^-15 or one quadrillionth of a meter. This is the size of particles that make up the nucleus of all atoms, protons and neutrons. The size of a typical atom is however is 100,000 times bigger than its nucleus.

You would think that we are getting close to the smallest size theorized to exist – the plank length. But we are nowhere close. You have to go a quadrillion times smaller than one quadrillionth of a meter, or 1 X 10^-30 of meter….and you would still need to go another 100,000 times smaller than that, or 1 X 10^-35 meters. Then you would be at the plank length. In fact, if an atom was the size of the earth, a planck length would be smaller than the size of an atom – it would be about the size of a proton.