Planck length - what is it really?

In summary, the Planck length is a unit of length that is derived from three fundamental physical constants and is approximately 1.6 x 10^-35 meters. It is important because it is believed to be the smallest possible length in the laws of physics and is the scale at which quantum gravity effects become significant. The Planck length was first proposed by Max Planck in 1899 and later confirmed by modern theories of quantum gravity. It cannot be measured due to its extremely small size and is considered the most fundamental of the Planck units.
  • #1
Dialga
1
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Hello everyone.

After reading most of the existing topics on the Planck length, I still haven't found what the Planck length really is. Some references say nothing can possibly be smaller than the Planck length, whereas others say it's just a threshold below which "special" things happen.

So... can things be smaller than the Planck length, or not? Most importantly, can a singularity be smaller than the Planck length?

Thanks in advance.
 
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1. What is the Planck length?

The Planck length is a unit of length that is derived from three fundamental physical constants: the speed of light, the gravitational constant, and the reduced Planck constant. It is approximately 1.6 x 10^-35 meters.

2. Why is the Planck length important?

The Planck length is important because it is believed to be the smallest possible length that has any meaning within the laws of physics. It is also the scale at which quantum gravity effects become significant.

3. How was the Planck length discovered?

The Planck length was first proposed by German physicist Max Planck in 1899 as a unit of length that could be derived from the fundamental constants. It was later confirmed by modern theories of quantum gravity.

4. Can the Planck length be measured?

No, the Planck length is so small that it is beyond the capabilities of our current technology to measure. It is also believed that at this scale, the laws of physics as we know them break down.

5. What is the relationship between the Planck length and other Planck units?

The Planck length is one of several Planck units, which are derived from the same fundamental constants. These include the Planck time, Planck mass, and Planck energy. The Planck length is considered the most fundamental of these units, as it is the scale at which all others are derived.

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