# What is the highest frequency of electromagnetic radiation?

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In summary, the maximum frequency of electromagnetic radiation is limited, with the highest observed frequency being 3 * 10^20 Hz for gamma rays. However, this does not necessarily mean it is the highest frequency physically possible. It is speculated that the minimum wavelength for EM radiation may be related to the Planck length, but this is not confirmed as we do not have a confirmed theory of quantum gravity. Therefore, the reason for the limitation of frequency is currently unknown.

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Title says it all.

Also, if the frequency of electromagnetic radiation is limited, why? My guess is the wavelength is limited to the Planck length, and when I plug those numbers into the calculator, I get 1.855 * 10^43 Hz. The maximum (Edit: observed) frequency of a gamma ray is 3 * 10^20 Hz though.

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enter said:
Title says it all.

And here is the short answer: we don't know.

enter said:
My guess is the wavelength is limited to the Planck length

This is a fairly common speculation in quantum gravity, but we don't have a confirmed theory of quantum gravity so we don't know if this speculation is correct.

enter said:
The maximum frequency of a gamma ray is 3 * 10^20 Hz though.

You mean, the highest frequency of a gamma ray that we have observed is 3 * 10^20 Hz. That doesn't mean that's the highest frequency that is physically possible.

vanhees71 and enter
PeterDonis said:
And here is the short answer: we don't know.
This is a fairly common speculation in quantum gravity, but we don't have a confirmed theory of quantum gravity so we don't know if this speculation is correct.
You mean, the highest frequency of a gamma ray that we have observed is 3 * 10^20 Hz. That doesn't mean that's the highest frequency that is physically possible.
Yeah, I misstated the gamma ray part.

I don't understand, how is quantum gravity related to this?

enter said:
how is quantum gravity related to this?

It's related to your guess that the minimum wavelength for EM radiation is related to the Planck length, as I said in post #2.

## 1. What is electromagnetic radiation?

Electromagnetic radiation is a form of energy that is transmitted through space in the form of waves. It includes all types of light, from radio waves to gamma rays.

## 2. What is the highest frequency of electromagnetic radiation?

The highest frequency of electromagnetic radiation is gamma rays, which have a frequency of over 10^19 Hz (hertz). This is also the highest frequency on the electromagnetic spectrum.

## 3. How is frequency related to electromagnetic radiation?

Frequency is one of the properties of electromagnetic radiation and is directly related to the energy and wavelength of the radiation. Higher frequency radiation has more energy and shorter wavelengths, while lower frequency radiation has less energy and longer wavelengths.

## 4. What are some examples of high frequency electromagnetic radiation?

Some examples of high frequency electromagnetic radiation include gamma rays, X-rays, and ultraviolet (UV) rays. These types of radiation have very short wavelengths and high energy levels.

## 5. What are the uses of high frequency electromagnetic radiation?

High frequency electromagnetic radiation has many uses, including medical imaging (such as X-rays and CT scans), sterilization, and cancer treatments. It is also used in telecommunications, such as for satellite communication and wireless technologies.