# Smallest wavelenghth?

• scupydog
In summary, wavelengths can vary greatly, from the smallest possible wavelength of 1.616e-35 metres predicted by quantum mechanics, to the longest possible wavelength which could potentially be associated with zero-point energy. Gamma rays have the shortest wavelengths of any type of electromagnetism, while extremely low frequency has a wavelength of about 100Mm. However, these values can be affected by relativistic doppler shift as objects approach the speed of light.

#### scupydog

Bob S said:
Wavelengths vary over many orders of magnitude; AM radio is about 300 meter wavelength, FM about 3 m, 1 GHz about 30 cm, infrared about 1 to 100 microns, red light about 600 nanometers, blue light about 400 nanometers, etc.
The above quote is from another thread about a month ago, so i started another thread.

As above...red light about 600 nanometers, blue light about 400 nanometers, so what could the smallest possible wavelength of light be or is it infinely small?

or the longest possible wavelength for that matter

Do you mean the smallest wavelength of visible light or any type?

Gamma rays have the shortest wavelengths of any other type of electromagnetism. They can have wavelengths of less than 10 picometre.

On the other hand, Extremely low frequency is abought $$\lambda$$=100Mm

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You might say that the smallest wavelength possible would be http://en.wikipedia.org/wiki/Planck_length" [Broken] (1.616e-35 metres) which is the smallest distance predicted before quantum effects reduce spacetime to a quantum foam.

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Stratosphere said:
Do you mean the smallest wavelength of visible light or any type?

Gamma rays have the shortest wavelengths of any other type of electromagnetism. They can have wavelengths of less than 10 picometre.

On the other hand, Extremely low frequency is abought $$\lambda$$=100Mm

stevebd1 said:
You might say that the smallest wavelength possible would be http://en.wikipedia.org/wiki/Planck_length" [Broken] (1.616e-35 metres) which is the smallest distance predicted before quantum effects reduce spacetime to a quantum foam.

Thx for your replies, but they really don't answer my question...

Could the smallest/longest wavelength be ascosciated with zero point energy?

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Possibly the longest wavelength of light can be associated with a zero-point energy, but the smallest wavelength of light is associated with the highest energy possible in one photon. These are probably limited by Quantum Mechanics, though I'm not sure.

The highest and lowest wavelengths are, naively, as close to infinity and zero as possible, disregarding quantum effects. These can occur as you get red/blue shifted and as you get closer and closer to the speed of light. We can see that from the relativistic doppler shift:
$$\lambda_0=\sqrt{\frac{1+\frac{v}{c}}{1-\frac{v}{c}}}\lambda_s$$
Although since you can never achieve the speed of light the wavelengths will never achieve infinity or zero.