The Electromagnetic Spectrum: Wavelengths, Limits, and the Universe

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Discussion Overview

The discussion revolves around the existence of wavelength limits at both ends of the electromagnetic spectrum, exploring theoretical concepts related to extremely long wavelengths potentially corresponding to the size of the universe, as well as the implications of very short wavelengths and quantum limits.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question whether there are wavelength limits at either end of the electromagnetic spectrum.
  • One participant asserts that there is no limit in either direction.
  • Another participant proposes that the lowest possible theoretical wavelength is zero.
  • It is suggested that shorter wavelength photons require increasingly more energy to produce, which is why particle accelerators must be large to generate particles with short enough wavelengths.
  • One participant claims that the longest wavelength is set by the size of the universe, while the smallest wavelength is determined by the Planck energy, beyond which the concept of "wavelength" may not apply.

Areas of Agreement / Disagreement

Participants express differing views on the existence and nature of wavelength limits, indicating that multiple competing perspectives remain unresolved.

Contextual Notes

There are references to theoretical constructs such as Planck energy and the implications of energy density on the concept of wavelength, which may depend on specific definitions and assumptions that are not fully explored in the discussion.

poeteye
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Are there wavelength limits at either end of the Electromagnetic spectrum? Is it true there could be a wavelength the size of the universe? What happens at the other end? Is there a quantum limit?
 
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No limit in either direction.
 
Pam, the lowest possible theoretical wavelength is zero.
 
poeteye said:
Are there wavelength limits at either end of the Electromagnetic spectrum? Is it true there could be a wavelength the size of the universe? What happens at the other end? Is there a quantum limit?
Shorter wavelength photons are more energetic, so it requires more and more energy to make them. That's sort of the reason particle accelerators get so huge - it takes tremendous amounts of energy to make particles with short enough wavelengths to probe the tiny length scales that are of interest.
 
poeteye said:
Are there wavelength limits at either end of the Electromagnetic spectrum? Is it true there could be a wavelength the size of the universe? What happens at the other end? Is there a quantum limit?

At the upper limit, the longest wavelength (lowest frequency) is set by the size of the universe. At the low end, the smallest wavelength (highest frequency) is set by the Planck energy and corresponds to an energy density at which concepts like "wavelength" break down. I'm sure you can find numbers for each of these easily enough.
 

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