Trivial question about units (Hans Bethe Small Hole Diffraction)

In summary, the conversation discusses Hans Bethe's paper and the possible differences between two sets of dipoles. It is suggested that the difference may be due to the use of CGS vs SI units, specifically in regards to the value of ##4\pi\epsilon_0##. A link is provided for further explanation and conversions.
  • #1
PhDeezNutz
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Homework Statement
Just a question about units/convention. In Hans Bethe's paper he says the equivalent electric and magnetic dipoles of a small circular aperture are

##\vec{p} = \frac{1}{3 \pi} a^3 \vec{E}_0##
##\vec{m} = \frac{2}{3 \pi} a^3 \vec{H}_0##

Alternatively Jackson (Section 9.5 Third Edition) (where he references Hans Bethe's paper) contends the equivalent aperture dipoles are

##\vec{p} = \frac{4 \epsilon_0 a^3}{3} \vec{E}_0##
##\vec{m} = \frac{8 a^3}{3} \vec{H}_0##
Relevant Equations
See above
http://www.physics.miami.edu/~curtright/Diffraction/Bethe1944.pdf Hans Bethe's paper

Jackson doesn't take any issue with Hans Bethe's paper as far as I can tell when he references it. That leads me to believe the two sets of dipoles are equivalent and there happens to be an "old school" convention that I am not familiar with. Can anyone inform me?

Thanks in advanced.
 
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  • #2
I think it is CGS vs SI and the difference is basicly ##4\pi\epsilon_0##. You can work out the details it always gets me a headache.
 
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1. What is Hans Bethe Small Hole Diffraction?

Hans Bethe Small Hole Diffraction is a phenomenon in which light passing through a small aperture or hole exhibits diffraction patterns. This was first studied by physicist Hans Bethe in the early 20th century.

2. How does the size of the hole affect the diffraction pattern?

The size of the hole plays a crucial role in the diffraction pattern. A smaller hole will produce a wider diffraction pattern, while a larger hole will produce a narrower pattern. This is due to the wavelength of light and the principle of diffraction.

3. What is the difference between small hole diffraction and single-slit diffraction?

Small hole diffraction and single-slit diffraction are both phenomena that involve light passing through a narrow opening. The main difference is that small hole diffraction occurs when light passes through a small circular aperture, while single-slit diffraction occurs when light passes through a single narrow slit.

4. How does the distance between the hole and the screen affect the diffraction pattern?

The distance between the hole and the screen, also known as the distance of observation, affects the diffraction pattern by changing the size of the pattern on the screen. As the distance increases, the size of the pattern decreases. This is due to the spreading out of the diffracted waves as they travel further from the hole.

5. What are some practical applications of small hole diffraction?

Small hole diffraction has many practical applications, including in fields such as astronomy, microscopy, and photography. It is also used in the design of optical instruments, such as telescopes and cameras, to improve image quality by reducing diffraction effects.

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