Poisson/Arago's spot in water?

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Poisson's spot, a phenomenon related to the wave nature of light, raises questions about its equivalent in water waves, particularly surface gravity waves. The discussion highlights the differences between electromagnetic waves and water waves, such as dispersion relations and viscosity effects. While Lamb's work on sound waves does not indicate a similar effect, the concept of observing an Arago-like spot in water waves remains intriguing. The idea of conducting an undergraduate project to explore this 2D equivalent, akin to an inverted single slit experiment, is proposed. This exploration could yield interesting insights into wave behavior in different mediums.
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Hello,

So Poisson's spot is a (peculiar) effect of light due to its wave nature (it's the bright point one would see in the middle of the shadow of a perfectly round coin).

So I was wondering, has Arago's spot been observed for water waves too? For example in a 2D equivalent, i.e. for surface gravity waves.
 
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Interesting... it seems that there could be, but water waves are slightly different than electromagnetic waves- the dispersion relation for example, and dissipation due to viscosity. Lamb only treats sound waves diffracted though a aperture that is smaller than the wavelength, and those results do not indicate any phenomenon similar to the spot of Arago.

Seems like a good undergraduate project, actually!
 
The 2D equivalent would be like an inverted single slit experiment - should be observable.
 

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