Question about this "Quantum laser pointer" that I bought

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SUMMARY

The discussion centers on the functionality of a quantum laser pointer purchased from quantumlaserpointer.com. The user, Ben, questions whether the observed refraction pattern at a distance of three feet is indicative of the dual slit experiment, suggesting a misunderstanding of quantum mechanics. A participant clarifies that the observed phenomenon is a classical interference pattern, not a quantum effect, and emphasizes that lasers are coherent-state sources rather than single-photon sources, aligning with classical wave theory as demonstrated by Thomas Young in 1805.

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Benplace
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TL;DR
QuantumLaserPointer.com
I bought one of the lasers from quantumlaserpointer.com
If I remove the cap I can see the two thin slits cut in it.
If I hold the laser around 3ft from a surface it appears to show the refraction pattern.
Is this actually working like the dual slit experiment and the laser photons are going through both slits at the same time?
Thanks,
Ben
 
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No, no quantum effects here. You’re seeing classical light waves interfering with one another, the same purely classical phenomenon that Thomas Young observed around 1805 to show that light is waves of something (waves in the electromagnetic field it turns out, although that took another half-century).
 
I once had a debate at an exhibition during a physics conference with a guy from a school-physics experiment supplier who praised a laser as a "photon source", because I think that's a bit cheating, be cause a laser is not a single-photon source but a "coherent-state" source. If dimmed down to very low intensity it's mostly a "vacuum source", but still not a single-photon source. The result was that the guy gave me a T-shirt for free ;-)).
 

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