Undergrad Question about this "Quantum laser pointer" that I bought

[Benplace]

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

 

[Nugatory]

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).

 

[vanhees71]

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 ;-)).