DeBroglie wavelength for particle at rest

[bobaustin]

lambda = h/mv
v -> 0 means lambda is -> infinite?
So if I have an old pickup truck that moves really slow, its matter wave is huge, right?? So it's now a wave and not a particle?

 

[Dick]

I suppose if it's moving REALLY, REALLY slow it might participate in an interference experiment by passing through a double slit and interfering with itself, sure. Isn't that kind of a silly question? Quantum mechanics is for small things.

 

[nlightner]

The DeBroglie wavelength is a fundamental concept in quantum mechanics that describes the wave-like behavior of particles. The equation lambda = h/mv states that the wavelength of a particle is inversely proportional to its velocity. Therefore, as the velocity approaches zero, the wavelength becomes infinitely large.

This does not mean that the particle is no longer a particle, but rather that its wave-like behavior becomes more prominent. In the case of your old pickup truck, its matter wave would indeed be very large due to its slow speed. However, it would still behave like a particle in most situations, as its wavelength would still be much smaller than its size.

The concept of wave-particle duality in quantum mechanics means that all particles, regardless of their speed, have both wave-like and particle-like properties. So while the DeBroglie wavelength may become infinitely large for a particle at rest, it does not change the fact that it is still a particle.