Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Bill S on 25/10/2015 01:39:02

Title: Do photons and massive particles behave the same in double slit experiments?
Post by: Bill S on 25/10/2015 01:39:02

Photons passing individually through double slits produce an interference pattern. If  behind the slits there are detectors that can determine which slit a photon passed through, the interference pattern vanishes.  This occurs, even if the decision to turn on the detectors is not made until after the photon has passed through the slit.

Is this result the same with electrons, and other massive particles?

Title: Re: Do photons and massive particles behave the same in double slit experiments?
Post by: evan_au on 25/10/2015 03:22:50

Quantum effects have been demonstrated for particles as large as buckeyballs (http://en.wikipedia.org/wiki/Wave%E2%80%93particle_duality#Wave_behavior_of_large_objects) (C₆₀).

There is a claim that the dual-slit effect has been demonstrated on molecules having over 800 atoms (http://en.wikipedia.org/wiki/Double-slit_experiment#Interference_of_individual_particles).

Title: Re: Do photons and massive particles behave the same in double slit experiments?
Post by: PmbPhy on 25/10/2015 07:21:39

Quote from: Bill S on 25/10/2015 01:39:02

Photons passing individually through double slits produce an interference pattern. If  behind the slits there are detectors that can determine which slit a photon passed through, the interference pattern vanishes.  This occurs, even if the decision to turn on the detectors is not made until after the photon has passed through the slit.

Is this result the same with electrons, and other massive particles?

Particles such as the electron have wavelengths which are too small for the kind of widths used with photons. But the same behavior is found when the electrons are passed through crystals. The crystal lattice behaves like a double slit screen in some aspects.

Title: Re: Do photons and massive particles behave the same in double slit experiments?
Post by: Bill S on 25/10/2015 17:46:26

Thanks folks.  I thought that was the case, but wanted to be sure before using it in a discussion with someone who thinks the delayed decision double slit experiment can be used to argue for photons not "experiencing" time.

Title: Re: Do photons and massive particles behave the same in double slit experiments?
Post by: chris on 25/10/2015 22:06:55

Quote from: evan_au on 25/10/2015 03:22:50

There is a claim that the dual-slit effect has been demonstrated on molecules having over 800 atoms.

Impressive!