What would happen in this double slit experiment?

TimID
Messages
4
Reaction score
0
Hi,

I was reading Hawking's "The Grand Design" and I came up with a question I didn't know the answer to. He describes a variant of the two slit experiment with particles where a faint light is shone on the slits to determine which one each particle goes through. Naturally this destroys the interference pattern.

What I was wondering is, if the experiment is set up so that this light is still shone on the slits, but the person observing the experiment is unable to see it (whilst still being able to see the final screen) does the interference pattern form?

Regards,

Tim
 
Physics news on Phys.org
It has been experimentally verified that the interference pattern will form even when the source is emitting one photon at a time.
 
Measurement has nothing to do with humans, but with physical interaction. If there was interaction - decoherence - collpase of the wave function, whatever you call it - then the interference pattern is messed up.
 
etamorphmagus: Thanks, that's what I thought, just wasn't sure.
 

Thread 'Why Entangled Photon-Polarization Qubits Violate Bell’s Inequality'

Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In her YouTube video Bell’s Theorem Experiments on Entangled Photons, Dr. Fugate shows how polarization-entangled photons violate Bell’s inequality. In this Insight, I will use quantum information theory to explain why such entangled photon-polarization qubits violate the version of Bell’s inequality due to John Clauser, Michael Horne, Abner Shimony, and Richard Holt known as the...
View full post »

Thread 'Schrödinger equation and classical wave equation'

Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
View full post »

Thread 'How strong is the justification for low probability extreme thermal fluctuations?'

I asked a question related to a table levitating but I am going to try to be specific about my question after one of the forum mentors stated I should make my question more specific (although I'm still not sure why one couldn't have asked if a table levitating is possible according to physics). Specifically, I am interested in knowing how much justification we have for an extreme low probability thermal fluctuation that results in a "miraculous" event compared to, say, a dice roll. Does a...
View full post »

Similar threads

I Double-dark Slit Interference Pattern?
Replies
15
Views
1K
B Yet another double slit thought experiment...
Replies
20
Views
2K
I Does a qubit break interference in the double slit experiment?
Replies
9
Views
161
I Why is there no single slit interference when one slit is closed in a double slit experiment?
2
Replies
55
Views
5K
B Double-slit experiment and time
Replies
24
Views
2K
B Double Double Slit Experiment -- Question about Variations
Replies
3
Views
2K
B Q - Double slit experiment, delayed slit selection observation
Replies
5
Views
2K
I Double Slit Experiment: Measurement versus Observation
Replies
3
Views
1K
B What is causing destructive interference in double slit experiment?
Replies
32
Views
4K
I Double-slit experiment, determining which slit an electron passed thru
Replies
26
Views
3K

Hot Threads

Recent Insights

Back
Top