wave particle duality incorrect?

Has anyone read this week's paper copy of New Scientist? apparently Niels Bohr's theory that nothing exists till it is observed, and of 'complementarity' is not true...

some iranian-american professor has arranged a version of Young's two slit experiment, where he successfully measures the photon as they pass through an individual slit, and it still generates an interference pattern! :eek:

this goes completely against the grain of quantum theory as we currently know it.

what does everyone think of that?

Reply 1

Unregistered

4Ed

what does everyone think of that?

Bollocks.

Reply 2

elpaw

photon? not electron?

Reply 3

4Ed

elpaw

photon? not electron?

the idea of complementarity is present in both photons AND electrons.

except in this example, the guy doing the experiment used photons

Reply 4

Willa

he'll have overlooked something i'm sure!

Can someone scan the feature in. It looks interesting to read but I dont buy new scientist!

Reply 5

elpaw

4Ed

the idea of complementarity is present in both photons AND electrons.

except in this example, the guy doing the experiment used photons

i know that; i just thought it would be much easier to observe electrons. i wonder if the results would be the same if he used electrons....

Reply 6

4Ed

elpaw

i know that; i just thought it would be much easier to observe electrons. i wonder if the results would be the same if he used electrons....

i'm at work atm, but i'll see if i can take a photo of the article on my camera if i have a moment.

the idea was, besides using a photon detector, he's set up a focusing lens, and put little wires in the spots where an interference pattern 'dark spot' would normally be. given that the focused image on the other side is clear, it suggests that there are no photons shining onto the dark spot, as it would distort the image on the other side

Reply 7

RobbieC

Rubbish. He has somehow used the lenses to refract the path and cause the interference, intentionally or not.

Reply 8

username9816

4Ed

some iranian professor

Of course, all the best physicists are iranian. Didn't you know that? :smile:

Reply 9

rts

I read it and the experiment that disproved the complementarity principle seemed quite convincing, showing light behaving as particles and waves in one experiment (enforcing duality principle). But tacked on the end was how this guy can explain it all using wave theory and discard photons. It didn't explain how this worked except that he has a theory involving unquantised EM fields. I would be a lot more convinced if there was a proper explanation of it.

Reply 10

elpaw

discard photons? so how does he explain the photoelectric effect?

Reply 11

rts

"Afshar says the American physicist Willis Lamb and others have explained these particle-like clicks as a result of the interaction of unquantised EM waves and quantised matter particles in the detector"

from earlier on (about Afshar's experiment):

"The second option is to conclude that the particle phenomenon isn't really there, and to use the wave picture for the entire experiment. In this interpretation, the interference pattern and which-way information are not logically inconsistent - the waves do go through both slits, while the "image" each [photon] detector sees corresponds to light waves from only one of the pinholes"