# The Naked Scientists Forum

### Author Topic: What happens in the double-slit experiment with just one detector?  (Read 1668 times)

#### Toby McCulloch

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##### What happens in the double-slit experiment with just one detector?
« on: 12/01/2011 13:30:03 »
Toby McCulloch  asked the Naked Scientists:

Chris,

I have a query that no books seem to answer!

In the classic electron double slit experiment where;

A = election emitter
B = Slit 1
C= Slit 2
D= electron detector

I understand that an electron can interfere with its self by passing through B and C at the same time

If 100% reliable ( special) detector is placed at slits B and C. The electron can only pass through B or C with no interference.

My question is what happens if a 100% reliable ( special) detector is placed at either slot B or slot C ONLY? (i.e. One slot. Lets say slot B for answer options below)

1.       If detected at B = No interference. If not detected at B must have gone through C = no interference. Basically if one slot has a 100% reliable detector there is no interference and the second detector is superfluous .

OR

2.       If detected at B = No interference. If not detected at B could have gone through C = no interference. OR could still have gone through B and C without detection. Basically if one slot has a 100% reliable detector is there still some interference?

I would be hugely grateful for an answer as I just can not find anything in a text book on this point. If you are unable to answer could you please point me in the right direction.

Toby McCulloch

What do you think?
« Last Edit: 12/01/2011 13:30:03 by _system »

Post by sciconoclast click to view.

#### sciconoclast

• Sr. Member
• Posts: 149
##### What happens in the double-slit experiment with just one detector?
« Reply #1 on: 12/01/2011 17:13:18 »
Shrunk
Excellent Question!

You may be interested in a very similar experiment I performed and posted on this forum: # 303066  " Does Experiment Cotradict Quantum Theory " (Contradict was originally misspelled as shown ).

In this experiment photons where sent through only one of two slits but a double slit pattern appeared on the target screen.   There was a lot of discussion as to if I had actually achieved this.   I have been discussing duplicating this experiment with better equipment with several different labs and it may be confirmed or non-confirmed this year.

The results, if confirmed, will be with a different explanation.   If anyone else wants to duplicate this experiment don't wait on me.  It could only result in carrier advancement or destruction.

#### JP

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##### What happens in the double-slit experiment with just one detector?
« Reply #2 on: 13/01/2011 01:13:08 »
The answer is 1.  If the detector is 100% reliable it can't sneak through without detection.

#### The Naked Scientists Forum

##### What happens in the double-slit experiment with just one detector?
« Reply #2 on: 13/01/2011 01:13:08 »