# Would dbb cause an unequalness between the paths?

1. Jul 19, 2013

### San K

The de broglie bohm theory posits that the photon goes through one of the slits and the waves through both. (In a single particle double slit experiment)

The waves are probability waves, however they must be modelling an underlying resource.

Thus would they create some sort of unequalness between the "waves" ? That are transervsing the paths that emerge from the two slits.

2. Aug 14, 2013

### sugeet

Where are the 'waves' here?, what do you mean by 'waves', when you are talking about a single photon, where is the question of 'waves'? Correct me If I got you wrong.
Here we are discussing a single photon interference !!!
A photon interferes with itself!!!,

3. Aug 14, 2013

### San K

Sugeet, thanks for replying. I grant you that --- instead of a wave its a wave function. Nevertheless take a look at below (from wikipedia):

In de Broglie–Bohm theory, the wavefunction travels through both slits, but each particle has a well-defined trajectory that passes through exactly one of the slits. The final position of the particle on the detector screen and the slit through which the particle passes is determined by the initial position of the particle. Such initial position is not knowable or controllable by the experimenter, so there is an appearance of randomness in the pattern of detection. The wave function interferes with itself and guides the particles in such a way that the particles avoid the regions in which the interference is destructive and are attracted to the regions in which the interference is constructive, resulting in the interference pattern on the detector screen.

In my opinion- the wave-function is a mathematical constructed to model something that we don't understand yet. But there is "something" - and perhaphs that "something" passes through both slits

4. Aug 15, 2013

### sugeet

So I get what you are telling, and its very interesting, still I did not understand the un-equalness you are talking about!

5. Aug 15, 2013

### San K

the photon, per DBB hypothesis/interpretation, is going through one slit.....thus aren't the paths are unbalanced?......

one path has wave-function but no photon
other path has wave-function plus photon

Would not the interference pattern be different from the one that emerges from a hypothesis/interpretation that says - the photon goes through both slits at the same time? And the interferes with itself

Last edited: Aug 15, 2013
6. Aug 16, 2013

### Demystifier

True.

I think your problem is that you are not certain what exactly do you mean by the word "photon". In the first quote above the "photon" means a pointlike particle, while in the second it means something else. You cannot have a consistent logical reasoning if you use the same word with two different meanings. So pick one definition for the word "photon" and try to reformulate your question again.

7. Aug 16, 2013

### San K

Let's go with - Photon as excitation of the EM field.

Wouldn't the patterns be different:

When the excitation travels through one slit (DBB interpretation) Vs both slits (some other interpretation)?

Am I missing something?

Last edited: Aug 16, 2013
8. Aug 16, 2013

### StevieTNZ

By wave, you mean probability wave. My guess would be no unequalness, as in the double-slit you would still get the same results as Quantum Mechanics, with Bohmian Mechanics.

9. Aug 17, 2013

### San K

Ok thanks all. Let's, informally, close this thread. There are more interesting topics to focus on.

10. Aug 19, 2013

### Demystifier

The excitation travels through both slits, even in the dBB interpretation.

11. Aug 21, 2013

### San K

Interesting. Thanks Demystifier.

Does DBB say if "something" travels, randomly, through just one of the slits? What would that be?......in case of a single photon, at a time, of course....

12. Aug 21, 2013

### Demystifier

That would be a "particle", where "particle" means point-like object strictly localized in space. In the case of photon, this is NOT an excitation of the field.

13. Aug 21, 2013

### San K

Got it. Thanks Demystifier......for demystifing this......:)

14. Aug 22, 2013

### Demystifier

That's what I do for living.

E.g., see my rather long paper:
http://arxiv.org/abs/quant-ph/0609163 [Found.Phys.37:1563-1611,2007]

And even right now, I am writing another very long paper in which I plan to completely demystify relativistic Bohmian mechanics.

15. Aug 24, 2013

### San K

Browsed through the paper. Looks great. Will get back...:)