Am I retarded or is everyone else retarded? How is this any

>>8060621
As in, the tool you're using to observe the phenomenon will slightly alter the phenomenon?

>>8060621
I suppose it would be different in the sense that the observing mechanism is not changing the frequency or measureable input or output, but the actual perceived state of matter or energy in question.

>>8060621
But measurement doesn't merely slightly disturb a quantum system, it completely changes it.

>>8060621
It's the same sort of thing, just that the changes made to a Quantum system are much more noticeable.

>>8060621
Because a voltmeter changing the current in a circuit is typically very small compared to the current going on in the circuit. As you get an arbitrarily "ideal" voltmeter, the current change can become negligibly small. Measuring which slit the electron goes through doesn't just change the interference pattern a little bit, it makes a completely different shape. Further, if you don't make any measurement, even the question "which slit did the electron go through?" doesn't make any sense. I can't think of an analogous idea in the case of the voltmeter.

>>8060674
>if you don't make any measurement, even the question "which slit did the electron go through?" doesn't make any sense.
debatable

>>8060625
>>8060640
>>8060668
>>8060673
>>8060674
I guess my question is "why do normies think that the DSE is an indicator of some kind of quantum magic that can't be explained by science because reasons?"

>>8060683
Because it is actually p weird but often explained in a misleading way, usually from the use of the word "observe".

>>8060683
You got me there. Seems like every time mankind runs into a new question the lowest common start screaming that it can't be answered. :/

More a psychology question really?

>>8060687
I would second this

>>8060683
Because the kinds of people who feel the need to tell the public about quantum mechanics are more often motivated by financial or other personal gain than actually informing

>>8060621
Actual relevant question. Does the velocity of a fired electron have any bearing on the pattern which appears in a double slit experiment?

>>8060704
The wavelength is related to momentum so yeah

>>8060708
Does the pattern get narrower or wider with more velocity?

>>8060718
Narrower

>>8060723
Are you sure?

>>8060728
Higher velocity > higher momentum > smaller wavelength > smaller angle needed to get to the next interference point

>>8060733
Interesting. So if higher velocity/momentum results in (I presume) less deflection could it be that the slit's electrons are merely deflecting the passing particles?

>>8060738
I'm having a hard time gauging what you're trying to ask.

Are you trying to suggest that the waveform is somehow a 'deflection'?

A deflection of any sort would simply lead to an altered destination for the particle in question, or in the case of a wave, a vaguely altered interference pattern.

I don't see the relevance.

>>8060738
It's not really deflection though, the electron still behaves as a wave

>>8060754
Basically I'm asking if what happens (or could be happening) is this:
electron is flying straight toward the slit
electron interacts with the slit's electrons and protons and thus its momentum is changed
since it's momentum is changed by the interactions, it (probably) no longer travels straight but is deflected off at a random angle, but weighted toward certain spots more than others because the particles which make up the slit can only have certain energy levels, thus producing the characteristic interference pattern

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>still using double slit as the example of electron wave properties

Guys, it's 2016 and we've been looking at atoms and electron wavefunctions for 30 years now.

>>8060775
Thing is, you can't really explain the tendency to form a pattern without wave like behaviour

>>8060704
>could
>>8060708
>>8060718
>>8060723
>>8060733
>>8060738

This is not right, for many reasons. First, momentum in one axis has no necessary effect on another axis. If the propagation direction is z and the direction across the interference fringes is x, then p_z's distribution only affects z. Shooting the electrons faster in z, or with more or less uncertainty in z or in p_z, has no effect on x or p_x.

Second, the relationship is between delta-x and delta-p_x, not between delta-x and <p_x>. So a particle with large <p_x> can have large delta-p_x, allowing for small delta-x, but it can also have a small delta-p_x, requiring a large delta-x. In other words, there's a difference between mean and standard deviation.

Third, the uncertainty principle does not *require* that delta-x * delta-p_x = hbar/2. The expression is an inequality ( >= ); a large delta-x does not require a small delta-p_x, both can be large. The only thing the uncertainty principle requires is that delta-x and delta-p_x cannot both be arbitrarily small.

>>8060775
I'm sorry OP, I give up.

I feel like I'm tossing straight ahead and you're swinging at a curve ball.

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>>8060793
>If the propagation direction is z and the direction across the interference fringes is x, then p_z's distribution only affects z. Shooting the electrons faster in z, or with more or less uncertainty in z or in p_z, has no effect on x or p_x.
It does change the net direction of momentum though?

>>8060775
But it doesn't deflect randomly at all. It forms an interference pattern.

Can you explain why there are dark fringes in the pattern if the deflection is random?

>>8060785
>Thing is, you can't really explain the tendency to form a pattern without wave like behaviour
Well if the slit can only contribute certain quantized amounts of momentum to the passing particle a pattern is the natural consequence.

>>8060805
See above. By random I merely meant that each individual particle ends up at an unpredictable location.

>>8060804
>It does change the net direction of momentum though?

Sure, although again we're talking about <p>, the expected value, which corresponds to the classical momentum. Basically, the operators x and p_x do not commute, but x commutes with z and p_z. So changes in p_z affect overall p, but that has no effect on the interference fringes, because they're a phenomenon involving x and p_x.

>>8060810
And how is that related to the separation of the slits?

>>8060810
>Well if the slit can only contribute certain quantized amounts of momentum to the passing particle a pattern is the natural consequence.

But then the single-slit experiment fails. Remember, when just one slit is open (either one), you get a big, continuous smeared gaussian across the whole interference area. So obviously the slit can impart the apparently "forbidden" momenta.

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>>8060621
brb conducting double slut experiment

>>8060852
please let us know of the results. ;)

>>8060828
>And how is that related to the separation of the slits?
Varying the separation of the slits alters the travel time of the pressure wave induced in the material between the slits, and thus the momentum that will be delivered back to the passing electron when it returns.

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>>8060833
>Remember, when just one slit is open (either one), you get a big, continuous smeared gaussian across the whole interference area
I thought single slit went like this?

OP, why don't you just read about the double slit experiment on Wikipedia first?

There is no point talking about interpretations if you have the basic facts about it wrong.

Literally all that meme experiment was is this:
>one slit open, oh fug a bell curve!
>have slit open on other side, it shifted!!!!
>what happens if we open both xDDDD??!
>oh fug the disitribution is like the slits with wave intensities :DD

>>8060621
The experiment highlights an important peculiarity of quantum mechanics.

In Classical physics, a measurement tells you what state the system was in just before it was measured.

In Quantum Mechanics, a measurement tells you what state the system is in just after measurement (assuming no degeneracy in the measured eigenvalue).

>>8060919
Wouldn't that make it dependent on the speed of the pressure wave though? So it should depend on temperature and the material?

>>8060943
I suppose it should, though an easier rebuttal would be that it should also then depend on the amount of material on the 'outside' of the slits.

>>8060625
It's obvious that electrons emit some kind of field, comprised of either finer particles, or waves in the ether. Google the spherical standing wave theory.

(AETHER FTW)

>>8060775
Interesting.

Test: make the slits out of different atoms and see if the pattern changes.

>>8061125
As far as I'm aware it doesn't.

Though on another level all slits would have the same boundary material; electrons and protons.

ITT: Autism, this is why we all stick with classic mechanics.

>>8060812
hello sorry but could an increase in momentum not be taken as a shorted wavelength? thanks

>>8062558
shorter*
thereby having an effect on diffracting, resulting in a narrower/broader pattern depending on z

>>8062562
diffraction*
thanks

>>8062558
>>8062562
The wavelength is shorter in z, but that does not mean that the wavelength in x must be shorter. Each dimension has its own, independent uncertainty equation. Also, just because the z wavelength is short does not imply that there must be great position uncertainty in z. The electron could have a high, but very uncertain z-momentum along with a very certain z-position, for example.