/sci/ - Science & Math

[Anonymous No.7624413]

>all of quantum physics is based off an error

Why does no one acknowledge feynman was incorrect when he said a single slit does not produce an interference pattern? We know it does with monochromatic light.

>pic related. Clear interference pattern. Its just 8x smaller in amplitude than double slit

Here's the video of feynmans error at 28:35: http://www.youtube.com/watch?v=aAgcqgDc-YM

Why is this bad? Bc this started the mystery woowoo nonsense that particles don't follow classical deterministic rules. It encouraged physicists to ignore obvious solutions. The interference pattern is not a result of randomness or wavefunction collapse or conscious particles. Its the result of electromagnetic interactions between the particles and the material around the slits. Tell me why electromagnetic force is ignored suddenly during the double slut experiment? Why isn't feynmans error common knowledge?

[Anonymous No.7624425]

Maybe you should do some basic research into to the topic if it interests you? (protip: random youtube videos with ominous music don't count)

[Anonymous No.7624430]

>>7624413

>Why does no one acknowledge my ignorant blather

[Anonymous No.7624434]

double slit is bullshit

[Anonymous No.7624472]

>>7624413
brb, performing double slut experiment

[Anonymous No.7624496]

>>7624425
>don't question muh textbooks! critical thinking is hard!

[Anonymous No.7624498]

>>7624430
>commenting because my subconcoius knows it true

[Anonymous No.7624500]

>>7624434
Nice b8

[Anonymous No.7624507]

>>7624434
Quantum bullshitters BTFO

[Anonymous No.7624534]

>>7624413
>>>/timecube/

[Anonymous No.7624542]

>>7624434
that's not what you get with a single slit you dumbfuck.
You get a diffraction pattern.
Not seen in a textbook, I did it myself with hair and laser when I was in high school.

[Anonymous No.7624555]

>>7624542
proof it :^)

[Anonymous No.7624566]

>>7624413

Go be a conspiracy theorist somewhere else.
Or just kill yourself

[Anonymous No.7624736]

>>7624496

Before you "question muh textbooks," you have to know what they say. You obviously don't.

[Anonymous No.7624788]

>>7624496
>youtube stoners that think they're experts on a subject because they watched some documentaries and lectures

[Anonymous No.7624822]

>>7624413
So anon, how many feynman lectures did you need to watch before you you knew more about quantum physics than him, and when can we expect a nobel prize from you?

Also, remember to refrain from reading anything about the subject, books will only suppress your genius. Youtube videos are and will always be the purest way to obtain information

[Anonymous No.7625164]

>>7624413
i think the interference you're mentioning is formed by the nonzero thickness of the walls that the slit is on. he doesn't mention it because it is an idealised experiment. the problem is that the double slit result is a totally different phenomenon.
i myself am prefer GR and mathematical physics way more then QM and i think it of course has led to some science gone astray in the past century (but isn't always like that? ;) ),
but you have to give it some amazing results in basic atomic theory.
again though, once you go beyond helium and you have to resort in tedious numerical tricks to get results or shitty hand waving models like the whole molecular chemistry stuff, i don't know wtf is certain. the math just isn't there yet and that may be a good thing.

[Anonymous No.7625781]

Calculus is based on limits and errors . since calculus is used to describe physics then physics must be based on errors too.

[Anonymous No.7625788]

>>7624434
If the single slit has a width that is significantly greater than the wavelength of the light used, then yes, you WILL get a single guassian distribution as shown in your second example. But if the slit is on the order of the wavelength, then you have to take into account all the possible starting positions _within_ the slit, and you get a fucking diffraction pattern.

Thats all also assuming the light is monochromatic. If it is a continuum of wavelengths, you end up overlapping multiple patterns with the narrow slit and the average result is a single band of light, exactly as Feinman was talking about.

[Anonymous No.7625797]

Congratulations for being the first rational person regarding QM I have ever encountered on the internet.

More posts challenging Feynman, please.

[Anonymous No.7625803]

any laser pointer will work, shine it at a knife edge you get a smooth diffraction pattern, shine it at a thin piece of wire you get stripes of interference.

[Anonymous No.7625887]

>>7625788

You are presuming OP or anyone else in the thread cares about reality or real science. /sci/ has become the board twats come to when the non-stop, circle jerk masturbation sessions over in /x/ inflate their ego enough that they decide to blow to cover off "this whole science thing," and then bask in the adoration of all mankind.

Then the first reply to their thread shoots their nonsense ideas to shit, and they spend the rest of the thread being angry and defensive, and calling anyone who agrees with what all evidence points to, "mindless sheep."

>you're saying I have to know something about science in order to have a meaningful discussion about science?? Wat??
--every /x/ twat ever

[Anonymous No.7625896]

>this thread

[Anonymous No.7625905]

>>7625164
>again though, once you go beyond helium and you have to resort in tedious numerical tricks to get results or shitty hand waving models like the whole molecular chemistry stuff
Maybe if you're trying to solve problems by hand. You can pretty accurately predict all kinds of spectra and other molecular properties with enough computation time. The math is there, the computation power isn't; solving approximations of complex systems in a QM model involves a fucking massive number of variables. The simplifications aren't all for making comprehension easier, they're done so the computations don't take 25 years on a desktop computer. And as with most good mathematical approximations, you can always go to higher precision by adding in more terms, which costs more computing time.

[The Only Good Communist is a D(...) No.7625924]

>>7624498

Oh you're one of THOSE "people" on /sci.

>You: 2+2=5
>Me: You're a faggot and a retard
>You: You comment because you know I'm right.

[Anonymous No.7625998]

>>7624413
>Its the result of electromagnetic interactions between the particles and the material around the slits.
If you knew enough about what you're talking about, you could calculate how much of this effect you should observe for a given slit of certain dimensions. Then you can calculate the resulting diffraction pattern. Then you can do the same thing for a double slit. Then you can do an experiment to test your results, and you'll find that the quantum mechanical picture gives more accurate predictions than the model you're proposing. In real systems diffraction around the edges of the slit will always play a part, but it's unlikely that you'll be able to detect this diffraction in a double slit setup because the diffraction from interference is much greater. If you had a really high resolution detector you would observe both diffraction patterns overlaid on each other.

[Anonymous No.7626215]

>>7625924
You seem new to 4chan, and no I'm not the guy you were responding to

[Anonymous No.7626220]

>>7625896
Topkek

[Anonymous No.7626913]

>>7624788
>Implying lectures aren't educational

[Anonymous No.7626980]

>>7624413
>still using transparent backgrounds
>2015
are you fuckin serious

[Anonymous No.7627051]

>>7624413
One way of understanding this which has always had intuitive appeal to me is the so-called Huygens Principle which basically states that every point on a wavefront can be considered a point source for a new spherical wave, and that the evolution of the wavefront can be determined by superposing all of these spherical waves at later times. The Wikipedia article that I linked to has some really nice pictures of this.

Diffraction effects can then be explained using this principle. Imagine, for example, that you shine light through an extremely small slit, say a slit about the size of the wavelength itself, then when plane waves pass through this slit, the part of the wave that goes through the slit acts as a point source and generates a spherical wave, so the light diffracts.

If the slit is larger, however, then the part of the wavefronts that pass through the slit act as multiple little points sources for spherical waves, and these spherical waves interfere with each other to give an interference pattern. In this way, the diffraction pattern is very much like multiple slit interference, except instead of multiple slits, the wave front itself splits into a bunch of adjacent point sources that interfere with each other.

[Anonymous No.7627196]

>>7627051
>every point on a wavefront can be considered a point source for a new spherical wave
yes but why?

[Anonymous No.7627231]

>>7627196
muh Huygens principle

[Anonymous No.7627242]

>>7627231
Obviously. But what I mean is, how does the wavefront 'know' that it's just hit the interface of a slit and thus to begin behaving like a series of point sources?

[Anonymous No.7627266]

>>7627242
It always behaves as point sources. It's just that in the limit of infinite plane waves, all the point sources cancel each other out and you get something exactly equivalent to a plane wave.

It's only when you constrain the wave that things stop canceling.

[Anonymous No.7627283]

>>7627266
Nah think I might agree with Schwartz in saying he got the right answer for the wrong reason.