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captainjaneway@lemmy.world ⁨8⁩ ⁨months⁩ ago

The word “observed” has largely been conflated with human perception in the layperson’s understanding of quantum mechanics. When they were first experimenting with the dual slit experiment, they were simply trying to make measurements to predict where an electron might end up after entering one of the two slits. However they soon discovered that their measurements changed the behavior of the electron. That behavior has been denoted as an observation however observation is very vague.

It’s better to say “a measurement which causes a wave-function collapse” rather than an observation. When phrased that way, it feels a lot more explicit and it allows lay people like myself to ask the next question “what causes a wave function to collapse?”

Source: I just asked my physics PhD wife about this a couple nights ago and she did her best to explain it to me.

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Korne127@lemmy.world ⁨8⁩ ⁨months⁩ ago
I’m sorry but what you describe pretty much sounds like… observed

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- MoonJellyfish@lemmy.today ⁨8⁩ ⁨months⁩ ago
  To observe it you have to interact with it in some way. This mean in order to “see” it you need to shoot some photons at it or send some radio signals which will reflect. It all has an influence.
  
  So the problem is not “observing” in in some philosophical sense. The problem is that you need to interact with it in order to “observe” it.
  
  It’s the interaction that makes “wave function to collapse” not the fact that you observed it.
  
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- captainjaneway@lemmy.world ⁨8⁩ ⁨months⁩ ago
  If you use your eyes, nothing happens. Most people think “observe” means they can just look at the experiment and expect it to change. That’s why so many people end up in metaphysics thinking their own perception has any impact on the outcomes of physical states. In reality, it makes no difference.
  
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piecat@lemmy.world ⁨7⁩ ⁨months⁩ ago
Say you were a spy, and you think there’s a laser guarding the largest diamond in the world.

There’s no way to detect if the laser is there without putting some form of matter in the way of the laser. Be it a hand, or spray bottle.

Now at the museum, a mist won’t set off the alarm, but you’re still reflecting some of the photons out of the beam and into your eyes. Otherwise you wouldn’t see the beam…

But for a quantum experiment, where we care about each individual photon, spraying a fine mist will affect the experiment. Sticking anything in that laser beam path will affect the measurement.

So how do you make a measurement without interacting?

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- Churbleyimyam@lemm.ee ⁨7⁩ ⁨months⁩ ago
  That makes perfect sense
  
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AngryCommieKender@lemmy.world ⁨7⁩ ⁨months⁩ ago
“The wave function collapse is just this thing that happens, you know.”

-Gag Halfrunt

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DogWater@lemmy.world ⁨8⁩ ⁨months⁩ ago
For a mathless explanation, I believe it’s because in the quantum world all the atoms that interact are part of the same system. That includes the ones that make up the instruments and the scientists themselves. If you put the photons in an experimental apparatus the results can change because the system is different. Meaning you can influence the waveform collapse simply by experimenting to try and understand it.

I hope that’s right I watch a ton of physics YouTube, so I hope I’m absorbing some of this stuff.

For more crazy shit, see how photons traveling across the universe cause the electron they originate from at the start and the electron they terminate at the end to agree to exchange that energy across space and time. It’s mind bending. From the photon perspective (at the speed of light) a journey across the cosmos is instantaneous. No time passes for the photon from its frame of reference.

On YouTube; PBS Spacetime, History of the universe, Alpha Phoenix, veritasium, cool worlds, astrum, vsauce

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- Corkyskog@sh.itjust.works ⁨7⁩ ⁨months⁩ ago
  Wait, what’s the math? At this point that may be way more useful to understand.
  
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  - Chrobin@discuss.tchncs.de ⁨7⁩ ⁨months⁩ ago
    For that, you need Hilbert spaces, linear operators on them, a little spectral theory, …
    
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pipows@lemmy.today ⁨7⁩ ⁨months⁩ ago
I was not expecting a comment on a shitpost community to make quantum physics more clear to me

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Chrobin@discuss.tchncs.de ⁨7⁩ ⁨months⁩ ago
Many people are trying to give a definitive answer, and there are good theories, but honestly, it is still very much an open question. There are multiple interpretations and as people tend to do in popular science, some spread their opinion as a fact, but we don’t have one correct answer.

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gmtom@lemmy.world ⁨7⁩ ⁨months⁩ ago
☝️🤓

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andros_rex@lemmy.world ⁨8⁩ ⁨months⁩ ago
The Schrödinger equation is a multi variable second order partial differential equation. You end up with a “position operator” and a “momentum operator” (momentum is mass times velocity, so we focus on the velocity bit). Because of the way that taking a partial derivative works, you end up applying one you can’t get the other.

Idk that’s probably a terrible explanation, but it is really cool when you see how the math works.

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Sharkwellington@lemmy.one ⁨8⁩ ⁨months⁩ ago
☝️🤓

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Lojcs@lemm.ee ⁨8⁩ ⁨months⁩ ago
Perhaps the wave function always collapses no matter what, but the way it collapses changes? If there was no screen for the photons to interact with they’d continue to act like waves but since there’s a screen they collapse at some point dictated by the wave. And if you try to observe how they end up there you end up collapsing it earlier so where they go are dictated by the earlier state of the wave.

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