ok, double slit experiment, NO TANGENTS

[parson]

Parson I cannot believe you couldn't write a simple biog - you are one effusive mo fo

i don't wanna write about myself

[ikarai]

hmmm. its definately an interesting one.

not gonna pretend to a complete understanding of this but how it seems to me is, sub atomic entities displaying properties of both particles and waves seems to be part of their makeup.. light itself behaves in this way and it's documented that atoms and molecules display properties of both too. In this article http://en.wikipedia.org/wiki/Wave%E2%80 ... le_duality they cite the double slit experiment as early as the late 1800s, so knowledge of this behaviour is not new or ground breaking.

Regarding the mutable nature of the results of the experiment, I can't help but think that it's our own human perception of the events which changes, rather than the events themselves. Considering it is an inherent part of the make up of matter that it displays the behaviour of particles and waves, is it not feasible that it is akin to seeing something in your periferal vision, and that once you bring it into focus, what you see seems essentially different... likewise, the entaglement thing is just a way of looking without really looking. You're still partaking of a certain arrangement of energy, just in different forms. I'm a bit drunk now so i may be chatting utter nonsense tho.

[fuagofire]

god did it

[slothrop]

i love Dr. Quantum

also - the fact that you need to perceive photons bouncing off something in order to perceive the thing in this physical reality does make it a little hard to observe electrons.

Bear in mind that electromagentic fields are carried by photons, so if you have something effected by an electric or magnetic field you're doing it by hitting it with photons. If I was going to build an electron detector, my naive first attempt would be building something that checks for the tiny current produced by an electric charge moving through my slit, and I'd do that by looking for the magnetic field that produces. But doing that would involve having something with its own magnetic field (otherwise it wouldn't be effected by the field from the electron) and that would mean that it would barge the electron around as well.

(Actually, I guess the really naive option would be to use a bubble chamber, but firing your electrons through a bit of liquid hydrogen would pretty obviously have an effect on it as well.)

[masstronaut]

In this article http://en.wikipedia.org/wiki/Wave%E2%80 ... le_duality they cite the double slit experiment as early as the late 1800s, so knowledge of this behaviour is not new or ground breaking.

Being new is not the point. The point is, what are the implications?

Considering it is an inherent part of the make up of matter that it displays the behaviour of particles and waves, is it not feasible that it is akin to seeing something in your periferal vision, and that once you bring it into focus, what you see seems essentially different...

Well hang on, it's experiments like these that demonstrate that matter can behave as both waves and particles in the first place.
The point is that 'bringing it into focus' - i.e. making an observation about where a particle is at a given time - seems to actually change the particle's behaviour.

likewise, the entaglement thing is just a way of looking without really looking.

Yes it is. And the reason for this is to allow a measurement to be taken that does not directly involve the photon being measured, so you're not bouncing things off it or taking energy from it. This let's you also take it to the next stage where the ability to extract the information from the measurement about position is 'erased'. So if we can read the information from the observations of position, we see particle behaviour, and yet if the observation is still made but we can't read it, we get waves again - the interference pattern returns. It's pretty nuts.

I'd say that information is the key here. If the information about the photons position at a given time exists it has to sort itself out and behave like a particle. If the information doesn't exist it can go ahead and act like a wave.

[slothrop]

But basically, to know that something's there, it has to have some effect on your detector, and having an effect on your detector means that your detector must have an effect on the thing - they have to interact with each other.

Well check this out.

This experiment uses entangled pairs of photons to carry out the measurements, so there is no direct physical interaction on the photons that go through the slits, at least not one that anyone can account for at present. This still produces the expected particle-like behaviour.

OK, you might say that messing with an entangled partner has an effect on the photon. However, when the experiment is changed so that the observation is still carried out but the ability to extract information from it is 'erased' - the interference pattern returns.

http://en.wikipedia.org/wiki/Quantum_eraser_experiment

Interesting, will read later.

Hmmm... this seems to be the crux of the issue:
http://en.wikipedia.org/wiki/Measurement_problem

[ikarai]

i think what i'm trying to say is, how can we be sure it's the behaviour of the particles that is changing, and not just our ability to perceive them in a certain way?

[ikarai]

but i agree it is definately fucked up that certain elements of information we can glean appear to be mutually exclusive.

[masstronaut]

i think what i'm trying to say is, how can we be sure it's the behaviour of the particles that is changing, and not just our ability to perceive them in a certain way?

Well maybe that's a whole other philosophical can of worms you're getting at. But the double slit thing shows that you fire photons or electrons at a board with slits in it and depending on how you observe them they seem to behave in different ways, you'll see a different pattern where they end up.

Are you saying that somewhere there is another pattern being made on the board it's just you can't see it because you have decided to make a certain observation? That's hardly any less strange. In fact that's actually very similar to one of the standard interpretations of the results of these experiments.

[ikarai]

yeah, pretty much... i guess. lol. where does quantum duality end and existential duality begin? As you say, it's just as wierd to consider that our minds have unknowingly closed themselves to a particular facet of reality through a conscious choice as it is to posit that the same choice has actively influenced the nature of reality.

[parson]

our minds have unknowingly closed themselves to a particular facet of reality through a conscious choice as it is to posit that the same choice has actively influenced the nature of reality.

yesssss

[psyolopher]

I like this one:
http://www.youtube.com/watch?v=BWyTxCsIXE4&NR=1

lol

[nousd]

our minds have unknowingly closed themselves to a particular facet of reality through a conscious choice as it is to posit that the same choice has actively influenced the nature of reality.

yesssss

Yes what? This^ doesn't make sense
but I think that you're hoping that it means that one's mind
(thru observing , ie gathering data) determines reality.

My knowledge is that nothing is outside what is happening (reality?)
including mind...
mind is happening just as is everything else in an equitable matrix of events.
Just because supposed "anomalies" are present, doesn't mean that mind (I?) caused them.

[parson]

our minds have unknowingly closed themselves to a particular facet of reality through a conscious choice as it is to posit that the same choice has actively influenced the nature of reality.

yesssss

Yes what? This^ doesn't make sense
but I think that you're hoping that it means that one's mind
(thru observing , ie gathering data) determines reality.

it makers perfect sense.

he's saying that reality is fuckin weird, but people pretend like its not. and since people pretend like weird shit doesn't happen, it influences the nature of reality.

[nousd]

Sorry, hadn't finished when you posted.

Do you not agree that the language in bold doesn't make sense?
And that pretending is part of reality?

[parson]

does it make sense when you consider my interpretation?

[parson]

yeah, pretty much... i guess. lol. where does quantum duality end and existential duality begin? As you say, it's just as wierd to consider that our minds have unknowingly closed themselves to a particular facet of reality through a conscious choice as it is to posit that the same choice has actively influenced the nature of reality.

it also makes more sense when you read the whole sentence

[nousd]

Sorry, rushed again, yeah OK see point.


OK now what are you trying to explain?

[parson]

i love it when i'm so high that i read something i wrote when i wasn't high and i can't understand it at all

[parson]

yeah it just didn't make sense because i cropped the sentence. i guess i shoulda quoted the whole thing and bolded that part.