Double slit experiment

[Kaolccips]

Excuse the childness of the video. At least it's easy to understand

http://youtube.com/watch?v=6Q4_nl0ICao

I've known about this experiment for quite awhile. Not sure if you guys have had a post over it.

 

[arrfep]

Phew. For a second I thought this was a witty response to the "What would you do with a million dollars?" question.

 

[gorobei]

damn wavist propaganda, trying to besmirch the holy word of particles.

fun stuff, but the whole quantum uncertainty miasma was what turned me off of physics as a major in college.


edit: nice to see John Astin still getting work.

 

[Kaolccips]

No one else finds this completely mind blowing? First time I seen this it completely changed my whole view on the world.
No longer does "If a tree falls and no one is around to hear it, does it make a noise?" seem like a completely retarded question to me.

This blows me away.

 

[JohnCU]

Originally posted by: Kaolccips
No one else finds this completely mind blowing? First time I seen this it completely changed my whole view on the world.
No longer does "If a tree falls and no one is around to hear it, does it make a noise?" seem like a completely retarded question to me.

This blows me away.

agreed. it's insane when you think about it. so much we don't know. especially when you get into wave function collapses after "observation" (i think i said that right).

 

[pyonir]

Originally posted by: arrfep
Phew. For a second I thought this was a witty response to the "What would you do with a million dollars?" question.

:shocked:

 

[Atomic Playboy]

Originally posted by: arrfep
Phew. For a second I thought this was a witty response to the "What would you do with a million dollars?" question.

:thumbsup:

As for the video... well, Youtube is blocked at work. But if it is what I think it is, I've read about it, and it's fucking crazy yo. Then again, time is an illusion. And apparently, light is psychic. Which makes sense... it's the fastest thing in the universe, obviously it's going to beat us to the punch.

 

[Suspicious-Teach8788]

As a materials scientist, I don't know how many times we've had go to through diffraction and constructive/destructive interference. It's been too many, but umm... I don't know how mind blowing this is to everyone, but it's a fundamental to my x-rays class and it's just average to me.

 

[ConstipatedVigilante]

What the fuck? So then, what's my monitor doing when I'm not looking at it? Eh?!!?!?

 

[biggestmuff]

That's crazy. That's the first time I've seen that. However, they really need to rename that experiment.

 

[halik]

Originally posted by: Kaolccips
No one else finds this completely mind blowing? First time I seen this it completely changed my whole view on the world.
No longer does "If a tree falls and no one is around to hear it, does it make a noise?" seem like a completely retarded question to me.

This blows me away.

First time i heard about it I was absolutely blown away; that and quantum entanglement is absolutely amazing to me.

 

[thecrecarc]

omg magic!

 

[destrekor]

holy shit. I knew nothing about quantum physics prior to this, and well still don't, but that's kind of mind blowing. I always heard that you change the result of quantum experiments by measuring it, but how the hell does that happen?

and is this merely by 'observing', or some kind of measurement? Say, are the first results determined by nothing observing it and merely observing the result after the test is finished, by looking at a plate that displays where the electrons hit or did not hit?

and, is quantum mechanics dealing with electrons, or with light? I always thought it was light/photons.

+

 

[destrekor]

Originally posted by: DLeRium
As a materials scientist, I don't know how many times we've had go to through diffraction and constructive/destructive interference. It's been too many, but umm... I don't know how mind blowing this is to everyone, but it's a fundamental to my x-rays class and it's just average to me.

can you explain why? even if I knew about this and expected it to occur, not knowing the fundamental reason why would blow my mind.
So, is it only average to you, because you got tired of your mind spazzing out over the fact that you didn't know why, and is now just programmed to think 'meh' so that it doesn't get all erratic again?
If that's the case, that makes sense. I can't function like that though, my brain is constantly striving to find the reasons for why things are the way they are... but that's because I really like discussing different theories. I like engaging in that kind of thought/conversation.

+

 

[ja1484]

Anyone looking for a good read with a surprising amount of factual information on quantum physics (although the book itself is fiction), should read Michael Crichton's "Timeline".

One of the things I love about his work is how while technically fiction, he makes it so scarily plausible. This is because he always bases his stories on new or emerging technologies or fields, and does research on the actual science before creating his fiction story-line around the subject. He took this to the ultimate extreme in his latest novel Next, where the author's introductory note simply reads:

"This book is fiction, except for the parts that aren't."

Originally posted by: destrekor
and, is quantum mechanics dealing with electrons, or with light? I always thought it was light/photons.

+

Technically, Quanta, which are particles that are, theoretically, smaller than subatomic - in other words, smaller than electrons, protons, quarks, etc.

 

[spidey07]

Originally posted by: destrekor

Originally posted by: DLeRium
As a materials scientist, I don't know how many times we've had go to through diffraction and constructive/destructive interference. It's been too many, but umm... I don't know how mind blowing this is to everyone, but it's a fundamental to my x-rays class and it's just average to me.

can you explain why? even if I knew about this and expected it to occur, not knowing the fundamental reason why would blow my mind.
So, is it only average to you, because you got tired of your mind spazzing out over the fact that you didn't know why, and is now just programmed to think 'meh' so that it doesn't get all erratic again?
If that's the case, that makes sense. I can't function like that though, my brain is constantly striving to find the reasons for why things are the way they are... but that's because I really like discussing different theories. I like engaging in that kind of thought/conversation.

+

We still don't fully understand wave/particle duality. Quantum does a pretty job. But seriously, how the hell can you have something with a spin of 1/2??? Does not compute.

 

[Kaolccips]

Originally posted by: destrekor
holy shit. I knew nothing about quantum physics prior to this, and well still don't, but that's kind of mind blowing. I always heard that you change the result of quantum experiments by measuring it, but how the hell does that happen?

and is this merely by 'observing', or some kind of measurement? Say, are the first results determined by nothing observing it and merely observing the result after the test is finished, by looking at a plate that displays where the electrons hit or did not hit?

and, is quantum mechanics dealing with electrons, or with light? I always thought it was light/photons.

+

Basically what it comes down to is particles on the quantum level somehow "know" when they are being observed, and when they aren't. Which basically means is actually IS possible that a tree falling with nothing around to hear it, can actually make no sound whatsoever.

The video explains it better than I can. Basically when not being watched, a particle on the quantum level will take every possible route. But if you try to measure/observe it then it will go back to behaving how it is suppose to.

Originally posted by: spidey07
We still don't fully understand wave/particle duality. Quantum does a pretty job. But seriously, how the hell can you have something with a spin of 1/2??? Does not compute.

Some actually take more than 180 to turn back to original face. (Not sure how to explain it, i'm tired).
So it takes something like 1 1/2 turns for it to make a complete rotation. Wtf?


Another good video to watch that will trip you out.

What the !@#$ do we know?
http://youtube.com/watch?v=SrKvzPXULME&feature=related

 

[spidey07]

Kaolccips - a spin of 1/2 means it has to be rotated 720 degrees to get back to the original face.

 

[Jeff7]

Originally posted by: ConstipatedVigilante
What the fuck? So then, what's my monitor doing when I'm not looking at it? Eh?!!?!?

Watching you masturbate, of course.

Originally posted by: biggestmuff
That's crazy. That's the first time I've seen that. However, they really need to rename that experiment.

Ok, let's see here......ok, the waves are going through the slits, penetrating them.

How about "the double penetration experiment"? That sounds perfectly benign.



And I think that this video's explanation is the sort of thing from which some people get the idea that our observation of the Universe somehow changes it.
The video says that "observing" the electrons in motion changed their behavior.
The observation itself wasn't what caused the change in behavior, as I understand it, but in fact, it's the conditions required to allow observation which would be the problem. If you want to look at something, you need to shine light on it. In the macro world, that's just fine - shine a light on a wall, and the wall won't change appreciably. But start bombarding an electron with photons, and it's going to go nuts. I think that that is where the change in behavior actually comes from.

 

[Analog]

The whole point of the observer making the quantum effect choose a state may be a bit off kilter. Basically, the way I interpret it is that we cannot know both the position and momentum of a particle (electron et al), at the same time. The reason is, that we are at the physical limit of detection of such particles. I.e. its like using a baseball bat to figure out how many baseballs are in a canvas sack - the bat is going to "mess up" the baseballs because it interacts with what it is you want to measure. Ideally, you'd want to measure with something that has essentially no interaction with what you're measuring - i.e. a radar device to measure a car's speed. But we have no such device at these geometries, and therefore, the measurement can never reveal both position and momentum. So observation 'messes up' the measurement. Where's Silverpig when you need him!

 

[BrunoPuntzJones]

Originally posted by: Analog
The whole point of the observer making the quantum effect choose a state may be a bit off kilter. Basically, the way I interpret it is that we cannot know both the position and momentum of a particle (electron et al), at the same time. The reason is, that we are at the physical limit of detection of such particles. I.e. its like using a baseball bat to figure out how many baseballs are in a canvas sack - the bat is going to "mess up" the baseballs because it interacts with what it is you want to measure. Ideally, you'd want to measure with something that has essentially no interaction with what you're measuring - i.e. a radar device to measure a car's speed. But we have no such device at these geometries, and therefore, the measurement can never reveal both position and momentum. So observation 'messes up' the measurement. Where's Silverpig when you need him!

Not the analogy I would have used, but the latter part is good

Heisenberg was pulled over by a cop.

The cop says, "Sir, do you know how fast you are going?"

To which Heisenberg replies, "No, but I know where I am!"


Announcer: "And horse number 3 wins in a quantum finish!"
Professor Farnsworth: "No fair! You changed the outcome by measuring it!"

 

[spidey07]

Originally posted by: Analog
The whole point of the observer making the quantum effect choose a state may be a bit off kilter. Basically, the way I interpret it is that we cannot know both the position and momentum of a particle (electron et al), at the same time. The reason is, that we are at the physical limit of detection of such particles. I.e. its like using a baseball bat to figure out how many baseballs are in a canvas sack - the bat is going to "mess up" the baseballs because it interacts with what it is you want to measure. Ideally, you'd want to measure with something that has essentially no interaction with what you're measuring - i.e. a radar device to measure a car's speed. But we have no such device at these geometries, and therefore, the measurement can never reveal both position and momentum. So observation 'messes up' the measurement. Where's Silverpig when you need him!

Given your sig you may understand. That's where the particle accelerators come into play - they don't measure/observe anything. They measure/observe the effects after the event and from there we work our theories and equations.

I don't know, it's been so long since I've given this stuff much thought but it was a hobby of mine. But if I recall quantum mechanics takes into account heisenbergs uncertainty, heck the equations are built around it. This is why I stated earlier that we haven't really mastered the wave/particle duality and why string theory is trying to explain it.

With great uncertainty.

 

[Eeezee]

Originally posted by: gorobei
damn wavist propaganda, trying to besmirch the holy word of particles.

fun stuff, but the whole quantum uncertainty miasma was what turned me off of physics as a major in college.


edit: nice to see John Astin still getting work.

Astounding advances have been made in Hidden Variable theory, which is the idea that quantum weirdness doesn't exist but that there are hidden variables that cause the "weirdness" that we see.

The problem is that it doesn't make any new predictions, so no one is using it except for the theorists that put so much time into developing it. It was designed to properly explain the weirdness that we see in quantum mechanics.

It's an awesome experiment

 

[Eeezee]

Originally posted by: ja1484
Anyone looking for a good read with a surprising amount of factual information on quantum physics (although the book itself is fiction), should read Michael Crichton's "Timeline".

One of the things I love about his work is how while technically fiction, he makes it so scarily plausible. This is because he always bases his stories on new or emerging technologies or fields, and does research on the actual science before creating his fiction story-line around the subject. He took this to the ultimate extreme in his latest novel Next, where the author's introductory note simply reads:

"This book is fiction, except for the parts that aren't."

Originally posted by: destrekor
and, is quantum mechanics dealing with electrons, or with light? I always thought it was light/photons.

+

Technically, Quanta, which are particles that are, theoretically, smaller than subatomic - in other words, smaller than electrons, protons, quarks, etc.

That's not quite right... quantum mechanics deals with electrons, photons, quarks, protons (which are groups of quarks), etc. It precisely describes the Zeeman effect, the Stark effects, ferromagnetism (ie why iron can be magnetized), etc.

You can derive all of chemistry from quantum mechanics. In fact, that's what a fair number of material science physicists do; they derive chemicals that had previously been undiscovered by applying the variational principle (which is a good way to approximate the wave function of particle or group of particles) and basically letting a computer tell them possibly molecular compositions.

 

[Eeezee]

Originally posted by: Kaolccips

Originally posted by: destrekor
holy shit. I knew nothing about quantum physics prior to this, and well still don't, but that's kind of mind blowing. I always heard that you change the result of quantum experiments by measuring it, but how the hell does that happen?

and is this merely by 'observing', or some kind of measurement? Say, are the first results determined by nothing observing it and merely observing the result after the test is finished, by looking at a plate that displays where the electrons hit or did not hit?

and, is quantum mechanics dealing with electrons, or with light? I always thought it was light/photons.

+

Basically what it comes down to is particles on the quantum level somehow "know" when they are being observed, and when they aren't. Which basically means is actually IS possible that a tree falling with nothing around to hear it, can actually make no sound whatsoever.

The video explains it better than I can. Basically when not being watched, a particle on the quantum level will take every possible route. But if you try to measure/observe it then it will go back to behaving how it is suppose to.

Originally posted by: spidey07
We still don't fully understand wave/particle duality. Quantum does a pretty job. But seriously, how the hell can you have something with a spin of 1/2??? Does not compute.

Some actually take more than 180 to turn back to original face. (Not sure how to explain it, i'm tired).
So it takes something like 1 1/2 turns for it to make a complete rotation. Wtf?


Another good video to watch that will trip you out.

What the !@#$ do we know?
http://youtube.com/watch?v=SrKvzPXULME&feature=related

NO, that movie is mostly bullshit. They get more than a few things wrong, and a lot of it is trying to relate psychology to quantum mechanics. It was, in fact, funded by some sort of weird religious group.