The meaning of 'Observer' in Quantum Physics

I usually don't start threads, but today I've seen two threads that insist of things not existing if we don't observe them. There are have been other threads in the past with the same concept.

To cut the long story short, when we say that "the wave function collapses when the particle is observed" we don't mean that a particle must be observed by a conscious entity like a human being in order to exist. What we mean is that if two particles collide, their wave function collapses and they behave like tiny bullets. If they don't collide, their wave function has not collapsed and so they behave like a wave. When the wave function collapses, reality emerges and we can measure the properties of matter. The "observer" is anything that can make a wave function collapse.

In other words, the universe is there, observer or not...so, can we all please relax with the threads about reality not existing when there is no human observer around?

(for the record, I ain't a physicist, only a programmer, but I know my way around physics).

If you don't believe me, then reading the physics forums may make you believe me:

www.physicsforums.com...

It has nothing to do with consciousness. The observer doesn't have to be human. If information about which slit the photon passes through is collected by a piece of equipment, the interference pattern is destroyed.

[edit on 27-3-2010 by masterp]

Yes thank you sir, this is a keen observation you are making.

I am glad that you are clarifying this for those whom may be confused about things.

When the wave/particles of "energy" 'collapse' they then become tangible 'matter'. When this very same energy is not collapsed, it is a form of energy wave or radiation. (Maybe I said it correctly)

In other words;

Q"When a Tree falls in the forest, and no one is around to hear it, does it make a sound?"

A"Yes the Tree always makes sound despite the fact no one heard it."

And another good one before I leave.

Q"Which came first the Chicken or the Egg?"

A"The Egg, because dinosaurs predate chickens and dinosaurs laid eggs."

Riddles do tend to have mundane remedies.

[edit on 27-3-2010 by muzzleflash]

While you're on the subject of "observer", perhaps you can comment on a point about the famous"Schrodinger's Cat" paradox.
I'm not a physicist in any way, and I've only got a layman's grasp of the concept.
However it seems to me that the usual presentation of the paradox completely disregards the fact that the eponymous cat itself counts as an observer, which means that the experiment is actually being observed before the physicist opens the box, and the paradox therefore falls down.
If I'm wrong on this point, can you put me right?

Originally posted by muzzleflash

Q"When a Tree falls in the forest, and no one is around to hear it, does it make a sound?"

A"Yes the Tree always makes sound despite the fact no one heard it."

[edit on 27-3-2010 by muzzleflash]

About this one. I saw someone explain it saying that sound is basically the vibration of sound waves on something that can interpret those waves as actual sounds. So if there is nothing in the forest to interpret the sound, then the waves just remain waves and aren't actually sound I dunno I'm not good at explainining physics concepts x.x

reply to post by masterp


Experiments have shown that consciousness is a factor because they have shown that the existence of knowledge is a factor.

In double slit experiments, if you measure what slit the particle uses but delete the information AFTER the experiment is complete, it does not collapse the wave. The existence of information for a consciousness observer changes the physical results.

So consciousness is the observer.

"by removing the information they have gathered so that it is not available from the time of the erasure going forward into the future), we can "change" the results of what we presume is a mechanically complete experiment"

www.bottomlayer.com...

3. Record the measurements at the slits, but then erase it before analyzing the results at the back wall.

Suppose we take our modified double slit set up -- with electron detectors at the slits -- and still leave everything intact. And we will still keep the electron detectors at the slits turned on, so that they will be doing whatever they do to detect electrons at the slits. And we will record the count at the slits, so that we will be able to obtain the results. But, we will erase the data obtained from the electron detectors at the slits before we analyze the data from the back wall.

The result upon analysis: an interference pattern at the back wall. Notice that, in this variation, the double slit experiment with detectors at the slits is completed in every respect by the time we choose to erase the recorded data. Up to that point, there is no difference in our procedure here and in our initial procedure ([pp. 15-17]), which yielded the puzzling clumping pattern. Yet, it seems that if we, in a sense, retroactively remove the electron detectors at the slits (not by going back in time to physically remove them, but only by removing the information they have gathered so that it is not available from the time of the erasure going forward into the future), we can "change" the results of what we presume is a mechanically complete experiment, so far as those results are determined by a later analysis, to produce an interference pattern instead of a clumping pattern. This is mind-boggling.

reply to post by DISRAELI


...suppose a scientist walks into the lab, closes the door behind him, and observes the dead/alive cat.

in this case, the quantum superposition has moved from the box to the lab itself and the to the scientist. although the scientist inside the lab has collapsed the function, outside of the lab the cat is still dead/alive.

this is a good example of how the quantum observer MUST BE on a "higher level" than the object being observed. you can imagine the collapse of schrodinger's cat function moving outward from the box -> to the lab -> to the building -> and continuing upward and outward in nested levels.

so then, the poster above that was talking about the necessity of information in the quantum process is correct. reality, both massive and energetic, is built from the bottom up.

quantum particles do not require a conscious observer. indeed, there are a whole series of observations that occur between the very tiny quantum level to our very large human level. but this does not mean that humans, and thus consciousness, is removed entirely from the quantum system.


__________
in fact, the most basic metaphysical model is the nomenonphenomenon, also known as objectsubject and observedobserver. there is LITERALLY no other way of describing reality while simultaneously existing within that reality.

and it is for this reason that i grow weary of BOTH the people that abuse quantum mechanical theory AND those whom try to extract consciousness out of the equation.

reply to post by Jezus


I knew within a few posts the New Agers would arrive to defend their little industry. Stop borrowing terms and concepts from science to inflate your contrived theories. If you must borrow something, make sure you fully and completely understand it. Anything short of that is manipulation of data and blatent deception.

Originally posted by masterp
I usually don't start threads, but today I've seen two threads that insist of things not existing if we don't observe them. There are have been other threads in the past with the same concept.

To cut the long story short, when we say that "the wave function collapses when the particle is observed" we don't mean that a particle must be observed by a conscious entity like a human being in order to exist. What we mean is that if two particles collide, their wave function collapses and they behave like tiny bullets. If they don't collide, their wave function has not collapsed and so they behave like a wave.

I agree with the point you are trying to make. A tree falling in the woods makes a sound whether anyone is there to hear it or not. I would only like to make one small correction to your statement:

"If they don't collide, their wave function has not collapsed and so they behave like a wave." is not technically correct. An electron or photon is still subject to wave-particle duality prior to the wave function collapsing so it's not entirely accurate to say it will behave like a wave before that happens. It MAY behave like a wave, or it may behave like a particle. Someone coined the term "wavicle" to describe it.

Also there is a widespread misunderstanding on the double slit experiment related to this topic, which wiki talks about that I'd like to point out here:

en.wikipedia.org...

It is a widespread misunderstanding that, when two slits are open but a detector is added to the experiment to determine which slit a photon has passed through, then the interference pattern no longer forms and the experimental apparatus yields two simple patterns, one from each slit, superposed without interference. Such a result would be obtained only if the results of two experiments were superposed in which either one or the other slit is closed. However, there are many other methods to determine whether a photon passed through a slit, for instance by placing an atom at the position of each slit and monitoring whether one of these atoms is influenced by a photon passing it. In general in such experiments the interference pattern will be changed but not be completely wiped out. Interesting experiments of this latter kind have been performed with photons[7] and with neutrons.[8]

In other words, there are other ways to "observe" without completely collapsing the wave functions, as the movie "What the Bleep do we Know" has popularized. And to SteveR's point that movie is a "new ager" distortion of real science.

[edit on 28-3-2010 by Arbitrageur]

Originally posted by masterp
It has nothing to do with consciousness. The observer doesn't have to be human. If information about which slit the photon passes through is collected by a piece of equipment, the interference pattern is destroyed.

But doesn't a piece of equipment necessarily have to be constructed by a conscious entity? Basically, the equipment serves as an extension of the person's consciousness. Not really groundbreaking, but a nice sidenote.

As an aside, I think we are still on the wrong side of quantum physics. We have a general understanding, but it seems like there is still something that is evading us. I have no idea what it is, I just have a gut feeling. But it could be a quantum gut feeling; if I wasn't here, I wouldn't feel it.

Originally posted by crazyinthemiddle

Originally posted by masterp
It has nothing to do with consciousness. The observer doesn't have to be human. If information about which slit the photon passes through is collected by a piece of equipment, the interference pattern is destroyed.

But doesn't a piece of equipment necessarily have to be constructed by a conscious entity? Basically, the equipment serves as an extension of the person's consciousness. Not really groundbreaking, but a nice sidenote.

Totally irrelevant and you can prove it with a thought experiment (please not a real one).

If the creator of the instrument dies, presumably so does his consciousness. Yet the instrument will continue to function irrespective of the consciousness of its creator.

Also, no an instrument doesn't have to be created by a conscious entity, we have robots building things all the time now, why can't they build instruments too?

reply to post by Arbitrageur


Your first example I'll give you credit for, but the second, if consciousness travels from a human to a machine, why not one more step to yet another machine?

As I said originally, we still have a long way to go until we can explain everything about everything. It is fun to hypothesis along the way though.

i am really starting to get annoyed with being ignored on these forums.

i was really looking forward to coming into this thread tonight and chatting it up with someone.....who knows?....maybe even *the OP*.


but no. of course. no one talks to the weird guy in the corner. did anyone even READ what i wrote?! no.


thanks for nothin' ATS.

[edit on 28-3-2010 by tgidkp]

Actually this harps back to the anthropic principle, that the reason the universe is the way it is, is that there are an infinite number of universes, this one just happens to have the right properties to support life.

Actually an observer is in fact any system of interaction.

however... if there was no one to obverse in other words consciousness, then who could say if it is one or the other, since there was no one there.

Image a court room, the jury deliberates, the returns a verdict. all the people inside the court room know the outcome. However anyone outside the court could not know the outcome, so the court room is in superposition.

when the doors open and the verdict is released... innocent say... the wave function collapses for all the observers outside the court and the reality is set in stone.

Hope this helps,

Korg.

Originally posted by tgidkp

did anyone even READ what i wrote?! no.

You were responding to me, when you first wrote, and thank you for that very patient response.
I would have thanked you before, but I was in bed and fast asleep at the time you posted, and I've only just got up.
You were explaining things in terms a layman could understand (or nearly understand- I'm still working on it), so thank you again for that.
PS Just below this edit box I can see the post from Korg Trinity. It doesn't show whether this is also a reponse to me- but if it is, my thanks to you as well.

The Observer is discovered FEB 12, 2072 and given the short title "The Umpass". It also becomes a strong link in the final conclusion that there is in fact a God (although not confirmed and therefore still debated). It's funny though because it was an Atheist Scientist that discovered the Umpass without knowing where that would soon lead. lol


(Of course when I say 'Discovered' I mean the article is published). And NO I'm not a freakin time traveler or a prophet. Just take what I say at face value or ignore it.

Originally posted by tgidkp
i am really starting to get annoyed with being ignored on these forums.

Chill, dude, we've all had posts ignored on these forums, don't take it personally. I read your post but didn't know how to respond to it, because I never heard of the nested levels you mentioned before. If you've got any sources about that I'd be interested in reading up on it.

And if you're looking for chat, did you try the chat button? You can wait a long time for a reply to posts here and sometimes never get one but you can get replies to your chat immediately, while it lasts. I think they are thinking of dropping the chat though.

Originally posted by DISRAELI
While you're on the subject of "observer", perhaps you can comment on a point about the famous"Schrodinger's Cat" paradox.
I'm not a physicist in any way, and I've only got a layman's grasp of the concept.
However it seems to me that the usual presentation of the paradox completely disregards the fact that the eponymous cat itself counts as an observer, which means that the experiment is actually being observed before the physicist opens the box, and the paradox therefore falls down.
If I'm wrong on this point, can you put me right?

In the famous Schrodinger's Cat hypothesis, the objects inside the box do not play any role in the 'observation'. When we say that we look into the box, we mean that we send a photon into it, thus collapsing the wave function of the particles inside the "box".

Originally posted by Jezus
reply to post by masterp

 

Experiments have shown that consciousness is a factor because they have shown that the existence of knowledge is a factor.

In double slit experiments, if you measure what slit the particle uses but delete the information AFTER the experiment is complete, it does not collapse the wave. The existence of information for a consciousness observer changes the physical results.

So consciousness is the observer.

"by removing the information they have gathered so that it is not available from the time of the erasure going forward into the future), we can "change" the results of what we presume is a mechanically complete experiment"

www.bottomlayer.com...

3. Record the measurements at the slits, but then erase it before analyzing the results at the back wall.

Suppose we take our modified double slit set up -- with electron detectors at the slits -- and still leave everything intact. And we will still keep the electron detectors at the slits turned on, so that they will be doing whatever they do to detect electrons at the slits. And we will record the count at the slits, so that we will be able to obtain the results. But, we will erase the data obtained from the electron detectors at the slits before we analyze the data from the back wall.

The result upon analysis: an interference pattern at the back wall. Notice that, in this variation, the double slit experiment with detectors at the slits is completed in every respect by the time we choose to erase the recorded data. Up to that point, there is no difference in our procedure here and in our initial procedure ([pp. 15-17]), which yielded the puzzling clumping pattern. Yet, it seems that if we, in a sense, retroactively remove the electron detectors at the slits (not by going back in time to physically remove them, but only by removing the information they have gathered so that it is not available from the time of the erasure going forward into the future), we can "change" the results of what we presume is a mechanically complete experiment, so far as those results are determined by a later analysis, to produce an interference pattern instead of a clumping pattern. This is mind-boggling.

No. They have done such experiments and they found that the presence of a conscious observer made no difference in the experiments.

www.abovetopsecret.com... Art bell s show covers this topic really well as he Interviews Robert Lanza. Theres even a link to the Sound files here) enjoy

Since deleting information affects the physical results after the experiment is complete, consciousness must be a factor.

Measure and delete the information – wave doesn’t collapse
Measure and keep information – wave does collapse

If the existence of data influences experimental results, consciousness must be a factor.

Data is not physically related to what it describes, data is an abstract concept that is only related to what it describes when it is interpreted by a conscious observer.

Originally posted by Jezus
3. Record the measurements at the slits, but then erase it before analyzing the results at the back wall.

Suppose we take our modified double slit set up -- with electron detectors at the slits -- and still leave everything intact. And we will still keep the electron detectors at the slits turned on, so that they will be doing whatever they do to detect electrons at the slits. And we will record the count at the slits, so that we will be able to obtain the results. But, we will erase the data obtained from the electron detectors at the slits before we analyze the data from the back wall.

The result upon analysis: an interference pattern at the back wall. Notice that, in this variation, the double slit experiment with detectors at the slits is completed in every respect by the time we choose to erase the recorded data. Up to that point, there is no difference in our procedure here and in our initial procedure ([pp. 15-17]), which yielded the puzzling clumping pattern. Yet, it seems that if we, in a sense, retroactively remove the electron detectors at the slits (not by going back in time to physically remove them, but only by removing the information they have gathered so that it is not available from the time of the erasure going forward into the future), we can "change" the results of what we presume is a mechanically complete experiment, so far as those results are determined by a later analysis, to produce an interference pattern instead of a clumping pattern. This is mind-boggling.

[edit on 28-3-2010 by Jezus]