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The Double Slit Experiment and frequencies

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The double slit experiment is interesting, indeed. However, one must be careful about what kind of implications one draws out of this. Often quantum mechanics (and the double slit experiment) is misunderstood. The first mistake, and perhaps the largest one that makes a lot of bogus claims flow around, is the misunderstanding of what an observation actually is. Lets work our way through a few examples:

Say you want to measure the temperature in a cup of coffee. How are you going to do this? Obviously you must put a device inside, such as a thermometer, in order to measure the temperature. When you put this thermometer inside, you will slightly affect the system because the thermometer has a temperature and thus an energy of its own that will disrupt the original state of the system. We have not changed the outcome of events simply by passively looking at the cup, but we have made matter interact with eachother in order to make the measurement, and thus because of this interaction the system is changed from whatever it was originally.

When you look at the wall, what is really happening is that photons of light first interact with the wall, bouncing off of it, before they reache your eyes and are interpretated by your brain. The observation of the wall is in reality interaction between photons and atoms in the wall. Without this interaction - no wall to be seen.

With this in the back of our head, lets go back to the double slit experiment. The observation that leads to the collapse of the wave function is nothing else than matter interacting. Say, if we shoot electrons through the slits and we wish to determine what slit they actually move through, we must let for example photons of light interfere with the electrons passing through, thus defining their state because the photons interact with the electrons. The collapse of the wave function doesn't happen simply because our consciousness passively is there to observe it, but the electrons are being affected because we must use something physical to perform the observation in the first place. This physical interaction is what constitutes an observation, and it is what creates the collapse. This can happen even though no conscious agent is present, in a sealed off lab with no labrats there at all.

What people try to do in this quantum quackery new age nonsense is to make it seem like that the mere act of looking at something changes it, but it doesn't. It is the tools we use to measure something that makes the interaction, and that is a huge difference. If we could shrink ourselves down to the size of an electron, and sit there passively to observe it, then we would truly see what was going on. But we obviosuly can't get that small, I am sorry, so we use instruments that interrupt what is naturally going on in the system. No mystical mumbo jumbo is going on here, it's just our inadequate way of observing things at so small scales. The wave function collapse is, again, simply that particles in so called superposition is forced to interact with its immediate environment in such a way that the wave function collapses down to one spesific state.

This is the physics behind it, and those who try to make quantum mechanics imply that we somehow create reality should explain to the rest of the world why the simple physics behind it is not to blame. As a final note, I have simply shown how the double slit experiment can't and should not be used to draw such spiritual conclusions as people often do, but I have not disregarded that such spiritual phenomena is possible (so don't go shooting me with being close minded or something).

Peace.
 
Good reply Citta. I highly recommend for you to read the book "Quantum Reality" written by particle physicist and, oddly enough, a proponent of psychedelics: Nick Herbert. It is a tad outdated due to it being written in the 80s. It can also be a little difficult to read or conceptualize concepts in the books (I mean... it is quantum physics, haha). But the book is based around explaining the 8 main theories that are drawn from the EXACT SAME DATA gained from experimentation. He explains how physicists interpret the data differently, etc and explains basic and somewhat more complex ideas in physics.

Definitely worth a read if you're interested in learning more.

Have fun!
 
Citta wrote:
What people try to do in this quantum quackery new age nonsense is to make it seem like that the mere act of looking at something changes it, but it doesn't. It is the tools we use to measure something that makes the interaction, and that is a huge difference.
..the measuring instruments are an extension of our consciousness ('eyes')
an act by a sentient being is still required to perform a measurement..
also, until a set of eyes read the measurement, there is no 'result' that can be proven..
.
 
nen888 said:
Citta wrote:
What people try to do in this quantum quackery new age nonsense is to make it seem like that the mere act of looking at something changes it, but it doesn't. It is the tools we use to measure something that makes the interaction, and that is a huge difference.
..the measuring instruments are an extension of our consciousness ('eyes')
an act by a sentient being is still required to perform a measurement..
also, until a set of eyes read the measurement, there is no 'result' that can be proven..
.

To the obviousmobile! What is your point, exactly? What I have made a case for is how it is not correct to somehow use quantum mechanics to imply the fact that consciousness begets matter, as many people do. I think I have made it quite clear that quantum mechanics do not, by default, imply such a thing with the fact that 'observation' in quantum mechanical terms simply refers to a natural physical interaction between for example a photon and an electron, that in principle is quite similar to the disturbance you will do to the temperature of a cup of coffee upon measurement.

We always have to change the state of a system in order to make a measurement of it, this is an obvious matter of fact of physics. How could we even not change the state of a system upon measuring something? It is impossible. In the case of the temperature in a cup of coffee, the disturbance will be so small that for all practical purposes it won't matter, but when we're down on the scale of fundamental particles it will make a huge difference because of the incredibly small sizes involved. How does any of this imply that the mere act of looking at things changes it? Because it doesn't - the mere act of looking at the cup of coffee doesn't change that system, and the mere act of looking in terms of measuring something in the cup will create physical interactions that changes the system.

Again, it is the tools, the physical tools, we use to make a measurement that creates an interaction, not our passive consciousness in itself.
 
Citta wrote:
What is your point, exactly? What I have made a case for is how it is not correct to somehow use quantum mechanics to imply the fact that consciousness begets matter, as many people do. I think I have made it quite clear that quantum mechanics do not, by default, imply such a thing with the fact that 'observation' in quantum mechanical terms simply refers to a natural physical interaction between for example a photon and an electron, that in principle is quite similar to the disturbance you will do to the temperature of a cup of coffee upon measurement.
..it's a philosophical point, and not one simply made by daft new agers..your blanket interpretation of all philosophy regarding 'consciousness' and the observer as being new age whacko is not correct..a measuring instrument, like the eyes, interacts with the environment, but it is not passive..
..the philosophical idea that consciousness is required for the universe, or vice versa (such as the anthrophic principle) are not the works of new age idiots
can you provide some reference material as to the interpretations of 'observation' in Quantum Physics, particularly the Copenhagen interpretation..?
 
..well, seeing as there are no references yet from the scientists, i found this interesting thesis..The Role of the Observer in Interpretations of Quantum Mechanics by Paul Sonenthal

The role of the observer is central to Everett's reformulation of quantum
mechanics. For this reason alone, Everett's theory offers valuable insight. In fact, the
observer is so important in this interpretation that Everett goes so far as to refer to
conventional quantum mechanics as the "external observation'' formulation . Unlike
other interpretations, the observer, according to Everett, is included within the
wavefunction of the universe and Everett provides an explicit definition for the qualities
of the observer:
"As models for observers, we can, if we wish, consider automatically
functioning machines, possessing sensory apparatus and coupled to
recording devices capable of registering past sensory data and machine
configurations. We can further suppose that the machine is so constructed
that its present actions shall be determined not only by its present sensory
data, but by the contents of its memory as well."

I have tried to show that the role of the observer is exceedingly relevant to
evaluating interpretations of quantum mechanics. Whether we are aware of it or not, our
understanding of the human mind is influential in our formulation of scientific theories. A
naive conception of the mind has given rise to unnecessary confusion and speculation in
quantum mechanics..
..i'm still working out it's final position..:)
 
This is absolutely my favorite science experiment I have ever heard of, when I saw this before it blew my mind, I think about it often.
 
Everyone keep in mind that everything in the quantum world revolves around probabilities.

Sure your eyes may be an M device, but the quantum particles have a higher probability to be located where they are right this instant (the reason most things make sense). Of course, there's a very very small probability of the particle appearing somewhere else in space or time, but very unlikely: if you've taken stats you'll be familiar with the bell curve which is basically the form of probability these things follow.

You never know... you may end up on Venus someday... (given a few trillion trillion years).
 
Good post Citta, and though I agree with you on most of your points, if not all, I still must play the devil's advocate in response to this "problem." :)


(in reference to experiments with light)
This video didn't adequately explain the experiment, and skipped an awesome and most confusing piece of information. When they first employed the photon detectors, the observation was of a pattern of no diffraction, just straight shots through the slits. Obviously in states of bafflement, to disprove the notion that merely observing influenced the photons to act differently, it was decided that they would leave the photon detectors on, but to disable the detectors from collecting any data. The pattern subsequently observed was a diffraction pattern. This proves that the instruments being used were not influencing the photons to cease diffraction.

A little off topic, but I've had this talk with my father a few times, a brilliant man with an awesome understanding of physics and quantum mechanics, and every time I am just blown away by the implications and resort to just shaking my head in disbelief. But I digress...

By just sending photons through two slits, you will observe probability distribution, because the measurement was made after they had passed through the slits. This implies that there was no particle until the measurement was made. There was only probability, and therein lies your diffraction pattern.

By sending photons through two slits, and making measurements as they pass through the slits, you will observe a physical particle, and physical particles move in straight lines. This implies there is both particle, and probability. Therein lies the two line pattern.

I do not know near as much about quantum mechanics as a few people I know, but I do know that you can't have quantum mechanics without the human mind, I think its plausible that the external universe is somehow entangled in the human mind. It doesn't mean I apply divinity to the universe, I accept it just as I accept the universe. It just is.
 
Intriguing, I'd like to know more, such as what was used to observe this and how it affected the system. Did the camera (obviously not any ordinary camera) affect the electron being observed? And if so, how?
 
Orion said:
Intriguing, I'd like to know more, such as what was used to observe this and how it affected the system. Did the camera (obviously not any ordinary camera) affect the electron being observed? And if so, how?

See the reply from Citta:
Citta said:
What I have made a case for is how it is not correct to somehow use quantum mechanics to imply the fact that consciousness begets matter, as many people do. I think I have made it quite clear that quantum mechanics do not, by default, imply such a thing with the fact that 'observation' in quantum mechanical terms simply refers to a natural physical interaction between for example a photon and an electron, that in principle is quite similar to the disturbance you will do to the temperature of a cup of coffee upon measurement.
So to answer your question: yes, the electron was affected by the 'camera'.


Kind regards,

The Traveler
 
The Traveler said:
So to answer your question: yes, the electron was affected by the 'camera'.

I've always had quantum questions--perhaps you're just the person to answer them.

As a biochemist I spent a lot of time in introductory courses being told how certain reactions produce (or absorb) X kcal. of energy, which is then passed to (or received by) the adjacent set of molecules plus enzyme to energetically allow for the next reaction....and that "explanation" has always seemed facile to me**.

If anyone knows, I'd like to know:

1) In chemical reactions, is energy released and absorbed mostly KINETICALLY, or via photons? If it were kinetic, that would make sense to me, because I could imagine molecules being smashed together, thus over-riding electron repulsion, and allowing for the recombination of atoms from the high-energy state achieved by smashing them together. I have a bit more trouble imagining how the transfer of a photon is "transduced" in such a manner as to promote a chemical reaction (which MUST, in any case, somehow involved molecules coming CLOSE to one another).

2) Imagine an apparatus which can emit a single "photon" at a time. Does that photon go off in...one direction, and not another? Might it be detected "to the north" and thus NOT be detected "to the south?" The reason I ask this is because, in biochemical energetics (which sometimes involve "countable" numbers of molecules, certainly, "discrete" molecules--vs a typical chemistry experiment using a "beaker full" of the relevant molecules), the energy released from one reaction always seems to get USED WHERE IT'S NEEDED for another reaction--and if a photon goes only in a single direction, it would seem to have a high probability of "missing" an adjacent molecule that "needs it" for it's subsequent reaction.

I've asked people who ought to know the answers to these things, and no one so far has really supplied a solid answer that I could be satisfied with. In either case (kinetics or directional photon transfer) it seems to me that a significant proportion of energy (i.e., a significant proportion of quanta, among all quanta involved) would be LOST if it went in the wrong direction, but biochemical bookkeeping seems to suggest that it's NOT lost--that released energy always seems to get to where it's needed....


**Indeed, the function of enzymes has always thought to involve "holding" the reacting molecules in the correct relative position, in order to lower activation energy. AND, whenever energy is released in these situations, it always seems to then be USED in exactly the manner it's NEEDED. What I'm puzzled about is LOCATION--how does the energy always seem to get exactly where it's supposed to go?
 
thanks fractalyzed for the info..

..my philosophical point was that the camera doesn't exist without human consciousness..it is an extension..similarly the eyes may detect the position of a photon, but they are directed by a sentient observer..where is the proof that any probability waveform 'collapses' in a completely 'inert' system..i.e. one without sentient self-obersvational ability..?
..even wikipedia quotes Capra as saying:
"The crucial feature of atomic physics is that the human observer is not only necessary to observe the properties of an object, but is necessary even to define these properties. ... This can be illustrated with the simple case of a subatomic particle. When observing such a particle, one may choose to measure — among other quantities — the particle's position and its momentum"

..while i truly do appreciate your expert opinion Citta, i'm a references kinda guy..that's how new age garbage is sorted from scientific gems..science without philosophy is directionless and contextless..
.
 
nen888 said:
..my philosophical point was that the camera doesn't exist without human consciousness..it is an extension..similarly the eyes may detect the position of a photon, but they are directed by a sentient observer..where is the proof that any probability waveform 'collapses' in a completely 'inert' system..i.e. one without sentient self-obersvational ability..?

I understand your philosophical point, and it's nothing wrong with entertaining it. I have not attacked a philosophical point like this per se, but I have tried to show why people shouldn't use quantum mechanics to straight out claim that we create our reality, that consciousness begets matter or something similar - and that one must be careful with what kind of implications one draws from the double slit experiment.

Quantum mechanics doesn't say that we create our reality at all, and thus shouldn't be used to back up such and similar claims. It's just wrong, and I think you can agree. So I didn't come in here to discuss philosophy (that is not my area of expertise anyway), but to set the record straight with some science from the real area that is quantum mechanics.

Furthermore, the quote from Capra doesn't say anything, but is actually pretty obvious. After all, humans "invented" physics to understand the world, and everything like mass, space, time and other quantities are defined operationally by how we measure them. Position is measured with a properly calibrated meter stick. Time is measured with a properly calibrated clock. They are simply ingredients of the mathematical models we use to describe observations, and they are further used to predict other observations. Where does any of this imply that we create reality, or that consciousness begets matter? It's a non sequitur.

The same applies to quantum "states". They also are simply a part of a theory that we have more or less "invented" in order to describe and make sense of observations. The wave function is an abstract mathematical tool, and is not associated with any one particular particle, but rather associated with the probability for finding a particle at a particular place.

The vast majority of physicists and neuroscientists give no credence to the new paradigm of quantum consciousness, and Nobel laureate Leon Lederman speaks for most when he calls it "moo shoo physics".

Until someone can give some real plausible answers to how exactly consciousness "collapses the wave function", that it begets matter or that we create our reality and give evidence for such claims (evidence for such claims is pretty much non-existent), they simply stand without any foundation and can only be speculated about in philosophical terms.

So again, it is not consciousness that collapses the wave function, but the physical measurements of a completely in-sentient apparatus. The experiment can be run, as I said earlier, with no one in the lab and we would still get an interference pattern. The collapse is due to physical interactions between particles, not because of us directly influencing it with our consciousness.
 
Thanks Traveller, yes indeed I understand there was an interaction of some kind, but I'm interested to know how exactly the experiment was affected and why this phenomena occurs, or is it just a case of 'we affected it' and it is left at that?
 
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