Wave function collapse demystified

THE QUANTUM MESS: ARE OBSERVERS NECESSARY? The question quantum physicists dare not ask: what if there are no observers?

In my section on Schrodinger's cat, I noted how, according to some, it takes an observer to determine the fate of the animal, and until there is such an observation, the cat is both alive and dead at the same time. This thought experiment was an analogy for something in the quantum world that some outcome can have equal but mutually exclusive possibilities (i.e. - an outcome where you can have both being and not being simultaneously), at least until a measurement/observation is made and things fall into place as either being or not being. [There's an interesting variation on that cat thought experiment. Say the cat-in-the-box is in a room and I'm also in the room, and after one hour I peek in the box and determine the aliveness or deadness of the animal. But, say you are outside the room when I do that. As far as you are concerned, the cat's wave function hasn't collapsed and the cat is still dead-alive. So you have got to look too! But then what about a third party in another room in the house, then the neighbour next door, and hence other residents of the town, then state, hence country and then the entire world. Of course the cat would be in a limbo dead-alive state to extraterrestrials on another planet until they looked, and so on. In fact, taken to a logical extreme, nothing has reality until the entire Universe observes, which is again (IMHO), absurd seeing as how it could take billions of years for that cat observation to reach the farthest regions of the cosmos!]

In a similar way, there are those who argue that nothing is real unless that something is observed. For example, the Moon dissolves into quantum uncertainty, the Moon is and is not, if nobody is actually looking at the Moon! As soon as someone looks at the Moon, it solidifies back into physical reality. The absurdity (again IMHO) of that is that if the Moon faded away into quantum uncertainty that would play havoc with the tides and be noticed. Perhaps observing the tides is sufficient to give the Moon reality without actually observing the Moon!

Extrapolating, there are those who believe and would argue that the entire Universe exists (has reality) only because there are observers to observe or measure it. Clearly (unless you count God [if He/She/It exists at all] as an observer from Day One), the Universe was in a lifeless state and evolved in a lifeless state from Day One through several billions of years at least. That is, there were no observers at all. The Universe had to exist in a pre-observers stage in order to evolve the complexity required to produce observers. An early Universe consisting of only hydrogen, helium and radiation doesn't hack it as far as being a suitable environment for observers. So, in terms of this chicken-or-the-egg question, the Universe-or-the-observer question, the answer must clearly come down on the side of the Universe. The Universe can exist either with or without observers; observers exist only because there is a Universe.

Lastly, no one has defined exactly what constitutes an observer. What about an inorganic things like a Geiger counter or thermometer? Can it be anything that's alive like a plant or bacteria, or does it have to have a sophisticated nervous system (higher sensory capacity)? Maybe there has to be a complex brain within. Maybe an observer is only a bona-fide observer if it has intelligence, but what degree of intelligence? A one day old baby or someone who is brain damaged might look in the box and see Schrodinger's cat but has no capacity to understand what they are seeing. What about an artificial intelligence?

I conclude (or believe) that observers and measurements have bugger-all to do with reality, existence and how things work on either a macro or micro scale. The proof of that pudding, if any were necessary, is that radioactive substances decay with a measured half-life. The entire science of radioactive dating depends on this. And radioactive elements decay whether or not observers are present - they have; they do; they will.

Time entanglement thought experiments that link microscopic possibilities to a macroscopic event can be quite complex. Very often there is a confusion of microscopic possibilities or phase coherence and macroscopic realities. The cat thought experiment does show some short period of entanglement, but the cat's state largely represents a simple lack of knowledge about a realized event.

Observers are a mere convenient representation of an action, but actions happen and quantum states dephase in the universe all of the time without any observer present.

The paradox presumes first of all that quantum events are not realized until we observe them, which is not really quite true. The cat's state is then just like a quantum state and also not realized until we observe the cat. The paradox further presumes that the particle and cat states remain coherent with each other until we open the box. When we open the box and observe the cat's state, then and only then is its true state revealed. Thus the paradox: How can the cat have been both alive and dead?

Unfortunately, the Schrödinger's cat thought experiment thoroughly confuses entanglement of two coherent quantum possibilities, the particle states and the cat's fate, with the macroscopic and mostly incoherent reality of the cat. Although all actions are quantum events and all action therefore involves entanglement, after some very brief period after the quantum event, the cat is either alive or dead. That is a knowable state and there is not an entanglement of its possibilities.

In fact, the particle's state is also mostly knowable as well and it does not remain entangled for very long either. Quantum states are coherent with each other typically, but not always, a very brief period. The particle hits other particles and they hit back and soon, these subsequent actions dephase the quantum state.

The key question to answer is that: Once we observe the cat, can we then conclude that it had been in a dead state since the quantum event occurred? Of course. This information is therefore knowable and so our Cartesian local causality is fulfilled as far as the cat is concerned. There is only a very short period of entanglement of the cat with the quantum event and only during that very brief time is there entanglement.

Likewise, even the quantum particle is likely to dephase rather quickly and so we conclude the reality of the quantum uncertainty for the same reason. The particle states are subject to entanglement only during a short period. Once again, a soon as an event is knowable, it is no longer entangled and we just lack that knowledge of the event.

John,

you wrote "Extrapolating, there are those who believe and would argue that the entire Universe exists (has reality) only because there are observers to observe or measure it." Whether that point of view is correct depends upon what one is referring to when one says "the universe". If it means all that materially (essentially , fundamentally) exists, the Object universe, that is different from the visible universe, that I call the Image universe. The Image universe is a product of the receipt and processing of EM data giving an output that depicts what was together with temporal spread, and distortion due to such phenomena as gravitational lensing. It is a fabrication that relies upon observation, detection equipment, artistic interpretation of measurements and final observer visual senses. The beautifully coloured renderings of distant galactic dust clouds do not exist out there in space as they are seen. Material change will have occurred over the light years it has taken the data to reach the Earth. Image reality requires observers. Object reality, actualised objects consisting of atoms and fermion particles do not.

What happens upon observation is consideration of the object changes from all possible states in abstract phase space, that is not any singular iteration of the object universe, to consideration of the singular image reality produced from received EM data, when the observer looks or the measurement is taken. These are very different concepts even if they are given the same name such as the cat.

Inorganic devices and sensitive materials can be regarded as observers because they receive em data and convert it into an image reality output. Eg. EM data in ,ink on paper or screen image output.

Georgina,

That phrase "image reality" is a new one that I've never come across before. I assume 'image' refers to not only sight but sound, taste, smell and touch as well, since a blind person can't image you or any part of the Universe.

Actually I quite like the idea of Panpsychism which basically postulates that everything is an observer, even electrons and positrons; rocks and minerals; a can of this and a can of that, you name it, it's an observer. All things have consciousness and awareness of other things even if they don't have anything akin to eyesight. That makes a weird sort of sense since everything material must have gravity and if you have gravity you must 'observe' everything else that has gravity. So my two cats 'observe' each other because each has a mass and therefore gravity and thus attract each other even if they are in separate rooms and out of visual sight of each other. The same applies to two cans of food. You name it, it observes. Thus, the entire Universe has reality because everything is 'observing' everything else 24/7/52.

The interesting thing about that is that with everything observing everything else all the time, there can be no superposition-of-state and no probabilities and no collapse of any wave-function.

John Prytz

Mr. Agnew,

So no doubt you believe, even with qualifiers, that Schrodinger's Cat is both alive and dead at the same time (however short that interval might be) since it is entangled with that radioactive nucleus that has both decayed and not decayed at the same time (however short that interval might be). You did state that all action involves entanglement.

Here's a lesson in common sense, or more formally logic if you will - something cannot both be and not be at the same time in the same place for however briefly a time that might be. To suggest otherwise is just pure ignorance. If you make the claim to the contrary, show me the evidence that superposition-of-state and the so-called (alleged and associated) 'collapse' of the wave-function is experimentally true. You can't because when you allegedly 'collapse' the wave-function with your observation or measurement, how do you know the alleged wave-function wasn't already 'collapsed' by the time you peeked or more to the point perhaps in reality had always been in a 'collapsed' state on the logical grounds that the wave-function can't 'collapse' since there was no superposition-of-state with an associated wave-function that required 'collapsing' in the first place. The 'collapse' is pure fiction.

Further, there's no experiment that demonstrates a superposition-of-state, that something is simultaneously both in this state AND in that state at the same time and place. That's because experimental results always show that you end up with this state OR that state. Experiments designed to detect particles find particles; experiments designed to detect waves detect waves, even if the experiments are closely related, like the Double-Slit experiment and variations on that theme.

So how do I explain wave-particle duality? I explain duality via the simulation hypothesis. Simulating the anomalous results inherent in the Double-Slit experiment(s) is no big deal to a software programmer. I've consistently stated that the best evidence for the Simulated (Virtual Reality) Universe resides in quantum physics.

John Prytz

Yes, you are making progress...

"Here's a lesson in common sense, or more formally logic if you will - something cannot both be and not be at the same time in the same place for however briefly a time that might be."

Now you finally have stated the essence of entanglement and of our quantum reality and it certainly is beyond our normal experience, but still within the subroutine of our reality. There are objects that can be in two places at once as matter waves.

Evolution only gives us the ability, a common sense as you say, for predictions of common action. Microscopic matter is simply beyond our normal experience. Good luck in your journey of pure common sense.

An object, like a photon, can be in two places at the same time as coherent matter waves and that superposition can persist for the time of the universe. We do not sense single photons directly, but do have equipment and technology that can. It is from these measurements that our quantum reality has emerged.

Most action of common experience, like cats and neural impulse waves, involve very short dephasing times, but simple microscopic actions, like photon matter waves, can persist as coherent with a source for very long times. We see the coherent cosmic microwave background source some 13.8 Byrs ago, or more properly a z = 1091, and another observer in a galaxy across the universe sees the same CMB source. Our reality is entangled with that observer when we see the same actions at the CMB source.

That is simply the way our universe works, our reality, or what you would say, the master gamer messed up this subroutine somehow for our reality. You explain anything you need to explain with a master gamer, but I choose to simply explain things with the reality that simply is the way it is.

As far as superposition of matter waves and what is commonly called wave function collapse, there are confusing and often conflicting different interpretations going around like viruses. This superposition of our intuitive and mathematical languages results in quantum interference and standing waves of discourse. The funny thing is that the quantum math works fine...it is only the interpretations and superposition of languages that gets entangled.

If you stand at a node of constructive interference, you believe that reality makes sense and all objects have only a local reality associated with the norms of time and matter. If you stand in an antinode of destructive interference, all reality seems to vanish and nothing seems to make sense since all objects seem to be everywhere at the same time. At a universal antinode, all objects in the universe seem to vanish in moment of destructive interference.

But common reality is only what we sense with the norms of time and matter and so the antinodes of quantum interference are just what we imagine and calculate with our mathematics and indirectly observe. Our intuition is very good for normal predictions where the norms of time and matter dominate. Our intuition tends to fail when we measure the interference of time and matter amplitudes and it is that quantum interference that is the root of our reality...or subroutine as you say.

It would seem to me like we had a very good master gamer after all...

John,

thanks for your reply. Image reality is a description I have been using for many years and though only too familiar to long time participants on this site it is probably unfamiliar outside of this little, tolerant enclave.

Image reality is as you reason the output of processing of any kind of stimulus. What is output is a reality that differs both from the source of the stimulus and the stimulus itself. Experiences are image realities that do not exist externally to the observer. The sensations red, bitter,and melodic do not exist externally they are outputs. The stimuli being just waves of energy or chemicals that do not in themselves possess the sensations they instigate.

I would not attribute consciousness to a can of food, though it can absorb and emit EM data, it as a mere object acts as a source of data not as an observer. An observer can see the EM emitted from the can and form an image reality from it. The can does not form an output that simulates the source of the em it received, unlike for example photographic film or sound recording apparatus or organism.

The point really is that a new definite reality that didn't previously exist is generated upon the act of observation. The output of processing of the data received. Prior to that we can't know what the reality is, a falling coin is neither just heads nor just tails because what it is will depend upon how it is falling and where and when it is caught and what happens subsequently prior to looking. IE does the observer just open his hand or does he flip his closed hand onto the back of his opposite hand, then releasing the coin, before looking. When the cat is observed the image reality of a live or dead cat is generated. Prior to that only the probabilities are knowable and so the state can be imagined to be, like the falling coin, in an indefinite limbo. I think it is necessary to accept that the quantum state in phase space is not a flesh and blood organism in space but is a representation of mathematical probabilities only associated with the flesh and blood creature.

Georgina,

I've been mulling over your 'image reality' ideas. Just a few points come to immediate mind.

What happens to the state of reality if there are no observers? You'd have to expect that the vast majority of the cosmos isn't being observed by anything that we normally define as having sensory apparatus like eyeballs and consciousness.

Now you might observe X and therefore it has 'visual reality' while someone else observes Y and therefore it has 'visual reality', except you aren't in a position to observe Y and the other guy isn't in a position to observe X, so are both X and Y real or are both unreal?

Since you place the accent on the word 'visual' you'd be aware that there are lots of optical (visual) illusions. In fact there are also tactile and auditory illusions too. An example of a tactile illusion is the phantom limb experience by someone who has had some part(s) of their body amputated (or weren't born with them in the first place). So what is the state or the status of the reality of an optical illusion in your worldview?

Which brings up the thorny issue that one should beware of the nature of your reality for what you see isn't always what you get. 100% of your reality is experienced, processed, and interpreted by your brain. That's where all of your reality ultimately lies and there doesn't have to be a one-to-one correspondence between what's out there and what's between your ears. Or, as I like to phrase it, you exist inside of the universe but equally real is the fact that the universe exists inside you (or at least inside of your brain).

The upshot of all of that is that if you're interested in the nature of reality, study the neurosciences as much as you do the physical sciences.

Oh, as to that can of food, the rationale is that if you attribute awareness to the elementary particles, then anything constructed out of those particles, like a can of food, must also have awareness or a consciousness.

John Prytz

Mr. Agnew,

Thanks for your detailed reply. Mine won't be quite as long.

Firstly, I wouldn't knock common sense. It has served mankind (person-kind?) extremely well for multi-thousands of years. You no doubt apply common sense again, and again, and again as you go through your daily routines.

But even more formal than common sense is logic, the sort taught in universities. One facet of formal logic says that one object cannot be in two places at the same time. I personally adopt that point of view and unless it can be experimentally proved, not just speculated on as a matter of it appears to explain something, that something being that one fundamental object can exist at Point A AND at Point B at the same time, well till then I shall adopt a sceptical view and adopt logic as well as the associated Occam's Razor philosophy and reject the 'one object in two places' dictate.

I'm well aware that quantum maths works extremely well, even better than extremely well - near perfectly. That's resulted in the gizmo's that have been produced based on quantum mechanics now responsible for a third of the world's economy. Thus, one quantum mantra is "don't worry about what quantum mechanics means, just shut up and calculate".

Fortunately, I'm in a position, or rather so inclined, to worry about what does it all mean. The philosophy of quantum physics is far more interesting to me than creating gizmo's based on quantum mechanics.

John Prytz

It is very interesting to look at the wavefunction collapse in the context of German idealism and what German idealists call intellectual intuition (intellektuelle Anschauung). I discuss that in my paper: http://www.academia.edu/8991727/Phenomenal_World_as_an_Output_of_Cognitive_Quantum_Grid_Theory_of_Everything_using_Leibniz_Kant_and_German_Idealism

COLLAPSE OF THE WAVE-FUNCTION REVISITED

For those of you who have absolute faith that something can both be and not be at the same time and in the same place (i.e. - in a superposition-of-state), here's an ultimate test of your faith and your nerve. In the Schrodinger's Cat thought experiment, the radioactive nucleus, unobserved, had a 50/50 chance of going poof within one hour. Thus, for the duration of that hour, the radioactive nucleus had a superposition-of-state of being both decayed and not decayed. The cat, whose fate depended upon that state of affairs was therefore in a superposition-of-state of being both dead and alive at the same time. Now no doubt you would have no problem standing next to the box that contained the radioactive nucleus and the cat (as well as the other apparatus designed to make this all work). After one hour you could have a look, collapse the respective wave-functions, and either find a poofed nucleus and a dead cat or an un-poofed nucleus and an alive cat. No problem (apart from the poor puss if she's now deceased).

Now substitute the cat with a thermonuclear bomb. If you seriously have faith in the BOTH this AND that state of affairs, then you must seriously believe that a thermonuclear bomb can be both exploded and not exploded at the same time until you peek. You would be very comfortable standing next to the box that contained the radioactive nucleus and the thermonuclear bomb(as well as the other apparatus designed to make this all work), as long as you didn't peek. Of course you might not be quite so comfortable lifting the lid on the box after the one hour had expired to check on the bomb's actual status, but you could arrange for a robot as a stand-in observer after that one hour had expired. The point is, you would be 100% comfortable standing next to that box for the duration of that one hour, absolutely confident that you'd be safe, since the bomb's wave-function was intact and hadn't collapsed.

Hands up all of you who would volunteer to stand next to that box for the duration!

SUPERPOSITION-OF-STATE

Here's the fundamental question. How did the cosmos manage to strut its stuff when it was all tied up in superposition-of-state knots and there were no observers yet thought of in anyone's philosophy to collapse wave-functions?

If there were however no actual superposition-of-states prior to the origin, evolution and eventual existence of observers, enabling the cosmos to strut its stuff, why should there literally be superposition-of-states in existence post the origin, evolution and existence of observers?

And if superposition-of states are not actual or literal but just abstractions of possibilities or probabilities held in the conscious minds of potential observers, then as far as the cosmos goes - and this is what really counts - it's all irrelevant, immaterial, of no consequence and collectively a total non-event.

Actually, John I had elsewhere on this forum suggested that an autopsy to ascertain the time of death can tell us whether the cat recently died when the box was opened or had died long ago. I am with you here.

I wrote in my site detailed explanations of how I see a fundamental role of observers in wave function collapse, and big problems I see with the main other interpretations (especially Bohmian mechanics, but also many-worlds and spontaneous collapse). See also my essay in this 2015 contest : A Mind/Mathematics Dualistic Foundation of Physical Reality that includes the main points and other aspects of this interpretation.

Sorry Darius M, I could not read your paper to see how much we may agree because it is much too long. So I invite you to read my texts instead, which are much shorter.

Hello everyone! I hope that I have entered the correct forum. :-)

I am a teacher of physics by occupation. I was invited to write a script and work on the visualizations for the new popular science documentary film on the topic of Laws of Nature and whether they are changing. I wrote a draft with perhaps a few additional sentences interspersed. I would like to invite you all to view the draft and discuss it in FQXI forum (or whichever way you prefer).

You can view it here (English language, 4700 words, words not emphasized in any way):

https://animagnetic.wordpress.com/2015/02/01/are-laws-of-nature-about-sentience/

Brief background

The producer set the topic and the goals: 1. to research scientifically and elaborate 2. to make it accessible for wide audience 3. to go beyond the existing paradigms or to introduce something entertaining (for short). A documentary may contain at most 7000 words. The most likely form of documentary contains 6000 words. Less is better, but some words may become images, so additional descriptions may apply.

Following a long research, I established that the story of fundamental forces still represents the key topic in physics as this describes the laws of nature. In math, the key area is dynamics. Chaos theory and information theory bring new insights, and the quantum biology is the likely next revolutionary step in science.

I touch the topic of quantum biology slightly and suggest my vision for the quantum wave collapse and quantum field, which is why I was drawn towards this particular forum.

I would appreciate any discussion, criticism, or suggestions towards further simplifications for the audience.