The Observer vs. Measurement debate finally solved thanks to Wigner

You often hear this debate about the role of the observer in Quantum Mechanics. How you view this role is usually dictates the interpretation you prefer. If it's Copenhagen, then the observer is more robust and plays a crucial role in wave function collapse. If it's Many Worlds, then the observer is no different than a rock as Sean Carroll says and there's no wave function collapse. I think the recent Wigner's Friend experiment clarified the difference between observer and measurement.

Here's the experiment:

Experimental test of local observer independence

The scientific method relies on facts, established through repeated measurements and agreed upon universally, independently of who observed them. In quantum mechanics the objectivity of observations is not so clear, most markedly exposed in Wigner’s eponymous thought experiment where two observers can experience seemingly different realities. The question whether the observers’ narratives can be reconciled has only recently been made accessible to empirical investigation, through recent no-go theorems that construct an extended Wigner’s friend scenario with four observers. In a state-of-the-art six-photon experiment, we realize this extended Wigner’s friend scenario, experimentally violating the associated Bell-type inequality by five standard deviations. If one holds fast to the assumptions of locality and free choice, this result implies that quantum theory should be interpreted in an observer-dependent way.

advances.sciencemag.org...

This is important when looking at the role of measurement vs. the role of the observer. If you have a measurement, it looks like this:

|↑⟩⟹(|→⟩+|←⟩)/2

If you add in an observer, it looks like this:

|↑⟩|obs⟩⟹(|→⟩+|←⟩)|obs⟩/2

The observer can tell whether you're in state |→⟩ or |←⟩ a measurement can't.

Take a measuring device in the double slit experiment. It doesn't know what state it's in. It has stored information about which slit the particle went through but it takes a conscious observer to know the difference between |→⟩ or |←⟩ or which slit the particle went through or not.

People who support MWI can't say consciousness has nothing to do with QM because this experiment shows that it does. How you define consciousness is another debate but a measuring device can just store information. A brain is a measuring device that stores information but consciousness can look at that information in an abstract way. It knows we're in one measured state and not the other. It can publish papers and write books about it as well as think about what it means.

In Wigner's Friend, it shows that you can have a measurement but still have two different wave functions. Wigner's Friend knows a measurement took place. He recorded the results. Wigner outside of the lab can look at the same particle and see interference and conclude that no measurement has occurred.

When Wigner's Friend calls him and says I carried out a measurement and this is the result, then Bayesian type updating occurs for Wigner's wave function and now it's in sync with his friends. So a measurement collapses the wave function so to speak but a measurement can't tell which state it's in. Without observers to resolve this issue, you could have different measurements all over the place.

This reminds me of Wheeler drawing the universe as a Big U. At one end is the Big Bang and at the other end is Us(Consciousness). All of these measurements would evolve over billions of years until consciousness evolved. At that point, Bayesian updating would occur and one history of the universe or a singular measured history would be realized.

Measurements can't tell what state they're in. Wigner's Friend experiment shows the wave function of observers can have different outcomes until information about the measured state is shared between observers. Say you have a particle that goes through a slight and is recorded by a measuring device. How can that measuring apparatus relay to another measuring apparatus what measurement has occurred without consciousness?

Here's more from the paper:

Before we describe our experiment in which we test and indeed violate inequality (2), let us first clarify our notion of an observer. Formally, an observation is the act of extracting and storing information about an observed system. Accordingly, we define an observer as any physical system that can extract information from another system by means of some interaction, and store that information in a physical memory.

Such an observer can establish “facts”, to which we assign the value recorded in their memory. Notably, the formalism of quantum mechanics does not make a distinction between large (even conscious) and small physical systems, which is sometimes referred to as universality. Hence, our definition covers human observers, as well as more commonly used non-conscious observers such as (classical or quantum) computers and other measurement devices—even the simplest possible ones, as long as they satisfy the above requirements. We note that the no-go theorem formulated in [5] requires observers to be “agents”, who “use” quantum theory to make predictions based on the measurement outcomes. In contrast, for the no-go theorem we tested here [4] it is sufficient that they perform a measurement and record the outcome. The enhanced capabilities required of agents were recently discussed in [13].

arxiv.org...

This goes to my point about human observers.

The human brain can extract information about a system and store it in it's memory but the difference is, we can look at that stored information in abstract ways. We can relay the outcomes of measurements to other observers and we update their wave function. Without consciousness, how can this information be transmitted to different observers? Without this Bayesian updating, two observers can measure different outcomes for the same event.

originally posted by: neoholographic
This reminds me of Wheeler drawing the universe as a Big U. At one end is the Big Bang and at the other end is Us(Consciousness). All of these measurements would evolve over billions of years until consciousness evolved. At that point, Bayesian updating would occur and one history of the universe or a singular measured history would be realized.

Woah man. Just had a mini 2001 space odyssey moment there..

Wheeler's delayed choice experiment proved the same conclusion. In Wheeler's experiment, the particle/wave is measured after the slit, which causes it to retrograde back to the slit and makes a decision. It's as if it goes back in time and changes to a particle due to the observer's measurement. It is phenomenal. It also insists that our observation is the focal point of time.

The physical world is attentive to consciousness. Theories that don't involve a primordial consciousness as the source and creator cannot be taken seriously anymore. Because physical systems and matter require consciousness to exist, consciousness could not have been created by these systems. To say Matter created consciousness is like saying shadows created the light.

originally posted by: neoholographic
People who support MWI can't say consciousness has nothing to do with QM because this experiment shows that it does.

Here's more from the paper:

"Hence, our definition covers human observers, as well as more commonly used non-conscious observers such as (classical or quantum) computers and other measurement devices—even the simplest possible ones, as long as they satisfy the above requirements."

It seems to me like your own quote from the paper contradicts your assertion about consciousness, since they specify things like non-conscious quantum computers as observers, so I don't see how this paper shows anything about consciousness like you claim.

This is a tactic you often employ, where you cite some paper, and claim it supports something you'd like to believe, and then we read the paper and find out that it doesn't support your claim at all. The authors of the paper say consciousness isn't relevant to their definition of an observer, so it doesn't matter whether the observer has consciousness or not, human or non-conscious quantum computer can both serve as observers according to the authors. I don't see where they attribute anything special to the conscious observer (human) over a non-conscious observer.

If a quantum system was spread out sprawling for miles like a power grid and you had a detector that wasn't limited like a multi phase motor that requires 60 Hz there would be all kinds of induced harmonics. You might be able to collect these harmonic signals sort and address CC with precision because you had a more sensitive detector (finer observation).

Quantum world is just too small and there might be a fundamental resonance limit that makes quantum signals more difficult to address.

I observe things like a cat so that means I can bend everything to my reality....or basically the reality our two cats approve of.

a reply to: rickymouse

If you don't know its a superposition you won't know what it is.
There are probably classified super positions that keep things from going booom that would explain quantum reality.

originally posted by: Arbitrageur
It seems to me like your own quote from the paper contradicts your assertion about consciousness, since they specify things like non-conscious quantum computers as observers, so I don't see how this paper shows anything about consciousness like you claim.

Quantum computers are extensions of us the observer. The variable that determines whether or not the photon behaves like a wave or a particle is whether or not we, the conscious beings, wish to have it measured. Wheeler's delayed choice demonstrated this, because if it were the simply the machine causing interference, then the retrograde collapse of the wave function would not occur after the passage of the slit.

You have to be stubbornly materialistic to ignore the obvious necessity of the conscious faculty in the wave function collapse.

...and just like that, science has now returned to philosophy.

When reading about the Wigner's Friend experiment, I can't help but think of the Universe as one big computer (the server). All observers are like virtual machine clients running on the server, and forming a client-server relationship. When an experiment is done without an observer, it takes place server-side only. All observations take place client-side.

I honestly wouldn't be surprised if it works somewhat like multiplayer video game servers that processes physics on the server-side so hackers can't manipulate physics in their client-side and have that reflect on the server and all observers. A lot of designs will process physics on both the server and client, and if the client gets out of sync with the server, or does something against the written laws of physics, the server can error correct the client back into place... but I digress.

Physical matter is like the Universal server's storage drive (array of hard drives), but its also doubles as short-term memory (RAM), and the medium for internal network communication (network adapter). All clients have access to this Universal storage, meaning, everyone can see the Sun, Moon, stars and stone megaliths that have yet to be erased from storage. Also, clients have their own local memory allocated to them by the server which nobody else has access to. Local memory often contains small copies of the server's memory for local processing and cache.

When you understand the many different ways a computer system allocates and utilizes memory, things start to make sense. In software for example, before you execute a function (experiment) that you expect a result from, you have to allocate a position and size in memory to store the result. So if you expect a 0 or 1 bit from the function, you allocate 1 bit of memory at some position. Since you don't have the result yet, the value starts out as null. It can be both 1 or 0 until you get the result, almost like a "superposition" in memory if you will.

Before Wigner and his friend do the experiment, they have already allocated memory for the result in their local memory, a superposition / waveform. When the experiment is complete, and Wigner's friend reads the results from the server, the result is saved into local memory which "collapses the waveform". Since Wigner still doesn't have the result, his local memory is still is in superposition. It's not until Wigner's friend communicates the result to Wigner that his memory now matches that of the server and his friend.

So now three copies of the experiment's result are in memory. One in server's memory, one in Wigner's memory, and one in Wigner's friend's memory. This is inefficient in most cases, and can result in one or more clients having the wrong value in their memory. To make it more efficient, software will sometimes store a single value in memory and only share a reference to the position of that value to everyone that wants access to it. This removes the chance of each having different results in their memory because they all read from the same position in memory now.

...or maybe I am just too imaginative here. Buffer overflow!

Question: What happens if Wigner's friend lies to Wigner? What would Wigner see?

The dancer is spinning on her right leg:



Or is she is spinning on her left leg?

Is she spinning clockwise or anti-clockwise?

Two results of the same measurement?



Oh... symmetry...

a reply to: neoholographic

From the paper you linked, but didn't bother to read:

. Eugene Wigner,
for example, argued that the disagreement with his hypothetical friend could not arise due to a supposed impossibility for conscious observers to be in a superposition
state [2]. However, the lack of objectivity revealed by a
Bell-Wigner test does not arise in anyone’s consciousness,
but between the recorded facts.Since quantum theory
does not distinguish between information recorded in a
microscopic system (such as our photonic memory) and
in a macroscopic system the conclusions are the same for
both: the measurement records are in conflict regardless of the size or complexity of the observer that records
them.Implementing the experiment with more complex
observers would not necessarily lead to new insights into
the specific issue of observer-independence in quantum
theory. It would however serve to show that quantum
mechanics still holds at larger scales, ruling out alternative (collapse) models [20]. However, this is not the point
of a Bell-Wigner test—less demanding experiments could show that.

Question: Have you EVER read a paper in its entirety without a bias? Do you understand what inductive reasoning is and how to use it PROPERLY? Do you have a clue - about anything? Guilty on three counts.

The link below might help, although I have my doubts.

Inductive reasoning

Inductive reasoning is the opposite of deductive reasoning. Inductive reasoning makes broad generalizations from specific observations. Basically, there is data, then conclusions are drawn from the data. This is called inductive logic, according to Utah State University.

"In inductive inference, we go from the specific to the general. We make many observations, discern a pattern, make a generalization, and infer an explanation or a theory," Wassertheil-Smoller told Live Science. "In science, there is a constant interplay between inductive inference (based on observations) and deductive inference (based on theory), until we get closer and closer to the 'truth,' which we can only approach but not ascertain with complete certainty."

An example of inductive logic is, "The coin I pulled from the bag is a penny. That coin is a penny. A third coin from the bag is a penny. Therefore, all the coins in the bag are pennies."

Even if all of the premises are true in a statement, inductive reasoning allows for the conclusion to be false. Here's an example: "Harold is a grandfather. Harold is bald. Therefore, all grandfathers are bald." The conclusion does not follow logically from the statements.

Inductive reasoning has its place in the scientific method. Scientists use it to form hypotheses and theories. Deductive reasoning allows them to apply the theories to specific situations.

www.livescience.com...

a reply to: cooperton

Would you please provide a citation with the mathematics that confirms your opinion? If a quantum computer is an extension of a human, then so is my PC, my iPhone, iPad and the original sundial.

Please return to the "other" board where you rightfully are a placeholder.

originally posted by: Arbitrageur

originally posted by: neoholographic
People who support MWI can't say consciousness has nothing to do with QM because this experiment shows that it does.

Here's more from the paper:

"Hence, our definition covers human observers, as well as more commonly used non-conscious observers such as (classical or quantum) computers and other measurement devices—even the simplest possible ones, as long as they satisfy the above requirements."

It seems to me like your own quote from the paper contradicts your assertion about consciousness, since they specify things like non-conscious quantum computers as observers, so I don't see how this paper shows anything about consciousness like you claim.

This is a tactic you often employ, where you cite some paper, and claim it supports something you'd like to believe, and then we read the paper and find out that it doesn't support your claim at all. The authors of the paper say consciousness isn't relevant to their definition of an observer, so it doesn't matter whether the observer has consciousness or not, human or non-conscious quantum computer can both serve as observers according to the authors. I don't see where they attribute anything special to the conscious observer (human) over a non-conscious observer.

It could be argued that it is consciousness that programmed the computers to observe thereby transferring a conscience motive for the observation, hence the similarities in the results.

a reply to: highvein

originally posted by: cooperton

originally posted by: Arbitrageur
It seems to me like your own quote from the paper contradicts your assertion about consciousness, since they specify things like non-conscious quantum computers as observers, so I don't see how this paper shows anything about consciousness like you claim.

Quantum computers are extensions of us the observer. The variable that determines whether or not the photon behaves like a wave or a particle is whether or not we, the conscious beings, wish to have it measured. Wheeler's delayed choice demonstrated this, because if it were the simply the machine causing interference, then the retrograde collapse of the wave function would not occur after the passage of the slit.

You have to be stubbornly materialistic to ignore the obvious necessity of the conscious faculty in the wave function collapse.

OK we made the quantum computers so maybe there's a weak argument consciousness has something to do with them, but there can't be any such suggestion about other non-conscious observers that also meet the authors definition of an observer in the paper:

"we define an observer as any physical system that can extract information from another system by means of some interaction, and store that information in a physical memory."

So, two billion years ago some rocks observed and stored in memory a record of a natural nuclear fission reactor. As far as we know no conscious beings existed on Earth at the time, so consciousness has nothing to do with that observer:

Nature's Nuclear Reactors: The 2-Billion-Year-Old Natural Fission Reactors in Gabon, Western Africa

at the Gabon reactors many of the radioactive products of the nuclear fission have been safely contained for two billion years, providing evidence that long-term geologic storage of nuclear waste is feasible.

Unlike quantum computers, humans and consciousness had nothing to do with that; the observations were already made by the rocks and stored in the "memory" (geologic record) of the rocks. Those observations the rocks made didn't involve any consciousness.

a reply to: neoholographic

Perhaps the photons have a desire to be observed and it turns them on. I don't know.

a reply to: Arbitrageur

but there can't be any such suggestion about other non-conscious observers that also meet the authors definition of an observer in the paper:

Why? A conscious effort was put into the programming to do the observations. A transference of that consciousness when the program runs.

So, two billion years ago some rocks observed and stored in memory a record of a natural nuclear fission reactor. As far as we know no conscious beings existed on Earth at the time, so consciousness has nothing to do with that observer:

Not the rocks, but the photons that were around observed it. Photons can hold information.

a reply to: Phantom423

Would you please provide a citation with the mathematics that confirms your opinion? If a quantum computer is an extension of a human, then so is my PC, my iPhone, iPad and the original sundial.

They are an extension of your consciousness. You are using them to extend a conscious thought. A transference of consciousness.

originally posted by: highvein
a reply to: Phantom423

Would you please provide a citation with the mathematics that confirms your opinion? If a quantum computer is an extension of a human, then so is my PC, my iPhone, iPad and the original sundial.

They are an extension of your consciousness. You are using them to extend a conscious thought. A transference of consciousness.

Nice. How about a citation of supporting experimental data? I always wanted to know what absolute zero felt like. Maybe you've got the key!

Can anyone explain what the actual experiment is and what the results are?

I'm too dumb to understand what Im reading but not dumb enough to think its magic.

a reply to: Phantom423

Nice. How about a citation of supporting experimental data?

You want a citation of supporting experimental data about you consciously sending a signal from your electronic device in order to send that information to another conscience? I think your actions to consciously send that signal should be proof enough.

I always wanted to know what absolute zero felt like. Maybe you've got the key!

Absolute Zero doesn't feel like anything. Your dead by then.

originally posted by: Arbitrageur

originally posted by: neoholographic
People who support MWI can't say consciousness has nothing to do with QM because this experiment shows that it does.

Here's more from the paper:

"Hence, our definition covers human observers, as well as more commonly used non-conscious observers such as (classical or quantum) computers and other measurement devices—even the simplest possible ones, as long as they satisfy the above requirements."

It seems to me like your own quote from the paper contradicts your assertion about consciousness, since they specify things like non-conscious quantum computers as observers, so I don't see how this paper shows anything about consciousness like you claim.

This is a tactic you often employ, where you cite some paper, and claim it supports something you'd like to believe, and then we read the paper and find out that it doesn't support your claim at all. The authors of the paper say consciousness isn't relevant to their definition of an observer, so it doesn't matter whether the observer has consciousness or not, human or non-conscious quantum computer can both serve as observers according to the authors. I don't see where they attribute anything special to the conscious observer (human) over a non-conscious observer.

Sadly, you fail to see something right in front of your face. You quoted:

non-conscious observers such as (classical or quantum) computers and other measurement devices—even the simplest possible ones

These non conscious observers are mostly designed by consciousness so conscious observers can know what state we're in!!!

Let me repeat:

These non conscious observers are mostly designed by consciousness so conscious observers can know what state we're in!!!

How hard is this to understand?

If you have non conscious observers then you have measurements that can be different for the same event. The only way this is resolved is through conscious Observer A telling conscious Observer B what measurement their in and this updates conscious observer B's wave function.

This can't happen without consciousness. You will never get a single history with non conscious observers. This test clearly shows this.

Without Conscious Observers saying we're in this state or that state and then relaying that outcome to other conscious Observers, you will just have different measurements and not a single history.