Is Quantum Mechanics Affected By Consciousness?
The difficulty of understanding how subjective, conscious experience may develop from physical stuff is generally understood. Generally, the matter-to-consciousness direction is the one that is emphasised. However, there is a confounding issue moving the other way. What causes awareness in relation to physical matter? What does consciousness do, in a nutshell?
When we attempt to understand the quantum realm using common sense reasoning, we find it to be challenging. Additionally,
we lack a solid explanation upon which we may assert, "This is why it is happening!
This is the main reason why there are many original hypotheses describing various quantum mechanical phenomena. Some of these new hypotheses are fairly daring and even incorporate mysticism to some extent. For instance, we are aware that the measurement itself modifies the behaviour of the entangled pair of photons if we observe one photon. It seems as though our knowledge and consciousness have an impact on what is going on in the world.
Does consciousness produce reality? Can consciousness be explained by quantum physics?
Because of this, there is a particularly pervasive idea that awareness can directly affect quantum systems and hence affect reality as well.
For example, one of the most illogical events ever seen can simply be categorised as the quantum eraser experiment.
The quantum eraser experiment: A visual impression
Interferometers are used in this experiment to show some of the main ideas of quantum mechanics from a technical standpoint. A single photon can be shown to pass through two slits simultaneously using the identical double-slit arrangement, but this time detectors are employed to track which slit the photon passes through.
The quantum eraser experiment shows, in a concrete way, how quantum physics "mixes" the past and the future. The behaviour of the second photon is altered when one of the two entangled photons is measured by a detector, even if only for the purpose of tracking its route. Furthermore, if you artificially extend the photon's propagation path after its "cousin" photon hits the screen and measure it afterward, the outcome will remain the same: the photon measured in the future will influence the behaviour of the "cousin" photon in the past.
Light particles do not appear to 'know' if they are being observed, as far as we can tell.
Physicalism is a common viewpoint in philosophy of mind. According to physicalists, the mind is merely the brain. Thus, a specific experience, such as an itch or a visual perception of red, would be nothing more than electrochemical processes taking place in the brain. Dualism is a less popular viewpoint. According to dualists, the mind and the brain are separate. According to this theory, conscious experience is distinct from the brain functions that go along with it and is therefore non-physical.
Physicalists assert that contemporary science has disproved dualism. They contend that all of the available data demonstrates that the physical universe is a causally closed system, negating the possibility of non-physical minds having any influence. Jones, for instance, goes to the refrigerator because he has a conscious need for beer. A significant number of particles are set in motion as Jones approaches the refrigerator. If dualism were genuine, something non-physical would have moved the particles. However, the equations controlling particle motion in the physical sciences do not allow for such external influences to move particles. Dualism is therefore fallacious. The causal closure argument refers to this.
A 1932 book by John von Neumann contains the standard explanation of quantum mechanics. It is perplexing because, when taken literally, it postulates two fundamental natural rules that seem to be at odds with one another. First, there is the law that the Schrodinger equation explains. This law is deterministic; using the Schrodinger equation, one can determine a system's precise physical state (i.e., wavefunction) later on in relation to that system's physical state earlier. The collapse postulate's description of the law is the second. The collapse postulate only gives probabilities to the potential future states of a physical system given its existing state, making this law probabilistic rather than deterministic. (These probabilities depict the real-world randomness that exists.)
When examining the quantum systems' physical states, this issue is even worse. Not only does measurement cause the measured system to evolve inexplicably, but it also seems to alter the system's basic character. Because particles are not often described in quantum physics as being situated at specific positions in space, Instead, it enables simultaneous localization of a single particle at many sites. In these circumstances, the particle is said to be "in a superposition of several places." When the particle's location is measured, its superposition is said to "collapse," causing the particle to hop at random to a single point. The infamous double-slit experiment serves as an illustration for this.
The Double-Slit Experiment
In this experiment, a fluorescent screen is the target of one electron fired at a time. We can determine the electron's location by measuring the brightness of the place on the screen where it makes contact with the screen. In the actual experiment, a wall with only two tiny openings blocks the way to the screen. The pattern of spots that develops on the fluorescent screen after several electrons are discharged in the direction of the wall does not, contrary to what one might anticipate, consist of two bands of spots corresponding to the two slits. It is actually an interference pattern (roughly, many bands of spots, making the screen look like the body of a zebra).
An example may be useful in understanding the traditional explanation for these findings. Imagine doing this experiment in some water. Instead of shooting particles at the screen, we drop a pebble that causes a wave of water to be sent in that direction. What happens when the wave with the two slits strikes the wall? While some of it is redirected backwards, each slice creates two additional ripples that move in the direction of the screen. Before touching the screen, these two new ripples collided as they fanned out. The pattern on the screen will be impacted by the collision of the ripples if the screen is built to measure the strength of the water waves. This is similar to how the interference pattern is explained by conventional wisdom.
Think about the path an electron takes. It is fired at the wall. The Schrodinger equation predicts that it will fan out (like a ripple). The electron is thus in a superposition of passing through both slits, with a component coming from one slit and a component coming from the other slit. Then, these two elements spread out and engage in interaction. The electron then hits many points on the screen in a superposition. These many places fit into an interference pattern.
A measurement of the location of one electron is represented by a spot lighting up on the screen. The Schrodinger equation is replaced by the collapse assumption during measurement. As a result, the spread of superpositions comes to an end and the electron randomly collapses to one place on the screen, leaving only that one spot visible to us. Thus, the interference pattern cannot be produced by one electron. However, as we pass more electrons through, a pattern of interference develops. Now that there are more measurement devices at the slits, each electron only passes through one slit because it collapses too early. There will be no interference and thus no interference pattern if the electrons are not in superpositions of passing through both slits.
Therefore, it appears that measurement has two effects: first, it modifies the very nature of physical systems by transforming their 'wave-like' superpositions into known 'particle-like' states, and second, it results in genuinely random behaviour in the entity being measured (since the wave-to-particle transition is random).
The theory that consciousness
causes quantum collapse
Why does this matter? For one thing, what exactly constitutes a measurement does not seem like a strong candidate for a fundamental physical process. Many have therefore attempted to completely ignore the collapse postulate and instead allow superpositions to propagate in accordance with the Schrodinger equation. Accordingly, the screen enters a superposition of detecting a single electron in many locations after just one electron is pushed through. The human viewer then looks at the screen and experiences a spot at one point, a spot at another, and so on in a superposition. The human observer breaking into several viewers, each of whom sees a distinct spot, is how supporters of this viewpoint read this. Each divides in response to the environment, which also divides as a result. This is the so-called many-worlds interpretation of quantum mechanics, which has gained a lot of physicists' attention. This is a radical hypothesis, albeit it fits with physicalism. Any solution to the measurement problem would, however, inevitably have profound effects.
The collapse premise is maintained but revised in another school of thought. The standard interpretation of quantum theory now provides the most potent method for anticipating experimental outcomes in the annals of physics. Therefore, we must take care to preserve its predictive power no matter how we alter it. That entails making sure collapses occur when they must (such as before an observer acquires a visual impression of the screen) and avoid occurring when they ought not to (e.g. unmeasured electrons do not typically collapse during their journeys through the double-slit apparatus).
Retaining the collapse postulate while changing "measuring causes collapse" to "aware observation causes collapse" is one method to achieve this. Several physicists put up this hypothesis in the early days of quantum mechanics. "A measurement is achieved only after the position of the pointer [or the spot on the luminous screen] has been noticed," Fritz London and Edmond Bauer noted in 1939. [...] We witness the crucial part played in this transformation by the observer's consciousness. The Nobel Laureate Eugene Wigner was influenced by London and Bauer when he said in 1961 that "the idea of consciousness came to the fore again when the province of physical theory was extended to embrace microscopic events, through the invention of quantum mechanics: Without mentioning consciousness, it was impossible to establish the rules of quantum physics consistently.
This fundamental idea, meanwhile, was never completely developed. Instead, it was diverted onto mystical, scientifically useless pathways, and is today generally disregarded by physicists. I believe there are three key reasons physicists reject it:
Problem 1
The term "consciousness" has no clear definition. Since "awareness" is as vaguely defined as "measurement," the hypothesis is unable to resolve the measurement issue. As a result, it is unable to provide any fresh testable hypotheses.
Problem 2
The way a person is described physically shouldn't depend on who is looking at it. The fact that observers are just relatively recent additions to the universe and that it took billions of years for the first animal to appear on Earth makes this especially true. This claim does not meet that criteria.
Obstacle 3
Physicalism, the dominant philosophical tenet, is incompatible with the hypothesis. In its place, it necessitates some kind of antiquated, debunked mind-body dualism.
These objections are valid. But I think these can be addressed given recent advances in neuroscience.
Responses To The Objections
According to recent neuroscience studies, brain areas with coordinated neuronal activity are associated with awareness. Contrast the cerebellum with the brain. It can be removed from the body without doing much harm to one's stream of consciousness since the cerebellum, despite having a far higher density of neurons, does not strongly correlate with consciousness. Despite having only a small number of neurons, awareness has a strong correlation with the cerebrum. What is the primary distinction? However, when one cerebellar subregion is probed, the effects on the other subregions are minimal. Contrarily, if you investigate one part of the cerebrum, it will interfere with what is happening in other parts of the cerebrum. Some neuroscientists think that defining the physical correlates of consciousness will need a mathematically exact measurement of this kind of causal interconnection. Such a formula would allow us to determine whether and to what extent any potential physical system is conscious.
Objections 1 - Response:
This objection requires the hypothesis to provide testable predictions. Our "awareness causes collapse" hypothesis changes when IIT is included to "integrated information causes collapse" (measured as Φ ). Importantly, Φ is an exact mathematical quantity that can be determined for any conceivable physical system. As a result, our hypothesis now yields clear-cut experimental predictions.
Think about the double-slit experiment once more. When shooting complicated molecules like Buckminsterfullerene-each made up of sixty carbon atoms-through the slits, this experiment has shown interference patterns. The tests being conducted by physicists involve firing increasingly sophisticated systems through the slits. The experiment might eventually be repeated twice using two separate groups of nanocomputers. Members in one group have high Φ. The other group's (the control group's) members have minimal or no Φ. If the latter group is the only one to produce an interference pattern, the consciousness causes collapse hypothesis will have been experimentally verified (assuming IIT is true).
Answer to Second Objection:
In order to satisfy the second objection, there must be only one objective account of reality, not a different (but equally valid) description for each observer. The hypothesis just suggests that because of the existence of Φ, the description of reality may occasionally vary over time, hence this challenge is overcome. This evolution of the description over time is impartial because it should be recognised by all observers.
We want physics to explain the early universe before there were any observers, which is one reason why we want physical descriptions to not depend on observers. It may appear that our theory states that the universe abruptly collapsed when conscious life first appeared on Earth. There would be a number of issues with this. Fortunately, this does not imply anything given IIT. IIT disagrees with the anthropocentric notion that only people and things that resemble humans possess consciousness. There are minute levels of Φ in every atom and molecule. IIT implies that they have a minimal level of consciousness, assuming they are not parts of systems with higher levels of φ. Therefore, it is reasonable to assume that quantum collapses occurred pretty early in the universe's existence, but at a lower intensity and frequency. (A fully consistent theory will necessitate that the strength and frequency of collapse be proportional to Φ , though the specifics are outside the purview of this paper.)
Response To Problem 3:
Given that there are both physicalist and dualist interpretations of our theory, there are two plausible solutions to the criticism that it is not physicalist. The physicalist demand is immediately satisfied by the physicalist interpretation! The physicalist approach makes no mention of awareness. Instead, collapse is brought on by the physical counterpart of consciousness (Φ). According to the rules, systems with enough Φ are what cause quantum collapse. Physicalism is congruent with this.
The physicalist view, though, has a strange quality. , a high-level feature of numerous causally related constituents, is not a fundamental property of matter. It seems strange to formulate a fundamental natural law in terms of a non-basic high-level feature. Even worse, why is consciousness the correlate of the high-level feature that causes collapse? According to the physicalist perspective, this appears to be an odd coincidence. Such considerations nudge us in the direction of the dualist theory, which holds that consciousness is essential.
According to the dualist interpretation, awareness-not collapse-causes collapse, and consciousness itself is merely a measure of consciousness. It will be necessary for this interpretation to reject objection 3 in some way, maybe by demonstrating that it is false. And there are grounds for believing it does. Due to dualism's dependence on an idea that is widely regarded as a discredited remnant of Descartes' antiquated 17th Century theories, many physicists reject the dualist interpretation. The following is a formulation of the alleged discrediting argument for dualism:
(1) Physical causes can be used to account for everything that occurs in the physical world.
(2) As a result, nothing that occurs in the physical world can be a result of non-physical consciousness.
Since one's thoughts do not cause one's words to be said or one's anguish to cause one to scream out, this either leads us to physicalism or the unpleasant conclusion that the mind has no influence on the physical world. This is considered by many philosophers to be a strong evidence against dualism.
Philosophers contend that (1) is supported by the idea that causal laws in physical theories never need to invoke awareness. But what natural events result in collapse? Since we are unsure, (2) is not truly supported. Therefore, there is an odd phenomenon whereby physicists reject the dualist interpretation by appealing to philosophy and then go on to develop physicalist answers to the measurement problem (such as the many-worlds interpretation), while philosophers reject dualism by appealing to such physical theories (and specifically, the fact that the laws of those theories don't mention consciousness). If that's what the physicalism defence boils down to, it's a vicious circle.