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by Robert Lea
from
PopularMechanics Website
an experimental physicist, and a professor of philosophy to weigh in...
Yet, in the newly-created fields of quantum physics and cognitive science, difficult and troubling mysteries still linger, and occasionally entwine.
Why do quantum
states suddenly resolve when they're measured, making it at least
superficially appear that
observation by a conscious mind has the capacity to change the
physical world? What does that tell us about consciousness?
Stop us if you've heard this one before:
Early quantum physicists noticed through the double-slit experiment that the act of attempting to measure photons as they pass through wavelength-sized slits to a detection screen on the other side changed their behavior.
This measurement attempt caused wave-like behavior to be destroyed, forcing light to behave more like a particle.
While this experiment answered the question "is light a wave or a particle?" - it's neither, with properties of both, depending on the circumstance - it left behind a more troubling question in its wake.
What if the act of observation with the human mind is actually causing the world to manifest changes , albeit on an incomprehensibly small scale?
Renowned and reputable scientists such as Eugene Wigner, John Bell, and later Roger Penrose, began to consider the idea that consciousness could be a quantum phenomenon.
Eventually, so did researchers in cognitive science (the scientific study of the mind and its processes), but for different reasons.
Ulf Danielsson, an author and a professor of theoretical physics at Uppsala University in Sweden, believes one of the reasons for the association between quantum physics and consciousness - at least from the perspective of cognitive science - is the fact that processes on a quantum level are completely random.
This is different from the deterministic way in which classical physics proceeds, and means even the best calculations that physicists can come up with in regard to quantum experiments are mere probabilities.
The existence of free will as an element of consciousness also seems to be a deeply non-deterministic concept.
Recall that in mathematics, computer science, and physics, deterministic functions or systems involve no randomness in the future state of the system; in other words, a deterministic function will always yield the same results if you give it the same inputs.
Meanwhile, a nondeterministic function or system will give you different results every time, even if you provide the same input values.
However, Jeffrey Barrett, chancellor's professor of logic and philosophy of science at the University of California, Irvine, thinks the connection is somewhat arbitrary from the cognitive science side.
This rationalization isn't convincing to him, however.
From the quantum perspective, however, Barrett sees a clear reason why physicists first proposed the connection to consciousness.
At the heart of quantum "weirdness" and the measurement problem, there is a concept called "superposition."
Because the possible states of a quantum system are described using wave mathematics - or more precisely, wave functions - a quantum system can exist in many overlapping states, or a superposition. The weird thing is, these states can be contradictory.
To see how counter-intuitive this can be, we can refer to one of history's most famous thought experiments, the Schrödinger's Cat paradox.
Devised by Erwin Schrödinger, the experiment sees an unfortunate cat placed in a box with what the physicist described as a "diabolical device" for an hour.
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Treating the cat, box, and device as a quantum system with two possible states - "dead" or "alive" - before the box is opened, means it is in a superposition of those states .
The cat is both dead and alive before you open the container.
The problem of measurement asks,
Early quantum physicist Eugene Wigner thought so until shortly before his death in 1995.
In 1961, Wigner put forward a theory in which a mind was crucial to the collapse of a wave function and the destruction of superposition which persists in one form or another to this day.
Wigner and other physicists who adhered to the theory of conscious collapses - such as John von Neumann, John Wheeler, and John Bell - believed that an inanimate consciousness-less object would not collapse the wave function of a quantum system and would thus leave it in a superposition of states.
That means placing a Geiger counter in the box with Schrödinger's cat isn't enough to collapse the system to a "dead" or "alive" state even though it is capable of telling if the poison-release atom had decayed.
The superposition remains, Winger said, until a conscious observer opens the box or maybe hears the tick of the Geiger counter.
This leads to the conclusion that there are two distinct types of "substances" in the universe:
...with the human mind fitting in the latter category.
This suggests, though, that the brain is a physical and biological object, while the mind is something else, resulting in so-called "mind-body dualism."
For materialists like himself, Danielsson says,
This means it's quite possible for an "observer" to be a completely unconscious object.
This fits in with the fact that quantum systems are incredibly finely balanced systems easily collapsed by a stray electromagnetic field or even a change in temperature.
If you want to know why we don't have reliable quantum computers, that's a part of the reason:
Additionally, as Barrett points out, there are a number of ways of thinking about quantum mechanics that don't involve the collapse of quantum superposition.
The most famous, Hugh Everett III's many-worlds interpretation of quantum mechanics, suggests that when the experimenter makes a measurement, the wave function doesn't collapse at all.
Instead, it grows to include the experimenter and the entire universe, with one "world" for each possible state.
Thus, the experimenter opens the box not to discover if the cat is dead or alive, but rather, if they are in a world in which the cat survived or did not.
Clearly, with Noble Prize winners like Wigner and Roger Penrose persuaded that there may be something in a possible quantum-consciousness connection, however, the idea can't be entirely dismissed.
Kristian Piscicchia, a researcher at the Enrico Fermi Center for Study and Research in Rome, Italy, certainly agrees.
He is part of a team searching for a more profound understanding of the mind and the relationship between consciousness and the laws of nature.
This team recently set about testing one particular theory that connects consciousness to the collapse of quantum superposition - the Orchestrated Objective Reduction theory (Orch OR theory) - put forward by Nobel Laureate and Oxford mathematician Penrose and Arizona State University anesthesiologist Stuart Hameroff in the 1990s.
Orch OR theory considers quantum collapse to be related to gravity and argues this collapse actually gives rise to consciousness.
According to some approaches to Orch OR theory, the superposition collapse mechanism underlying it should cause the spontaneous emission of a tiny amount of radiation.
This distinguishes it from other quantum consciousness theories as it makes it experimentally testable.
Microtubules are a key element of eukaryotic cells that are critical for mitosis, cell motility, transport within cells, and maintaining cell shape. Hameroff's theory sees microtubules in brain neurons as the seat of quantum consciousness, maintaining quantum effects just long enough to conduct computations giving rise to consciousness before collapsing.
He adds that the results the team obtained place a constraint on the minimum amount of microtubulins needed for this form of Orch OR theory.
This limit was found to be prohibitively large, meaning the results indicate that many of the scenarios set out by Hameroff and Penrose's quantum consciousness theory are implausible.
Piscicchia points out that the team's work can't rule out all possibilities, however, and further testing is needed.
Yet, the existence of the quantum consciousness concept itself - and the way it is represented in popular culture - could present a threat to further scientific investigation.
The mind-body dualism suggested by quantum consciousness can be a potentially slippery slope that has led some proponents away from science and into the supernatural.
The concept has also been seized upon to explain the,
...giving rise to a cottage industry of "quantum mysticism."
The physicist also believes that it is definitely the case that the rise of quantum mysticism is hurting legitimate research.
Danielsson doesn't rule out that even if the mind is a purely emergent property of the brain, and thus completely physical in nature, the phenomenon of consciousness may require new physics to explain it.
He doesn't necessarily think that this needs to be quantum mechanics, however.
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