Consciousness refers to the subjective experience of the self and its surroundings, including sensory perception, thinking, and emotions. Philosophers have been exploring the nature and origin of consciousness, but scientists have not given up searching for an objective explanation. In physics, there are two main theories for describing phenomena in nature: classical mechanics and quantum mechanics.
Classical mechanics was established by Newton and others, and it applies to macro-scale objects such as planets, cars, or apples. Classical mechanics states that the position and velocity of objects can be accurately measured and predicted, and that objects can only interact with each other through direct contact.
Quantum mechanics was developed in the early 20th century and is applied to particles at the microscopic scale, such as electrons, photons, or atoms. Quantum mechanics holds that the position and velocity of particles are uncertain and can only be described in terms of probabilities. In addition, quantum mechanics reveals some bizarre phenomena such as superposition, entanglement, and tunneling.
In the double-slit experiment, a coherent photon beam propagated from light source A shines on an opaque baffle S2 engraved with two slits b and c, behind which photographic film or some kind of detection screen F is placed to record photon data reaching anywhere d in F. The black-and-white stripe on the far right shows the interference pattern of photons in the detection screen F.
Overlay means that a particle can be in two or more states at the same time, such as rotating up and down at the same time. Entanglement is a kind of action between two or more particles at a distance that can affect each other even if they are far apart. Tunneling is when a particle can pass through a seemingly insurmountable barrier, such as an electron jumping from one atom to another.
So, is human consciousness governed by classical mechanics or quantum mechanics? This question has been the subject of debate and conjecture among many scientists and philosophers. One of the most influential theories was proposed by physicist Roger Penrose and anesthesiologist Stuart Hameroff in the 90s.
The Penrose-Hameroff theory suggests that neurons in the human brain contain structures called microtubules, which are responsible for transporting matter to different parts of the cell. They believe that microtubules have a pattern of fractals, which allows them to carry out quantum processes. A fractal is a structure that is neither two-dimensional nor three-dimensional, but is some decimal value in between. In mathematics, fractals take on beautiful patterns that repeat themselves infinitely, producing a seemingly impossible situation: a structure with a finite area but infinite perimeter.
The Penrose-Hameroff theory further argues that quantum processes in microtubules are coordinated with the neural activity in the brain that produce consciousness and are governed by fundamental laws of physics, such as general relativity. They believe that when quantum states in microtubules reach a tipping point, they undergo a process called quantum state collapse, which is the generation of consciousness. Quantum state collapse is when a particle chooses a definite state from a number of possible states, such as rotating up and down at the same time to rotating only up or down.
The Penrose-Hamerov theory attempts to use quantum mechanics to explain the complexity and non-algorithmic nature of human consciousness. Complexity refers to the diversity, flexibility, and creativity of consciousness, while non-algorithmic means that consciousness cannot be simulated by simple computational rules. They argue that classical mechanics is not enough to describe consciousness because it is deterministic, linear, and reversible, while quantum mechanics is uncertain, nonlinear, and irreversible.
The Penrose-Hamerov theory has caused a lot of controversy in the scientific community. Some scientists see it as a bold and creative endeavor, while others see it as an unsubstantiated conjecture. One of the main challenges in the theory of quantum consciousness is how to verify it experimentally. Currently, we don't have instruments precise and sensitive enough to measure microscopic quantum effects in the brain, and it's not clear whether temperature, humidity, and noise in the brain disrupt quantum coherence in microtubules.
In the classical scattering of ambient photons to target objects, on average, the motion of the target object does not change due to the action of the scattered photons. In quantum scattering, the scattered photons interact with the target object in the superposition state, which leads to quantum entanglement and delocalizes the phase coherence of the target object to the entire system. Causes the interference pattern to disappear without a trace.
Still, some scientists are struggling to find evidence to support or refute the quantum consciousness theory. For example, Professor Jin Xianmin of Shanghai Jiao Tong University tested some basic principles of quantum consciousness theory in the laboratory.
If we can compare our findings to measured activity in the brain in the future, we may be closer to validating or refuting the Penrose-Hameroff theory. Of course, this is only a preliminary exploration, and there are still many problems to be solved. Is human consciousness classical or quantum? There is no definitive answer to this question yet, but it is worth continuing to explore and ponder.
Reference:
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