Coming to Grips with the Implications of Quantum Mechanics

Coming to Grips with the Implications of Quantum Mechanics

• By Bernardo Kastrup, Henry P. Stapp, Menas C. Kafatos on May 29, 2018
  

The claim is thus that the dynamics of all inanimate matter in the universe correspond to transpersonal mentation, just as an individual’s brain activity—which is also made of matter—corresponds to personal mentation. This notion eliminates arbitrary discontinuities and provides the missing inner essence of the physical world: all matter—not only that in living brains—is the outer appearance of inner experience, different configurations of matter reflecting different patterns or modes of mental activity.

According to QM, the world exists only as a cloud of simultaneous, overlapping possibilities—technically called a “superposition”—until an observation brings one of these possibilities into focus in the form of definite objects and events. This transition is technically called a “measurement.” One of the keys to our argument for a mental world is the contention that only conscious observers can perform measurements.

Some criticize this contention by claiming that inanimate objects, such as detectors, can also perform measurements, in the sense described above. The problem is that the partitioning of the world into discrete inanimate objects is merely nominal. Is a rock integral to the mountain it helps constitute? If so, does it become a separate object merely by virtue of its getting detached from the mountain? And if so, does it then perform a measurement each time it comes back in contact with the mountain, as it bounces down the slope? Brief contemplation of these questions shows that the boundaries of a detector are arbitrary. The inanimate world is a single physical system governed by QM. Indeed, as first argued by John von Neumann and rearticulated in the work of one of us, when two inanimate objects interact they simply become quantum mechanically “entangled” with one another—that is, they become united in such a way that the behavior of one becomes inextricably linked to the behavior of the other—but no actual measurement is performed.

Let us be more specific. In the well-known double-slit experiment, electrons are shot through two tiny slits. When they are observed at the slits, the electrons behave as definite particles. When observed only after they’ve passed through slits, the electrons behave as clouds of possibilities. In 1998, researchers at the Weizmann Institute in Israel showed that, when detectors are placed at the slits, the electrons behave as definite particles. At first sight, this may seem to indicate that measurement does not require a conscious observer.

However, the output of the detectors only becomes known when it is consciously observed by a person. The hypothesis of a measurement before this conscious observation lacks compelling theoretical or empirical grounding. After all, as discussed above, QM offers no reason why the whole system—electrons, slits and detectors combined—wouldn’t be in an entangled superposition before someone looks at the detectors’ output.

As such, a conscious observer may be indispensable, an idea further elaborated by one of us with regard to so-called “delayed choice quantum eraser” experiments. The bottom line is that we cannot know that detectors actually perform measurements, for we cannot abstract ourselves out of our knowledge. Recall Max Planck’s position: “I regard consciousness as fundamental. I regard matter as derivative from consciousness. We cannot get behind consciousness.” (Emphasis added.)

Some claim that the modern notion of “decoherence” rules out consciousness as the agency of measurement. According to this claim, when a quantum system in a superposition state is probed, information about the overlapping possibilities in the superposition “leaks out” and becomes dispersed in the surrounding environment. This allegedly explains in a fairly mechanical manner why the superposition becomes indiscernible after measurement.

The problem, however, is that decoherence cannot explain how the state of the surrounding environment becomes definite to begin with, so it doesn’t solve the measurement problem or rule out the role of consciousness. Indeed, as Wojciech Zurek—one of the fathers of decoherence—admitted,

…an exhaustive answer to [the question of why we perceive a definite world] would undoubtedly have to involve a model of ‘consciousness,’ since what we are really asking concerns our [observers’] impression that ‘we are conscious’ of just one of the alternatives.

Not sure if Stapp is arguing for a full-blown Idealism, his work rather suggests a Whitehead-esque metaphysics:

Physicalism versus Quantum Mechanics

Henry Stapp, Theoretical Physics Group Lawrence Berkeley National Laboratory University of California Berkeley, California 94720

In the context of theories of the connection between mind and brain, physicalism is the demand that all is basically purely physical. But the concept of "physical" embodied in this demand is characterized essentially by the properties of the physical that hold in classical physical theories. Certain of these properties contradict the character of the physical in quantum mechanics, which provides a better, more comprehensive, and more fundamental account of phenomena. It is argued that the difficulties that have plaged physicalists for half a century, and that continue to do so, dissolve when the classical idea of the physical is replaced by its quantum successor. The argument is concretized in a way that makes it accessible to non-physicists by exploiting the recent evidence connecting our conscious experiences to macroscopic measurable synchronous oscillations occurring in well-separated parts of the brain. A specific new model of the mind-brain connection that is fundamentally quantum mechanical but that ties conscious experiences to these macroscopic synchronous oscillations is used to illustrate the essential disparities between the classical and quantum notions of the physical, and in particular to demonstrate the failure in the quantum world of the principle of the causal closure of the physical, a failure that goes beyond what is entailed by the randomness in the outcomes of observations, and that accommodates the efficacy in the brain of conscious intent.

The switch from classical mechanics to quantum mechanics preserves the idea that a physical system has a physically describable state. But the character of that state is changed drastically. Previously the physical state was conceived to have a well defined meaning independently of any “observation”. Now the physically described state has essentially the character of a “potentia” (an “objective tendency”) for the occurrence of each one of a continuum of alternative possible “events”. Each of these alternative possible events has both an experientially described aspect and also a physically described aspect: each possible “event” is a psycho-physical happening. The experientially described aspect of an event is an element in a person’s stream of consciousness, and the physically described aspect is a reduction of the set of objective tendencies represented by the prior state of that person’s body-brain to the part of that prior state that is compatible with the increased knowledge supplied by the new element in that person’s stream of consciousness. Thus the changing psychologically described state of that person’s knowledge is correlated to the changing physically described state of the person’s body-brain, and the changing physically described state entails, via the fundamental quantum probability formula, a changing set of weighted possibilities for future psycho-physical events.