Chapter 1: The Nature of Reality

The idea that our universe might consist of more than mere information has sparked considerable debate. John Wheeler, a prominent physicist, was a strong advocate for the notion that the universe is fundamentally information-based. He famously asserted, “it from bit.” During a lecture at the Santa Fe Institute in 1989, he expressed that every entity—whether a particle, a field of force, or even the fabric of spacetime—derives its existence and meaning from binary responses to yes-or-no questions posed by our measuring instruments.

The core inquiry revolves around whether the universe can be entirely expressed through this binary framework or if there exists a more profound essence that transcends any collection of bits. This question is pivotal not only for our grasp of reality's fundamental nature but also for determining whether a flawless simulation of existence is achievable. Is it conceivable for a species to create a universe comprised solely of information filled with conscious entities?

Wheeler's perspective can be interpreted as a realist assertion, suggesting that the universe is discrete, composed of individual bits of information. However, quantum theory complicates this view by positing that these bits should be regarded as quantum bits, or qubits. In the quantum domain, a yes-no question does not yield a simple yes or no answer; rather, it results in both possibilities with assigned probabilities.

Qubits are characterized by quantum properties, and typically, each quantum particle exhibits both discrete and continuous attributes. Nonetheless, the attempt to measure quantum properties introduces complexity. Although the measured values seem discrete, they do not inherently represent that way. For instance, an electron's spin can adopt any value along the x, y, and z axes. Only when we measure one of these dimensions do we obtain a binary outcome: either up or down.

As such, we can assert that the electron has a binary spin in each dimension, albeit excluding the fact that our measurement apparatus is oriented in a specific manner. When we consider both the measuring device and the particle as a cohesive system, we uncover a continuum of spin values.

However, Wheeler's original point diverges from this realist interpretation. He emphasized that the apparatus is the one posing yes-no questions, while the electron merely provides responses. In subsequent discussions, he likened reality to a guessing game of 20 questions, where our inquiries into the quantum realm yield only binary answers, regardless of the formulation of the questions.

Consider this analogy: if I were to ask an astronaut floating in space whether they are moving left or right, their response would be contingent on my perspective. While the answer may seem logical, it reveals only what I perceive, not the astronaut's intrinsic state.

A realist might argue that my question elicits a relative answer concerning a deeper reality. Conversely, an anti-realist might contend that the response constitutes the entirety of the situation—left or right, without further context.

The same dynamics apply to quantum experiments. They provide answers not rooted in an inherent reality but shaped by our perspective.

Wheeler often faced accusations of being an anti-realist due to this viewpoint. He suggested that the universe lacks intrinsic reality, offering responses solely based on our inquiries—yes or no, contingent on how we frame them. From this angle, the universe can be viewed as binary information, as our understanding consists exclusively of bits that are always relative to our questioning approach, implying there is no reality beyond that.

Although Wheeler's intellectual prowess is undeniable, his position represents just one perspective among many. His anti-realist stance conflates scientific hypotheses with the reality that scientists endeavor to comprehend.

This viewpoint does not necessarily provide a realist alternative; rather, it acknowledges that the physical apparatuses we construct for specific yes-no questions do not equate to those queries. While we may utilize the apparatus to represent a question, it remains indifferent to what we seek to uncover. Similarly, the particle is unaffected by the questions we pose.

We perceive ourselves as beings interrogating the cosmos, and this is embedded in the very concept of "question and answer." This skill serves a vital function for survival. We have evolved to analyze animal tracks, deducing information about their movements, as well as evaluating plants and fruits for edibility, and assessing the friendliness of others based on clan or tribe affiliations.

Yet, envision a species that perceives itself as unified with the cosmos, devoid of any notion of separation. Such a species may lack the capacity to extract information from the universe, as they would already embody all existing knowledge. Any experimental outcome, therefore, would be a tautology—merely affirming what they, as part of the universe, already understand. A tautology carries no new information because information only arises when alternatives exist within data. (From this viewpoint, mathematics lacks informational value as it is entirely tautological; there are no choices in deriving a proof regarding what is true or false.)

If information is absent, how can the universe consist of it? The conclusion is that it cannot. Instead, our species has evolved to adopt a perspective wherein we interrogate the cosmos and extract information, thereby conceptualizing information as a measure of something so intuitive that we fail to recognize any alternative—much like how we cannot envision 1+1 equating to 3.

You might wonder: what about qubits? Doesn’t the universe make a choice when we observe phenomena? Doesn’t that generate information? However, this remains uncertain. No one has directly observed both a 0 and a 1 in superposition, existing simultaneously. Our understanding of superposition is inferred from various assumptions about reality; challenge those assumptions, and superposition may cease to exist.

This hypothetical species would likely form entirely different conclusions regarding quantum events. They might lean towards a superdeterministic interpretation, which challenges the separation between our decisions and the physical reality we measure. A species that sees itself as one with the universe would likely find this concept entirely acceptable. Importantly, superdeterminism does not need to be "true" for the argument to hold; it merely needs to align consistently with quantum experiments.

Ultimately, one must conclude that the universe is not constructed from information. In fact, it may contain no information whatsoever. It is purely physical, and our experience of physical reality is fundamentally that—an experiential one, rather than an informational one. Our sensations, not bits, shape our understanding.

Human cognition has evolved to layer 1's and 0's over sensations, leading us to conflate these bits with the sensations themselves. This confusion mirrors a child's attempt to depict their parents using simple stick figures; we mistake our simplified representation for the true essence of pure perception, which transcends all interpretation. Reality encompasses so much more—and yet so much less—than we may realize.

Wheeler, John Archibald. Information, physics, quantum: The search for links. CRC Press, 2018.

Chapter 2: The Universe's Limitations

In understanding the boundaries of our universe, we encounter questions about whether we are alone in the cosmos.

The first video, "Is our universe the only universe? - Brian Greene," delves into the potential for multiple universes and what that means for our understanding of existence.

As we explore these concepts, we also consider our place in the universe and the possibility that we might indeed be isolated.

The second video, "Why we might be alone in the Universe," examines the factors that suggest we may be the only intelligent life in the vast cosmos.