9.1 Substrate Independence: Why Can We Study the Universe’s Software (Laws), but Never Touch Its Hardware (Ontology)?

In previous chapters, we discussed civilization’s endgame—transforming themselves into underlying computational processes of the universe through virtual ascension. This inevitably raises a deeper, more unsettling question: If the universe allows “virtual ascension,” is our universe itself a simulated system that has already been “ascended” or constructed by some higher-order intelligence?

The “Simulation Hypothesis” was formally proposed by Nick Bostrom and has sparked intense debate in modern physics and philosophy. However, most discussions remain at the level of probabilistic arguments or science fiction speculation.

This chapter will attempt to transform this metaphysical question into a falsifiable physical problem based on QCA physical ontology. We will explore how to detect the hardware specifications of this “universe computer” we inhabit by searching for “numerical artifacts” in the universe’s code.

9.1.1 The Confusion of Conway’s Life

Imagine a glider in Conway’s Game of Life. It is a pattern composed of black and white grid points, moving according to simple local rules.

Suppose this glider gains intelligence and begins studying its universe.

• It discovers the speed of light (the maximum speed of glider movement).

• It discovers mass (the inertia of certain stationary structures).

• It even deduces the underlying cellular automaton rules (B3/S23).

But can it know through any experiment: Is this Game of Life running on a silicon-based Intel CPU, a wooden Turing machine, or in a biological brain’s dream?

The answer is: No.

This is Substrate Independence.

A computational system’s logical properties (software) are decoupled from its physical carrier (hardware).

$$f(x)=y$$

The truth of this computational process does not depend on whether the physical process executing it is electron flow, gear rotation, or quantum transitions.

9.1.2 Physical Laws as API

In the QCA universe, what we call “physical laws” (Schrödinger equation, Maxwell equations, Einstein equations) are essentially the Application Programming Interface (API) exposed by this universe computer to internal observers.

• API Specification: Defines how states evolve ($\hat{U}$).

• API Limits: Defines maximum call frequency (Planck time) and maximum data throughput (speed of light $c$).

As observers (software), we can only call these APIs to interact with the world. We can never “jump out” of the API to directly access underlying memory addresses or registers.

Just like Neo in “The Matrix,” without special “bugs,” he can only see the green code generated by the matrix, never the matrix server room.

9.1.3 Hardware’s Unknowability and the Void of Reality

This brings a profound philosophical consequence: The “substance” of physical reality is unknowable.

Traditional materialism holds that the world is composed of some “hard, substantial thing.”

But from a QCA perspective, this “hardness” is merely the rigidity of logical rules.

• Electrons are “hard” not because they are solid spheres, but because the Pauli exclusion principle (software rule) forbids two electrons from occupying the same state.

• Spacetime is “hard” not because it has elastic modulus, but because unitarity (software rule) forbids information loss.

If we strip away this layer of software rules, there may be nothing underneath—or rather, only pure mathematical forms.

This is why physics, as it develops, becomes increasingly like mathematics. Because mathematics is the science of studying structures, and the universe is ultimately a structure, not a material.

Conclusion:

We don’t need to search for the universe’s “hardware.” Because for software (us), logic is ontology, rules are existence.

Whether the universe runs in God’s brain or in the void of mathematical wave functions, for us, experience is real, causality is real, and that is enough.

However, this does not mean hardware leaves no traces. Just as even the most perfect simulator produces errors due to finite precision, if our universe is a product of finite resources, it must reveal itself under extreme conditions. In the next section, we will explore how to glimpse hardware secrets through “numerical artifacts.”