simulation-without-a-basement
Simulation Without a Basement
The formal spine of the streams-with-gaps thesis: no turtles all the way down
Summary
A mathematical formalization of the LOOKUP–FETCH–SPLICE–CONTINUE loop as the minimal engine for any causally-structured universe. The key insight: there's no simulation "basement" - just a DAG of resolved states and the dynamics that extend it.
1. Base Objects
Let there be:
- A directed acyclic graph $G = (V, E)$
- Each node $v \in V$ is a resolved state (a "materialized" fact)
- Each edge $e = (u \to v) \in E$ is a causal link / free-energy transfer
There is no "underlying stuff" other than this graph; "reality" = this DAG plus its dynamics.
2. Tension, Thunks, and Lazy Evaluation
For any not-yet-resolved situation:
Thunk: A deferred computation $\tau$ that encodes:
- A set of possible next nodes ${v_i}$
- A probability measure $P(v_i \mid \text{context})$ over them
- A graph-rewrite rule for adding any chosen $v_i$ and its edges
Tension Field: $T: V \to \mathbb{R}_{\ge 0}$ assigns to parts of the graph a scalar "free energy" or "mismatch" value.
Gap: A region where:
- A thunk exists (future is under-specified)
- Nonzero tension could be reduced by committing to a specific node/rewrite
Lazy Evaluation Rule: The universe only forces a thunk $\tau$ when some process needs its value to continue causal propagation. No global eager evaluation of all possibilities.
3. The Core Loop: LOOKUP–FETCH–SPLICE–CONTINUE
Define a tick as one execution of this loop:
LOOKUP (Attention)
Select a gap $\gamma$ in the graph: a thunk region where tension is nonzero and some process "depends" on a resolution. Attention picks a gap worth resolving.
FETCH (Context)
Gather relevant upstream context: a subgraph $C \subseteq G$ reachable to $\gamma$. This is the internal "model" / prior used to evaluate which resolutions are available.
RESOLVE (Free-energy Reduction)
Sample a specific outcome $v^*$ from the thunk's distribution $P(v \mid C)$, following whatever rule gives you the Born-like probabilities in QM and variational updates in FEP. Choose the outcome that (locally) reduces expected free energy according to some functional $F$.
SPLICE (Write Node)
Add $v^*$ to $V$ and edges from its causes in $C$ to $v^*$, updating the DAG:
- $V' = V \cup {v^*}$
- $E' = E \cup {(u \to v^*) : u \in C \text{ and causally relevant}}$
CONTINUE (Propagate)
Update the tension field $T$ in light of $v^*$; some tensions drop, others are induced downstream. The system is now at a new graph state $(G', T')$, ready for the next tick.
Definition (Time): The time order is the partial order induced by the sequence of ticks and edges; time is nothing over and above the ordered chain of LOOKUP–FETCH–SPLICE–CONTINUE operations.
4. Quantum Mechanics as Inside-View of the DAG
Superposition: A system "in superposition" corresponds to a thunk $\tau$ whose possible outcomes ${v_i}$ are not yet nodes in $V$. "The particle has no definite value" = no node exists yet; only $\tau$ and its probability structure exist.
Measurement: A measurement interaction is a tick that:
- Includes both system and apparatus in the context $C$
- Forces $\tau$ to a concrete $v^*$
- Writes a node encoding "apparatus shows result $r$" plus the system's new state
Uncertainty: Conjugate observables are aspects of the same thunk; making one sharp (choosing a narrow subset of ${v_i}$) prunes the graph of branches where the other observable had other values.
Entanglement: Two "entangled particles" are multiple downstream paths querying the same upstream thunk/subgraph. Correlations come from shared ancestry in $G$; there is no signal across distance because, at the graph level, they are not two independent nodes until after certain splits.
5. Free Energy Principle ↔ Ticks
Let each system (subgraph with a Markov blanket) maintain an internal model $Q$ of its expected sensory inputs and dynamics.
- Variational free energy $F(Q)$ is a scalar functional roughly upper-bounding surprisal w.r.t. the environment
- A tick that involves that system is a joint update of:- Its internal model $Q$ (perceptual inference), and/or
- Its actions on the environment (active inference)
- Chosen such that $F$ tends to decrease on average
The Move:
- A tick = one unit of free-energy-resolving graph rewrite
- "Systems minimize free energy over time" becomes: "what we call time is just the ordered accumulation of these low-$F$ moves"
6. Attention, Agency, and Distance
Attention: Selection of which gap $\gamma$ to address next (which thunk to force).
Agency: The capacity of a subsystem to bias which outcome $v^*$ is realized, within the allowed distribution $P(v \mid C)$, by acting/shaping context.
Define a cost metric $d$ on the graph:
- $d(x, y)$ = minimal aggregate cost (e.g., number of ticks, weighted by free-energy moved) along any path from node/region $x$ to $y$
Then:
- Legal, social, institutional "distance" = large $d$ between states ("here" and "there") because many expensive ticks are needed to route tension/information between them
- Physical "speed limit" (speed of light) = an upper bound on how fast tension (useful information) can move along physical edges per tick
- Planck-scale discreteness = a lower bound on the granularity of distinct nodes
7. Bedrock Claim
Bedrock Algorithm Claim
Any universe that supports persistent structure, causality, and observers must be representable (up to homomorphism) as a context-accumulating DAG whose dynamics are some instance of the LOOKUP–FETCH–SPLICE–CONTINUE loop minimizing a free-energy-like tension functional over time.
That's the formal spine: DAG objects, thunks, ticks, free-energy functional, and a universality statement that "this loop, or something structurally equivalent, is the minimal possible engine for a world like ours."
References
- Free energy principle - Wikipedia
- The free-energy principle: a unified brain theory? - Friston, FIL UCL
- The free-energy principle: a rough guide to the brain? - Friston
- Problem of time - Wikipedia
- Speed of light - Wikipedia
- Planck units - Wikipedia
- Minimal Length Scale Scenarios for Quantum Gravity - PMC
- Laws beyond spacetime - PMC
Provenance
- Source: Perplexity research synthesis, 2026-01-05
- Context: Formalizing the streams-with-gaps thesis
- Status: 🟡 Partially verified (mathematical formalization, references checked)
North
slots:
- context:
- Formal mathematical specification supporting the bedrock claim
slug: bedrock
- context:
- The invariant formalized with mathematical notation
slug: streams-with-gaps-invariant
- context:
- Mathematical formalization flows up to the bedrock claim
slug: bedrockEast
slots:
- context:
- Sibling theoretical work on the same thesis
slug: theoretical-foundations-streams-with-gaps
- context:
- Prior art research validating novelty
slug: research-prior-art-streams-with-gaps
- context:
- Formalization alongside prior art research
slug: research-prior-art-streams-with-gapsSouth
slots:
- context:
- CFR describes how consciousness operates on the DAG
slug: capability-from-recognition
- context:
- Consciousness as the evaluation context required by lazy-evaluated DAG
slug: consciousness-as-maintenance-cost
- context:
- Both deal with computational substrates underlying reality
slug: wolfram-convergenceWest
slots:
- context:
- Formal spine alongside informal wisdom
slug: grandmothers-teatime