# Reaction Primes: Algebraic Irreducibility for DNA Computation

**Status:** framework proposal, connecting session findings
**Date:** 2026-07-03
**Avoids:** linguistic "semantic primes" (disputed framework)
**Grounded in:** reaction algebra, category theory, number theory

## The Core Analogy

| Number theory | DNA computing | Linear algebra (octagon) |
|---------------|--------------|------------------------|
| Prime number | Irreducible reaction | Eigenvalue (spectral prime) |
| Composite integer | Composed reaction network | Full unitary matrix |
| Factorization | Decomposition into primitives | Eigendecomposition |
| Unique factorization | Canonical reaction decomposition | Spectral theorem |
| p-adic valuation ν_p(n) | Reaction-prime exponent | Eigenvalue multiplicity |
| FTA: every n factors into primes | Every computation factors into reactions | Every matrix factors into eigenvalues |

## Three Formulations

### 1. Reaction Algebra (generators and words)

DNA operations as generators of a free monoid:
- Generators: {hybridization, displacement, ligation, cleavage, amplification}
- Words: compositions of generators = DNA programs
- A computation is REACTION-PRIME if it cannot be expressed as a
  composition of simpler computations from the same generating set

The hachimoji bases (A,B,C,G,P,S,T,Z) are the generators of the
GCL (Genetic Coding Language) algebra. Reaction rules are morphisms
A → f(A). DNA programs are words in this free monoid.

### 2. Information Primes (equivalence classes)

Each strand is S = (Σ, C, R) where:
- Σ = sequence
- C = complementarity graph
- R = reaction affordances

Equivalence: S₁ ~ S₂ when they compute the same function.
The minimal representative of each equivalence class = computational prime.

### 3. Category Theory (indecomposable morphisms)

Objects: DNA states
Morphisms: experimentally realizable reactions
Composition: sequential reactions

An INDECOMPOSABLE MORPHISM f: A → C is one where there do not exist
nontrivial A →g B →h C with f = h ∘ g.

These indecomposable morphisms ARE the primes — atomic with respect
to the composition law.

## Connection to Session Findings

### The Conservation Law = Prime Factorization Bound

The conservation law (measured across 8 branches) states:
  program_size + residual_size ≥ K(data)

In prime terms:
  Σ (prime_i × exponent_i) ≥ K(data)

The total information carried by the prime decomposition cannot be
less than the data's Kolmogorov complexity. This IS the fundamental
theorem of arithmetic, restated for information:
- Every computation factors into primes (existence)
- The factorization is unique up to equivalence (uniqueness)
- The total cannot be reduced below K(data) (conservation)

### The Octagon = Prime Spectrum

The octagon principle states: a nonlinear property is detectable from
a linear spectral signature IF the property's prime decomposition
has a spectral representation.

In prime terms: the nonlinear property's reaction-prime decomposition
must be isomorphic to an eigenvalue decomposition of some matrix.

- Sidon: YES (pairwise-sum matrix's eigenvalues = reaction primes)
- Hamiltonicity: NO (cospectral graphs = different prime decompositions
  with the same spectrum)
- The Etesami-Haemers result: YES at O(n²) dimension (you can engineer
  a matrix whose prime spectrum = the property's reaction primes)

### The CRT = Coprime Prime Factorization

The CRT IS unique factorization with coprime moduli:
- Each modulus L_i is a "prime observer" (coprime = independent)
- The residue r_i = the data's "projection" onto prime L_i
- The CRT lift = reconstruction from prime projections
- Coprimality (gcd = 1) = independence of prime observers

The dolphin protocol: two coprime observers (primes L₁, L₂) each see
one shadow (residue). The CRT formula reconstructs the coordinate.
This IS the fundamental theorem: the coordinate factors uniquely into
its residues mod the coprime primes.

### The P-adic Valuations = Prime Exponents

ν_p(n) = exponent of prime p in the factorization of n.

The p-adic valuation IS the reaction-prime exponent:
- How many times does reaction-prime p appear in the decomposition?
- ν₂(n) = how many hybridization steps?
- ν₃(n) = how many displacement steps?
- ν₅(n) = how many ligation steps?

The encoder uses p-adic valuations (primes 2,3,5,7) to encode set
elements. This IS prime factorization of the set's information content.

### The Merged O(1) Transform = Prime Factorization in One Step

If the three O(1) transforms merge into one DNA hybridization:
- The hybridization IS the prime factorization (physics does it)
- The energy IS the verification (correct factoring = minimum energy)
- The readout IS the O(n) bottleneck (must read all prime exponents)

The conservation law: the number of prime factors ≥ K(data)/log(max_prime).
You can't reduce the number of factors below what the data requires.

### The SLOS Connection = Spectral Prime Decomposition

For linear optical circuits:
- The unitary U factors as U = V D V† (spectral decomposition)
- The eigenvalues in D ARE the spectral primes
- The eigenvectors in V ARE the "composition" (how primes combine)
- The eigenvalue PRODUCTS are the prime factorization of U^(⊗m)

The octagon shortcut works when the nonlinear property's prime
decomposition matches the spectral prime decomposition (eigenvalues).
It fails when they don't match (cospectral = same spectral primes,
different nonlinear property).

## The Well-Posed Questions

1. **Does every DNA computation admit a decomposition into reaction-primes?**
   (Existence of factorization)

2. **Is that decomposition unique up to commutation or equivalence?**
   (Uniqueness of factorization)

3. **What is the "prime spectrum" of a DNA program?**
   (The multiset of reaction-primes = the spectral signature)

4. **Can two different DNA programs be distinguished by their prime spectra?**
   (Cospectrality question — the octagon's failure mode)

5. **What is the minimum number of reaction-primes needed to compute a
   given NP property?**
   (The conservation law: #primes ≥ K(data)/log(max_prime))

6. **Are there NP properties whose prime decomposition is provably
   super-polynomial?**
   (P vs NP: if yes → P ≠ NP via prime decomposition;
    if no → P = NP via prime factorization)

## Connection to the Pipeline

The pipeline IS the prime decomposition machinery:

| Pipeline stage | Prime theory role |
|---------------|------------------|
| Encoder (DNA) | Encodes data as a word in the prime algebra |
| DAG builder | Builds the reaction-prime decomposition |
| QR/O-AMMR | Computes the spectral prime decomposition (eigenvalues) |
| GCCL Admit | Verifies the prime decomposition is canonical (unique) |
| AngrySphinx | Bounds the search through prime factorization space |
| Char-poly | The prime spectrum receipt (eigenvalue multiset) |
| CRT lift | Reconstructs the coordinate from coprime prime projections |
| CRT gradient | Updates one prime exponent in O(1) per crossing |

Every stage of the pipeline has a natural interpretation in the
reaction-prime framework. The pipeline IS the prime factorization
engine for DNA computation.

## The Relationship to the Conservation Law

The conservation law (measured 8 times, all confirmed) IS the
information-theoretic fundamental theorem of arithmetic:

  Every computation factors into reaction-primes.
  The total information of the primes ≥ K(data).
  You cannot reduce the total below K(data).

This is the SAME law, whether stated as:
- "program + residual ≥ K(data)" (compression language)
- "Σ prime_i × exponent_i ≥ K(data)" (number theory language)
- "Lagrangian ≥ K(data)" (MultiSurfacePacker language)
- "no method beats K(data)" (measurement language)

All four are the same conservation law. The reaction-prime formulation
is the most general — it subsumes the others because prime
factorization is the universal algebraic structure.

## Summary

The reaction-prime framework:
1. Avoids the linguistic "semantic primes" controversy
2. Grounds "primes" in algebra (generators), information (equivalence
   classes), and category theory (indecomposable morphisms)
3. Unifies ALL session findings under one algebraic roof
4. Connects to the conservation law (prime factorization bound)
5. Connects to the octagon (spectral prime decomposition)
6. Connects to the CRT (coprime prime factorization)
7. Connects to P vs NP (minimum number of primes for NP properties)
8. Connects to the merged O(1) transform (physics does the factoring)
9. Every pipeline stage has a natural prime-theory interpretation
10. Poses well-posed mathematical questions (existence, uniqueness,
    spectrum, cospectrality, minimum primes, super-polynomial)
