Memetic Computing Theory¶
Comprehensive guide to the theoretical foundations of Q-Memetic AI, including memetic evolution, genetic algorithms, and quantum-inspired computing principles.
Introduction to Memetic Computing¶
Memetic computing combines the power of evolutionary algorithms with local search techniques, inspired by Richard Dawkins' concept of memes as units of cultural transmission. In Q-Memetic AI, we extend this concept to computational intelligence.
Core Principles¶
- Memes as Computational Units: Ideas are represented as high-dimensional vectors with semantic meaning
- Evolutionary Dynamics: Memes evolve through selection, mutation, and crossover operations
- Cultural Transmission: Memes propagate through networks and adapt to cognitive environments
- Quantum-Inspired Entanglement: Ideas become correlated through semantic similarity and interaction patterns
Meme Representation¶
Vector Encoding¶
Each meme is encoded as a multi-dimensional vector containing:
class MemeVector:
"""
Mathematical representation of a meme.
Attributes:
content_embedding: Dense semantic vector (384-1536 dimensions)
intent_vector: Purpose and goal representation (128 dimensions)
fitness_components: Multi-objective fitness scores
generation_info: Evolutionary metadata
"""
def __init__(self):
self.content_embedding = np.zeros(384) # Sentence transformer encoding
self.intent_vector = np.zeros(128) # Intent classification
self.fitness_components = {
'semantic_coherence': 0.0,
'novelty': 0.0,
'domain_relevance': 0.0,
'user_preference': 0.0
}
self.generation = 0
self.parent_ids = []
Semantic Embedding¶
Content is transformed into semantic vectors using state-of-the-art language models:
Where:
- \(m\) is a meme
- \(\\text{LM}_{\\text{encoder}}\) is a pre-trained language model encoder
- The resulting vector captures semantic meaning in high-dimensional space
Fitness Landscape¶
The fitness of a meme is calculated as a weighted combination of multiple objectives:
Where:
- \(F(m)\) is the overall fitness of meme \(m\)
- \(w_i\) are weights for each fitness component
- \(f_i(m)\) are individual fitness functions
Common fitness components:
- Semantic Coherence: \(f_1(m) = \\cos(\\text{Embedding}(m), \\text{Domain}_{\\text{centroid}})\)
- Novelty: \(f_2(m) = 1 - \\max_{m' \\in \\text{Population}} \\cos(\\text{Embedding}(m), \\text{Embedding}(m'))\)
- Domain Relevance: \(f_3(m) = \\text{Classifier}_{\\text{domain}}(\\text{content}(m))\)
- User Preference: \(f_4(m) = \\text{CognitiveModel}_{\\text{user}}(m)\)
Evolutionary Operators¶
Selection¶
Q-Memetic AI implements multiple selection strategies:
Tournament Selection¶
def tournament_selection(population, tournament_size=3):
"""
Select individuals through tournament competition.
Higher fitness memes have better chances of selection,
while maintaining diversity through random tournaments.
"""
selected = []
for _ in range(len(population)):
tournament = random.sample(population, tournament_size)
winner = max(tournament, key=lambda m: m.fitness)
selected.append(winner)
return selected
Roulette Wheel Selection¶
Where \(P(m_i)\) is the probability of selecting meme \(m_i\).
Rank-Based Selection¶
Where \(\\text{rank}(m_i)\) is the fitness rank of meme \(m_i\).
Mutation¶
Mutation introduces variation through LLM-powered content transformation:
def llm_mutation(meme, mutation_strength=0.5):
"""
Mutate meme content using large language models.
The mutation strength controls the degree of change:
- Low strength: Minor rephrasing
- High strength: Conceptual transformation
"""
prompt = f"""
Transform this idea while preserving its core meaning:
"{meme.content}"
Mutation strength: {mutation_strength}
Domain: {meme.metadata.domain}
"""
mutated_content = llm_generate(prompt, temperature=mutation_strength)
return meme.copy_with_content(mutated_content)
Mutation Operators¶
- Semantic Mutation: Preserves meaning while changing expression
- Structural Mutation: Alters sentence structure and organization
- Creative Mutation: Introduces novel concepts and metaphors
- Domain Transfer: Adapts ideas across different domains
Crossover¶
Crossover combines concepts from two parent memes:
def semantic_crossover(parent1, parent2, crossover_point=0.5):
"""
Combine semantic concepts from two parent memes.
Uses attention mechanisms to identify key concepts
and blend them coherently.
"""
# Extract key concepts using attention weights
concepts1 = extract_concepts(parent1.content)
concepts2 = extract_concepts(parent2.content)
# Blend concepts based on crossover point
blended_concepts = blend_concepts(concepts1, concepts2, crossover_point)
# Generate offspring content
offspring_content = generate_from_concepts(blended_concepts)
return create_offspring(offspring_content, [parent1, parent2])
Crossover Types¶
- Uniform Crossover: Random concept mixing
- Single-Point Crossover: Split at sentence boundaries
- Semantic Crossover: Blend semantic representations
- Attention-Weighted Crossover: Use attention scores for concept importance
Population Dynamics¶
Generational Models¶
Generational Evolution¶
def generational_evolution(population, generations):
"""
Replace entire population each generation.
Advantages: Clear generation boundaries
Disadvantages: Potential loss of good solutions
"""
for gen in range(generations):
# Selection
parents = select_parents(population)
# Reproduction
offspring = reproduce(parents)
# Replacement
population = offspring
# Elitism (preserve best individuals)
if elitism_enabled:
population = preserve_elite(population, elite_size)
Steady-State Evolution¶
def steady_state_evolution(population, evaluations):
"""
Replace individuals continuously.
Advantages: Maintains population diversity
Disadvantages: More complex implementation
"""
for _ in range(evaluations):
# Select parents
parents = select_parents(population, num_parents=2)
# Create offspring
offspring = reproduce(parents)
# Replace worst individuals
replace_worst(population, offspring)
Diversity Maintenance¶
Maintaining diversity prevents premature convergence:
Fitness Sharing¶
Where \(d(m_i, m_j)\) is the distance between memes and \(\\text{sharing}\) is a sharing function.
Niching¶
def niching_selection(population, niche_radius=0.1):
"""
Maintain multiple species/niches in population.
Prevents dominant solutions from taking over
the entire population.
"""
niches = cluster_population(population, niche_radius)
selected = []
for niche in niches:
# Select best from each niche
niche_best = max(niche, key=lambda m: m.fitness)
selected.append(niche_best)
return selected
Crowding¶
Replace similar individuals to maintain diversity:
def crowding_replacement(population, offspring):
"""
Replace most similar individuals with offspring.
Maintains population diversity by preventing
clustering around single solutions.
"""
for child in offspring:
# Find most similar individual
most_similar = find_most_similar(population, child)
# Replace if child is better
if child.fitness > most_similar.fitness:
population.replace(most_similar, child)
Multi-Objective Optimization¶
Meme fitness involves multiple conflicting objectives:
Pareto Dominance¶
Meme \(m_1\) dominates \(m_2\) if: \(\(f_i(m_1) \\geq f_i(m_2) \\quad \\forall i \\in \\{1, 2, ..., n\\}\)\) \(\(\\exists j : f_j(m_1) > f_j(m_2)\)\)
NSGA-II Integration¶
def nsga2_selection(population, objectives):
"""
Non-dominated Sorting Genetic Algorithm II
Ranks individuals by Pareto fronts and
maintains diversity through crowding distance.
"""
# Non-dominated sorting
fronts = non_dominated_sort(population, objectives)
# Calculate crowding distances
for front in fronts:
calculate_crowding_distance(front, objectives)
# Select individuals
selected = []
front_index = 0
while len(selected) + len(fronts[front_index]) <= population_size:
selected.extend(fronts[front_index])
front_index += 1
# Fill remaining slots by crowding distance
remaining = population_size - len(selected)
if remaining > 0:
last_front = sorted(fronts[front_index],
key=lambda m: m.crowding_distance,
reverse=True)
selected.extend(last_front[:remaining])
return selected
Convergence Analysis¶
Theoretical Guarantees¶
Under certain conditions, memetic algorithms converge to optimal solutions:
Schema Theorem¶
For genetic algorithms with binary encoding:
Where:
- \(m(S, t)\) is the number of individuals containing schema \(S\) at time \(t\)
- \(f(S)\) is the average fitness of schema \(S\)
- \(\\bar{f}\) is the average population fitness
- \(p_c\) is crossover probability
- \(p_m\) is mutation probability
- \(d(S)\) is the defining length of schema \(S\)
- \(o(S)\) is the order of schema \(S\)
Building Block Hypothesis¶
Good solutions are composed of good building blocks (partial solutions) that are:
- Short in defining length
- Low in order
- Above average in fitness
Empirical Convergence¶
Monitor convergence through multiple metrics:
def convergence_metrics(population_history):
"""
Calculate convergence indicators.
"""
metrics = {}
# Fitness convergence
best_fitness = [max(pop, key=lambda m: m.fitness).fitness
for pop in population_history]
metrics['fitness_improvement'] = best_fitness[-1] - best_fitness[0]
# Diversity metrics
diversity = [calculate_diversity(pop) for pop in population_history]
metrics['diversity_retention'] = diversity[-1] / diversity[0]
# Selection pressure
avg_fitness = [np.mean([m.fitness for m in pop])
for pop in population_history]
metrics['selection_pressure'] = np.std(best_fitness) / np.std(avg_fitness)
return metrics
Landscape Analysis¶
Fitness Landscape Properties¶
Understanding the search space helps optimize algorithm parameters:
Ruggedness¶
Measure fitness landscape smoothness:
Where \(x_i\) are points on a random walk through the landscape.
Neutrality¶
Proportion of mutations that don't change fitness:
Epistasis¶
Degree of interaction between components:
Where \(F_i\) is the contribution of component \(i\) to fitness.
Problem Decomposition¶
Break complex problems into subproblems:
def decompose_meme_problem(meme, decomposition_strategy="semantic"):
"""
Decompose meme optimization into subproblems.
Strategies:
- semantic: Based on semantic concepts
- structural: Based on linguistic structure
- domain: Based on domain expertise
"""
if decomposition_strategy == "semantic":
concepts = extract_semantic_concepts(meme.content)
subproblems = [optimize_concept(concept) for concept in concepts]
elif decomposition_strategy == "structural":
sentences = split_sentences(meme.content)
subproblems = [optimize_sentence(sent) for sent in sentences]
elif decomposition_strategy == "domain":
domain_aspects = extract_domain_aspects(meme)
subproblems = [optimize_aspect(aspect) for aspect in domain_aspects]
return subproblems
Hybrid Approaches¶
Combining evolutionary algorithms with local search:
Memetic Algorithm Framework¶
class MemeticAlgorithm:
"""
Hybrid evolutionary algorithm with local search.
Combines global exploration (evolution) with
local exploitation (hill climbing).
"""
def __init__(self, local_search_prob=0.1, local_search_intensity=10):
self.local_search_prob = local_search_prob
self.local_search_intensity = local_search_intensity
def evolve_population(self, population, generations):
for gen in range(generations):
# Standard evolutionary operations
population = self.evolutionary_step(population)
# Apply local search to selected individuals
for individual in population:
if random.random() < self.local_search_prob:
individual = self.local_search(individual)
return population
def local_search(self, individual):
"""
Improve individual through local search.
Uses gradient-based optimization in semantic space.
"""
current = individual
for _ in range(self.local_search_intensity):
# Generate neighbors
neighbors = self.generate_neighbors(current)
# Select best neighbor
best_neighbor = max(neighbors, key=lambda m: m.fitness)
# Move if improvement found
if best_neighbor.fitness > current.fitness:
current = best_neighbor
else:
break # Local optimum reached
return current
Local Search Strategies¶
- Hill Climbing: Greedy improvement
- Simulated Annealing: Probabilistic acceptance of worse solutions
- Tabu Search: Memory-based search with forbidden moves
- Variable Neighborhood Search: Systematic neighborhood change
Performance Analysis¶
Computational Complexity¶
Time Complexity¶
- Selection: \(O(N \\log N)\) for tournament selection
- Mutation: \(O(N \\cdot M)\) where \(M\) is mutation cost (LLM inference)
- Crossover: \(O(N \\cdot C)\) where \(C\) is crossover cost
- Fitness Evaluation: \(O(N \\cdot F)\) where \(F\) is fitness computation cost
Space Complexity¶
- Population Storage: \(O(N \\cdot D)\) where \(D\) is vector dimension
- Entanglement Network: \(O(N^2)\) for dense networks
- Evolution History: \(O(G \\cdot N)\) where \(G\) is generations
Scalability Analysis¶
def analyze_scalability(population_sizes, problem_dimensions):
"""
Analyze algorithm scalability across different parameters.
"""
results = {}
for pop_size in population_sizes:
for dimension in problem_dimensions:
start_time = time.time()
# Run algorithm
result = run_memetic_algorithm(
population_size=pop_size,
problem_dimension=dimension,
generations=100
)
runtime = time.time() - start_time
results[(pop_size, dimension)] = {
'runtime': runtime,
'final_fitness': result.best_fitness,
'convergence_generation': result.convergence_gen
}
return results
Theoretical Extensions¶
Advanced Concepts¶
Co-evolution¶
Multiple populations evolve simultaneously:
def competitive_coevolution(populations, generations):
"""
Evolve multiple populations that compete or cooperate.
Useful for:
- Adversarial scenarios
- Multi-stakeholder problems
- Ecosystem modeling
"""
for gen in range(generations):
# Evaluate fitness through interactions
interaction_results = evaluate_interactions(populations)
# Update fitness based on interactions
update_fitness_from_interactions(populations, interaction_results)
# Evolve each population
for i, pop in enumerate(populations):
populations[i] = evolve_population(pop)
Cultural Evolution¶
Ideas evolve at both individual and cultural levels:
class CulturalEvolution:
"""
Model cultural transmission and evolution.
Includes:
- Horizontal transmission (peer-to-peer)
- Vertical transmission (generation-to-generation)
- Oblique transmission (many-to-one)
"""
def __init__(self):
self.cultural_pool = []
self.transmission_networks = {}
def cultural_transmission(self, individuals, network):
"""
Transmit cultural memes through social networks.
"""
for individual in individuals:
# Select cultural memes to transmit
transmitted_memes = self.select_transmission_memes(individual)
# Find transmission targets
targets = network.get_neighbors(individual)
# Transmit with cultural bias
for target in targets:
for meme in transmitted_memes:
if self.accept_transmission(target, meme):
target.cultural_memes.append(meme)
Future Directions¶
- Quantum Computing Integration: True quantum algorithms for meme evolution
- Neural Architecture Evolution: Evolving neural networks for meme processing
- Multi-Modal Memes: Beyond text to images, audio, and video
- Real-Time Adaptation: Continuous evolution in live systems
- Ethical AI: Ensuring beneficial meme evolution
Mathematical Foundations¶
Information Theory¶
Measure information content and diversity:
Shannon Entropy¶
For population diversity: \(\(H_{\\text{pop}} = -\\sum_{i=1}^{n} p(m_i) \\log_2 p(m_i)\)\)
Mutual Information¶
For meme correlation: \(\(I(m_1;m_2) = \\sum_{v_1,v_2} p(v_1,v_2) \\log \\frac{p(v_1,v_2)}{p(v_1)p(v_2)}\)\)
Graph Theory¶
Network properties and analysis:
Centrality Measures¶
- Degree Centrality: \(C_D(v) = \\frac{\\deg(v)}{n-1}\)
- Betweenness Centrality: \(C_B(v) = \\sum_{s \\neq v \\neq t} \\frac{\\sigma_{st}(v)}{\\sigma_{st}}\)
- Eigenvector Centrality: \(C_E(v) = \\frac{1}{\\lambda} \\sum_{u \\in N(v)} C_E(u)\)
Small World Properties¶
- Clustering Coefficient: \(C = \\frac{1}{n} \\sum_{v} C_v\)
- Average Path Length: \(L = \\frac{1}{n(n-1)} \\sum_{i \\neq j} d_{ij}\)
- Small World Index: \(S = \\frac{C/C_{\\text{random}}}{L/L_{\\text{random}}}\)
Applications and Case Studies¶
Research Applications¶
- Scientific Discovery: Evolving research hypotheses
- Literature Review: Synthesizing research findings
- Peer Review: Improving manuscript quality
- Grant Writing: Optimizing proposal narratives
Educational Applications¶
- Curriculum Design: Evolving educational content
- Personalized Learning: Adapting to student needs
- Assessment: Creating better evaluation methods
- Knowledge Transfer: Optimizing explanation strategies
Creative Applications¶
- Content Generation: Evolving stories and articles
- Artistic Collaboration: AI-human creative partnerships
- Marketing: Optimizing messaging and campaigns
- Entertainment: Interactive narrative systems
Conclusion¶
Memetic computing in Q-Memetic AI represents a novel approach to computational intelligence that combines:
- Evolutionary principles for robust optimization
- Semantic understanding through modern NLP
- Network effects for idea propagation
- Quantum inspiration for enhanced correlation modeling
This theoretical foundation enables powerful applications in research, education, creativity, and beyond, while maintaining mathematical rigor and computational efficiency.
References and Further Reading¶
- Dawkins, R. (1976). The Selfish Gene. Oxford University Press.
- Moscato, P. (1989). On Evolution, Search, Optimization, Genetic Algorithms and Martial Arts.
- Deb, K. (2001). Multi-Objective Optimization using Evolutionary Algorithms.
- Goldberg, D. E. (1989). Genetic Algorithms in Search, Optimization, and Machine Learning.
- Mitchell, M. (1996). An Introduction to Genetic Algorithms.
For implementation details, see the API Reference and Usage Guide.