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29.4 Evolutionary LLM Search and Scientific Discovery

The previous sections covered RL's traditional frontiers — embodied intelligence, self-play, multi-agent systems. This section turns to a different direction altogether: LLM-driven scientific discovery.

Three things define this direction:

  • The LLM takes on more than the actor role — it also works as idea generator, code writer, and experiment designer
  • RL takes on more than policy optimization — it drives search, evolution, self-improvement
  • The target is not gameplay or dialogue — it's discovering new algorithms, new mathematics, new science

A few representative works from 2024–2026:

  • AlphaEvolve (DeepMind, May 2024): LLM + evolutionary algorithms discover new mathematics
  • Genie 3 (DeepMind, August 2025): a generative world model
  • Titans (Google, December 2024): a long-term memory architecture
  • Multi-Agent Deep Research (ByteDance Seed, November 2025): trains multi-agent search systems with M-GRPO

Together these works represent the "next-generation paradigm" for combining RL with LLMs — the object of training shifts from "a policy" to "a research system."

29.4.1 AlphaEvolve and Mathematical Discovery via LLM + Evolution

AlphaEvolve (DeepMind, announced May 2024, full version 2025) is the flagship case of LLM-driven scientific discovery.

The Core Idea Behind AlphaEvolve

It models mathematical discovery as evolutionary search plus LLM code generation:

text
┌─────────────────────────────────────────────────────────────┐
│ 1. Population initialization: existing algorithms/proofs    │
│    (e.g., Strassen's algorithm for matrix multiplication)   │
├─────────────────────────────────────────────────────────────┤
│ 2. LLM mutation: have Gemini generate branches               │
│    "Improve this algorithm" / "Try a different approach"    │
│    Output: new code                                         │
├─────────────────────────────────────────────────────────────┤
│ 3. Automatic evaluation: run the code, measure its effect   │
│    (e.g., number of multiplications used)                   │
├─────────────────────────────────────────────────────────────┤
│ 4. Selection: keep what performs well, discard what doesn't │
├─────────────────────────────────────────────────────────────┤
│ 5. Iterate: return to step 2                                │
└─────────────────────────────────────────────────────────────┘

This loop is almost identical to a classic genetic algorithm (GA) — the only difference is that the mutation operator changes from "random tweaks" to "intelligent LLM generation."

AlphaEvolve's Key Innovations

Innovation 1: the LLM as an intelligent mutation operator

Mutation in a traditional GA is a random edit — its success rate is low. Mutation by an LLM means "understand the current code and propose a meaningful improvement" — its success rate is much higher.

Innovation 2: code as the gene

Instead of using a bit string as the gene, AlphaEvolve uses executable code. This makes fitness automatically measurable — running the code tells you how well it performs.

Innovation 3: Gemini as the LLM backend

AlphaEvolve runs Gemini Pro/Ultra as its LLM backend — a strong LLM substantially raises the quality of each mutation.

What AlphaEvolve Discovered

AlphaEvolve produced genuinely new discoveries across several domains.

Discovery 1: a new matrix multiplication algorithm

In 1969, Strassen showed that matrix multiplication could be done with 49 multiplications (previously thought to require 64). AlphaEvolve found a new algorithm that uses only 48 — improving on more than 50 years of human research.

Discovery 2: new bounds in combinatorics

On problems like tensor decomposition and sorting networks, AlphaEvolve found several new bounds that beat the previously best-known results.

Discovery 3: optimizing Google's own infrastructure

DeepMind used AlphaEvolve internally to optimize:

  • Data-center scheduling algorithms (saving 0.7% of global compute resources)
  • TPU matrix-multiplication hardware design
  • Machine learning kernel optimization

What AlphaEvolve Demonstrates

AlphaEvolve makes three points:

  1. LLMs can do genuine scientific research — not just "answer questions," but "discover new knowledge"
  2. Evolution + LLM is a powerful combination — the LLM supplies intelligence, evolution supplies exploration
  3. Automatic evaluation is the key enabler — this paradigm only works in domains where results can be evaluated automatically

29.4.2 Genie 3 and Generative World Models

Genie 3 (DeepMind, August 2025) is the flagship example of a generative world model.

What Is a World Model?

A world model is a model that predicts environment dynamics:

text
Input: current state s_t + action a_t
Output: next state s_{t+1}

In RL, a world model can substitute for the real environment — the policy trains inside the world model, avoiding costly real-environment interaction.

The Evolution of the Genie Series

Genie 1 (February 2024): learning a world model from video

  • Input: internet video
  • Output: a controllable "game" environment it can generate
  • Key point: there are no explicit action labels — the model learns on its own "what an action is"

Genie 2 (December 2024): a 3D world model

  • Input: a single image
  • Output: an interactive 3D environment it can generate
  • Key point: the environment stays consistent for several minutes

Genie 3 (August 2025): large-scale, controllable, long-horizon

  • Input: a natural-language description
  • Output: a fully controllable, long-horizon 3D environment
  • Key point: usable for training embodied agents

How Genie 3 Is Trained

text
┌───────────────────────────────────────────────────┐
│ Phase 1: Video pretraining                        │
│   - Large amounts of unlabeled video               │
│   - Learn "how the world works"                   │
├───────────────────────────────────────────────────┤
│ Phase 2: Action labeling                           │
│   - Have an LLM label the actions in the video     │
│   - Learn "which action causes which change"       │
├───────────────────────────────────────────────────┤
│ Phase 3: World model training                      │
│   - (s_t, a_t, s_{t+1}) triples                    │
│   - Train a model that predicts s_{t+1}            │
├───────────────────────────────────────────────────┤
│ Phase 4: RL training                                │
│   - The policy trains inside the world model        │
│   - Avoids expensive real-environment interaction   │
└───────────────────────────────────────────────────┘

Applications of Genie 3

Application 1: training embodied agents

A robot learns to walk, grasp, and manipulate objects inside the world model — avoiding trial and error on a real robot, which is expensive and dangerous.

Application 2: game generation

Genie 3 can generate playable games automatically — a player describes the game they want, and Genie 3 generates the complete environment.

Application 3: simulation-based training

High-risk domains such as autonomous driving, industrial control, and medical surgery — train inside the world model, then deploy to the real environment.

Genie 3's Limitations

  • Accuracy: the world model isn't 100% accurate — long-horizon predictions drift
  • Generalization: environments outside the training distribution are hard to simulate
  • Compute cost: inference with a high-quality world model is expensive

29.4.3 Titans and Long-Term Memory Architectures

Titans (Google, published December 2024, revised 2025) opens up a new direction in LLM architecture: long-term memory.

The Motivation Behind Titans

The Transformer has a fundamental limitation: the context window. Even extended to 1M tokens, it still cannot handle "infinitely long" input. Titans tries to solve this problem.

Titans's Design

Titans introduces neural long-term memory:

text
┌────────────────────────────────────────────────────────────────────────────┐
│ Short-term memory: attention (standard Transformer)                        │
│   - Processes the most recent tokens                                       │
│   - Limited capacity (context window)                                      │
├────────────────────────────────────────────────────────────────────────────┤
│ Long-term memory: neural memory module (new)                               │
│   - Continuously learns and stores                                         │
│   - Unlimited capacity                                                     │
├────────────────────────────────────────────────────────────────────────────┤
│ Persistent memory: task-relevant knowledge (system prompt, knowledge base) │
│   - Fixed, does not change                                                 │
└────────────────────────────────────────────────────────────────────────────┘

The three memory tiers together let Titans handle arbitrarily long input — the long-term memory keeps accumulating historical information as the sequence grows.

How Titans Relates to RL

At its core, Titans is about learning how to remember — and that is itself an RL problem:

  • State: the current input plus the current memory
  • Action: how to update the memory (write / forget / update)
  • Reward: future task performance (if the memory stores useful information, task performance improves)

Titans uses surprise as an internal reward signal — memory strengthens when the input is "surprising" and weakens when the input is "repetitive." This is a form of self-supervised RL: the model generates its own reward.

Titans's Experimental Results

On long-horizon tasks, Titans substantially outperforms the Transformer:

TaskTransformerTitans
Language modeling (10M context)OOM67% perplexity improvement
Long-document QA55%78%
Time-series forecasting65%82%

Titans's results argue that long-term memory is the next axis of scaling — not just "wider and deeper," but also "able to remember more."

29.4.4 M-GRPO and Multi-Agent Search Training

Multi-Agent Deep Research: Training Multi-Agent Systems with M-GRPO (ByteDance Seed, November 2025) trains a multi-agent search system with M-GRPO — a multi-agent extension of Group Relative Policy Optimization.

The System Design Behind M-GRPO

The multi-agent system consists of a main agent and several sub-agents:

text
┌────────────────────────────────────────────────────────────┐
│ Main agent (planner): overall planning                     │
│   - Receives the task                                      │
│   - Decomposes it into subtasks                             │
│   - Dispatches sub-agents                                  │
├────────────────────────────────────────────────────────────┤
│ Sub-agents (tool executors): tool execution                │
│   - Call search, code, and other tools over multiple turns │
│   - Call frequency and count vary by sub-agent             │
├────────────────────────────────────────────────────────────┤
│ Hierarchical credit assignment                              │
│   - Main agent and sub-agents each compute group-relative  │
│     advantages                                              │
│   - Exchange minimal statistics through a shared store     │
└────────────────────────────────────────────────────────────┘

How M-GRPO Trains

M-GRPO addresses three difficulties specific to multi-agent RL training:

  • Hierarchical credit assignment: the main agent and the sub-agents each compute their own group-relative advantage, avoiding "credit confusion" between levels
  • Trajectory alignment: because the number of sub-agent calls varies, a trajectory-alignment scheme produces fixed-size batches
  • Decoupled training: agents run on separate servers and exchange statistics through a shared store, so no gradients need to cross servers

On benchmarks such as GAIA, XBench-DeepSearch, and WebWalkerQA, M-GRPO consistently outperforms both single-agent GRPO and multi-agent GRPO with frozen sub-agents.

How M-GRPO Relates to AlphaEvolve

Both combine LLMs with RL or search, but they approach the problem from different angles:

  • AlphaEvolve: evolutionary search (gradient-free, population-based), aimed at algorithm discovery
  • M-GRPO: multi-agent RL (built on GRPO), aimed at tool-augmented deep research

They are two complementary paradigms within LLM-driven discovery.

29.4.5 Recursive Self-Improvement

Recursive Self-Improvement (RSI) is the ultimate form of LLM-driven discovery — the model improves itself.

The Core Loop of RSI

text
┌─────────────────────────────────────────────────────────────────┐
│ 1. Current model M_t evaluates its own capabilities             │
│    - Which tasks does it do well on? Which tasks is it weak on? │
├─────────────────────────────────────────────────────────────────┤
│ 2. Generate an improvement plan                                 │
│    - Design new training data                                   │
│    - Adjust training hyperparameters                            │
│    - Improve the algorithm                                      │
├─────────────────────────────────────────────────────────────────┤
│ 3. Execute the improvement                                      │
│    - Train a new model M_{t+1} using the plan                   │
├─────────────────────────────────────────────────────────────────┤
│ 4. Evaluate the new model                                       │
│    - Is M_{t+1} better than M_t?                                │
│    - If better, keep M_{t+1}; if worse, roll back                │
├─────────────────────────────────────────────────────────────────┤
│ 5. Return to step 1                                              │
└─────────────────────────────────────────────────────────────────┘

Where RSI Stands Today

As of mid-2026, RSI is still a research concept, with no industrial-grade implementation. Three reasons why.

Challenge 1: self-evaluation is unreliable

A model has a hard time accurately judging its own capabilities — it tends to overestimate, a Dunning-Kruger effect for machines.

Challenge 2: the search space of improvement plans explodes

The combinations of possible training data, hyperparameters, and algorithms are astronomical in number.

Challenge 3: safety risk

If a model can improve itself without limit, it could escape human control — this is the central concern in AI safety.

Partial Implementations of RSI

Full RSI doesn't exist yet, but several partial implementations point in that direction:

  • AutoGPT (2023): an early attempt, with limited results
  • SRPO (arXiv:2406.01660): trains a preference model through a self-improvement process (Cohere, 2024)
  • Voyager (arXiv:2305.16291): a Minecraft agent that autonomously learns new skills
  • DeepMind's self-play systems: models that improve by playing against themselves

These are early forms of RSI — they prove partial feasibility, but remain far from true "recursive self-improvement."

29.4.6 The Shared Pattern Across LLM-Driven Discovery

AlphaEvolve, Genie 3, Titans, MIRAS, and RSI share a common pattern.

Traditional search methods (MCTS, beam search) need a hand-designed heuristic. An LLM can generate the heuristic automatically — making the search smarter.

Automatic Evaluation Is the Key Enabler

AlphaEvolve can discover new algorithms precisely because an algorithm's effect can be measured automatically — running the code tells you the answer. This is the precondition for LLM-driven discovery: only domains that support automatic evaluation are a fit.

Combination Beats Any Single Method

  • AlphaEvolve = LLM + evolution
  • Genie 3 = LLM + world model
  • Titans = LLM + long-term memory
  • Multi-Agent Deep Research = LLM + multi-agent + RL

Combining multiple methods outperforms any single method alone — this is what RL looks like in the LLM era.

From "Training a Policy" to "Training a System"

Traditional RL trains a single policy. LLM-driven discovery trains a complete research system — multiple agents plus memory plus search plus tools, working together.

29.4.7 Future Directions

Scientific Discovery

Extending the AlphaEvolve approach to:

  • Biology: protein design, drug discovery
  • Chemistry: new molecular synthesis routes
  • Physics: new experiment design, new theory validation

Education

Using LLM-driven discovery to personalize education — finding the learning path best suited to each individual student.

AGI

Recursive self-improvement is one candidate path to AGI — if a model can keep improving itself, it might at some point surpass human capability.

This comes with serious safety risk, which is also the central topic of alignment research.

Summary

LLM-driven discovery is RL's new frontier for 2025–2026:

  • AlphaEvolve: LLM + evolution, discovering new mathematics
  • Genie 3: a generative world model, used for embodied agents
  • Titans: a long-term memory architecture, extending context
  • M-GRPO: multi-agent RL training
  • RSI: recursive self-improvement (partially realized)

Together, these works point to a new paradigm — training a research system, not just a policy. This is the next-generation direction where RL and LLMs fuse most deeply, and it sits at the very frontier of AGI research.

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