25. Research Frontiers

25. Research Frontiers

Overview

This lesson explores the cutting edge of Foundation Model research. We investigate future directions including World Models, o1-style Reasoning, Synthetic Data, and Multi-Agent systems.


1. o1-style Reasoning (Test-time Compute)

1.1 Concept

Traditional LLM vs o1-style:
┌─────────────────────────────────────────────────────────┐
  Traditional LLM:                                       
  - Focus computation at training time                   
    (larger models, more data)                          
  - Fixed forward pass during inference                  
  - Limitations on complex problems                      
                                                         
  o1-style (Test-time Compute Scaling):                 
  - Use more computation during inference                
  - Automatic Chain-of-Thought generation               
  - Explore multiple paths, select best                  
  - Adaptive computation based on problem difficulty    
└─────────────────────────────────────────────────────────┘

Key Techniques:
1. Internal Chain-of-Thought
2. Search/Verification loops
3. Self-consistency checking
4. Reward model guided search

1.2 Conceptual Implementation

import torch
from typing import List, Tuple

class ReasoningModel:
    """o1-style reasoning model (conceptual implementation)"""

    def __init__(self, base_model, reward_model):
        self.model = base_model
        self.reward_model = reward_model

    def reason(
        self,
        problem: str,
        max_thinking_tokens: int = 10000,
        num_candidates: int = 5
    ) -> str:
        """Extended reasoning"""
        # 1. Generate multiple reasoning chains
        candidates = self._generate_candidates(problem, num_candidates)

        # 2. Evaluate each chain
        scored_candidates = []
        for chain, answer in candidates:
            score = self._evaluate_chain(chain, answer)
            scored_candidates.append((chain, answer, score))

        # 3. Select best answer
        best = max(scored_candidates, key=lambda x: x[2])
        return best[1]  # Return only answer (chain is internal)

    def _generate_candidates(
        self,
        problem: str,
        n: int
    ) -> List[Tuple[str, str]]:
        """Generate multiple reasoning paths"""
        candidates = []

        for _ in range(n):
            # Generate step-by-step reasoning
            chain = self._generate_reasoning_chain(problem)

            # Extract final answer from chain
            answer = self._extract_answer(chain)

            candidates.append((chain, answer))

        return candidates

    def _generate_reasoning_chain(self, problem: str) -> str:
        """Generate reasoning chain"""
        prompt = f"""Solve this problem step by step.
Think carefully and show your reasoning.

Problem: {problem}

Let me think through this carefully..."""

        # Generate without length limit (or very long limit)
        response = self.model.generate(
            prompt,
            max_new_tokens=5000,
            temperature=0.7
        )

        return response

    def _evaluate_chain(self, chain: str, answer: str) -> float:
        """Evaluate reasoning chain quality"""
        # Evaluate with reward model
        score = self.reward_model.evaluate(chain)

        # Self-consistency check
        consistency_score = self._check_consistency(chain, answer)

        return score * 0.7 + consistency_score * 0.3

    def _check_consistency(self, chain: str, answer: str) -> float:
        """Check logical consistency"""
        # Simple heuristic or separate model
        prompt = f"""Is this reasoning chain logically consistent?

Reasoning:
{chain}

Answer: {answer}

Rate consistency (0-1):"""

        response = self.model.generate(prompt, max_new_tokens=10)
        # Parse...
        return 0.8  # Example


class TreeOfThoughts:
    """Tree of Thoughts implementation"""

    def __init__(self, model, evaluator):
        self.model = model
        self.evaluator = evaluator

    def solve(
        self,
        problem: str,
        depth: int = 3,
        branching_factor: int = 3
    ) -> str:
        """Solve with tree search"""
        root = {"state": problem, "thoughts": [], "score": 0}
        best_path = self._search(root, depth, branching_factor)
        return self._extract_solution(best_path)

    def _search(self, node: dict, depth: int, bf: int) -> List[dict]:
        """BFS/DFS search"""
        if depth == 0:
            return [node]

        # Generate next step thoughts
        thoughts = self._generate_thoughts(node, bf)

        # Evaluate each thought
        children = []
        for thought in thoughts:
            child = {
                "state": node["state"],
                "thoughts": node["thoughts"] + [thought],
                "score": self._evaluate_thought(thought, node)
            }
            children.append(child)

        # Expand only top b (beam search)
        children.sort(key=lambda x: x["score"], reverse=True)
        children = children[:bf]

        # Recursive search
        best_paths = []
        for child in children:
            path = self._search(child, depth - 1, bf)
            best_paths.extend(path)

        return sorted(best_paths, key=lambda x: x["score"], reverse=True)[:1]

    def _generate_thoughts(self, node: dict, n: int) -> List[str]:
        """Generate next step thoughts"""
        context = "\n".join(node["thoughts"])

        prompt = f"""Problem: {node["state"]}

Previous thoughts:
{context}

Generate {n} different next steps or approaches:"""

        response = self.model.generate(prompt)
        # Parse to extract n thoughts
        return response.split("\n")[:n]

    def _evaluate_thought(self, thought: str, node: dict) -> float:
        """Evaluate thought quality"""
        return self.evaluator.score(thought, node["state"])

2. Synthetic Data

2.1 Concept

Synthetic Data Generation:
┌─────────────────────────────────────────────────────────┐
  Problem: Shortage of high-quality training data        
                                                         
  Solution: Generate training data with LLMs             
                                                         
  Methods:                                               
  1. Self-Instruct: Generate instruction/response pairs  
  2. Evol-Instruct: Progressive complexity increase      
  3. Rejection Sampling: Generate many, filter best      
  4. RLHF-style: Generate preference data               
  5. Distillation: Strong model to weak model           
                                                         
  Cautions:                                              
  - Model collapse (training only on own data)           
  - Maintain diversity                                   
  - Quality verification essential                       
└─────────────────────────────────────────────────────────┘

2.2 Implementation

class SyntheticDataGenerator:
    """Synthetic data generator"""

    def __init__(self, teacher_model, student_model=None):
        self.teacher = teacher_model
        self.student = student_model

    def generate_instruction_data(
        self,
        seed_instructions: List[str],
        num_samples: int = 10000,
        diversity_threshold: float = 0.7
    ) -> List[dict]:
        """Generate Instruction-Response data"""
        generated = []
        instruction_embeddings = []

        while len(generated) < num_samples:
            # Generate new instruction
            instruction = self._generate_instruction(seed_instructions + [
                g["instruction"] for g in generated[-10:]
            ])

            # Check diversity
            if self._check_diversity(instruction, instruction_embeddings, diversity_threshold):
                # Generate response
                response = self._generate_response(instruction)

                # Quality check
                if self._quality_check(instruction, response):
                    generated.append({
                        "instruction": instruction,
                        "response": response
                    })

                    # Save embedding
                    emb = self._get_embedding(instruction)
                    instruction_embeddings.append(emb)

            if len(generated) % 100 == 0:
                print(f"Generated {len(generated)}/{num_samples}")

        return generated

    def _generate_instruction(self, examples: List[str]) -> str:
        """Generate new instruction"""
        examples_text = "\n".join([f"- {ex}" for ex in examples[-5:]])

        prompt = f"""Here are some example instructions:
{examples_text}

Generate a new, different instruction that is:
1. Clear and specific
2. Different from the examples
3. Useful and educational

New instruction:"""

        return self.teacher.generate(prompt, temperature=0.9)

    def _generate_response(self, instruction: str) -> str:
        """Generate response"""
        prompt = f"""Instruction: {instruction}

Please provide a helpful, accurate, and detailed response:"""

        return self.teacher.generate(prompt, temperature=0.7)

    def _check_diversity(
        self,
        instruction: str,
        existing_embeddings: List,
        threshold: float
    ) -> bool:
        """Diversity check"""
        if not existing_embeddings:
            return True

        new_emb = self._get_embedding(instruction)

        for emb in existing_embeddings:
            similarity = self._cosine_similarity(new_emb, emb)
            if similarity > threshold:
                return False

        return True

    def _quality_check(self, instruction: str, response: str) -> bool:
        """Quality check"""
        # Length check
        if len(response) < 50:
            return False

        # Relevance check (simple heuristic)
        instruction_words = set(instruction.lower().split())
        response_words = set(response.lower().split())

        overlap = len(instruction_words & response_words)
        if overlap < 2:
            return False

        return True


class RejectSampling:
    """Select high-quality data with Rejection Sampling"""

    def __init__(self, generator_model, reward_model):
        self.generator = generator_model
        self.reward = reward_model

    def generate_with_rejection(
        self,
        prompt: str,
        n_samples: int = 16,
        top_k: int = 1
    ) -> List[str]:
        """Generate many, select best"""
        # Generate multiple responses
        responses = []
        for _ in range(n_samples):
            response = self.generator.generate(prompt, temperature=0.8)
            responses.append(response)

        # Score each response
        scored = []
        for response in responses:
            score = self.reward.score(prompt, response)
            scored.append((response, score))

        # Select top k
        scored.sort(key=lambda x: x[1], reverse=True)
        return [r for r, s in scored[:top_k]]

3. Multi-Agent Systems

3.1 Concept

Multi-Agent LLM Systems:
┌─────────────────────────────────────────────────────────┐
│  Agent Types:                                           │
│                                                         │
│  1. Debate: Multiple agents discuss                     │
│     - Present different perspectives                    │
│     - Reach consensus                                   │
│                                                         │
│  2. Collaboration: Role-based cooperation               │
│     - Writer, Reviewer, Editor                          │
│     - Researcher, Developer, Tester                     │
│                                                         │
│  3. Competition: Competitive generation                 │
│     - Select best result                                │
│     - Red team / Blue team                              │
│                                                         │
│  4. Hierarchical: Hierarchical structure                │
│     - Manager → Worker agents                           │
│     - Task decomposition and delegation                 │
└─────────────────────────────────────────────────────────┘

3.2 Implementation

from typing import Dict, Any
from dataclasses import dataclass
from enum import Enum

class AgentRole(Enum):
    PLANNER = "planner"
    RESEARCHER = "researcher"
    WRITER = "writer"
    CRITIC = "critic"
    EDITOR = "editor"

@dataclass
class Message:
    sender: str
    receiver: str
    content: str
    metadata: Dict[str, Any] = None

class MultiAgentSystem:
    """Multi-agent system"""

    def __init__(self, llm):
        self.llm = llm
        self.agents = {}
        self.message_history = []

    def add_agent(self, name: str, role: AgentRole, system_prompt: str):
        """Add agent"""
        self.agents[name] = {
            "role": role,
            "system_prompt": system_prompt,
            "memory": []
        }

    def send_message(self, sender: str, receiver: str, content: str):
        """Send message"""
        message = Message(sender=sender, receiver=receiver, content=content)
        self.message_history.append(message)
        self.agents[receiver]["memory"].append(message)

        return self._get_response(receiver)

    def _get_response(self, agent_name: str) -> str:
        """Generate agent response"""
        agent = self.agents[agent_name]

        # Compose context from recent messages
        recent_messages = agent["memory"][-5:]
        context = "\n".join([
            f"{m.sender}: {m.content}" for m in recent_messages
        ])

        prompt = f"""{agent["system_prompt"]}

Recent conversation:
{context}

Your response as {agent_name}:"""

        return self.llm.generate(prompt)

    def run_debate(
        self,
        topic: str,
        agents: List[str],
        rounds: int = 3
    ) -> str:
        """Run debate"""
        # Initial opinions
        opinions = {}
        for agent in agents:
            response = self.send_message(
                "moderator", agent,
                f"What is your position on: {topic}"
            )
            opinions[agent] = response

        # Debate rounds
        for round in range(rounds):
            for agent in agents:
                # Share other agents' opinions
                other_opinions = "\n".join([
                    f"{a}: {o}" for a, o in opinions.items() if a != agent
                ])

                response = self.send_message(
                    "moderator", agent,
                    f"Others' opinions:\n{other_opinions}\n\nYour response:"
                )
                opinions[agent] = response

        # Reach consensus
        final_opinions = "\n".join([f"{a}: {o}" for a, o in opinions.items()])
        consensus = self.llm.generate(
            f"Based on this debate, summarize the consensus:\n{final_opinions}"
        )

        return consensus


class CollaborativeWriting:
    """Collaborative writing system"""

    def __init__(self, llm):
        self.system = MultiAgentSystem(llm)

        # Setup agents
        self.system.add_agent(
            "writer",
            AgentRole.WRITER,
            "You are a creative writer. Write engaging content."
        )
        self.system.add_agent(
            "critic",
            AgentRole.CRITIC,
            "You are a critical reviewer. Point out issues and suggest improvements."
        )
        self.system.add_agent(
            "editor",
            AgentRole.EDITOR,
            "You are an editor. Refine and polish the writing."
        )

    def write(self, topic: str, iterations: int = 3) -> str:
        """Collaborative writing"""
        # Draft
        draft = self.system.send_message(
            "user", "writer",
            f"Write a short article about: {topic}"
        )

        for i in range(iterations):
            # Critique
            critique = self.system.send_message(
                "writer", "critic",
                f"Please review this draft:\n{draft}"
            )

            # Revise
            revised = self.system.send_message(
                "critic", "writer",
                f"Based on this feedback:\n{critique}\n\nPlease revise the draft."
            )

            draft = revised

        # Final editing
        final = self.system.send_message(
            "writer", "editor",
            f"Please polish this final draft:\n{draft}"
        )

        return final

4. World Models

4.1 Concept

World Models:
┌─────────────────────────────────────────────────────────┐
│  Goal: LLMs understand and simulate how the world works │
│                                                         │
│  Applications:                                          │
│  1. Planning: Predict consequences of actions           │
│  2. Reasoning: Causal relationship inference            │
│  3. Simulation: Virtual environment simulation          │
│  4. Embodied AI: Robot control                          │
│                                                         │
│  Research Directions:                                   │
│  - Video generation as world simulation (Sora)          │
│  - Physical reasoning benchmarks                        │
│  - Embodied language models                             │
│  - Causal reasoning                                     │
└─────────────────────────────────────────────────────────┘

4.2 Conceptual Implementation

class WorldModel:
    """World Model conceptual implementation"""

    def __init__(self, llm):
        self.llm = llm
        self.state = {}

    def initialize_state(self, description: str):
        """Set initial state"""
        prompt = f"""Parse this scene description into structured state.

Description: {description}

Extract:
- Objects (name, position, properties)
- Relationships between objects
- Physical constraints

State:"""

        state_text = self.llm.generate(prompt)
        self.state = self._parse_state(state_text)

    def predict_action_result(self, action: str) -> Dict:
        """Predict action result"""
        state_description = self._describe_state()

        prompt = f"""Current state:
{state_description}

Action: {action}

Predict:
1. What changes will occur?
2. What is the new state?
3. Any unexpected effects?

Prediction:"""

        prediction = self.llm.generate(prompt)
        return self._parse_prediction(prediction)

    def simulate_sequence(
        self,
        actions: List[str]
    ) -> List[Dict]:
        """Simulate action sequence"""
        states = [self.state.copy()]

        for action in actions:
            prediction = self.predict_action_result(action)
            self._apply_changes(prediction)
            states.append(self.state.copy())

        return states

    def _describe_state(self) -> str:
        """Describe state as text"""
        # Convert state dict to natural language
        return str(self.state)

    def _parse_state(self, text: str) -> Dict:
        """Parse text to state"""
        # More sophisticated parsing needed in practice
        return {"raw": text}

    def _parse_prediction(self, text: str) -> Dict:
        """Parse prediction result"""
        return {"raw": text}

    def _apply_changes(self, prediction: Dict):
        """Apply predicted changes"""
        # Update state
        pass

5. Future Research Directions

5.1 Key Directions

1. Scaling Laws Beyond Parameters
   - Test-time compute scaling
   - Mixture of Experts scaling
   - Data quality over quantity

2. Multimodal Understanding
   - Native multimodal models
   - Embodied AI
   - Physical world understanding

3. Reasoning Enhancement
   - Formal verification
   - Neuro-symbolic integration
   - Causal reasoning

4. Alignment & Safety
   - Constitutional AI
   - Interpretability
   - Robustness to adversarial inputs

5. Efficiency
   - Sparse architectures
   - Mixture of Depths
   - Early exit mechanisms

5.2 Open Problems

┌─────────────────────────────────────────────────────────┐
│  Open Research Problems:                                │
│                                                         │
│  1. Complete Hallucination Resolution                   │
│     - Knowing when you don't know                       │
│     - Confidence calibration                            │
│                                                         │
│  2. True Reasoning vs Pattern Matching                  │
│     - True generalization ability?                      │
│     - Out-of-distribution reasoning                     │
│                                                         │
│  3. Long-term Memory                                    │
│     - Permanent learning                                │
│     - Continual learning without forgetting             │
│                                                         │
│  4. Efficiency-Capability Tradeoff                      │
│     - Limitations of small models?                      │
│     - Knowledge distillation limits                     │
│                                                         │
│  5. Alignment                                           │
│     - Definition of value alignment                     │
│     - Scalable oversight                                │
└─────────────────────────────────────────────────────────┘

Key Summary

Research Frontiers Summary

1. o1-style: More computation at inference time
2. Synthetic Data: Generate training data with LLMs
3. Multi-Agent: Collaboration/debate/competition systems
4. World Models: Physical world simulation
5. Alignment: Safe and useful AI

Future Outlook

- Parameter scaling → Compute scaling
- Single model → Multi-agent systems
- Text → Native multimodal
- Pattern matching → True reasoning
- Black box → Interpretable

References

  1. OpenAI (2024). "Learning to Reason with LLMs" (o1)
  2. Yao et al. (2023). "Tree of Thoughts: Deliberate Problem Solving with Large Language Models"
  3. Park et al. (2023). "Generative Agents: Interactive Simulacra of Human Behavior"
  4. Ha & Schmidhuber (2018). "World Models"
  5. Sora Technical Report (2024)
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