Scaling LLMs Part 4: How Q* by OpenAI works and why it dramatically accelerates the push toward AGI

Welcome to our exploration of Q*, a groundbreaking development in AI, particularly in scaling Large Language Models (LLMs).

In short, Q* makes LLMs PONDER.

1. What Q* Represents:

Q* stands for a new technique that leverages reinforcement learning (RL), akin to MuZero-style RL by Google DeepMind, to enhance LLMs' capabilities. It's an approach where the model learns optimal behaviors through a process similar to trial and error.

2. How Q* Works:

Q* adopts MuZero-style RL, using Monte Carlo Tree Search (MCTS) combined with a reward function learning mechanism. This allows Q* to simulate a vast array of potential actions (predictions of tokens) and learn from the best outcomes, greatly improving its decision-making process in multiple steps.

For example, a LLM can predict each token 100 times and then learn which sequence of tokens ultimately leads to the best outcome (the highest reward).

3. Mathematics as a String Manipulation Game:

In the realm of formal mathematics, systems like ZFC are built on "starting strings" (axioms), "string generators" (axiom schema), and "string manipulation rules" (laws of inference).

The goal is to use these rules on starting strings or strings generated from templates to produce a target string, known as a theorem.

This framework aligns well with how Q* approaches mathematical problem-solving, treating math as a game of string manipulations.

4. Q* and Mathematical Problem Solving:

Q* generates a 'tree of thoughts' by predicting the next tokens multiple times, akin to exploring different branches in MCTS. Each branch represents a potential solution path, and the model learns to effectively navigate this tree with the feedback on the correctness of each solution.

5. Trading Off Inference Time for Quality:

Q* trades increased inference time for enhanced quality of outcomes. By spending more time analyzing each decision (e.g. predicting the next token 100x), Q* achieves a level of inference quality that rivals much larger models.

6. Small Model, Big Impact:

This strategy enables a smaller model to deliver the performance of a significantly larger one. It's an efficient way to scale up the capabilities of LLMs without proportionally increasing their model size, data size and compute.

7. Overcoming Data Scarcity with Synthetic Data:

Intriguingly, Q*'s approach of learning from its best predictions is akin to training with self-generated synthetic data. This method effectively addresses one of the major challenges in scaling LLMs: data scarcity.

By generating and learning from its own predictions, Q* paves the way for more efficient and scalable AI models, marking a new era in AI research and applications.