An agent is an autonomous entity that perceives its environment and takes actions to achieve goals, often used in reinforcement learning.An agent is an autonomous entity that perceives its environment and takes actions to achieve goals. In physics and related fields, agents are often computational systems that interact with simulations or experiments, making decisions based on data to optimize outcomes. They are central to reinforcement learning, where an agent learns a policy by trial and error, receiving rewards or penalties for its actions.
The concept of an agent in artificial intelligence emerged in the 1980s, with reinforcement learning formalized by Richard Sutton and Andrew Barto in their 1998 book. The term 'agent' itself has roots in philosophy and economics, but its computational use became prominent in the 1990s.
The agent operates in a loop: it observes the current state of its environment, selects an action based on its policy, and receives a reward and a new state. Over time, it updates its policy to maximize cumulative reward. In physics applications, the environment might be a quantum system, a material simulation, or a cosmological dataset, and the agent's actions could be parameter adjustments, measurement choices, or experimental designs.
Agents are used in physics to autonomously control experiments, optimize quantum circuits, discover new materials, and analyze large datasets, as seen in the provided titles about AI-driven physical analysis and material design.
In some quantum experiments, agents have been trained to create and maintain entanglement, effectively 'learning' to control quantum chaos.




















