What is The Physics of Automated Market Makers?
Mathematical Foundation
Laws & Principles
- The Divergence Axiom: Impermanent loss only occurs when the prices of the two tokens diverge relative to each other. If Token A goes up 100% and Token B goes up 100%, the ratio is identical (P=1), and therefore Impermanent Loss is mathematically 0%.
- The Break-Even Yield Law: The only mathematical reason to accept IL risk is if the trading fees (Yield/APY) generated by the liquidity pool exceed the IL drain. If your pool suffers exactly 5.7% Impermanent Loss, but the trading fees paid you 12.0% over the same sequence, the LP position was still highly profitable.
- 'Impermanent' Terminology: The loss is called 'impermanent' because if the tokens perfectly revert exactly back to their initial entry prices, the mathematical loss vanishes instantly. However, if you withdraw your tokens while the prices are diverged, the loss instantly becomes permanently realized.
Step-by-Step Example Walkthrough
" A DeFi yield farmer deposits exactly $500 of ETH and $500 of USDC into a standard 50/50 Liquidity Pool. Total starting value is $1,000. "
- The Shock: The price of ETH violently doubles (+100%). Open market value is up.
- The HODL Value: If the farmer had kept the tokens in their wallet, the USDC is still worth $500, and the ETH doubled to $1,000. True HODL value = $1,500.
- The AMM Rebalance: Inside the pool, arbitrageurs aggressively drained the expensive ETH and dumped cheap USDC to rebalance the 50/50 ratio.
- Calculate the Ratio (P): 2.0 (ETH doubled) / 1.0 (USDC flat) = 2.0. Execute Formula: (2 * sqrt(2)) / (1 + 2) - 1 = 0.9428 - 1 = -0.0572 (-5.72%).