English

Loss-Versus-Rebalancing under Deterministic and Generalized block-times

Mathematical Finance 2025-05-16 v3 Probability Portfolio Management Pricing of Securities Trading and Market Microstructure

Abstract

Although modern blockchains almost universally produce blocks at fixed intervals, existing models still lack an analytical formula for the loss-versus-rebalancing (LVR) incurred by Automated Market Makers (AMMs) liquidity providers in this setting. Leveraging tools from random walk theory, we derive the following closed-form approximation for the per block per unit of liquidity expected LVR under constant block time: ARB=σb22+2πγ/(ζ(1/2)σb)+O ⁣(econstγσb)    σb22+1.7164γ/σb, \overline{\mathrm{ARB}}= \frac{\,\sigma_b^{2}} {\,2+\sqrt{2\pi}\,\gamma/(|\zeta(1/2)|\,\sigma_b)\,}+O\!\bigl(e^{-\mathrm{const}\tfrac{\gamma}{\sigma_b}}\bigr)\;\approx\; \frac{\sigma_b^{2}}{\,2 + 1.7164\,\gamma/\sigma_b}, where σb\sigma_b is the intra-block asset volatility, γ\gamma the AMM spread and ζ\zeta the Riemann Zeta function. Our large Monte Carlo simulations show that this formula is in fact quasi-exact across practical parameter ranges. Extending our analysis to arbitrary block-time distributions as well, we demonstrate both that--under every admissible inter-block law--the probability that a block carries an arbitrage trade converges to a universal limit, and that only constant block spacing attains the asymptotically minimal LVR. This shows that constant block intervals provide the best possible protection against arbitrage for liquidity providers.

Keywords

Cite

@article{arxiv.2505.05113,
  title  = {Loss-Versus-Rebalancing under Deterministic and Generalized block-times},
  author = {Alex Nezlobin and Martin Tassy},
  journal= {arXiv preprint arXiv:2505.05113},
  year   = {2025}
}

Comments

16 pages, 2 figures

R2 v1 2026-06-28T23:25:35.343Z