Gabriel Luz Almeida 博士系列学术报告

Title: Advanced Lectures on Quantum Field Theory: NRGR - The PN-EFT for Compact Binaries

Speaker: Gabriel Luz Almeida

Affiliation: Shing-Tung Yau center, Southeast University(东南大学丘成桐中心)

Time: 13:00 - 13:50, Tuesday, 27th January, 2026

             14:00 - 14:50, Tuesday, 27th January, 2026  

             13:00 - 13:50, Wednesday, 28th January, 2026

             14:00 - 14:50, Wednesday, 28th January, 2026

    (UTC+8, Beijing Time)

Venue: Room 1502, Shing-Tung Yau Center, Yifu Architecture Building, Sipailou Campus of Southeast University, Nanjing (东南大学四牌楼校区逸夫建筑馆丘成桐中心1502室)

Lecture Introduction

The detection of gravitational waves from coalescing compact binaries by the LIGO and Virgo interferometers has revived interest in the relativistic two-body problem. These observations have profoundly advanced our understanding of both astrophysical and cosmological processes. In the mid-2000s, this field was significantly transformed by the recasting of binary dynamics into a systematic field-theoretical framework using Effective Field Theory (EFT) techniques.

Within this EFT framework, the inherent hierarchical scales of the problem delineate distinct dynamical regions. The short-distance scale governs the conservative orbital interaction via potential modes (the near zone), while the long-distance scale describes the emission and propagation of gravitational radiation (the far or radiation zone).

In this mini-course, I will present the general formulation of the EFT for compact binary systems. We will begin with foundational concepts in gravitational wave theory and EFT construction, before applying this methodology to gravitationally bound systems. The core of the lectures will focus on Non-Relativistic General Relativity (NRGR), the specific EFT that provides a rigorous power-counting framework for the post-Newtonian approximation in binary dynamics.

● Tue, January 27, 2026

1:00PM → 1:50PM

Lecture 1: A brief introduction to GWs and EFTs

This lecture will cover two foundational topics: the basics of gravitational waves, from linearized theory to the waveforms of coalescing binaries; and the core principles of Effective Field Theory construction using the Wilsonian approach to renormalization and the method of regions.

2:00PM → 2:50PM

Lecture 2: The EFT for compact binary systems

This lecture will introduce the multi-scale structure of the two-body problem in GR and its formulation as an EFT. We will define the dynamical regions and introduce NRGR as the EFT framework that systematically separates these scales.

◆ Wed, January 28, 2026

1:00PM → 1:50PM

Lecture 3: The far (or radiation) zone

This lecture covers the far zone, the crucial matching procedure, and the computation of observables—including the energy-momentum tensor and the radiated energy flux—highlighting the use of the optical theorem, connecting self-energy diagrams to emission amplitudes.

2:00PM → 2:50PM

Lecture 4: Radiative processes

We conclude the course by examining subtle, non-linear effects in gravitational-wave propagation—the tail and tails-of-tails phenomena. The lecture will demonstrate how the EFT's renormalization procedure for multipole moments provides a unified treatment of the resulting infrared and ultraviolet divergences.