# Convolutional neural networks: a magic bullet for gravitational-wave detection?

## TL;DR

This paper evaluates convolutional neural networks for gravitational-wave detection, highlighting their potential as rapid trigger generators while discussing limitations, pitfalls, and adversarial vulnerabilities in the context of LIGO data analysis.

## Contribution

It provides a detailed assessment of CNNs for gravitational-wave detection, proposing improved performance metrics and demonstrating their use as fast trigger generators with cautionary insights.

## Key findings

- CNNs can rapidly flag potential gravitational-wave signals.
- The proposed architecture outperforms standard binary classification schemes.
- Adversarial examples reveal significant failure modes of CNN-based detection.

## Abstract

In the last few years, machine learning techniques, in particular convolutional neural networks, have been investigated as a method to replace or complement traditional matched filtering techniques that are used to detect the gravitational-wave signature of merging black holes. However, to date, these methods have not yet been successfully applied to the analysis of long stretches of data recorded by the Advanced LIGO and Virgo gravitational-wave observatories. In this work, we critically examine the use of convolutional neural networks as a tool to search for merging black holes. We identify the strengths and limitations of this approach, highlight some common pitfalls in translating between machine learning and gravitational-wave astronomy, and discuss the interdisciplinary challenges. In particular, we explain in detail why convolutional neural networks alone cannot be used to claim a statistically significant gravitational-wave detection. However, we demonstrate how they can still be used to rapidly flag the times of potential signals in the data for a more detailed follow-up. Our convolutional neural network architecture as well as the proposed performance metrics are better suited for this task than a standard binary classifications scheme. A detailed evaluation of our approach on Advanced LIGO data demonstrates the potential of such systems as trigger generators. Finally, we sound a note of caution by constructing adversarial examples, which showcase interesting "failure modes" of our model, where inputs with no visible resemblance to real gravitational-wave signals are identified as such by the network with high confidence.