# The origin of Galactic cosmic rays: challenges to the standard paradigm

## TL;DR

This paper critically reviews the standard paradigm of Galactic cosmic ray origins, highlighting recent unexpected observations that challenge current understanding and discussing whether paradigm modifications are necessary.

## Contribution

It provides a comprehensive analysis of recent cosmic ray data and open issues, questioning the adequacy of the standard paradigm and exploring potential paradigm shifts.

## Key findings

- Recent measurements reveal unexpected cosmic ray behaviors.
- Current understanding of cosmic ray origins remains incomplete.
- Open issues challenge the standard paradigm.

## Abstract

A critical review of the standard paradigm for the origin of Galactic cosmic rays is presented. Recent measurements of local and far-away cosmic rays reveal unexpected behaviours, which challenge the commonly accepted scenario. These recent findings are discussed, together with long-standing open issues. Despite the progress made thanks to ever-improving observational techniques and theoretical investigations, at present our understanding of the origin and of the behaviour of cosmic rays remains incomplete. We believe it is still unclear whether a modification of the standard paradigm, or rather a radical change of the paradigm itself is needed in order to interpret all the available data on cosmic rays within a self-consistent scenario.