The aftermath of the 2020 US Presidential Election witnessed an unprecedented attack on the democratic values of the country through the violent insurrection at Capitol Hill on January 6th, 2021. The attack was fueled by the proliferation of conspiracy theories and misleading claims about the integrity of the election pushed by political elites and fringe communities on social media. In this study, we explore the evolution of fringe content and conspiracy theories on Twitter in the seven months leading up to the Capitol attack. We examine the suspicious coordinated activity carried out by users sharing fringe content, finding evidence of common adversarial manipulation techniques ranging from targeted amplification to manufactured consensus. Further, we map out the temporal evolution of, and the relationship between, fringe and conspiracy theories, which eventually coalesced into the rhetoric of a stolen election, with the hashtag #stopthesteal, alongside QAnon-related narratives. Our findings further highlight how social media platforms offer fertile ground for the widespread proliferation of conspiracies during major societal events, which can potentially lead to offline coordinated actions and organized violence.

翻译：2020年美国总统大选后，2021年1月6日国会山发生的暴力叛乱对美国民主价值观造成了前所未有的冲击。此次袭击受到政治精英和社交媒体边缘社群推动的阴谋论及关于选举公正性的误导性言论的助长。本研究探究了国会大厦袭击前七个月间，Twitter上边缘内容和阴谋论的演变过程。我们分析了分享边缘内容的用户所进行的可疑协同活动，发现了从定向放大到制造共识等常见对抗性操纵技术的证据。进一步地，我们描绘了边缘理论与阴谋论在时间上的演化轨迹及其相互关系——这些内容最终汇聚成"选举被窃取"的论调，表现为#stopthesteal话题标签与QAnon相关叙事的交织。研究结果进一步揭示了：社交媒体平台如何为重大社会事件期间阴谋论的广泛传播提供温床，进而可能引发线下协同行动与有组织的暴力行为。