The exchange of knowledge across different areas and disciplines plays a key role in the process of knowledge creation, and can stimulate innovation and the emergence of new fields. We develop here a quantitative framework to extract significant dependencies among scientific disciplines and turn them into a time-varying network whose nodes are the different fields, while the weighted links represent the flow of knowledge from one field to another at a given period of time. Drawing on a comprehensive data set on scientific production in modern physics and on the patterns of citations between articles published in the various fields in the last thirty years, we are then able to map, over time, how the ideas developed in a given field in a certain time period have influenced later discoveries in the same field or in other fields. The analysis of knowledge flows internal to each field displays a remarkable variety of temporal behaviours, with some fields of physics showing to be more self-referential than others. The temporal networks of knowledge exchanges across fields reveal cases of one field continuously absorbing knowledge from another field in the entire observed period, pairs of fields mutually influencing each other, but also cases of evolution from absorbing to mutual or even to back-nurture behaviors.

中文翻译：

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现代物理学领域内和跨领域的知识演变

不同领域和学科之间的知识交流在知识创造过程中起着关键作用，可以刺激创新和新领域的出现。我们在这里开发了一个量化框架来提取科学学科之间的重要依赖关系，并将它们变成一个时变网络，其节点是不同的领域，而加权链接代表在给定时间段内从一个领域到另一个领域的知识流。利用现代物理学科学成果的综合数据集以及过去三十年在各个领域发表的文章之间的引用模式，我们能够随着时间的推移绘制出特定领域的思想如何发展的图。某个时期影响了后来在同一领域或其他领域的发现。对每个领域内部知识流的分析显示出显着多样的时间行为，物理的某些领域表现出比其他领域更多的自我参照。跨领域知识交流的时间网络揭示了一个领域在整个观察期内不断从另一个领域吸收知识的案例，成对的领域相互影响，以及从吸收到相互甚至回养行为的演变案例。