Among the relevant aspects of the family resemblance approach (FRA), our study focuses on the potential of the approach to elaborate on disciplinary identities in an interdisciplinary context, specifically regarding the interplay between physics and mathematics. We present and discuss how the FRA wheel can be used and intertwined with the framework of boundary objects and boundary crossing mechanisms (Akkerman & Bakker, Review of Educational Research, 81, 132–169, 2011), which is well-known in STEM education for dealing with interdisciplinarity. The role of the FRA discussed in the article is dual: both practical and theoretical. It is practical in that we show how its use, in combination with the Akkerman and Bakker framework, appears effective in fostering productive discussions among prospective teachers on disciplinary identities and interdisciplinarity in historical cases. It is theoretical in that the combination of the two frameworks provides the vocabulary to characterise the ‘ambiguous nature’ of interdisciplinarity: like boundaries, interdisciplinarity both separates disciplines, making their identities emerge, and connects them, fostering mechanisms of crossing and transgressing the boundaries. This empirical study reveals how the theoretical elaboration took advantage of the prospective teachers’ contributions. We initially presented the FRA to characterise disciplinary identities, but the prospective teachers highlighted its potential to characterise also the boundary zone and the dialogue between physics and mathematics. The data analysis showed that the combinination of the two frameworks shaped a complex learning space where there was room for very different epistemic demands of the prospective teachers: from those who feel better within the identity cores of the disciplines, to those who like to inhabit the boundary zone and others who like to re-shape boundary spaces and move dynamically across them.

在家族相似性方法 (FRA) 的相关方面，我们的研究侧重于该方法在跨学科背景下阐述学科特性的潜力，特别是关于物理和数学之间的相互作用。我们介绍并讨论如何使用 FRA 轮并将其与边界对象和边界交叉机制的框架交织在一起（Akkerman 和 Bakker，教育研究评论，81, 132–169, 2011)，这在 STEM 教育中以处理跨学科性而闻名。本文中讨论的 FRA 的作用是双重的：既有实际意义，也有理论意义。这是实用的，因为我们展示了它的使用，结合 Akkerman 和 Bakker 框架，似乎有效地促进了未来教师之间关于历史案例中学科身份和跨学科性的富有成效的讨论。理论上，这两个框架的结合提供了描述跨学科性“模糊性质”的词汇：像边界一样，跨学科性既将学科分开，使它们的身份出现，又将它们联系起来，培养跨越和超越边界的机制。这项实证研究揭示了理论阐述如何利用未来教师的贡献。我们最初提出 FRA 是为了描述学科特性，但未来的教师强调了它在描述边界区域和物理与数学之间的对话方面的潜力。数据分析表明，这两个框架的结合形成了一个复杂的学习空间，在这个空间中，未来的教师有非常不同的认知需求：从那些在学科的身份核心中感觉更好的人，到那些喜欢居住在学科中的人。边界区和其他喜欢重塑边界空间并动态移动的人。但未来的教师强调了它在描述边界区域和物理与数学之间的对话方面的潜力。数据分析表明，这两个框架的结合形成了一个复杂的学习空间，在这个空间中，未来的教师有非常不同的认知需求：从那些在学科的身份核心中感觉更好的人，到那些喜欢居住在学科中的人。边界区和其他喜欢重塑边界空间并动态移动的人。但未来的教师强调了它在描述边界区域和物理与数学之间的对话方面的潜力。数据分析表明，这两个框架的结合形成了一个复杂的学习空间，在这个空间中，未来的教师有非常不同的认知需求：从那些在学科的身份核心中感觉更好的人，到那些喜欢居住在学科中的人。边界区和其他喜欢重塑边界空间并动态移动的人。