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Covariant Growth Dynamics

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Handbook of Quantum Gravity

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Abstract

The spacetime discreteness of causal set theory has enabled the formulation of novel spacetime dynamics. In these so-called “growth” dynamics, a causal set spacetime is generated probabilistically by means of a random walk on certain tree structures. The first growth dynamics – the classical sequential growth models – were proposed more than two decades ago, and their study has furthered our understanding of general covariance and covariant observables within causal set theory. In this setting, labels take the place of spacetime coordinates so that general covariance takes the form of label invariance and covariant observables are those order-theoretic properties of the causal set which are label-independent. In recent years, these insights have led to a new formulation of growth dynamics which makes no reference to labels. Here, we present an overview of these (manifestly) covariant growth dynamics.

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Author information

Authors and Affiliations

  1. Blackett Laboratory, Imperial College, London, UK

    Stav Zalel

Authors
  1. Stav Zalel
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Correspondence to Stav Zalel .

Editor information

Editors and Affiliations

  1. Department of Physics, Fudan University, Shanghai, China

    Cosimo Bambi

  2. Department of Physics, Southern University of Science and Techn, Shenzhen, China

    Leonardo Modesto

  3. Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil

    Ilya Shapiro

Section Editor information

  1. Perimeter Institute for Theoretical Physics, Waterloo, Canada

    Rafael D. Sorkin

  2. Raman Research Institute, Bengaluru, India

    Sumati Surya

  3. Department of Physics, Imperial College, London, UK

    Fay Dowker

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Zalel, S. (2024). Covariant Growth Dynamics. In: Bambi, C., Modesto, L., Shapiro, I. (eds) Handbook of Quantum Gravity. Springer, Singapore. https://doi.org/10.1007/978-981-19-3079-9_82-1

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  • DOI: https://doi.org/10.1007/978-981-19-3079-9_82-1

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  • Print ISBN: 978-981-19-3079-9

  • Online ISBN: 978-981-19-3079-9

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