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arXiv · 2012.08533

Bootstrapping traceless symmetric $O(N)$ scalars

Marten Reehorst·Maria Refinetti·Alessandro Vichi
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Abstract

We use numerical bootstrap techniques to study correlation functions of traceless symmetric tensors of $O(N)$ with two indexes $t_{ij}$. We obtain upper bounds on operator dimensions for all the relevant representations and several values of $N$. We discover several families of kinks, which do not correspond to any known model and we discuss possible candidates. We then specialize to the case $N=4$, which has been conjectured to describe a phase transition in the antiferromagnetic real projective model ARP$^{3}$. Lattice simulations provide strong evidence for the existence of a second order phase transition, while an effective field theory approach does not predict any fixed point. We identify a set of assumptions that constrain operator dimensions to a closed region overlapping with the lattice prediction. The region is still present after pushing the numerics in the single correlator case or when considering a mixed system involving $t$ and the lowest dimension scalar singlet.

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Marten Reehorst, Maria Refinetti, Alessandro Vichi. 2020-12-15. Bootstrapping traceless symmetric $O(N)$ scalars. https://doi.org/10.21468/scipostphys.14.4.068

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