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W. Zhan
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Is there a definition of reduced $E_\infty$ ring?

I am curious if there is well defined notion of reduced $E_\infty$-ring.

Let $CAlg$ denote the $\infty$-categoory of $E_\infty$-ring, $CAlg_1$, the one category of communicative rings. I would like to define the analog for reduced ring.

One categorically, $ CAlg_1^{red} \hookrightarrow CAlg_1$ admits a left adjoint $A \mapsto A^{red}:=A /nil(A)$.


We can define $$CAlg^{red} \hookrightarrow CAlg$$ as the $\infty$-cat. of $E_\infty$-rings whose underling ring is reduced.

Question: Does there exist a left adjoint? What about when we restrict to connective $E_\infty$-rings?


It seems too me that the approoach in HA,7.2.3 is somewhat relevant. I'd like to know if this this question is addressed somewhere in the literature.

W. Zhan
  • 448
  • 2
  • 8