nLab brave new algebra



Stable Homotopy theory

Higher algebra



The term brave new algebra has been coined to refer to the higher algebra of E-infinity rings (“brave new rings”), amplifying the step from more traditional algebra.

Specifically, the term is typically used for the particular presentation of E-infinity rings by way of highly structured ring spectra such as (commutative) monoids with respect to a symmetric monoidal smash product of spectra (such as available on orthogonal spectra (orthogonal ring spectra), symmetric spectra (symmetric ring spectra) and S-modules).

According to Greenlees 06, p. 1:

The phrase ‘brave new rings’ was coined by F.Waldhausen, presumably to capture both an optimism about the possibilities of generalizing rings to ring spectra, and a proper awareness of the risk that the new step in abstraction would take the subject dangerously far from its justification in examples.

In consequence people also speak for instance of brave new Hopf algebroids when referring to the Hopf algebroids of (dual) EE-Steenrod algebras for some ring spectrum EE as appearing in the Adams spectral sequence. See at Steenrod algebra – Hopf algebroid structure.


Introductions and expositions include

Monographs on the technical core of “brave new algebra” in terms of symmetric monoidal categories of spectra include

For more references see at ring spectrum and at higher algebra.

Last revised on October 24, 2022 at 05:46:28. See the history of this page for a list of all contributions to it.