Jacob Lurie has extensively developed derived algebraic geometry in the setting of $\mathbb{E}_\infty$-ring spectra [[SAG]](http://www.math.harvard.edu/~lurie/papers/SAG-rootfile.pdf). The resulting theory of Spectral Algebraic Geometry (SAG) gives (in particular) a way to view some of the spectra topologists care about algebro-geometrically, as spectral schemes. In particular, examples of such spectra would be

 1. The complex cobordism spectrum $\mathrm{MU}$; 

 2. Complex $K$-theory $\mathrm{KU}$;

 3. The spectrum $\mathrm{TMF}$ of topological modular forms;

 4. The sphere spectrum $\mathbb{S}$.

On the other hand, there are many important spectra which don't admit $\mathbb{E}_\infty$-structures (and hence don't fit in Lurie's SAG) such as:

 1. The $p$-local Brown-Peterson spectrum $\mathrm{BP}$ and its connective covers $\rm{BP}\langle n\rangle$;

 2. The Morava $K$-theories $K(n)$;

 3. The Ravenel spectra $X(n)$.

There has been work on SAG over $\mathbb{E}_n$-rings, in particular by John Francis, in his [thesis](https://sites.math.northwestern.edu/~jnkf/writ/thezrev.pdf). Focusing on  $n=2$, what results of SAG are expected to be troublesome to extend to the setting of $\mathbb{E}_2$-ring spectra?

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I'm also tempted to ask here Sanath's question on this topic:

> [...] what are some results in either the purely algebro-geometric or purely chromatic aspects of spectral algebraic geometry which rely upon using the entire $\mathbb{E}_\infty$-ring structure?

to be found in his [A love letter to E_2-rings](https://sanathdevalapurkar.github.io/algebraic-topology/2019/06/06/ode.html).

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@crystalline raised two interesting questions in the comments:
> [...] what results of SAG does one actually want in the E_2-setting? and what are some concrete things those results would buy you?