A bstract The three tachyon-free non-supersymmetric string theories in ten dimensions
provide a handle on quantum gravity away from the supersymmetric lamppost. However …

In this work we investigate the Swampland Cobordism Conjecture in the context of type IIB
string theory geometries with non-trivial duality bundle. Quite remarkably, we find that many …

We show that the low-energy effective actions of two ten-dimensional supersymmetric
heterotic strings are different by a $\mathbb {Z} _3 $-valued discrete topological term even …

The beginning graduate student in homotopy theory is confronted with a vast literature on
spectra that is scattered across books, articles and decades. There is much folklore but very …

We construct a morphism of spectra from $\mathrm {KO}((q))/\mathrm {TMF} $ to $\Sigma^{-
20} I_ {\mathbb {Z}}\mathrm {TMF} $, which we show to be an equivalence and to implement …

In the presence of a nonzero B-field, the symmetries of the E8× E 8 heterotic string form a 2-
group, or a categorified group, as do the symmetries of the CHL string. We express the …

Using techniques in motivic homotopy theory, especially the theorem of Gheorghe, the
second and the third author on the isomorphism between motivic Adams spectral sequence …

We prove that the element $ h_6^ 2$ is a permanent cycle in the Adams spectral sequence.
As a result, we establish the existence of smooth framed manifolds with Kervaire invariant …

We determine the image of the 2–primary tmf Hurewicz homomorphism, where tmf is the
spectrum of topological modular forms. We do this by lifting elements of tmf⁡∗ to the …

For physicists: For supersymmetric quantum mechanics, there are cases when a mod-2
Witten index can be defined, even when a more ordinary\(\mathbb {Z}\)-valued Witten index …