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This paper proposes a connection between algebraic K-theory and foam cobordisms, where foams are stratified manifolds with singularities of a prescribed form. We consider $n$-dimensional foams equipped with a flat bundle of finitely-generated projective $R$-modules over each facet of the foam, together with gluing conditions along the subfoam of singular points. In a suitable sense which will become clear, a vertex (or the smallest stratum) of an $n$-dimensional foam replaces an $(n+1)$-simplex with a total ordering of vertices. We show that the first K-theory group of a ring $R$ can be identified with the cobordism group of decorated 1-foams embedded in the plane. A similar relation between the $n$-th algebraic K-theory group of a ring $R$ and the cobordism group of decorated $n$-foams embedded in $\mathbb{R}^{n+1}$ is expected for $n>1$. An analogous correspondence is proposed for arbitrary exact categories. Modifying the embedding and other conditions on the foams may lead to new flavors of K-theory groups., Comment: 57 pages, many figures

We consider a deformation of the Robert-Wagner foam evaluation formula, with an eye toward a relation to formal groups. Integrality of the deformed evaluation is established, giving rise to state spaces for planar GL(N) MOY graphs (Murakami-Ohtsuki-Yamada graphs). Skein relations for the deformation are worked out in details in the GL(2) case. These skein relations deform GL(2) foam relations of Beliakova, Hogancamp, Putyra and Wehrli. We establish the Reidemeister move invariance of the resulting chain complexes assigned to link diagrams, giving us a link homology theory., Comment: 57 pages, 54 figures

In the first part of this paper, we constructed a filtered U(r)-equivariant stable homotopy type called the spectrum of strict broken symmetries sB(L) of links L given by closing a braid with r strands. We further showed that evaluating this spectrum on suitable U(r)-equivariant cohomology theories gives rise to a spectral sequence of link invariants, converging to the homology of the limiting spectrum. In this followup, we fix a positive integer n and apply a version of an equivariant K-theory known as Dominant K-theory, which is built from level n representations of the loop group of U(r). The E_2-term of the spectral sequence appears to be a deformation of sl(n)-link homology, and has the property that its value on the unlink is the Grothendieck group of level n-representations of the loop group of U(1). Seen in contrast to the standard interpretation of sl(n)-link homology using the fundamental representation of the quantum group U_q(sl(n)), suggests a level-rank duality at play., Comment: This paper is being withdrawn because it has been corrected and subsumed in Part II of the paper [arXiv:1910.07444]. A forthcoming replacement of Part III will be entirely about the Physics and Geometry that describes the natural appearance of Symmetry breaking and Link homologies in semiclassical gauge theories

We continue the development of the computability of the second real Johnson-Wilson theory. As ER(2) is not complex orientable, this gives some difficulty even with basic spaces. In this paper we compute the second real Johnson-Wilson theory for products of infinite complex projective spaces and for the classifying spaces for the unitary groups.

In this paper, we provide a new proof of the stable Adams conjecture. Our proof constructs a canonical null-homotopy of the stable J-homomorphism composed with a virtual Adams operation, by applying the $\mathrm{K}$-theory functor to a multi-natural transformation. We also point out that the original proof of the stable Adams conjecture is incorrect and present a correction. This correction is crucial to our main application. We settle the question on the height of higher associative structures on the mod $p^k$ Moore spectrum $\mathrm{M}_p(k)$ at odd primes. More precisely, for any odd prime $p$, we show that $\mathrm{M}_p(k)$ admits a Thomified $\mathbb{A}_n$-structure if and only if $n < p^k$. We also prove a weaker result for $p=2$., Comment: This update offers two different proofs of the stable Adams conjecture with applications to A_n structures on Moore spectra. The first proof uses permutative categories and is independent of Friedlander's argument. The second proof (from the earlier draft of this paper) uses a result by Friedlander on the classification of Gamma space fibrations

In this short note we study the topological Hoschschild homology of Eilenberg-MacLane spectra for finite cyclic groups. In particular, we show that the Eilenberg-MacLane spectrum H(Z/p^k) is a Thom spectrum for any prime p (except, possibly, when p=k=2) and we also compute its topological Hoschshild homology. This yields a short proof of the results obtained by Brun, and by Pirashvili except for the anomalous case p=k=2., Comment: Typos fixed

We prove that the Real Johnson-Wilson theories ER(n) are homotopy associative and commutative ring spectra up to phantom maps. We further show that ER(n) represents an associatively and commutatively multiplicative cohomology theory on the category of (possibly non-compact) spaces., Comment: 16 pages, version 2. Added a new section revisiting $ER(n)$-orientations of vector bundles and minor improvements to exposition. To appear in Proceedings of the Mid-Atlantic Topology Conference

The $ER(2)$-cohomology of $B\mathbb{Z}/(2^q)$ and $\mathbb{C}P^n$ are computed along with the Atiyah-Hirzebruch spectral sequence for $ER(2)^*(\mathbb{C}P^\infty)$. This, along with other papers in this series, gives us the $ER(2)$-cohomology of all Eilenberg-MacLane spaces. Since $ER(2)$ is $TMF_0(3)$ after a suitable completion, these computations also take care of that theory., Comment: 25 pages, version 2: minor changes to exposition, a few diagrams added. Comments welcome!

We take advantage of the internal algebraic structure of the Bockstein spectral sequence converging to ER(n)^*(pt) to prove that for spaces Z that are part of Landweber flat real pairs with respect to E(n), the cohomology ring ER(n)^*(Z) can be obtained from E(n)^*(Z) by base change. In particular, our results allow us to compute the Real Johnson-Wilson cohomology of the Eilenberg-MacLane spaces Z = K(Z, 2m+1), K(Z/2^q, 2m), K(Z/2, m) for all natural numbers $m$ and $q$, as well as connective covers of BO: BO, BSO, BSpin, and BO<8> (the last for n<3 only)., Comment: 21 pages; version 3 (final version): several minor corrections

We give an easy proof that the Morava K-theories for BO(q) and MO(q) are in even degrees. Although this is a known result, it had followed from a difficult proof that BP^*(BO(q)) was Landweber flat. Landweber flatness follows from the even Morava K-theory. We go further and compute an explicit description of K(n)_*(BO(q)) and K(n)_*(MO(q)) and reconcile it with the purely algebraic construct from Landweber flatness.

Using the Bockstein spectral sequence developed previously by the authors, we compute the ring ER(n)^*(BO(q)) explicitly. We then use this calculation to show that the ring spectrum MO[2^{n+1}] is ER(n)-orientable (but not ER(n+1)-orientable), where MO[2^{n+1}] is defined as the Thom spectrum for the self map of BO given by multiplication by 2^{n+1}.

Given a simple, simply connected compact Lie group G, let M be a G-space. We describe the quantization of the category of positive energy representations of the loop group of G at a given level and parametrized over the loop space LM. This procedure is described in terms of dominant K-theory of the loop group evaluated on the phase space given by the tangent bundle of basic gauge fields about a circle (parametrized over LM and with gauge symmetries given by the loop group LG). As such, our construction gives rise to a (categorical) BV-BRST type quantization for families of rational 2d CFTs with gauge symmetries parametrized over M. More concretely, we construct a holomorphic sheaf over a universal elliptic curve with values in dominant K-theory of the loop space LM, and show that each stalk of this sheaf is a cohomological functor of M. We also interpret this theory as a model of equivariant elliptic cohomology of M as constructed by Grojnowski and others., Comment: Exposition improved to interpret our construction as a (Categorical) BV-BRST quantization for parametrized 2d CFTs with gauge symmetries. Referee comments incorporated

Soergel bimodules and their Hochschild homology are known to be important in the context of link homology. In this article we observe that Soergel bimodules may be naturally identified as the cohomology of well-defined objects in the category of spectra. This allows us to define forms of Soergel bimodules over the integers after inverting 2, indexed by elements in Braid groups associated to compact Lie groups of adjoint type. Reducing the Soergel bimodules modulo an odd prime, we endow the bimodules with an action of the reduced Steenrod algebra. This action extends to an action of the reduced Steenrod algebra on the Hochschild homology of Soergel bimodules over the primary field F_p for odd primes p. In the special case of the n-stranded Braid group, our results allow us to define the triply graded link homology over any ring where 2 is invertible, and deduce that the reduced Steenrod algebra acts on triply graded link homology over the field F_p for odd primes p., Comment: The earlier version of this paper has been split to carve out the part that deals with the action of the reduced Steenrod Algebra on Soergel bimodules and triply graded link homology. This action is described directly, with no reference to the Landweber Novikov Algebra. A future document will address the action of the Landweber-Novikov algebra on Soergel bimodules and also correct previous errors

Localized at almost all primes, we describe the structure of differentials in several important spectral sequences that compute the cohomology of classifying spaces of topological Kac-Moody groups. In particular, we show that for all but a finite set of primes, these spectral sequences collapse and that there are no additive extension problems. We also describe some appealing consequences of these results. The main tool is the use of the naturality properties of unstable Adams operations on these classifying spaces., Comment: The construction of the local unstable Adams operation, needed for the proof of the main theorem, that was implicit in Section 3 has now been presented explicitly as a new section

We consider an oriented version of the stable symplectic category defined in \cite{N}. We show that the group of monoidal automorphisms of this category, that fix each object, contains a natural subgroup isomorphic to the solvable quotient (or a graded-abelian quotient) of the Grothendieck--Teichm\"uller group. This establishes a stable version of a conjecture of Kontsevich which states that groups closely related to the Grothendieck--Teichm\"uller group act on the moduli space of certain field theories \cite{KO}. The above quotient of the Grothendieck--Teichm\"uller group is also shown to be the motivic group of monoidal automorphisms of a canonical representation (or fiber functor) on the stable symplectic category., Comment: The paper has been largely reorganized to interpret the action of the Grothendieck--Teichm\"uller group in the context of a conjecture of Kontsevich. The title has been changed accordingly. The section on the Waldhausen K-theory of $s\Omega$ has been removed and will form part of a separate document. All other sections have been preserved

We study a stabilization of the symplectic category introduced by A. Weinstein as a domain for the geometric quantization functor. The symplectic category is a topological category with objects given by symplectic manifolds, and morphisms being suitable lagrangian correspondences. The main drawback of Weinstein's symplectic category is that composition of morphisms cannot always be defined. Our stabilization procedure rectifies this problem while remaining faithful to the original notion of composition. The stable symplectic category is enriched over the category of spectra (in particular, its morphisms can be described as infinite loop spaces representing the space of immersed lagrangians), and it possesses several appealing properties that are relevant to deformation, and geometric quantization., Comment: More details have been added, typos have been corrected, and the theory has been expanded. In particular, the stable symplectic category has been shown to have an A-infinity structure. Two sections have been removed and will form separate postings in the future

Baker and Richter construct a remarkable $A_\infty$ ring-spectrum $M\Xi$ whose elements possess characteristic numbers associated to quasisymmetric functions; its relations, on one hand to the theory of noncommutative formal groups, and on the other to the theory of omnioriented (quasi)toric manifolds [in the sense of Buchstaber, Panov, and Ray], seem worth investigating., Comment: A revision of a talk at the Queen's University (Belfast) conference [August 2011] on toric manifolds, http://toricmethodsbelfast.zzl.org/

The Madsen-Tillmann spectra defined by categories of three- and four-dimensional Spin manifolds have a very rich algebraic structure, whose surface is scratched here., Comment: This replaces arXiv:math/0610047: Chiral structures on the 4D spin cobordism category

We consider real spectra, collections of Z/(2)-spaces indexed over Z oplus Z alpha with compatibility conditions. We produce fibrations connecting the homotopy fixed points and the spaces in these spectra. We also evaluate the map which is the analogue of the forgetful functor from complex to reals composed with complexification. Our first fibration is used to connect the real 2^{n+2}(2^n-1)-periodic Johnson--Wilson spectrum ER(n) to the usual 2(2^n-1)-periodic Johnson--Wilson spectrum, E(n). Our main result is the fibration Sigma^{lambda(n)} ER(n) --> ER(n) --> E(n)$, where lambda(n) = 2^{2n+1}-2^{n+2}+1., Comment: This is the version published by Geometry & Topology Monographs on 27 January 2007

We study the topology of spaces related to Kac-Moody groups. Given a split Kac-Moody group over the complex numbers, let K denote the unitary form with maximal torus T having normalizer N(T). In this article we study the cohomology of the flag manifold K/T, as a module over the Nil-Hecke ring, as well as the (co)homology of K as a Hopf algebra. In particular, if F is a field of positive characteristic, we show that H_*(K,F) is a finitely generated algebra, and that H^*(K,F) is finitely generated only if K is a compact Lie group . We also study the stable homotopy type of the classifying space BK and show that it is a retract of the classifying space BN(T). We illustrate our results with the example of rank two Kac-Moody groups., Comment: The presentation and proofs have been streamlined. There is no change in the statements of the results, or the idea of the proof

Given a semisimple, compact, connected Lie group G with complexification G^c, we show there is a stable range in the homotopy type of the universal moduli space of flat connections on a principal G-bundle on a closed Riemann surface, and equivalently, the universal moduli space of semistable holomorphic G^c-bundles. The stable range depends on the genus of the surface. We then identify the homology of this moduli space in the stable range in terms of the homology of an explicit infinite loop space. Rationally this says that the stable cohomology of this moduli space is generated by the Mumford-Morita-Miller kappa-classes, and the ring of characteristic classes of principal G-bundles, H^*(BG). We then identify the homotopy type of the category of one-manifolds and surface cobordisms, each equipped with a flat G-bundle. We also explain how these results may be generalized to arbitrary compact connected Lie groups. Our methods combine the classical techniques of Atiyah and Bott, with the new techniques coming out of Madsen and Weiss's proof of Mumford's conjecture on the stable cohomology of the moduli space of Riemann surfaces., Comment: 22 pages

We give a topological interpretation of the highest weight representations of Kac-Moody groups. Given the unitary form G of a Kac-Moody group (over C), we define a version of equivariant K-theory, K_G on the category of proper G-CW complexes. We then study Kac-Moody groups of compact type in detail (see Section 2 for definitions). In particular, we show that the Grothendieck group of integrable hightest weight representations of a Kac-Moody group G of compact type, maps isomorphically onto K_G^*(EG), where $EG$ is the classifying space of proper G-actions. For the affine case, this agrees very well with recent results of Freed-Hopkins-Teleman. We also explicitly compute K_G^*(EG) for Kac-Moody groups of extended compact type, which includes the Kac-Moody group E_{10}., Comment: Update to the published version with some mistakes in Section 4 corrected. No change to the statements of the theorems

In this paper we study the topology of the space $\I_\omega$ of complex structures compatible with a fixed symplectic form $\omega$, using the framework of Donaldson. By comparing our analysis of the space $\I_\omega$ with results of McDuff on the space $\cat J_\omega$ of compatible almost complex structures on rational ruled surfaces, we find that $\I_\omega$ is contractible in this case. We then apply this result to study the topology of the symplectomorphism group of a rational ruled surface, extending results of Abreu and McDuff., Comment: Sign mistake in the formula for the cohomology in twisted case fixed. Reorganized sections 4 and 5 and added more detail to proofs. To appear in Duke Math. Journal

In this paper we apply Donaldson's general moment map framework for the action of a symplectomorphism group on the corresponding space of compatible (almost) complex structures to the case of rational ruled surfaces. This gives a new approach to understanding the topology of their symplectomorphism groups, based on a result of independent interest: the space of compatible integrable complex structures on any symplectic rational ruled surface is (weakly) contractible. We also explain how in general, under this condition, there is a direct relationship between the topology of a symplectomorphism group, the deformation theory of compatible complex structures and the groups of complex automorphisms of these complex structures., Comment: To appear in the issue of the Journal of Symplectic Geometry devoted to the Stare Jablonki conference proceedings

We construct an S^1-equivariant prospectrum that models the Atiyah dual of a free loop space of a manifold. By applying a suitably completed S^1-equivariant K-theory to the Atiyah dual, we show how to recover the Witten genus of the manifold. The main technical tool is a Tits building for the loop group. We use this building to construct a dualizing spectrum for the loop group and relate it to work of Freed, Hopkins and Teleman.

We compute the Eells-Kuiper invariant of the Berger manifold SO(5)/SO(3) and determine that it is diffeomorphic to the total space of an S^3-bundle over S^4. This answers a question raised by K. Grove and W. Ziller., Comment: LaTeX, 17 pages. v2: proofs of corollaries added

There has been renewed interest in $\mathbb{S}^3$-bundles over $\mathbb{S}^4$ since K. Grove and W. Ziller constructed metrics on nonnegative curvature on the total spaces of these bundles. In this paper we write down necessary and sufficient conditions for a CW complex to be homotopy equivalent to such a bundle. We also show that for a manifold homotopy equivalent to such a bundle, in certain cases, there is no obstruction to homeomorphism. We use this to show that the Berger manifold, $\text{Sp}(2)/\text{Sp}(1)$, is PL-homeomorphic to such a bundle. This question was raised in the paper by Grove and Ziller since this manifold, which admits a normal homogeneous metric of positive sectional curvature, has the cohomology ring of such a bundle. The principal technique used is the study of the Serre spectral sequence of various fibrations., Comment: 12 pages, no figures