Semantic Factorization and Descent

Let $\mathbb{A}$ be a $2$-category with suitable opcomma objects and pushouts. We give a direct proof that, provided that the codensity monad of a morphism $p$ exists and is preserved by a suitable morphism, the factorization given by the lax descent object of the higher cokernel of $p$ is up to isomorphism the same as the semantic factorization of $p$, either one existing if the other does. The result can be seen as a counterpart account to the celebrated B\'{e}nabou-Roubaud theorem. This leads in particular to a monadicity theorem, since it characterizes monadicity via descent. It should be noted that all the conditions on the codensity monad of $p$ trivially hold whenever $p$ has a left adjoint and, hence, in this case, we find monadicity to be a $2$-dimensional exact condition on $p$, namely, to be an effective faithful morphism of the $2$-category $\mathbb{A}$.Comment: Full revision, new diagrams, 48 page

Planar Refrains

My practice explores phenomenal poetic truths that exist in fissures between the sensual and physical qualities of material constructs. Magnifying this confounding interspace, my work activates specific instruments within mutable, relational systems of installation, movement, and documentation. The tools I fabricate function within variable orientations and are implemented as both physical barriers and thresholds into alternate, virtual domains. Intersecting fragments of sound and moving image build a nexus of superimposed spatialities, while material constructions are enveloped in ephemeral intensities. Within this compounded environment, both mind and body are charged as active sites through which durational, contemplative experiences can pass. Reverberation, the ghostly refrain of a sound calling back to our ears from a distant plane, can intensify our emotional experience of place. My project Planar Refrains utilizes four electro-mechanical reverb plates, analog audio filters designed to simulate expansive acoustic arenas. Historically these devices have provided emotive voicings to popular studio recordings, dislocating the performer from the commercial studio and into a simulated reverberant territory of mythic proportions. The material resonance of steel is used to filter a recorded signal, shaping the sound of a human performance into something more transformative, a sound embodying otherworldly dynamics. In subverting the designed utility of reverb plates, I am exploring their value as active surfaces extending across different spatial realities. The background of ephemeral sonic residue is collapsed into the foreground, a filter becomes sculpture, and this sculpture becomes an instrument in an evolving soundscape

The spin structure of the proton at low xx and low Q2Q^2 in two-dimensional bins from COMPASS

The longitudinal double spin asymmetries $A_1^p$ and the spin dependent structure function of the proton $g_1^p$ were extracted from COMPASS data in the region of low Bjorken scaling variable $x$ and low photon virtuality $Q^2$. The data were taken in 2007 and 2011 from scattering of polarised muons off polarised protons, resulting in a sample that is 150 times larger than the one from the previous experiment SMC that pioneered studies in this kinematic region. For the first time, $A_1^p$ and $g_1^p$ were evaluated in this region in two-dimensional bins of kinematic variables: $(x,Q^2)$, $(\nu ,Q^2)$, $(x,\nu)$ and $(Q^2,x)$. The following kinematic region was investigated: $4\times 10^{-5}<x<4\times 10^{-2}$, $0.001$~(GeV/$c$)$^2<Q^2<1$~(GeV/$c$)$^2$ and $14$~GeV$<\nu <194$~GeV. The obtained results were confronted with theoretical models.Comment: 5 pages, 3 figures, DIS 2016 Conference Proceedings, to appear in the proceedings of the XXIV International Workshop on Deep-Inelastic Scattering and Related Subjects, DESY Hamburg, Germany, April 11-15, 201