English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

QCD interactions for equal-mass fermion flavours are flavour blind. This factis often used to state that sea-quark loop contributions are equal for $u$ and$d$ quarks in the mass symmetric case and therefore these disconnectedsea-quark loop contributions cannot contribute to the well-known $\bar d - \baru$ asymmetry in the proton. Instead, it is argued that one must look to theconnected sector of lattice QCD correlation functions to find this difference.In this presentation, we note that these statements are true only when oneincludes unphysical contributions in the sea-quark-loop sector, contributionsfrom baryons that do not appear in the physical spectrum. Because theseunphysical contributions must be eliminated from the sea-quark loop sector viathe connected sector, the assertion that the $\bar d$ and $\bar u$ sea-quarkloop contributions cancel in $\bar{d} - \bar{u}$ is incorrect. Upon consideringonly physically observed baryons in the loop contributions, we illustrate animportant contribution from the sea-quark loop sector to $\bar d - \bar u$.

Sea-quark loop contributions to the $\bar d$-$\bar u$ asymmetry in the proton