  The goal of this whitepaper is to give a comprehensive overview of the rich
field of forward physics. We discuss the occurrences of BFKL resummation
effects in special final states, such as Mueller-Navelet jets, jet gap jets,
and heavy quarkonium production. It further addresses TMD factorization at low
x and the manifestation of a semi-hard saturation scale in (generalized) TMD
PDFs. More theoretical aspects of low x physics, probes of the quark gluon
plasma, as well as the possibility to use photon-hadron collisions at the LHC
to constrain hadronic structure at low x, and the resulting complementarity
between LHC and the EIC are also presented. We also briefly discuss diffraction
at colliders as well as the possibility to explore further the electroweak
theory in central exclusive events using the LHC as a photon-photon collider.
