Upgrade Physics Prospects with the ATLAS Experiment

The High Luminosity run of the Large Hadron Collider (LHC) will start in 2026 and aims to collect $3000\;\mathrm{fb}^{-1}$ of proton-proton collisions by 2037. This enormous dataset will increase the discovery potential of the LHC and allow precision measurements of Standard Model processes. However, the very high instantaneous luminosity of $5-7 \times 10^{34}\;\mathrm{cm^{-}2 s^{-1}}$ poses serious challenges in terms of high “pile-up” of 140 or 200 overlapping proton-proton collisions per bunch crossing inside the ATLAS detector. In this talk, I will summarise the planned ATLAS detector upgrades and the analysis techniques, including pile-up mitigation, for High Luminosity-LHC running. I will also present the physics prospects for the ATLAS experiment, including results for precision measurements of the $125\;\mathrm{GeV}$ Higgs boson and the top quark, for vector boson scattering and the physics reach for supersymmetric and other beyond-the-Standard-Models.