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The Standard Model (SM) of particle physics, grounded in the SU_C(3) × SU_L(2) × U_Y(1) gauge group, remains the most experimentally validated theory at fundamental scales. However, the SM does not address several critical issues, including Higgs boson stability, neutrino masses, baryon asymmetry, and dark matter. To address these limitations, various theories introduce new symmetries, dimensions, and particles, though experimental support remains elusive. This thesis adopts a model-independent approach to parameterize new physics effects through the Standard Model Effective Field Theory (SMEFT). We investigate charged and neutral triple gauge couplings at an electron-positron collider with polarized initial beams at √s = 250 GeV, utilizing polarization and spin-correlations of weak bosons. The CP-odd nature of spin observables necessitates final state jet tagging, for which neural network and boosted decision tree models were developed. The analysis of four-jet events quantifies the impact of interference on the limits of anomalous couplings, with jet charge used to identify the two W bosons. Additionally, we explore the anomalous chromo and electric dipole moments of the top quark at the LHC through single top quark production associated with a W+W- boson in the leptonic final state. The reconstruction of two missing neutrinos employs the MT2-assisted on-shell algorithm. The final section investigates quantum entanglement (QE) in high-energy scattering processes. QE measurements are quantified for 2⊗2, 2⊗3, and 3⊗3 bipartite states and 2⊗2⊗3 tripartite states, exemplified by the tt̄Z process at the LHC in the presence of dimension-8 operators. The QE of ZZ states from Higgs boson decay is analyzed to assess CP-sensitive anomalous HZZ couplings. |