dS≥0
From the second law of thermodynamics, this simple equation best represents me. Any place I organise ends up getting messy after some time.
Gμν+gμνΛ=8πGc4Tμν
This many-in-one is a set of greatest equations known as Einstien's Field Equations that decribes the space-time.
∂2ξ∂t2=v2∇2ξ
Somehow, this equation appears almost everywhere I seem to think - sound, light, water, gravity, slinky, etc. This is the wave equation.
L=−14FμνFμν+iˉψγμDμψ+h.c.+ˉψiyijψjϕ+h.c.+|Dμϕ|2−V(ϕ)
The simplified Standard Model Lagrangian describes most of the interactions as processes in our Universe.