Jet Substructure @ the LHC - from Boosted to Bread & Butter Particle Physics

Jets are outputs of clustering algorithms that group the energy cells
of the calorimeter components of a detector in a well-defined way.
After a brief introduction, I will review selected new ideas in jet
physics. In the first part, I will discuss how the use of a
non-deterministic jet-algorithm can render stability to jet
observables. In the second part, I will introduce a new proposal
where jets become a superset of both traditional objects such as
QCD-jets, photons, and electrons, and more unconventional objects
such as photon-jets and electron-jets, defined as collinear photons
and electrons, respectively.  Since standard objects such as single
photons become a subset of jets in this approach, standard jet
substructure techniques are incorporated into the photon finder
toolbox. I demonstrate that, for a single photon identification
efficiency of 80% or above, the use of jet substructure techniques
reduces the number of QCD-jets faking photons by factors of 2.5 to 4.