Hilbert spaces can be used to study the harmonics of vibrating strings.A Feynman diagram of another way the Higgs boson may be produced at the LHC. Here, two quarks each emit a W or Z boson, which combine to make a neutral Higgs. [[1]]
This image of the vortex trailing from the right wingtip of an agricultural aeroplane clearly shows the region of downwash to the left of the vortex core