Non-linear optics has dealt physics another wild card:
Here's part of A.V.Gorbach & D.V. Skryabin's abstract, from Nature Photonics 1, 653 - 657 (1 Nov. 2007)
Light trapping in gravity-like potentials and expansion of supercontinuum spectra in photonic-crystal fibres
Femtosecond pulses of light propagating along photonic-crystal fibres can generate a broad optical supercontinuum ... Among the physical principles underlying supercontinuum generation are soliton emission7, a variety of four-wave mixing processes , Raman-induced soliton self-frequency shift
, and dispersive wave generation mediated by solitons...all of the above effects contribute to supercontinuum generation, none of them can explain the generation of blue and violet light from infrared femtosecond pump pulses.
we argue that the most profound role in the shaping of the short-wavelength edge of the continuum is played by the effect of radiation trapping in a gravity-like potential created by accelerating solitons. The underlying physics...has a straightforward analogy with the inertial forces acting on an observer moving with a constant acceleration.