claim: Vatican City was established in 1930.
evidence: Artificial dielectrics are fabricated electromagnetic materials consisting of synthetic substances , usually constructed in an orderly arrangement , such as array .. electromagnetic. electromagnetic field. dielectrics. dielectrics. The arranged materials , and the distances between them are usually evenly spaced on , or within , a substrate .. substrate. substrate ( materials science ). Hence , the arrays of inclusions are in a periodic or lattice structure .. lattice. lattice model ( physics ). Also , the lattice spacing is smaller than the impinging electromagnetic wavelength .. electromagnetic. electromagnetic field. lattice. lattice model ( physics ). wavelength. wavelength. These were first conceptualized , constructed and deployed for interaction in the microwave frequency range in the 1940s and 1950s .. microwave. microwave. The constructed medium , the artificial dielectric , has an effective permittivity and effective permeability , as intended .. permittivity. permittivity. permeability. permeability ( electromagnetism ). In addition , some artificial dielectrics may consist of irregular lattices , random mixtures , or a non-uniform concentration of particles .. dielectrics. dielectrics. Artificial dielectrics came into use with the radar microwave technologies developed between the 1940s and 1970s .. microwave. microwave. dielectrics. dielectrics. The term `` artificial dielectrics '' came into use because these are macroscopic analogues of naturally occurring dielectrics .. macroscopic. macroscopic. dielectrics. dielectrics. The difference between the natural and artificial substance is that the atoms or molecules are artificially -LRB- human -RRB- constructed materials .. Artificial dielectrics were proposed because of the need for lightweight structures and components for various microwave delivery devices .. microwave. microwave. dielectrics. dielectrics. Artificial dielectrics are a direct historical link to metamaterials .. dielectrics. dielectrics. metamaterials. metamaterials