permittmus

Permittimus is a fictional material property used in speculative physics and science fiction to describe a hypothetical ability of a material to selectively permit certain electromagnetic interactions while suppressing others. It is not an established quantity in real-world physics, and its definition varies by author or thought experiment.

Origin and context: The term arises in speculative literature and pedagogical exercises to explore how engineered media might route energy or conceal objects without violating fundamental laws. In these contexts, permittimus is often treated as a tunable parameter or as a functional combination of dielectric and magnetic response designed to produce directional, frequency-dependent, or mode-selective transmission.

Characterization and applications: In fiction and thought experiments, permittimus can be presented as a dimensionless control that adjusts a material's response to electromagnetic waves, enabling devices such as cloaks, waveguides, or energy routers. Some renditions feature anisotropic or nonreciprocal permittimus, yielding different transmission for forward versus backward propagation or for different polarizations.

Limitations and reception: There is no empirical evidence for permittimus as a real material property. It remains a conceptual or narrative tool used to discuss metamaterials, cloaking, and energy-routing ideas. Proponents view it as a useful heuristic, while critics emphasize the risk of conflating fictional constructs with real physics.

See also: metamaterials, permittivity, permeability, electromagnetic cloaking, thought experiments.