Oppsum

Oppsum is a fictional metallic material frequently appearing in speculative science and science fiction contexts. It is described as a dense, corrosion-resistant solid with exceptional energy density and broad radiation tolerance, making it a candidate for advanced engineering applications.

Despite variations, common depictions describe Oppsum as having a high melting point, near-metallic electrical conductivity, and a crystalline lattice that remains intact under extreme thermal and magnetic fields.

Synthesis in most depictions involves a multi-step, high-pressure, high-temperature process that combines hypothetical precursors and traps a metastable phase through rapid quenching. Some stories locate the production in orbiting fabrication facilities or specialized reactors on the Moon or asteroids.

Applications include compact energy storage, such as high-density batteries, propulsion components for advanced spacecraft, and radiation shielding. In some narratives, Oppsum serves as a testbed for new theories of superconductivity and quantum materials due to its claimed properties.

In fictional contexts, Oppsum's production is expensive and resource-intensive, with safety and environmental concerns explored as part of its speculative impact on supply chains, geopolitics, and technology access.