Maskhål

Maskhål is the Swedish term for a wormhole, a hypothetical tunnel through spacetime that connects distant regions of the universe or even different universes. The concept arises from solutions to Einstein’s general relativity, notably the Einstein–Rosen bridge described in 1935, which links two separate regions of spacetime. In its original form, such bridges are typically non-traversable because they collapse too quickly for anything to pass through.

A traversable maskhål requires regions of negative energy density or exotic matter to hold the throat open. This idea was popularized by Morris and Thorne in the late 1980s. The required matter violates known energy conditions and has not been observed on macroscopic scales. Realistic models face severe stability issues, tidal forces, and compatibility with quantum gravity.

If they exist, wormholes could in principle enable shortcuts for space travel or, in some models, enable time travel, raising causality concerns. However, no empirical evidence supports their existence, and all proposed solutions remain speculative.

In physics and cosmology, maskhål are useful theoretical laboratories for exploring spacetime topology, energy conditions, and quantum effects in gravity. They are distinct from black holes, which involve horizons that trap matter and light. Searches for observational signatures, such as unusual gravitational lensing, have yet to yield detections.