A tendex line (from the Latin "tendere": To stretch) is a traversal line describing the path matter takes through the

accretion disc An accretion disk is a structure (often a circumstellar disk) formed by diffuse material in orbital motion around a massive central body. The central body is most frequently a star. Friction, uneven irradiance, magnetohydrodynamic effects, and ...

of a

black hole A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. Th ...

. A tendex line typically follows a spiral around the black hole descending to the

event horizon In astrophysics, an event horizon is a boundary beyond which events cannot affect an outside observer. Wolfgang Rindler coined the term in the 1950s. In 1784, John Michell proposed that gravity can be strong enough in the vicinity of massive c ...

. Matter on this line experiences a stretching effect, while vortex lines describe a twisting effect. Both of these types of lines can be used to visualise black holes, and the ways in which

spacetime In physics, spacetime, also called the space-time continuum, is a mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams are useful in visualiz ...

warps around them. They may also help to explain phenomena such as the 'kicks' observed in simulations of merging black holes as they are flung away from their host galaxies, and may also help in the search for

gravitational waves Gravitational waves are oscillations of the gravitational field that travel through space at the speed of light; they are generated by the relative motion of gravitating masses. They were proposed by Oliver Heaviside in 1893 and then later by H ...

References

Black holes {{black-hole-stub

See also

References