  Astronomical observations have shown that the expansion of the universe is at
present accelerating, in a way consistent with the presence of a positive
cosmological constant. This is a major puzzle, because we do not understand:
why the cosmological constant is so small; why, being so small, it is not
exactly zero; and why it has precisely the value it must have to make the
expansion start accelerating just at the epoch when we are observing the
universe. We present a new model of cosmology, which we call the stryngbohtyk
model, that solves all these problems and predicts exactly the value that the
cosmological constant must have. The predicted value agrees with the observed
one within the measurement error. We show that in the stryngbohtyk model, the
fact the cosmological constant starts being important at the present epoch is
not a coincidence at all, but a necessity implied by our origin in a planet
orbiting a star that formed when the age of the universe was of the same order
as the lifetime of the star.
