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We investigate a Friedmann universe filled with a tachyon scalar field, whichbehaves as dustlike matter in the past, while it is able to accelerate theexpansion rate of the universe at late times. The comparison with type Iasupernovae (SNIa) data allows for evolutions driving the universe into a BigBrake. Some of the evolutions leading to a Big Brake exhibit a large variationof the equation of state parameter at low redshifts which is potentiallyobservable with future data though hardly detectable with present SNIa data.The soft Big Brake singularity occurs at finite values of the scale factor,vanishing energy density and Hubble parameter, but diverging deceleration andinfinite pressure. We show that the geodesics can be continued through the BigBrake and that our model universe will recollapse eventually in a Big Crunch.Although the time to the Big Brake strongly depends on the present values ofthe tachyonic field and of its time derivative, the time from the Big Brake tothe Big Crunch represents a kind of invariant timescale for all fieldparameters allowed by SNIa.

Will the tachyonic Universe survive the Big Brake?