Model Breaking Measure for Cosmological Surveys
  Recent observations have led to the establishment of the concordance LCDM
model for cosmology. A number of experiments are being planned to shed light on
dark energy, dark matter, inflation and gravity, which are the key components
of the model. To optimize and compare the reach of these surveys, several
figures of merit have been proposed. They are based on either the forecasted
precision on the LCDM model and its expansion, or on the expected ability to
distinguish two models. We propose here another figure of merit that quantifies
the capacity of future surveys to rule out the LCDM model. It is based on a
measure of the difference in volume of observable space that the future surveys
will constrain with and without imposing the model. This model breaking figure
of merit is easy to compute and can lead to different survey optimizations than
other metrics. We illustrate its impact using a simple combination of
supernovae and BAO mock observations and compare the respective merit of these
probes to challenge LCDM. We discuss how this approach would impact the design
of future cosmological experiments.
