  Type Ia Supernovae (SNe Ia) are widely used as standard candles to probe the
Universe. However, how these fierce explosions are produced itself is still a
highly debated issue. There are mainly two popular models for SNe Ia, i.e. the
double-degenerate scenario and the single-degenerate scenario. The
double-degenerate scenario suggests that SNe Ia are produced by the coalescence
of two degenerate white dwarfs, while the single-degenerate scenario suggests
that the continuous accretion of a single degenerate white dwarf from its
normal stellar companion will finally lead to a disastrous explosion when it is
over-massive, resulting in an SN Ia. The rapid development of the gravitational
wave astronomy sheds new light on the nature of SNe Ia. In this study, we
calculate the gravitational wave emissions of double white dwarf coalescences
and compare them with the sensitivities of several upcoming detectors. It is
found that the gravitational wave emissions from double white dwarf mergers in
the locale universe are strong enough to be detected by LISA. We argue that
LISA-like gravitational wave detectors sensitive in the frequency range of 0.01
- 0.1 Hz will be a powerful tool to test the double-degenerate model of SNe Ia,
and also to probe the Universe.
