For the observation or evidence of negative mass(energy)
In 1998, an observation by both the HSS team and SCP team obtained a negative mass density from inspected field equations over 70years.(field eq. has a Lamda=0)
SCP(Supernova Cosmology Project) team : If Lamda=0, Omega_M= - 0.4(±0.1)
http://arxiv.org/abs/astro-ph/9805201 refer to 7P
HSS(The High-z Supernova Search) team : If Lamda=0, Omega_M = - 0.38(±0.22)
http://arxiv.org/abs/astro-ph/9805201 refer to 14P
However, the two teams which judged that negative mass and negative energy level could not exist in our universe based on "the problem of the transition of the energy level of minus infinity" and they instead revised the field equation by inserting the cosmological constant.
We must to know that not the equation has disposed the value, but our thought disposed the value.
Moreover, we considered vacuum energy as the source of cosmological constant Lamda, but the current result of calculation shows 10120, which is unprecedented even in the history of Physics.
However, if "the problem of the transition of the energy level of minus infinity" does not occur, and thus negative and positive mass can coexist, what would happen?
It is well known that a cosmological constant can respond to the negative mass density.
peff = -Lamda/4piG
Lamda is positive, so peff is negative.
Please view to my article and simulation video