[1][2][3] With Joseph Polchinski, Bousso proposed the string theory landscape as a solution to the cosmological constant problem.
Bousso did postdoctoral research at Stanford University until 2000, and at the Kavli Institute for Theoretical Physics in Santa Barbara until 2002.
In 2012, Bousso was elected Fellow of the American Physical Society "for fundamental discoveries in the field of quantum cosmology, including the covariant entropy bound and the string landscape.
[15][16] In 2000, Bousso and Joseph Polchinski argued that string theory has many long-lived vacua, including solutions compatible with the observed positive value of the cosmological constant (vacuum energy).
"[17][5] Bousso has developed an approach to the cosmological measure problem,[18] with the ultimate goal of testing the string theory landscape.