Cosmological Constant as the Coefficient of Quantum Tunneling in the Universe Exterior

In this work we suggest a simple model of the cosmological constant as the coefficient of the quantum tunneling of vacuum fluctuations (with wave length larger than Planck length) at tiny, boundary spherical shell of the universe (with thickness equivalent to Planck length and radius equivalent to scale factor). Roughly speaking, given fluctuations can, by quantum tunneling (i.e. scattering with a potential barrier with highness equivalent to Planck energy and width proportional to, approximately, three hundred Planck length) leave universe and arrive in its exterior, i.e. multi-universe (in sense of Linde chaotic inflation theory universe can be considered as a causally-luminally connected space domain while its exterior can be considered as a space domain without causal-luminal connections with universe). It is in full agreement with usual quantum mechanics and quantum field theory as well as WMAP observational data (especially fine tuning condition).