D. String theory landscape and a graceful exit a phase reminiscence to the Hagedorn phase [933]. Note, a very similar picture would unfold in any neighboring throats, (MS)SM throat is not a unique one. The vacuum energy in a string theory landscape can be written as: where c$_{i}$ < ∼ 1 are constants and n$_{i}$ are flux quantum numbers (note that Λ has dimension mass 2 in our notation as it enters the Einstein equation as Λ g$_{µν}$ ). All in all, string theory (from the landscape point of view) could have from 10 500 to even 10 1000 vacua [45, 56–58], with the vast majority of those having large cosmological constants. In addition, our knowledge of the distribution of gauge groups over the landscape suggests that one out of 10 10 vacua have the SM spectrum, at least in simple models [59–61]. Even if this fraction is much smaller on the whole landscape, there are so many vacua that it seems likely very many will have a SM-like spectrum. From statistical arguments, most vacua should have badly broken SUSY, with large F -terms in the SUSY breaking sector. In addition, there exist vacua with large cosmological constant that are “almost SUSY” in the sense of [57, 934]. These vacua have vanishing (or nearly vanishing) F -terms, and their cosmological constant and SUSY breaking are provided by a D -term, such as that created by an anti-brane. Upon decay of the D -term, the remaining vacuum has small Λ and low energy SUSY. The original model of [55] is almost SUSY in this sense because anti-D3-branes provide both the cosmological constant and SUSY breaking. There are also examples of toy “friendly landscape” models [935], in which the dynamics of N scalars create a landscape of vacua. The landscape can also harbor negative Λ [936]. Also, [877] has discussed the importance of negative Λ vacua in possibly separating parts of the landscape from each other. It is expected that small jumps in Λ with small bubble tension τ to be the most com- mon decays, which can in fact be quite rapid [284]. In Ref. [937] the authors have argued that resonance can also play an important role in tunneling across a landscape of many metastable vacua. Also, the fact that there are many possible decays, as emphasized by [938], the whole landscape, including the MSSM-like vacua, will be populated eventually 235 V = M 2 $_{P}$Λ = M 2 $_{P}$Λ$_{0}$ + $_{α}$− 2 ∑ i c$_{i}$n 2 i , (490)