Vacuum Selection on the String Landscape
نویسنده
چکیده
I examine some non-anthropic approaches to the string landscape. These approaches are based on finding the initial conditions of the universe using the wavefunction of the multiverse to select the most probable vacuum out of this landscape. All approaches tackled so far seems to have their own problems and there is no clear cut alternative to anthropic reasoning. I suggest that finding the initial conditions may be irrelevant since all possible vacua on the landscape are possible initial state conditions and eternal inflation could generate all the other vacua. We are now left to reason out why we are observing the small value of the cosmological constant (CC). I address this issue in the contest of noncritical string theory in which all values of the cosmological constant on the landscape are departures from critical equilibrium state.
منابع مشابه
Where in the String Landscape is Quintessence
We argue that quintessence may reside in certain corners of the string landscape. It arises as a linear combination of internal space components of higher rank forms, which are axion-like at low energies, and may mix with 4-forms after compactification of the Chern-Simons terms to 4D due to internal space fluxes. The mixing induces an effective mass term, with an action which preserves the axio...
متن کاملLandscape Predictions from Cosmological Vacuum Selection
In BP models with hundreds of fluxes, we compute the effects of cosmological dynamics on the probability distribution of landscape vacua. Starting from generic initial conditions, we find that most fluxes are dynamically driven into a different and much narrower range of values than expected from landscape statistics alone. Hence, cosmological evolution will access only a tiny fraction of the v...
متن کاملA New Perspective to Cosmic Evolution and Vacuum Selection on a Superspace based on Symmetry Principles
In this short note, I conjecture that a flat compact universe emerged out of nothing with all its symmetries intact: Poincare invariance, conformal invariance and supersymmetry, and a zero energy density. Its subsequent evolution and spontaneous breaking of these symmetries or by quantum fluctuations leads to topological defects on this superspace which are the fields we observe (or haven’t yet...
متن کاملEmpirical Constraints on Vacuum Decay in the Stringy Landscape
It is generally considered as self evident that the lifetime of our vacuum in the landscape of string theory cannot be much shorter than the current age of the universe. Here I show why this lower limit is invalid. A certain type of " parallel universes " is a necessary consequence of the string-landscape dynamics and might well allow us to " survive " vacuum decay. As a consequence our stringy...
متن کاملSimplified Chain Inflation
We propose a simplified chain inflation model and calculate the primordial power spectra of the scalar and tensor fluctuations. The spectral index and the tensor-scalar ratio are respectively 0.972 and 0.089 which are consistent with present cosmological observations. Inflation models proposed by Guth in [1] not only explain the large-scale homogeneity and isotropy of the universe, but also pro...
متن کامل