String landscape
The string landscape describes the total amount of all possible solutions to string theory . This means, for example, the different Calabi-Yau manifolds , the different descriptions of the behavior of the D-branes, the different ISB models ("intersecting brane" models) or the different string vacuums. However, the presumed number of different solutions is roughly 10 to the power of 500.
overview
Because the string equations are extremely complex, they have several different solutions, all of which describe a universe with certain free parameters, false vacuums, and compactized dimensions. Somewhere in this “landscape” are the values for our universe. Here, the anthropic principle also plays a role, which immediately excludes the "areas" of the landscape whose parameters do not allow intelligent life in the universe. The Bayesian concept of probability can also be used to calculate how probable certain configurations in this regard are in the universe.
Connection with the ISB model
In 2003 a model was developed that describes D-branes that intersect, i.e. interact with one another. It interprets the topological properties of these branes as decisive for the laws that apply in the universe, since every other "brane configuration" describes a different model of our universe. Here, too, there is a string landscape, i.e. a collection of all possible topological configurations, whereby those for our universe still have to be found.
Individual evidence
- ↑ "The number of metastable vacua is not known exactly, but commonly quoted estimates are of the order 10 500 " M. Douglas : The statistics of string / M theory vacua . In: JHEP , 0305, 46, 2003, arxiv : hep-th / 0303194 . S. Ashok, M. Douglas: Counting flux vacua . In: JHEP , 0401, 060, 2004.