２８−１−１ Superstring theory and Brane cosmology
・In superstring theory we have 11-dimensional spacetime. (Dimensions that exceeds the 4-dimension are extra dimensions)
・Superstring theory suggests that the Big Bang there was many times. In other words, the universe is the multi instead of one, so that there are parallel universe.
• In the parallel universe, the laws of physics are different, but superstring theory's seems applicable.
・Since all particles except graviton can not be separated from braneworld, it is not possible to replace the substances. 
・Graviton is to travel the extra dimensions, so parallel universe(braneworld) each other can communicate using a gravity wave. 
• In this theory, it has assumed the collision of braneworlds and anti-braneworlds . 
２８−１−２ Inflation theory and multiple occurrence of universe (multi-production of universe)  
・1982 Katsuhiko Sato other recommendations
・Many mini-universe are produced from a unitary universe.
・Mini-universe are completely detached from its parent universe.
• To make the child the universe there is a need to take inflation artificially.
• It is made possible by making a large area of highly vacuum energy in the universe.
・However, there is a need to pull heat well.
・Since vacuum energy remains slightly in the current universe, it can be expected that multi-universe is born naturally when vacuum energy undergoes a phase transition.
２８−１−３ Real universe and Imaginary universe：Structure of the universe☆(2015)
・If the universe (the Real universe) including the Milky Way galaxy was born from a quantum fluctuation, the universe (the Imaginary universe) including quantum fluctuations is assumed on the outside.
・In the Imaginary universe it can be estimated to exist other universe(Parallel universe) born from quantum fluctuations.
☆From the birth of the Real universe to Big Bang
• If the quantum fluctuation does not exceed the threshold, the resulting pair of substance and antimatter within the fluctuation disappears. = The Real universe is not born.
• When the quantum fluctuation exceeds a threshold value, the symmetry of matter and anti-matter brakes, and antimatter is to rapidly expand the space-time after 1e-36 seconds. ( The size of the Real universe (1e-27m) is much smaller than atom (1e-10m) ⇒3 millimeters (1e-3m): The Inflation: inflation rate is 60-fold of light speed.)
(In the reverse case, the Real universe is not born because space-time collapses.)
- Immediately after that, (1e-36 seconds after → 1e-32 seconds after) substance of high temperature causes the Big Bang.
(The size of the Real universe : 3 mm (1e-3m) ⇒10cm (1e-1m))
☆Future of the Real universe
- The Real universe will evaporate at the end of continuing expansion. = Disappearance of the result of a large fluctuation that occurred in the Imaginary universe
• Before evaporation, the outer shell of antimatter in the Real universe will become brittle, and if it conflicts with other parallel universe, both universe will collapse.
・That is, if the matter that was scattered by the collision of the other two parallel universes collides with the outer shell of the Real universe, we might be able to measure it in quantum.
２８−２ Multiverse and Anthropic principle 
・In most multiverse, human beings are not born.
・・・Even if just a little different from the electromagnetic force and the strong force of the four forces of nature, there is no fact that carbon is synthesized in the interior of the star.
・・・In the four-dimensional universe, because gravity and electromagnetic force is inversely proportional to the cube of the distance, the structure of galaxies and planetary systems or the structure of the atom becomes unstable.
・In other words・・・
・This universe is beautifully designed as if it was trying to present human. : Anthropic principle
２８−３ Communication between the parallel universes
・In M-theory, it has to be capable of interacting with other universe through gravity.  
 Space.com／”5 Reasons We May Live in a Multiverse”20121207
「気が遠くなる未来の宇宙のはなし(The story of the future of the universe mind-boggling)」Ktsuhiko Sato(2013)
 Michio Kaku / New York incandescent classroom " amazing prophecy of "Theory of Everything;TOE"" 20150403
 Multi-production of universes by first-order phase transition of a vacuum
 Wikipedia：Anthropic principle
 LISA Project Office