The basic Galaxiki rules state that we shall stay close to the physics of the real world. This means that the universe is about 13.7 billion (13.700.000.000) years old. The Galaxiki galaxy is about 8 billion years old.

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The best current data estimates the age of the universe today as 13.7 billion years since the big bang.

Examination of small variations in the microwave background radiation provides information about the nature of the universe, including the age and composition. The age of the universe from the time of the Big Bang, according to current information provided by NASA's WMAP (Wilkinson Microwave Anisotropy Probe), is estimated to be about 13.7 billion (1.37 × 1010) years, with a margin of error of about 1 % (± 200 million years). Other methods of estimation give different ages ranging from 11 billion to 20 billion. Most of the estimates cluster in the 13–15 billion year range.

The scientific theory which describes the origin and evolution of the universe is Big Bang cosmology, which describes the expansion of space from an extremely hot and dense state of unknown characteristics. The universe underwent a rapid period of cosmic inflation that flattened out nearly all initial irregularities in the energy density; thereafter the universe expanded and became steadily cooler and less dense. Minor variations in the distribution of mass resulted in hierarchical segregation of the features that are found in the current universe; such as clusters and superclusters of galaxies. There are more than one hundred billion (1011) galaxies in the universe, each containing hundreds of billions of stars, with each star containing about 1057 atoms of hydrogen.