As far as I understand, the projected age of the universe is about 99.5% of the estimated "Hubble time". The age is projected by applying a correction factor to the inverse Hubble constant. The correction factor applied depends on the value of the cosmological constant. The constant is derived from WMAP observation data, and valued at 0.976. For a flat universe without cosmological constant, the value would have been 0.666, resulting in a projected age 66.6% of the Hubble time.
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The age of the universe is approximately 13.8 billion years, while the Hubble time is around 20.8 billion years. The ratio of the age of the universe to the Hubble time is about 66.3%, not 66.6%. This ratio is due to the expansion rate of the universe changing over time, affecting the relationship between the two quantities.
Hubble's discovery of the expanding universe in the 1920s provided evidence against the static universe model favored at the time, which relied on a cosmological constant to maintain stability. By observing that galaxies were moving away from each other and the universe was expanding, Hubble's findings contradicted the need for a cosmological constant to explain a static cosmos.
Edwin Hubble did not invent the telescope. He was an astronomer who used telescopes to make significant discoveries, such as the expansion of the universe. The telescope has been around for centuries before Hubble's time.
Expansion, run in reverse, is contraction. The universe gets larger as it moves into the future, and smaller as we examine its past. If we go back to the time when the expansion originally began, which was the Big Bang, the universe was very small, perhaps only the size of a proton, or even a singularity of zero volume.
The best supporting evidence that the universe is expanding is that galaxies are receding from one another, indicating that the universe is expanding over time. This observation is based on the redshift of galaxies, known as Hubble's Law.
The Hubble Space Telescope has been in space for over 31 years, since its launch on April 24, 1990. It has made numerous groundbreaking discoveries and has revolutionized our understanding of the universe.