How many universes are there in the galaxy
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The Concept of Multiple Universes in the Galaxy
Observable Universe and Galaxy Count
The observable universe is vast, containing billions of galaxies, each with billions of stars. Current estimates suggest there are about 100 billion galaxies in the observable universe, with each galaxy containing roughly 100 billion stars on average3 4. This immense scale highlights the complexity and enormity of the cosmos.
Defining Universes and Observable Patches
In cosmology, the term "universe" can be interpreted in different ways. One common interpretation involves the concept of "observable universe-sized patches." Based on current cosmological models and data from the Wilkinson Microwave Anisotropy Probe (WMAP), it is estimated that there are at least 21 observable universe-sized patches similar to our own, with a potential upper limit of around 105 patches2. This suggests that while we can observe a vast portion of the universe, there may be many more regions beyond our observational capabilities.
The Role of Cosmological Models
Cosmological models consistent with General Relativity indicate that the total volume of the universe can be either finite or infinite, depending on the spatial curvature. Current data suggest that the curvature is very close to flat, which implies a lower limit on the total volume of the universe2. This flat curvature supports the idea of multiple observable patches within the universe.
Implications for the Number of Universes
The concept of multiple universes, or multiverses, extends beyond the observable universe. While we can estimate the number of observable patches, the true extent of the universe remains unknown due to limitations in our observational technology and the finite speed of light. The idea of multiverses suggests that there could be an infinite number of universes, each with its own physical laws and constants.
Conclusion
In summary, while we can estimate the number of observable universe-sized patches within our observable universe, the true number of universes remains a topic of theoretical exploration. Current cosmological models and observational data suggest a minimum of 21 observable patches, with the potential for many more beyond our current observational limits. The concept of multiple universes continues to intrigue scientists and expand our understanding of the cosmos.
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How many galaxies are in the universe?
Galaxy in the Milky Way than in the Virgo cluster, and surveys are biased towards the Milky Way, making it harder to detect distant galaxies.
HOW MANY UNIVERSES DO THERE NEED TO BE
There are at least 21 universes with the same volume as ours, but we cannot know the number of observable universes beyond 105 patches.
Hydrodynamics, Vortices and Angular Momenta of Celestial Objects
Non-irrotational hydrodynamic flow in the universe can explain the formation of large numbers of galaxies and stars, indicating a primordial rotation broken up into vortex line structures.
Gamma-Ray Emission of Active Galaxies
The observable universe consists of billions of galaxies, many of them containing 100 billion or more stars, like our “Milky Way” for example. On a morphological basis these galaxies are grouped into three main categories: spirals, ellipticals, and irregulars.
A large population of galaxies 9 to 12 billion years back in the history of the Universe
This survey reveals a large population of galaxies at 9-12 billion years back in the history of the Universe, 1.6 to 6.2 times larger than previous estimates, with vigorous star formation rates.
Astronomy with the Naked Eye
The Sun is a relatively insignificant star in a relatively insignificant galaxy, the Milky Way, and our understanding of the universe is based on the knowledge of the universe from an unprivileged point of view.
THE EVOLUTION OF GALAXY NUMBER DENSITY AT z < 8 AND ITS IMPLICATIONS
The total number of galaxies in the universe up to z = 8 is (2 trillion), a factor of 10 higher than would be seen in an all sky survey at Hubble Ultra-Deep Field depth, and this result resolves the Olbers' paradox.
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