How Does Mass Scale with Co-Moving Distance in an Expanding Universe?

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In summary, the question is asking for the mass of a world (sphere) in terms of the mass of the Hubble sphere, given a flat universe and a Lambda constant, with Hubble length as one unit and mass as one unit.
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uri friedberg
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I will be thankful if you could solve my puzzle regarding universe expansion.
Considering a flat universe, Lambda constant.
If we shall denote Hubble length (Radius) as one unit, and mass equal to one unit.
What is the mass of a world (sphere) with co-moving distance equal to 3.3 Hubble length (Particle Horizon) in terms of the mass of Hubble sphere,
and the mass of a world with co-moving distance of 4.5 (The size of the universe we shall ever see) in terms of the mass of Hubble sphere,
Appreciate your time and kindness (Is the mass just the rario of lengths to the cube?).
Uri Friedberg
 
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The mass of a world with a co-moving distance equal to 3.3 Hubble lengths (the particle horizon) is equal to (3.3)^3 times the mass of the Hubble sphere. The mass of a world with a co-moving distance equal to 4.5 (the size of the universe we will ever see) is equal to (4.5)^3 times the mass of the Hubble sphere.
 

1. What is the concept of universe expansion?

The concept of universe expansion is based on the observation that galaxies in our universe are moving away from each other. This means that the space between galaxies is increasing, causing the overall size of the universe to expand. This expansion is believed to have started with the Big Bang, the event that is thought to have created our universe.

2. How do we know that the universe is expanding?

Scientists have observed the expansion of the universe through various methods, including measuring the redshift of galaxies, studying the cosmic microwave background radiation, and monitoring the brightness of distant supernovae. These observations all support the idea that the universe is expanding and has been doing so since the beginning of time.

3. What is dark energy and how does it relate to universe expansion?

Dark energy is a mysterious force that is thought to be responsible for the acceleration of universe expansion. It makes up about 70% of the total energy density of the universe and its exact nature is still not fully understood. However, its effects on the expansion of the universe can be observed through its influence on the motions of galaxies.

4. Will the universe continue to expand forever?

Based on current observations and theories, it is believed that the universe will continue to expand forever. This is because the amount of dark energy in the universe is expected to remain constant or even increase over time, causing the expansion to accelerate. However, new discoveries and advancements in science may change our understanding of the fate of the universe.

5. How does the expansion of the universe affect the objects within it?

The expansion of the universe does not directly affect objects within it, such as planets, stars, and galaxies. This is because the force of gravity between these objects holds them together, counteracting the effects of expansion. However, the increasing distance between objects due to expansion means that in the distant future, other galaxies may become too far away to be observed by us here on Earth.

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