Amount of dark Energy at different times

In summary, the amount of dark energy in the observable universe is not well-defined and is not a useful quantity in General Relativity. However, the density of dark energy remains constant and is about one eighth of the current amount, based on the scale factor of 0.618, which corresponds to 6 billion years ago. The radius of the observable universe then was about half of what it is now.
  • #1
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I am wondering what the formula would be for the amount of Dark Energy in the observable universe would be for different time (t). (according to best current theory/data)

Would it be this directly proportional to volume?
Dark energy (t) = Dark energy (present time)/ (scale factor (t)3)

If so, 6GY ago scale factor = 1.618 therefore Dark Energy would be about 1/4 the current amount.

I could be way off as I am just starting on this stuff.
 
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  • #2
I don't think that the amount of dark energy is a useful quantity (total energy is not well-defined in General Relativity). The density, however, is useful, and can be thought of as a constant (if it does change over time, those changes haven't yet been detected).
 
  • #3
Apart from what Chalnoth said about the usefulness of total energy, the radius of the observable universe does not scale directly with scale factor a. You mentioned a=1.618, which is in the future, so I guess you intended to say a=0.618, which correlates with 6 Gy ago.
The radius of the observable universe was then about half of what it is today ( D_particle ~ 23 Gly then, according to LightCone 7) and the total vacuum energy in the observable universe about one eighth of today (at constant density).
 
  • #4
Jorrie: That clarifies what I was looking to understand. I also was not using scale factor term correctly.
Thanks
 

Related to Amount of dark Energy at different times

1. What is dark energy?

Dark energy is a theoretical form of energy that makes up about 68% of the known universe. It is believed to be responsible for the accelerating expansion of the universe.

2. How is the amount of dark energy measured at different times?

The amount of dark energy is measured through various methods such as cosmological observations, supernova surveys, and measurements of the cosmic microwave background radiation.

3. Has the amount of dark energy changed over time?

According to current theories, the amount of dark energy has remained constant throughout the history of the universe. However, this is still a topic of ongoing research and debate among scientists.

4. How does the amount of dark energy affect the expansion of the universe?

The amount of dark energy directly impacts the rate of expansion of the universe. As the amount of dark energy increases, the expansion of the universe accelerates, and vice versa.

5. Can the amount of dark energy be controlled or manipulated?

As dark energy is a theoretical concept, it cannot be controlled or manipulated in the same way as traditional forms of energy. However, further research and understanding of dark energy may lead to potential applications and technologies in the future.

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