<p>As mentioned above the density of vacuum energy in empty space is absolute constant, even as the volume of a region of space grows as the universe expands. So the total energy, density times volume, goes up.</p>

<p>More information <a href="http://www.preposterousuniverse.com/blog/2010/02/22/energy-is-not-conserved/" rel="nofollow">here</a>.</p>

CC BY-SA 3.0
2015-05-05T16:38:40.390Z
This is one model that cannot be presently ruled out. There are other models that tend towards the value we see today, but which may not have been constant in the past (or the future). These models cannot be ruled out either.
ProfRob
CC BY-SA 3.0
2014-07-09T21:14:04.007Z
2014-07-10T16:12:12.120Z
2014-07-10T16:12:12.120Z
dking
<p>Does the "amount" of dark energy in the universe change over time, or is it constant?  The dark energy I am asking about is the rate of acceleration of the universe's expansion.</p>

CC BY-SA 3.0
2014-07-09T17:07:27.893Z
In the leading model (cosmological constant), the *density* of dark energy is constant, but not for extended models with a different equation of state. Even if the density is constant, that does not mean the *total amount* of dark energy is constant--because "total amount" is not necessarily defined. Related: [Why isn't the dark energy getting decreased?](http://astronomy.stackexchange.com/questions/2042/why-isnt-the-dark-energy-getting-decreased)
Stan Liou
<expansion><cosmological-inflation><dark-energy>
Is dark energy constant?
Jonathan
# Is dark energy constant?

(Asked by: username_0 on 2014-07-09)

Does the "amount" of dark energy in the universe change over time, or is it constant? The dark energy I am asking about is the rate of acceleration of the universe's expansion.

**Tags:** expansion, cosmological-inflation, dark-energy
> **Comments:**
> **username_1**: In the leading model (cosmological constant), the *density* of dark energy is constant, but not for extended models with a different equation of state. Even if the density is constant, that does not mean the *total amount* of dark energy is constant--because "total amount" is not necessarily defined. Related: [Why isn't the dark energy getting decreased?](http://astronomy.stackexchange.com/questions/2042/why-isnt-the-dark-energy-getting-decreased)  

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## 1 answers

### Answer by username_2 on 2014-07-09. Score: 3

As mentioned above the density of vacuum energy in empty space is absolute constant, even as the volume of a region of space grows as the universe expands. So the total energy, density times volume, goes up.

More information [here](http://www.preposterousuniverse.com/blog/2010/02/22/energy-is-not-conserved/).

> **Comments:**
> **username_3**: This is one model that cannot be presently ruled out. There are other models that tend towards the value we see today, but which may not have been constant in the past (or the future). These models cannot be ruled out either.  

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