In cosmology empty space has an energy density ρΛ of
ρΛ=ρc⋅ΩΛ⋅c2
with ΩΛ beeing the dark energy fraction (0.683 according to Planck 2013) and ρc beeing todays critical density defined by
ρc=3H20/8/π/G
where H0=2.176⋅10−18s−1 is the Hubble constant, and G=6.674⋅10−11m3kg−1s−2 Newtons constant. This is in units of Joule/m3 or Pascal
ρΛ=5.2⋅10−10kgm−1s−2
Now the universe is expanding, and since the volume increases, so does energy. The rate at which space expands is as mentioned above 2.176⋅10−18m/m/s which means that every meter grows by 2.176⋅10−18 meters every second.
So one cubic meter, 1m3, every second gives birth to
ΔV=V2−V1=6.528⋅10−18m3
Where the volume V1 = r3 with r=1m, and V2=r⋅(1+H0⋅Δt) with Δt=1s
When we multiply the new born volume ΔV with the dark energy density ρΛ and divide it by Δt, we get in units of power, kgm2s−3, the value of
3.394⋅10−27Watt
Is my interpretation that every cubic meter generates a power of 3.394⋅10−27Watt correct, or is there a flaw in my considerations?
Answer
is there a flaw in my considerations?
For one thing, the universe is not just empty space.
But, anyways... yeah, if you have a volume of constant energy density and you increase that volume while keeping the energy density constant then... yeah, you increase the energy. It's true.
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