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Naty, I'm glad you saw the scroll bar and worked that out.
Just in case you are curious. the 73% we are always seeing is not a CONSTANT. It is a temporary figure that gives a handle on Lambda that depends on present conditions. Here is how to get it from the Hubble times 13.9 and 16.3 billion years.
Just calculate the ratio of their squares: 13.92/16.32 = .73
13.9 billion years is information about the present, it is 1/Ho the reciprocal of the current fractional rate of distance expansion.
16.3 billion years is the corresponding thing way out in the future. THAT is the cosmological constant, in essence.
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People who talk about Lambda as if it were a curvature that arises from a certain dark "energy" do not normally tell you what actual energy DENSITY it corresponds to in real terms like nanojoules per cubic meter. Normally they only tell you the temporarily valid handle 73%.
But I'll tell you how to get your hands on that energy density, in metric, just from the 16.3 figure.
[Footnote: If you know metric units you know that nanojoules per cubic meter is the same unit as nanopascal which is easier to say. N/m2 =Nm/m3 = J/m3 because a Joule is a Newton-meter of work.]
Take the reciprocal of 16.3, square it, and multiply by 161 nanopascals.
That gives you the energy density people think corresponds to the cosmological constant.
"16.3^-2 * 161 nanopascal"
To use the google calculator, paste 16.3^-2 * 161 nanopascal into the window.
It will do the arithmetic and tell you 6.06 x 10-10 pascals.
Which is 0.606 nanopascal.
That, precisely, is the constant energy density which people who imagine there is "dark energy" must think fills all of space. About 3/5 of a nanojoule per cubic meter.
But so far, all we have evidence for is a constant curvature term Lambda (the square of a reciprocal length) that appears in the Einstein equation, and improves the fit.
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