Einstein discovered that general covariance allows his GR equation to have just TWO gravitational/geometric constants: Newton G and a curvature constant he called Lambda. So the symmetry of the theory requires us to put both constants into the equation and investigate empirically whether or not Lambda is zero (in which case we could say there was just one constant after all )(adsbygoogle = window.adsbygoogle || []).push({});

With the passage of some years, the cosmological curvature constant was at last finally measured and turned out not to be zero.What is its value?If you want, that is, to write it as an actual constant of nature, not as a changing percentage on some sliding scale, but as an actual constant.

Well the curvature in question, as appearing in the Einstein equation, is a reciprocal area. One very convenient way to express length in GR context is in lightseconds, or if no confusion can arise, inseconds. And it's convenient as well, if we want to use a metric unit, to express area in

square seconds.So curvature, in that context, can be an inverse square second (s^{-2}) quantity.

Now when Planck mission recently measured this tiny curvature constant Lambda it just happened to turn out to be

1.007 x 10^{-35}seconds^{-2}

This, it must be confessed, immediately calls to mind the irreverent notion that the Creator likes powers of ten, perhaps He has ten fingers and wears a wristwatch with a second hand.

That would explain the number 1, and the 10^{-35}, in this profoundly important physical constant. But what accounts for the .007? Some secret agency, no doubt.

So how does this relate to the history of the universe that you see in one of Jorrie's tables, like this?

[tex]{\scriptsize \begin{array}{|c|c|}\hline R_{0} (Gly) & R_{∞} (Gly) & S_{eq} & H_{0} & \Omega_\Lambda & \Omega_m\\ \hline 14.4&17.3&3400&67.92&0.693&0.307\\ \hline \end{array}}[/tex] [tex]{\scriptsize \begin{array}{|c|c|} \hline S&a&T (Gy)&R (Gly)&D (Gly)&D_{then}(Gly)&D_{hor}(Gly)&V_{now} (c)&V_{then} (c) \\ \hline 10.900&0.092&0.479&0.720333&31.375&2.878&4.391&2.179&3.996\\ \hline 8.584&0.116&0.686&1.030150&29.384&3.423&5.344&2.041&3.323\\ \hline 6.760&0.148&0.982&1.471721&27.142&4.015&6.454&1.885&2.728\\ \hline 5.324&0.188&1.404&2.098399&24.621&4.625&7.722&1.710&2.204\\ \hline 4.192&0.239&2.005&2.980242&21.797&5.199&9.132&1.514&1.745\\ \hline 3.302&0.303&2.855&4.200217&18.648&5.648&10.642&1.295&1.345\\ \hline 2.600&0.385&4.044&5.833312&15.177&5.837&12.179&1.054&1.001\\ \hline 2.048&0.488&5.676&7.890822&11.427&5.581&13.633&0.794&0.707\\ \hline 1.612&0.620&7.837&10.231592&7.510&4.658&14.882&0.522&0.455\\ \hline 1.270&0.788&10.560&12.525003&3.620&2.851&15.835&0.251&0.228\\ \hline 1.000&1.000&13.787&14.399932&0.000&0.000&16.472&0.000&0.000\\ \hline 0.794&1.259&17.257&15.648602&3.109&3.914&16.842&0.216&0.250\\ \hline 0.631&1.585&20.956&16.410335&5.731&9.083&17.047&0.398&0.554\\ \hline 0.501&1.995&24.789&16.836447&7.890&15.743&17.153&0.548&0.935\\ \hline 0.398&2.512&28.694&17.063037&9.638&24.210&17.204&0.669&1.419\\ \hline 0.316&3.162&32.638&17.180008&11.040&34.912&17.224&0.767&2.032\\ \hline 0.251&3.981&36.601&17.239540&12.160&48.409&17.240&0.844&2.808\\ \hline 0.200&5.012&40.575&17.269607&13.051&65.411&17.270&0.906&3.788\\ \hline 0.158&6.310&44.553&17.284732&13.760&86.821&17.285&0.956&5.023\\ \hline 0.126&7.943&48.534&17.292324&14.324&113.777&17.292&0.995&6.580\\ \hline 0.100&10.000&52.516&17.296130&14.772&147.715&17.296&1.026&8.540\\ \hline \end{array}}[/tex]

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# James Bond and the true value of the cosmological curvature constant

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