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Universal Big Bang Lithium Deficit Confirmed
An anonymous reader writes New observations of the star cluster Messier 54 show that it is just as deficient in lithium as our own galaxy, furthering a mystery about the element's big bang origins. "Most of the light chemical element lithium now present in the Universe was produced during the Big Bang, along with hydrogen and helium, but in much smaller quantities. Astronomers can calculate quite accurately how much lithium they expect to find in the early Universe, and from this work out how much they should see in old stars. But the numbers don't match — there is about three times less lithium in stars than expected. This mystery remains unsolved, despite several decades of work."
WTF does that even mean?
I believe they meant "precisely", not "accurately". Their theories make a prediction which has error bars on it; the measurements taken have error bars on them; the error bars do not overlap.
"Astronomers can calculate quite accurately how much lithium they expect to find in the early Universe," can they? How do they know it's accurate? What control values are they using?
It's not entirely semantic, either; it goes on to say, "But the numbers don't match."
So how is that "quite accurate"?
You're being a pedant.
Let me rephrase for you: Using our current model of the big bang, scientists come up with 3x as much lithium as is measured. Therefor the model likely needs adjusting or there is something about the post big-bang that we do not quite understand.
By accurate they mean this measurement directly contradicts the model. There is no way for an error in the calculation to account for the difference.
To say you can calculate quite accurately an expected value makes no sense a all. I can only understand that they estimate the value using models and believe these models to be accurate. Any other signification is senseless and it would be pointless to argue over it.
Furthermore, you can't asses the accuracy of an estimation with a model. The model is, as you point it yourself out, what gives the estimated value. Only a measurement can validate the estimation and the model.
Their models gave prediction for the other elements and observations showed that the model was pretty much spot on. Using the same approach for Li, they assumed (or hope for) a similar accuracy. Observation now show that it wasn't the case.
But the point of the statement was that the believed it would be accurate (again, because any other interpretation of the sentence makes no sense at all). If it is not based on other results using the same model or technique, how do you believe they would have that confidence on the accuracy of their expectation?