The readable posts of widely read cosmologist Ethan Siegel can be read at forbes.com and realclearscience.com. Siegel sometimes makes extremely dubious statements about the Big Bang, the universe's sudden origin in a hot dense state. Contrary to what has been maintained by his fellow cosmologists for decades, who have always spoke of the Big Bang as being the very beginning of the universe, happening at Time Zero, Siegel has again and again tried to redefine the Big Bang as something that came after the beginning, after a period of exponential expansion called "cosmic inflation" (as he does in his most recent post). There is evidence that the universe suddenly began in a hot, incredibly dense state, something like the Big Bang, but there is no observational evidence for such a period of exponential expansion called cosmic inflation. There is no scientific basis for claiming that the Big Bang occurred at any time after the very beginning, but only evidence that something like the Big Bang occurred at the very beginning of the universe.
Siegel has claimed that the Big Bang theory of the universe's origin has a wonderful record of predictive success. In an over-enthusiastic article entitled "CONFIRMED: The Last Great Prediction of the Big Bang!" Siegel refers to predictions of the Big Bang theory, speaking as if they were all successful. He states this: "Each one of these predictions, like a uniformly expanding Universe whose expansion rate was faster in the past, a solid prediction for the relative abundances of the light elements hydrogen, helium-4, deuterium, helium-3 and lithium, and most famously, the structure and properties of galaxy clusters and filaments on the largest scales, and the existence of the leftover glow from the Big Bang — the cosmic microwave background — has been borne out over time."
But the claim he makes about a successful prediction of lithium abundances is not at all correct, according to many other cosmologists, who say that the Big Bang theory does not correctly predict the amount of lithium we observe in the universe. In fact, they tell us the Big Bang theory predicts the universe should have three times more lithium than it actually has. This shortfall is called the cosmological lithium problem. A university press release tells us, "The standard models of the Big Bang that are currently used predict an abundance of Li-7, the main lithium isotope, which is three or four times more than that determined via astronomical observations."
Last month a paper by two scientists stated the following (using the symbol 7Li to refer to the main lithium isotope):
"Assuming the best numerical value for the cosmic baryonic density and the existence of three neutrino flavors, standard big bang nucleosynthesis is a parameter-free model. It is important to assess if the observed primordial abundances can be reproduced by simulations. Numerous studies have shown that the simulations overpredict the primordial 7Li abundance by a factor of ≈ 3 compared to the observations."
The authors tried hard to search for some nuclear physics solution, using some computer search algorithm. But they came up empty-handed. They report their gloomy result as follows:
"We employ a genetic algorithm to search for simultaneous rate changes in these four reactions that may account for all observed primordial abundances. When the search is performed for reaction rate ranges that are much wider than recently reported uncertainties, no acceptable solutions are found. Based on the currently available evidence, we conclude that it is highly unlikely for the cosmological lithium problem to have a nuclear physics solution."
So the Big Bang theory does not correctly predict the amount of lithium in our universe, failing by a factor of 300%. This is not at all the biggest failure of the Big Bang theory. Its biggest failure is that it predicts the universe should consist of equal amounts of matter and antimatter. We know from experiments in particle accelerators that when two high-energy photons collide at very high speeds, they produce matter and antimatter in equal amounts. In the first instants of the Big Bang, the universe should have consisted of such high-energy photons, colliding with each other constantly, leaving equal amounts of matter and antimatter. A web page of the leading particle physics organization CERN starts out by saying, "The Big Bang should have created equal amounts of matter and antimatter in the early universe." But it is known that the amount of matter in the universe is actually at least 10,000 times greater than the amount of antimatter in the universe. If even a tiny bit of antimatter came into contact with some matter here on our planet, it would create an explosion vastly bigger than a hydrogen bomb explosion.
There are other cases in which prevailing scientific theories have failed to predict the current distribution of elements in the universe. A recent article at the Daily Galaxy site tells us that current theories fail to correctly predict the amount of gold and silver that we observe in the universe.
Scientists claim that the Big Bang produced only the four simplest elements: hydrogen, helium, beryllium and lithium. They explain the origin of some more complex elements such as carbon and oxygen by appealing to effects inside stars, such as supernova explosions. That gets you up to elements with 8 protons in their nucleus:
Hydrogen: 1 proton in nucleus
Helium: 2 protons in nucleus
Lithium: 3 protons in nucleus
Beryllium: 4 protons in nucleus
Boron: 5 protons in nucleus
Carbon: 6 protons in nucleus
Nitrogen: 7 protons in nucleus
Oxygen: 8 protons in nucleus
But what about much more complex elements, such as gold? Each gold atom has 79 protons in its nucleus. The Daily Galaxy article tells us that the explanation for atoms of such complexity has been one of colliding neutron stars. Such an explanation sounds very fishy. We know that neutron stars (consisting of incredibly dense matter) can form when a large star explodes in a supernova explosion. But stars are so far apart (and neutron stars so uncommon) that colliding neutron stars should be a very rare phenomenon. The number of neutron stars in our galaxy has been estimated as only 2000.
We read the following:
“ 'Neutron star mergers did not produce enough heavy elements in the early life of the universe, and they still don’t now, 14 billion years later,' said Karakas. 'The universe didn’t make them fast enough to account for their presence in very ancient stars, and, overall, there are simply not enough collisions going on to account for the abundance of these elements around today.' Instead, the researchers found that heavy elements needed to be created by an entirely different sort of stellar phenomenon—unusual supernovae that collapse while spinning at high speed and generating strong magnetic fields. The finding is one of several to emerge from their research, which has just been published in the Astrophysical Journal. Their study is the first time that the stellar origins of all naturally occurring elements from carbon to uranium have been calculated from first principles."
But be very suspicious when scientists tell you that the previous explanation they were giving you was wrong, and that there's some new explanation -- particularly when the new explanation appeals to something as seemingly farfetched and unlikely as the old explanation. "Unusual supernovae that collapse while spinning at high speed and generating strong magnetic fields" does not sound like a very plausible mechanism for generating gold. And the theorists concede that their new theory falls short in predicting the correct abundances of gold and silver. In the Daily Galaxy article, we merely read the scientists stating, "Silver is over-produced but gold is under-produced in the model compared with observations. " But looking up the relevant paper by these scientists, I find a more specific confession, where they state this: "We find that silver is overproduced by a factor of 6, while gold is underproduced a factor of 5 in the model." Oops, it sounds like our scientists are still failing to predict correctly the universe's element abundances:
Lithium: off by 300%.
Silver: off by 600%.
Gold: off by 500%.
Also, referring to a problem with predictions regarding the abundance of phosphorus in the universe, an article last month in the journal Nature told us, "There still remain strong contradictions between the nucleosynthesis models available and the chemical abundance pattern observed in P-rich stars." It seems that our scientists can't explain very well the abundances of elements in our universe or the ratio of matter and antimatter in our universe.
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