Solar Neutrinos and Answers
The New York Times has today published a story announcing that Scientists have finally identified the "missing neutrinos" that have been sought since the 1960s, when the theory of atomic fusion predicted that large quantities of neutrinos should be being emitted by the Sun. Since then, only a third as many neutrinos as theory demanded have been detected. Naturally, creationists have fallen upon this "gap" between the observation and the theory as a convenient wedge to drive into the validity of astrophysics as a whole.
As an example, my first quote is from Andrew Snelling, in an article from the AiG web site titled Solar Neutrinos - the Critical Shortfall Still Elusive.
He goes on about the atomic physics associated with the Sun, discusses the "missing neutrinos" issue, and even mentions the theory that has now been given a strong boost about where they are (see the text of the NY Times article below). However, at the end he discards this theory to use the opportunity to say this ...
So, after 10 years, no one has yet explained all the data on neutrinos. Of course there's one explanation not considered - perhaps the reason for the critical shortfall is that nuclear reactions are not solely responsible for producing the Sun's energy. But such an explanation would be tantamount to an admission that we really don't yet know how the Sun operates, which would clearly be embarrassing. And if we don't understand how our nearest star operates, how can the astronomers be so sure how all the other stars 'evolved' and now operate? As candidly admitted by David Malin, head research scientist at the Anglo-Australian Telescope, in a recent interview on Australian ABC radio, 'How little we really know!'"
Which is like saying "we haven't yet incorporated Gravity into a Grand Unified Theory of Physics, so it would be best not to believe it just yet". I have sent an e-mail to Professor David Malin at the Anglo Australian Telescope to ask him if he believes he has been misquoted in this article (go here for my e-mail to Professor Malin and his reply).
The next quote is from Jonathan Sarfati, in an article titled The Sun: our special star which was published in Creation Ex Nihilo (22(1):2730 December 1999 February 2000).
How does the sun shine?
In 1939, Hans Bethe proposed that the sun and other stars are powered by nuclear fusion ... That fusion is responsible for at least part of the sun's energy output is supported by the sun's huge flux of neutrinos, ghostly particles that can usually pass through light-years thicknesses of matter untouched.
However, if nuclear fusion were the sole source of power, then we would expect to observe three times more neutrinos than we do. This shortfall has been tentatively explained by the idea that neutrinos alternate between three types. This would require that they have mass, although previously they were universally regarded as massless.
Alternatively, two-thirds of the sun's energy could be provided by gravitational collapse, through conversion of gravitational potential energy to heat and light as the sun's gases collapse inwards. This theory was proposed by the great physicist Hermann von Helmholtz (1821-1894). It was the chief theory until the prominence of Darwinism, which could not tolerate that it would put an upper limit on the sun's age at 22 million years - far too short for evolution. Observations suggesting the sun is shrinking at a rate of at least 0.02 seconds of arc per century, give some support to the notion.10 This would be ample for collapse to be a significant energy source. But the shrinkage is controversial, even among creationists. In any case, since nuclear fusion is at least a partial source of energy, Helmholtz's age limit cannot be strictly applied.
However, the solar astronomer John Eddy commented:
I suspect ... that the sun is 4.5 billion years old. However, given some new and unexpected results to the contrary, and some time for some frantic recalculations and theoretical readjustment, I suspect that we could live with Bishop Ussher's value for the age of the Earth and Sun [about 6,000 years]. I don't think there is much in the way of observational evidence to conflict with that.'
This is of note because of the fact that Safarti, too, mentions the possibility of the missing Neutrinos being result of the "transformation" between electron Neutrinos and other, less detectable types such as Muon and Tau Neutrinos. However he, also, demurs in order to push the line that gravitational contraction is an equally valid theory to account for the Sun's luminosity. Gravitational contraction is a theory that was quite acceptable in the 19th Century, but has been comprehensively discredited since the early 20th century (see The Solar FAQ: Solar Neutrinos and Other Solar Oddities for an expansive look at this topic). And yet, Safarti was pushing this claim in the year 2000!
I take this as a classic example of Creationists continuing to use disproven arguments for years beyond the time they are abandoned (even by other Creationists!), for the sake of placing yet one more seed of doubt (unlikely to be researched by the average parishioner) into the minds of Christians. I think that this new evidence warrants the topic being revisited.
Here's the text of the NY Times article:
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June 19, 2001
Sun's Missing Neutrinos: Hidden in Plain Sight
By KENNETH CHANG
After three decades of searching, physicists have tracked down subatomic particles that have eluded them for 30 years. The particles, it turns out, were right there all the while but had hidden themselves as if by magic.
"We've solved a 30-year-old puzzle of the missing neutrinos of the Sun," said Dr. Arthur B. McDonald, director of the Sudbury Neutrino Observatory, near Sudbury, Ontario. In doing so, though, the researchers have answered questions about neutrino behavior and the fate of the universe.
Neutrinos are ghostly particles, one of the fundamental building blocks of the universe, like quarks, electrons and photons. Billions of them, produced by fusion reactions within the Sun, fly through every person every second. Minuscule and devoid of electric charge, though, they pass unnoticed. In fact, they are practically undetectable.
In 1968, Dr. John Bahcall, an astrophysicist at the Institute for Advanced Study at Princeton, N.J., calculated that the rate of neutrinos from the Sun passing through one square inch of area should be about 30 million a second.
Experiments beginning in the 1970's counted much lower rates; more than half of the expected neutrinos were never seen. Dr. Bahcall's predictions, refined over the years, remained unchanged.
Yesterday, scientists at the Sudbury Neutrino Observatory announced the first experimental evidence that provides a solution.
During the neutrinos' 93-million- mile journey from the Sun to the Earth, the researchers said, about two-thirds change into other varieties that are more difficult to detect.
The total number of neutrinos from the Sun, they conclude, is about 35 million per square inch per second. "The agreement is pretty good between the predictions and the measurement," said Dr. Joshua R. Klein, a professor of physics at the University of Pennsylvania who coordinated the analysis of the data.
Dr. Bahcall was ecstatic.
"I feel very much like the way I expect that these prisoners that are sentenced for life do when a D.N.A. test proves they're not guilty," Dr. Bahcall said. "For 33 years, people have called into question my calculations on the Sun."
The new finding "shows the calculations were correct," he said. "I feel like dancing," he added.
Less happy is Dr. David O. Caldwell, an emeritus professor of physics at the University of California at Santa Barbara. "My personal reaction is one of great disappointment," Dr. Caldwell said. "I was hoping for a rather different result." The data ran contrary to his hopes of finding a new kind of neutrino.
Still, he said, the Sudbury results look "quite solid."
Neutrinos come in three types (physicists call them flavors): electron neutrinos, muon neutrinos and tau neutrinos, named according to the subatomic particles they usually associate with. Muon and tau particles are heavier particles that otherwise act like electrons. The neutrinos produced by the Sun are all electron neutrinos.
Spotting the rare occasions when a neutrino collides with another particle requires large quantities of material for the neutrinos collide with.
The detector in the Sudbury Neutrino Observatory consists of a 40- foot-wide acrylic sphere containing 1,000 tons of heavy water, in which the two hydrogen atoms of the water molecules have been replaced with deuterium atoms, a heavier version of hydrogen. The sphere is submerged within a 10-story cavity that was carved out of a nickel mine 1 1/4 miles underground and filled with 40,000 tons of ordinary water.
Occasionally, an electron neutrino will slam into one of the deuterium atoms in the heavy water, splitting it into a proton and a neutron. Detectors around the sphere of heavy water are able to spot the debris. The other two types of neutrinos cannot break up deuterium. The scientists have seen 1,169 such collisions since the experiment began in 1999.
The researchers compared their results with earlier neutrino counts from the Super-Kamiokande neutrino experiment in Japan, which primarily detects collisions between electron neutrinos and electrons. But muon and tau neutrinos can also occasionally bounce off electrons.
If all the neutrinos reaching Earth from the Sun were of the electron variety, then the neutrino rates measured by Super-Kamiokande and Sudbury should match up. But Super- Kamiokande detected more. Since the Sun produces only electron neutrinos - the production of muon and tau neutrinos require higher-energy events, like matter falling into black holes or an exploding star - that means some of them must change into muon or tau neutrinos.
"It's the first direct evidence for the changing of solar neutrinos from electron type to another type," Dr. Klein said. Most physicists had considered neutrino morphing to be the most likely explanation for the missing neutrinos.
Dr. Caldwell's theory was that the electron neutrinos were changing into "sterile" neutrinos that did not interact with ordinary matter. "It looks like they've done a very thorough job," he said. "It then is a real question if there is any room for a sterile neutrino. I don't see much hope for it right now."
According to the equations of particle physics, for this transformation of flavors to occur, at least one of the neutrino types must possess a smidgeon of mass. Coupled with earlier experimental results, the researchers conclude that each of the three neutrino flavors weigh, at most, one- 60,000th as much as an electron.
But the universe is filled with more neutrinos than any other known type of particle, and some physicists have wondered whether the collective gravitation pull of neutrinos may be strong enough to stop the outward expansion of the universe and pull it back into a big crunch.
At the upper limit, the mass of neutrinos may be substantial, perhaps as much as the rest of ordinary matter, but far short of the amount needed to collapse the universe.
Most of the mass of the universe is believed to be in "dark matter," a still unknown form of matter.
For particle physicists, the neutrino data is one more piece that they will need to incorporate into a future unified theory of physics that describes the behavior of all particles and forces. The current standard model does not predict the masses of neutrinos, but its equations are simpler if neutrinos have no mass.
Now scientists know the behavior of neutrinos is not simple. Neutrinos are "very schizophrenic," Dr. Bahcall said. Still unknown, for example, is whether the electron neutrinos are changing into muon neutrinos or tau neutrinos or both.
"I expect to be up late at night trying to answer that question," Dr. Bahcall said. "It's pointing us in a way - in the right way, we hope - to make a better theory, a more encompassing theory."