We knew this universe was fading, but now scientists have a much clearer picture of how fast the lights are going out.Don't panic, though. There's plenty of time to get groceries, climb the Matterhorn, or whatever you have lined up for today. It looks like the 13,798,000,000 or so years since this universe began haven't even brought us to halftime.
Other scientists are pretty sure they're detecting neutrinos generated inside Earth. "Pretty sure" isn't "really sure," though, so they're still working on that research.
Right after a very quick glance at natural philosophy becoming science, I'm going to say why I do not believe that thinking is a sin — again.
You've probably read that sort of thing on this blog before, so skip ahead to Portrait of a Fading Universe, teach yourself origami, read a good book, whatever.
Science and an Odd Notion
"Science," strictly speaking, got started in Europe, as folks there were recovering from the Black Death.In earlier centuries, folks in the Islamic world had access to ancient Greek texts, and a common language: which made comparing notes a whole lot easier. Europeans were using Latin as a common language until very recently, which is why I studied Latin in high school, and that's another topic.
Alhazen was working on optics, astronomy, mathematics, meteorology, visual perception, and what we recognize as the scientific method about a thousand years ago. Meanwhile in Europe, cathedral schools became universities.
After the Black Death, folks like Nicolas Steno laid the groundwork for today's sciences, and an Irish-born Calvinist said that the universe was created in 4004 BC.
The odd notion that faith and reason, religion and science, are at war got traction during the mid-19th century; Albertus Magnus was canonized and proclaimed a Doctor of the Church in 1931, and made patron saint of natural scientists in 1941.
And that's yet another topic. Topics. (July 15, 2014; July 4, 2014; August 16, 2013)
Thinking is Not a Sin
The "Church of Danae" in Wiley Miller's Non Sequitur comic strip is fictional. The fear that there's something bad about thinking — not so much.Thinking can get a person into trouble: but so can walking or talking, depending on where a person walks and what's said.
I could 'over-think' a situation, eventually convincing myself that some bizarre product of my imagination was a practical solution.
But in that case my problem wouldn't be thinking too much: it'd be forgetting what's real and what's not.
I'm a Catholic, so I don't have to choose between faith and reason. It's faith and reason. ("Fides et Ratio," John Paul II (September 14, 1998); Catechism of the Catholic Church, 35)
I don't see a point in God giving us brains, and expecting us to not use them. But that's just me, indulging in cracker-barrel philosophy.
Happily, the Church has a growing collection of resources online; so finding what's said about an aspect of our faith is fairly easy. Most of the time.
God created a good, beautiful, and ordered world: and gave us brains. We are rational creatures, using our brains is part of what we do. (Catechism of the Catholic Church, 32, 154-159, 299)We're created in the image of God. We can, using reason, see God's work in the universe. (Catechism, 35-36, 282-289, 301, 303-306, 311, 341, 1704)
Again: thinking is not a sin, and studying this world is okay. Science and technology, learning about the universe and using that knowledge to develop new tools, is part of being human. (Wisdom 7:17; Catechism, 307, 1730, 2292-2295, 2415-2418)
Since I believe that God creates the universe, and isn't a liar, fearing knowledge of God's creation would be illogical. It's like I said last week: truth cannot contradict truth. I was quoting Pope Leo XIII:
"...God, the Creator and Ruler of all things, is also the Author of the Scriptures - and that therefore nothing can be proved either by physical science or archaeology which can really contradict the Scriptures. ... Even if the difficulty is after all not cleared up and the discrepancy seems to remain, the contest must not be abandoned; truth cannot contradict truth...."
("Providentissimus Deus,"1 Pope Leo XIII (November 18, 1893) [emphasis mine])
1. Portrait of a Fading Universe
(From ICRAR/GAMA and ESO, via BBC News, used w/o permission.)
("These pictures show a single galaxy, imaged at some of the different wavelengths in the GAMA survey"
(BBC News))
"Fading cosmos quantified in 21 colours"News that the universe is going out isn't surprising. There's only enough stuff left to keep star formation going for maybe another 1,000,000,000,000 to 100,000,000,000,000 years. After that, we'll have few billion years left before the last stars run out of fuel. (July 24, 2015)
Jonathan Webb, BBC News (August 10, 2015)
"A team of astronomers has published a multi-coloured survey of five chunks of space - and offered the best estimate yet of how fast the Universe is fading.
"They analysed the light from 200,000 galaxies in 21 wavelengths and found that the energy output of the Universe has nearly halved in two billion years.
"This agrees with previous calculations, confirming that the lights are slowly going out right across this spectrum.
"The drop is largely due to the falling rate at which new stars are formed...."
That's a lot of time. I've talked about time, perceptions, and all that, before. (August 12, 2015)
Those numbers are very approximate, by the way. These scientists said that it's too early to be very specific. That's not surprising, either.
We didn't confirm that the Andromeda galaxy is another "island universe" until 1920s. Much of what we've learned about the size and age of the universe is new since I was in high school. We have a great deal left to learn. (July 15, 2014; June 14, 2015)
Tightening the Error Bars
(Via ICRAR/GAMA, via BBC News, used w/o permisson.)
("GAMA penetrates into space in five wedge-shaped segments - here compared to the range of other major surveys"
(BBC News))
"...'The data release means that a whole lot more people outside the team are going to be able to jump on the data and do science with it, which is incredibly important,' said Dr Stephen Wilkins of the University of Sussex, another GAMA team member.Like I've said before, it's exciting when observation or experiment shows that our assumptions about how the universe works need adjustment. But it's also nice when we learn that our theories are reasonably accurate.
"He told BBC News that the strength of GAMA is that it combines so many wavelengths, where previous surveys have concentrated on a few....
"...That means they can look at light from stars that are both young and old, as well as light that has been absorbed and then re-emitted by dust. So the new assessment of the Universe's decline includes information from a huge variety of galaxies, including those hidden behind dust....
"...'It's a new spin, and it completely agrees with the previous results - but it's tightened the error bars as well.'
"Specifically, when the team totted up the total energy output of galaxies at three different ages, they saw a steady slump. In total, from 2.25 billion years ago to 0.75 billion years ago, the Universe's output apparently fell by about 40%...."
(Jonathan Webb, BBC News)
As Dr. Stephen Wilkins said, this study confirmed what scientists had found before: and "tightened the error bars."
Error bars are those little marks you see on some graphs, showing how uncertain the data is. Some uncertainty is inevitable. For example, if the smallest markings on your tape measure are 16ths of an inch, you're not likely to be accurate to within 1/64 of an inch.
GAMA (Galaxy And Mass Assembly) survey data won't make much difference in my everyday life — apart from giving me something to write about. It will keep quite a few scientists busy, though."...Dr Aprajita Verma, an astrophysicist at the University of Oxford, said GAMA offered a unique and valuable data set because of its spread of wavelengths.
" 'We know that galaxies can exhibit very different properties if you look at them purely in the visible, compared to other wavelengths,' she told the BBC. 'This study is making a census of their emissions, right the way from the UV through to the sub-millimetre range.'
"Dr Verma was also pleased the wider research community would get its hands on the data. 'It will spawn lots of new studies,' she said."
(Jonathan Webb, BBC News)
2. Hot News from IceCube Neutrino Observatory
(From Sven Lidstrom/ICECUBE/NSF, via BBC News, used w/o permission.)
("The IceCube experiment is located near the South Pole but can "look" both upward and downward"
(BBC News))
"Fastest ever neutrino among slew of fresh findings"I talked about neutrinos back in April. They're the first sort of dark matter scientists identified. We've known about them since 1956. (April 17, 2015)
Jonathan Webb, BBC News (August 7, 2015)
"Physicists have unveiled a raft of new findings about neutrinos bombarding the Earth from above, below - and within.
"An experiment built in a vast slab of Antarctic ice has doubled its count of 'cosmic neutrinos' from outer space, by searching for arrivals passing through the planet from the north.
"The same team this week announced the highest-energy neutrino ever detected.
"Meanwhile, a detector in Italy reported the first firm evidence for neutrinos produced beneath the Earth's crust.
"These 'geo-neutrinos' carry much less energy but can inform scientists about the radioactive processes generating heat inside our planet.
"The neutrinos from space, by contrast, offer clues about mysterious, violent sources of radiation beyond our own galaxy...."
Known about neutrinos, that is. We've had scientists for about a half-millennium, and natural philosophers for much longer, like I said earlier.
This IceCube data is exciting, because scientists can track the muons: zeroing in on their origin to within a half-degree. As the University of Wisconsin-Madison's Francis Halzen tolkd BBC News, "...this is totally going to change the astronomy we can do."
The "geo-neutrinos" are important, too; for scientists studying Earth's interior. I'll get back to that.
Ernie, Bert, and Tracking Cosmic Neutrinos
(From Nasa-verve, via Wikimedia Commons, used w/o permission.)
(Diagram of IceCube's core, a cubic kilometer holding thousands of sensors, nearly a mile under Antarctic ice.)
"...Neutrinos are subatomic particles with no charge and almost no mass, which very rarely interact with anything. This means they can practically cross the Universe in a straight line, passing through entire planets undeflected - and undetected.Because neutrinos have no electric charge, magnetism doesn't affect them. They have mass, probably, but it's tiny even compared to other subatomic particles. Gravity affects them, and so does the weak subatomic force, and that's about it.
"But the IceCube collaboration has laced a cubic kilometre of ice beneath the South Pole with light sensors, to record the flashes created when a neutrino very occasionally bumps into an atom....
"...In 2013 IceCube announced the first ever detection of neutrinos from outside the Solar System: 28 of the particles were caught moving at energies far beyond the reach of humanity's best particle accelerators. Since then, the count of such 'cosmic neutrinos' has climbed above 50. ..."
(Jonathan Webb, BBC News)
They're produced during radioactive decay and nuclear reactions, like what happens in our sun's core: and inside our planet.
Saying that neutrinos "...can practically cross the Universe in a straight line..." is accurate, or not: depending on how you define "straight line." Gravity affects neutrinos, which gets me into general relativity, world lines, spacetime topology, and Minkowski diagrams.
I can see why Jonathan Webb wrote "in a straight line."
Scientists named that 2013 IceCube neutrino "Ernie:" and another, spotted at about the same time, "Bert." And who says scientists don't have a sense of humor? (Apathetic Lemming of the North (November 22, 2013))
IceCube's sensors don't actually detect neutrinos. They're sensitive to Cherenkov radiation, that blue glow you'll see in water-cooled nuclear reactor cores.It's what happens when a charged particle goes through a dielectric medium faster than the speed of light in that medium. The speed of light in a vacuum is higher than in stuff like water or glass, which is why we get refraction.
The last I heard, physicists are still studying Alcubierre's math. It looks like moving part of spacetime through the rest takes a lot less power than originally thought. We're still a long way from a practical warp drive, though. Probably.
- "Warp Field Mechanics 101"
Dr. Harold "Sonny" White, NASA Johnson Space Center
(From ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110023492_2011024705.pdf (March 18, 2013)) - "Eagleworks Laboratories: Advanced Propulsion Physics Research"
Dr. Harold "Sonny" White, Paul March, Nehemiah Williams, William O'Neill NASA Johnson Space Center
(From ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110015936_2011016932.pdf) (March 18, 2013))
Getting back to the IceCube Neutrino Observatory's detector, neutrinos are electrically neutral: so they won't generate Cherenkov radiation.
When a neutrino hits something, which is rarely, it knocks charged leptons loose — electrons, muons, or taus. Those things, the IceCube sensors can detect when they make Cherenkov radiation. The sensors are more sensitive to muon effects, since they make longer tracks.
Meanwhile, on Earth - - -
(From the Borexino Collaborative, via BBC News, used w/o permission.)
("Borexino's detector is filled with a specially made hydrocarbon fluid"
(BBC News))
"...Rather than a slab of ice, the Borexino experiment buried under Gran Sasso in Italy contains 200 tonnes of specialised oil, filling an immense, spherical vat that is similarly studded with light sensors.
"Borexino was built to catch low-energy neutrinos spat out by the nuclear reaction at the heart of the Sun. And it was successful - but the international team has now used seven years' worth of data to look inside the Earth itself.
"Our planet's interior generates vast amounts of heat: about 20 times the combined output of all the world's power stations. Much of it is radioactive heat - but scientists don't know exactly how much.
"'The only way to really understand how much heat comes from radioactivity is to measure the neutrinos coming from inside,' explained Aldo Ianni, a member of the Borexino collaboration.
"Detectors like Borexino or KamLAND in Japan have glimpsed such 'geo-neutrinos' already, along with countless stray neutrinos produced by nuclear power stations right across the globe...."
(Jonathan Webb, BBC News)
KamLAND (Kamioka Liquid Scintillator Antineutrino Detector) is part of the Kamioka_Observatory near Toyama. Like the Borexino installation, the detectors are underground.That's a diagram of the KamLAND detector, originally from "Results from KamLAND reactor neutrino detection."(2005)
It's full of gripping prose like "...The reactor neutrino anomaly defined as the flux disappearance and spectrum shape
distortion is confirmed at the 99.999995% significance...."
I enjoy reading stuff like that, your experience may vary, and "KamLAND" reminds me of "Samarkand" for some reason: maybe because the names rhyme in my language. Sort of.
Anyway, Samarkand was about halfway along the Silk Road. From around 260 AD to 715 or thereabouts, folks there were Buddhists, Zoroastrians, Hindus, Manicheans, Jews, and Nestorian Christians.
Over in Europe, the Frankish kingdom was conquering folks in what's now France and Germany. Then Samarkand started getting conquered, but not by Franks. By 750, Samarkand stopped changing hands quite so often. There were survivors, happily, but the city just wasn't the same as before.
A few centuries later, Genghis Kahn happened, followed by the Black Death, and I've gotten seriously off-topic.
Where was I? Neutrinos, Italy, Japan, Samarkand, Genghis Kahn, Black Death. Right.
Scientists are pretty sure that they're tracking neutrinos generated by radioactive stuff in Earth's mantle. Dr. Aldo Ianni said that their confidence level is 98%. That's pretty good — but not good enough for this to be an official "discovery." Particle physics researchers have rules.
Those rules say that scientists have to get a 5 sigma confidence level — which does not mean watching five Doctor Who episodes featuring Ood Sigma, and I am not going to wander into that topic.
CERN writing guidelines say that 5 sigma confidence means that there's less than a one in a million chance that a 5-sigma result is wrong. That's very high confidence, indeed.
Borexino, KamLAND — Why Bother?
(From Science Photo Library, via BBC News, used w/o permission.)
("The Borexino experiment's stainless steel sphere is studded with light sensors"
(BBC News))
"...Dr Jeanne Wilson is a particle physicist at Queen Mary University of London who works on the SNO+ neutrino experiment in Canada as well as T2K in Japan. She agreed that the Borexino findings were preliminary but important.These neutrino studies are pretty close to 'pure science:' research done because we're human, and curious; with no obvious economic benefit.
" 'From previous results, we could say with good confidence that we were seeing geo-neutrinos - but the more you detect, the more information you can extract on where they're coming from.
" 'We're getting to the point now where you can start to do these analyses.'
" 'I don't think there's anything in these data that contests the models we currently have for the Earth - but they're proving that we're getting to the point where neutrinos will actually help.' "
(Jonathan Webb, BBC News)
When or if these scientists demonstrate that the phenomena they're studying really are neutrinos from Earth's mantle, it won't result in new and improved hair care products or guaranteed weight loss results. At least, I'd be more than astounded if that happened.
On the other hand, scientists who study Earth's interior will get a new research tool. Today, Geophysicists measure satellite orbits, Earth's magnetic field, seismic waves, and other phenomena to get an idea of what's going on inside our planet.
I'm pretty sure they'd be happy to have another 'window' to look through. Their research will, quite probably, help us predict earthquakes; and prepare for these events. Maybe neutrino research isn't quite so 'pure' after all. I'm okay with that.
Researching this post, I learned that the Borexino observatory is part of the Supernova Early Warning System. My part of the world gets tornadoes every summer, so I appreciate an early warning system's value. Why we need one for supernovas - - -
Eventually I'm pretty sure we'll have immediately practical reasons for a supernova early warning system. Scientists figure one of those big stellar explosions happens within 33 light years of Earth every quarter-billion years or so: on average.
Right now, though, Betelgeuse is the only star in our part of the galaxy that's likely to become a supernova 'soon:' by cosmic standards. It's likely to become a Type II supernova within the next 1,000,000 years.I've talked about Betelgeuse, science fiction's early years, and vaguely-related topics in other blogs:
- "Betelgeuse, Stellar Wind, and Exploding Eggs"
Apathetic Lemming of the North (February 8, 2013) - "Move the Planet - or - Safety First"
Drifting at the Edge of Time and Space (December 9, 2009) - "Giant Walking Houses and Other Weird Ideas From Science Fiction's Early Years"
Apathetic Lemming of the North (May 11, 2010)
Current models of what happens then say that when a star's core starts collapsing, it goes fast. The outer part of the core will be falling at about 23% of the speed of light. This heats up the core — and it gets complicated at that point.
Neutrinos are fast and 'slippery' enough to escape the collapsing core: carrying some energy with them; and giving astronomers something to study, when shock fronts of energy and particles reach them. That gets me back to the Supernova Early Warning System.
The idea is that by alerting astronomers early in a supernova's development, they can get a better look at the early stages. I gather that Borexino, Daya Bay, KamLAND, IceCube, LVD, and Super-Kamiokande, are part of the system; and that they haven't spotted anything yet.
Don't worry about Betelgeuse — it's a little under 650 light-years way, close enough to give us a good view, but far enough so that we'll be safe. Supernovae occasionally go off close to home, and that's another topic. (January 16, 2015)
More posts, mostly about science and using our brains:
- "The Universe: a Magnificent Tent"
(June 14, 2015)
Particularly - "Dark Matter and Energy: New Data, and a Map"
(April 17, 2015)
Particularly - "Large Hadron Collider: There’s More to Learn"
(April 10, 2015)
Particularly - "Humility, Science, and Accepting Reality"
(March 29, 2015)
Particularly - "Scientific Discoveries: an Invitation to 'Even Greater Admiration' "
(September 21, 2014)
Particularly
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