from the if-god-isn't-real-who-tricks-scientists? dept.
Scientists long believed that Earth's lower mantle was composed of Bridgmanite (Mg,Fe)SiO3 and magnesiowüstite (Mg,Fe)O, in which Fe2+ dwells. This view changed when experiments showed that Fe2+ simply can't exist at the pressure and temperature of the lower mantle. What is present is Fe3+. The two phases (Mg,Fe)SiO3 and (Mg,Fe)O both shed Fe2+ and, in turn, MgSiO3 and MgO remain. However, what mineral hosts Fe3+ had remained unknown.
Now, scientists have a possible answer: Maohokite, a newly discovered high-pressure mineral. It may be what composes the Earth's lower mantle along with Bridgmanite MgSiO3 and magnesiowüstite MgO. The study reporting this new mineral was published in Meteoritics & Planetary Science.
[...] Maohokite, with a composition of MgFe2O4, has an orthorhombic CaFe2O4-type structure. The existing mineralogical model of the Earth's mantle shows that the ferromagnesian lower mantle is mainly composed of Bridgmanite (Mg,Fe)SiO3 and magnesiowüstite (Mg,Fe)O. Therefore, the fact that Maohokite contains Mg and Fe, two major components of the lower mantle, only makes the case stronger that Maokohite is a key mineral in the lower mantle.
The researchers were under a lot of pressure to produce this result.
(Score: 0) by Anonymous Coward on Saturday December 08 2018, @09:41AM
It's made of rock.
Interesting.
(Score: -1, Flamebait) by Anonymous Coward on Saturday December 08 2018, @10:13AM (4 children)
I've grown strangely skeptical of modern science, which I've come to learn is largely based on the quasi-religious work of theoretical naval gazers.
Is this all based on assumptions about pressures, temperatures, constituent atoms, and gravity? Just because you can play with these things in the lab or, worse, in computer simulations, doesn't mean that your results actually apply to this universe.
The next paradigm shift in science will be a return to empiricism, where intrepid researchers try to document what this universe is actually doing, not what some coneheads imagine is happening.
(Score: 2) by MichaelDavidCrawford on Saturday December 08 2018, @11:20AM
Theoreticians never win the Nobel until experimentalists confirm their predictions.
For example, CERN's discovery of the Higgs resulted not in any CERN collaboration members getting the Nobel, rather it was shared three old guys who'd been waiting for their Prize since the sixties when they independently predicted the Higgs existence.
HOWEVER!
Exciting theoretical predictions make headlines all the time. This is due to a phenomenon known in Hollywood as "Feeding The Monster": you feed the entertainment industry's endless hunger for novelty by shoving scripts into its gaping maw.
Yes I Have No Bananas. [gofundme.com]
(Score: 2) by Pslytely Psycho on Saturday December 08 2018, @11:22AM
I submit that you might possibly be more dense than what comprises the mantle at those depths.
Not everything can be empirical. At some point we likely will extract samples that either confirm or falsify the theory.
Those theoretical naval gazers gave you the machine you use to browse the collected knowledge of humanity, and the collected stupidity as well. I think you defined pretty well which portion you peruse.
But never fear, your cave is near where you can hide from knowledge to your hearts content. You'll always have porntube.
Alex Jones lawyer inspires new TV series: CSI Moron Division.
(Score: 4, Informative) by AthanasiusKircher on Saturday December 08 2018, @05:20PM (1 child)
Indeed! Those idiots, like Galileo and Newton and all the rest! Quasi-religious idiots with their theories! What did they ever give us? [/sarcasm]
Well, I'm sure computer simulations may be involved. But there's a lot of empirical observation involved in making an educated guess about what the inside of the Earth likely is. We can observe how seismic waves propagate to various parts of the world, for example, which -- when we measure them in detail and analyze them -- tells us a lot about relative densities of material inside the Earth at various layers. We can observe various rocks on the Earth's surface produced by various processes and use that to come to some reasonable assumptions about the relative composition of various elements. We can look at observed percentages of elements in the universe (based on spectra), models of how stars likely age and die (based on loads of lab experiments with elements, atoms, and how they interact) to also figure out likely composition of planets with various parameters. We can look at actual output from volcanoes and such to at least give a sense of the immediate layer of material beneath the Earth's surface to test our theories. Etc., etc.
Unless you assume that the physics and chemistry of materials inside the Earth are radically different from the rest of what we can observe in labs and in the universe around us, chances are we have a pretty reasonable guess about what might be going on... all based on centuries of observations and experiments, as well as models built on them. (And please note that the summary makes clear that this is a guess based on a model -- not empirical fact -- e.g., "It may be what composes the Earth's lower mantle...")
Let's think about this a bit. Those who advocate this sort of radical "empiricism" generally never think through the consequences of what they are advocating.
First, let's note that the bedrock of modern science is actually a belief in things like mathematical modeling to make predictions -- even if such predictions are counterintuitive and, more importantly, even if we cannot observe the exact physical mechanism or situation.
This was one of the most critical shifts of the so-called "Scientific Revolution," which freed us from the authoritarian paradigm of believing in stuff like Aristotle, because it was always known to be so. Aristotle was very much an experimentalist. Most of his theories make reasonable sense given the types of experiments that could be done at the time. For example, he noticed that "elements" always seem to move toward their most natural place (e.g., air rises, earth sinks), and to a state of rest. Similar arguments say that light things should fall slower than heavier things -- look at a feather compared to an iron ball.
Galileo challenged this notion. He did experiments with ramps that suggested if one could just get rid of friction, objects in motion might go on forever. If we could get rid of the friction we now know as "air resistance," the feather and the iron ball might fall at the same rate. He extrapolated from the data at hand to create a model that suggested counterintuitive results for the time, but they were consistent with all the data he collected looking for a deeper truth.
Take a moment and think about your suggestion that we can only "document" what the universe is doing. If we never are allowed to interpolate or extrapolate based on observation, science would never progress. Imagine you are measuring the properties of a substance. "Hmm... at 32 C this material X is a solid with Y density and Z thermal conductivity. At 34 C this same material X has pretty much the same properties, though very slightly different. Measuring at every other degree above and below this range for a while, I can create a smooth curve. But what could these values be at 33 C?!?! I DON'T KNOW!! The universe hasn't told me yet! Maybe the material blows up or turns into gold or starts spitting out miniature gnomes! Okay, so I measure at 33C. What about 32.5C? I DON'T KNOW! THE UNIVERSE HASN'T BEEN OBSERVED THERE YET! Okay, so I measure 32.5C. What about 32.25C?"
Etc. One can then start questioning everything. What if the properties of this material change radically if I observe them in California vs. Florida vs. Maine? What if the properties change if they are observed next Tuesday or after the full moon or on every other Thursday before Labor Day? What if the properties change if they are observed by a woman instead of a man or by a child?
How do we have any clue about the continuity of data we collect from the universe? Well, over time, through centuries of experimental data, we've discovered that fundamental properties of elements don't seem to vary based on whether they're observed in a different location or by a different person on a different day. So, we conclude that it's a reasonable assumption that elements have similar properties in other parts of the universe (including inside the Earth). We also make reasonable assumptions like if we have a smooth curve connecting the dots of measurements for a temperature range that we can interpolate other values.
In essence, we build a model. That's what Galileo did. That's what experimentalists do, because it's the only way to make sense of out of data -- other than as a bunch of disconnected data points with no logic or connection.
Newton took things a step further. He made the conceptual leap to the idea that even if we can't observe the reason why things occur, if the math works out well as a predictive model, maybe something's there. That's where the Universal Theory of Gravitation comes from. Many scientists of the day were skeptical of Newton, because his theory relied on some sort of spooky "invisible force acting a distance," which sounded like black magic to diehard empiricists. But Newton's theory worked. It brought together a lot of disparate observations about how gravity acts on Earth and how the Solar System is organized -- things that previously seemed like they had no connection. He did this by modeling an INVISIBLE FORCE that could not be observed directly.
Pause and think about that for a second. Because that's the bedrock of modern science. Build on invisible phenomena -- but invisible phenomena that could be modeled effectively based on lots and lots of empirical data.
That's what modern science does. That's what empiricism is: it takes lots of observations and creates models from it. Whether those models are applicable in all situations or in extreme situations remains to be tested, but until they can be, that's what science works from. Newton couldn't have conceived of whether his model could predict how things would work around black holes, for example... and it turns out we needed more subtlety to physics to understand gravity at that level. But the physics that allows us to understand why gravity bends time and space in extreme circumstances also allows our GPS systems to function, for example -- because we need to make relativistic corrections to clocks far above the Earth's surface to get accurate enough measurements to navigate via GPS.
Again, all of this is modeling invisible phenomena, not susceptible to direct observation in an experiment. For the longest time, things like atoms couldn't be observed directly either -- and to the extent that there are fundamental restrictions caused by quantum phenomena, we can never truly observe some atomic and subatomic phenomena effectively in terms of "direct observation." (What counts as "observation" for your "empiricism," by the way? Do we need to see things with the naked eye? Are instruments allowed? How can we trust them?)
At some point we need to make assumptions about the continuity of nature. We may not be able to see inside the Earth or even drill down and take a sample, but using scientific models, we can make a reasonable guess about what "may" be there. The process that allows that is indeed the foundation of modern science. Such modeling may sometimes go too far, but if you don't believe in it at all, I can't see how you could even function in the world. Do you calibrate your car mirrors every morning before driving -- just to see that the fundamental laws of optics still are working in new conditions of the new day? The question of empiricism is how far the models can take us, but we all extrapolate based on models and assumptions derived from previous observation or observation under different conditions.
(Score: 0) by Anonymous Coward on Sunday December 09 2018, @04:38AM
He can't. [[[They're]]] keeping the electric universe down.
(Score: 2) by dltaylor on Saturday December 08 2018, @10:16AM
AFAIK, they use small diamond anvils and lasers to produce the pressures and temperatures presumed to exist at various layers of the mantle (the layers correspond to phase changes in the materials at various temperatures and pressures; material "A" exists within this range and material "B" exists within some other range).
How sure can they be that materials existing in the very small test cells correspond to the much more mixed and distributed environments of kilometers deep and fluid environments of the mantle?
Of course, there's an apropos XKCD: https://xkcd.com/2058/ [xkcd.com]
(Score: 2) by Pslytely Psycho on Saturday December 08 2018, @11:09AM (2 children)
"The researchers were under a lot of pressure to produce this result."
"He who would pun would pick a pocket" Dr. Stephen Maturin*
*Master and Commander: The Far Side of the World
Alex Jones lawyer inspires new TV series: CSI Moron Division.
(Score: 2) by Phoenix666 on Saturday December 08 2018, @01:47PM
he didn't even know enough to pick the lesser of two weevils.
Washington DC delenda est.
(Score: 0) by Anonymous Coward on Saturday December 08 2018, @05:43PM
"The researchers were under a lot of pressure to produce this result."
Ordinarily, I don't much like editorializing in the submission but this time I will make an exception.
(Score: 2) by MichaelDavidCrawford on Saturday December 08 2018, @11:16AM (5 children)
Take this and run with it, I just don't have the headspace to look into this at all:
Pressurize your test sample with high explosive, right next to either a curved particular accelerator such as near the business end of SLAC for its X-Ray Synchrotron Radiation, or in front of the business end of an X-Ray Laser.
You'd want to sandwich your simple between two diamonds each with flat faces.
Yes I Have No Bananas. [gofundme.com]
(Score: 2) by Runaway1956 on Saturday December 08 2018, @12:42PM (3 children)
This explains why so many people in the world are unhealthy. Essential minerals (and vitamins?) are locked up within the earth's mantle, where it is only available to the filthy rich. Just a few milligrams of this stuff in your diet would grant eternal healthy life. Or, alternatively, it would kill you.
(Score: 2) by fritsd on Saturday December 08 2018, @01:02PM (2 children)
There is a solution for us, common folk!!!1!
(1) Eat lots of spinach [wikipedia.org]
(2) Read something that makes you really, really dense.
(Score: 2) by fritsd on Saturday December 08 2018, @01:05PM (1 child)
Dietary warning: make a cheese or yoghurt sauce to bind the oxalates of the spinach to Ca, if you want to try this.
(Score: 2) by MichaelDavidCrawford on Saturday December 08 2018, @04:22PM
It happens that Monocle Polish is made by baking a blend of oxalic acid with some other chemicals.
The phosphoric acid in Coca Cola in combination with calcium rich food can give you kidneys stones.
Yes I Have No Bananas. [gofundme.com]
(Score: 2) by fritsd on Saturday December 08 2018, @12:56PM
That doesn't sound like such a bad idea: X-ray crystallography [wikipedia.org]
I don't know if you'd have enough time to observe the new position of the Mg and Fe atoms in the deformed crystal after the shockwave, before the sample container and X-ray detectors get blown up.
Also maybe it would take some time for the compound to "settle" and recrystallize, like if you melt Sulfur, the chewing gum like light brown stuff takes a short while to crystallize to β and then a longer while for that
to crystallize to the room-temperature α form (from wiki [wikipedia.org]).