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Discover Magazine dark matter

Discover Magazine dark matter
Your hands are, roughly speaking, 360 million years old. Before then, they were fins, which your fishy ancestors used to swim through oceans and rivers. Once those fins sprouted digits, they could propel your salamander-like ancestors across dry land. We know a fair amount about the transition from fins to hands thanks to the moderately mad obsession of paleontologists, who venture to inhospitable places around the Arctic where the best fossils from that period of our evolution are buried. By comparing those fossils, scientists can work out the order in which the fish body was transformed into the kind seen in amphibians, reptiles, birds, and mammals–collectively known as tetrapods. A team of Spanish scientists has provided us with a glimpse of that story. Before getting into the details of the new experiment, leap back with me 450 million years ago. Our own fishy ancestors gradually modified this sort of fin over millions of years. Both fins and hands get their start in embryos.

7 Man-Made Substances that Laugh in the Face of Physics | Cracke The universe is full of weird substances like liquid metal and whatever preservative keeps Larry King alive. But mankind isn't happy to accept the weirdness of nature when we can create our own abominations of science that, due to the miracle of technology, spit in nature's face and call it retarded. That's why we came up with... #7. Ferrofluids What do you get when you suspend nanoparticles of iron compounds in a colloidal solution of water, oil and a surfactant? A ferrofluid is a liquid that reacts to magnetic fields in trippy ways that make you think that science is both magical and potentially evil. Tell us that didn't look like the birth of the most sinister dildo ever. What happens is that when a magnetic field is applied to the fluid, the particles of iron compound inside align to it. What the Hell is it Used For? #6. It's not the brick in the picture up there, it's the stuff under the brick. Every once in a while, science rules. #5.

Skeptical Science: Examining Global Warming Skepticism The Future Science - News for Your Neurons The earliest split in modern humanity was 100,000 years ago What's interesting is that as a result of this split, populations within the Khoisan group should about as much genetic diversity as the rest of humanity does combined. And that's including every other genotype within Africa. Once you eliminate the African populations from the pool it gets even narrower, to the point that the genetic differences between Eurasians, Amerinds, and Australian aborigines are remarkably small comparatively. On a related note, I remember going through the different Y-chromosome haplogroups of the world and was fascinated to find that the population group closest to Western Eurasians (including Europeans, Near Easterners, and East Indians) with Haplogroup R were the Amerinds, among whom the closely related Haplogroup Q is very common. In fact, the ancestral link through Y-chromosome between both groups appears stronger than that between East Eurasians and either of the two.

Matrix mechanics Matrix mechanics is a formulation of quantum mechanics created by Werner Heisenberg, Max Born, and Pascual Jordan in 1925. Matrix mechanics was the first conceptually autonomous and logically consistent formulation of quantum mechanics. It extended the Bohr Model by describing how the quantum jumps occur. It did so by interpreting the physical properties of particles as matrices that evolve in time. It is equivalent to the Schrödinger wave formulation of quantum mechanics, and is the basis of Dirac's bra-ket notation for the wave function. Development of matrix mechanics In 1925, Werner Heisenberg, Max Born, and Pascual Jordan formulated the matrix mechanics representation of quantum mechanics. Epiphany at Helgoland In 1925 Werner Heisenberg was working in Göttingen on the problem of calculating the spectral lines of hydrogen. "It was about three o' clock at night when the final result of the calculation lay before me. The Three Papers Heisenberg's reasoning . Further discussion Nobel Prize

RealClimate Emotiv - Brain Computer Interface Technology NeuroLogica Blog Jan 13 2017 Cognitive Biases in Health Care Decision Making This was an unexpected pleasant find in an unusual place. The Gerontological Society of America recently put out a free publication designed to educate patients about cognitive biases and heuristics and how they can adversely affect decision making about health care. The publication is aimed at older health care consumers, but the information it contains is applicable to all people and situations. What is most encouraging about this publication is the simple fact that it recognizes that this is an issue. The report is aimed simultaneously at health care providers and patients. Continue Reading » Jan 12 2017 Curcumin Hype vs Reality A recent systematic review of the alleged health benefits of curcumin show that, yet again, hype based on “traditional use” is not a reliable guide. Curcumin is a spice that makes up about 5% of turmeric, a yellow spice used in many curries. The systematic review had two main findings: Continue Reading »

Are Neanderthals Human? By Carl Zimmer Posted 09.20.12 NOVA scienceNOW In August 1856, in the German valley of Neander—Neanderthal in German—men cutting limestone for the Prussian construction industry stumbled upon some bones in a cave. Looking vaguely human, the bones—a piece of a skull, portions of limbs, and fragments of shoulder blades and ribs—eventually made their way to an anatomist in Bonn named Hermann Schaafhausen. Do Neanderthals belong within Homo sapiens? Schaafhausen pored over the fossils, observing their crests and knobs. The Neanderthal Man challenged Schaafhausen with a simple yet profound question: Was it a human, or did it belong to another species? It's been over 150 years since the bones first emerged from the Neander Valley—a time during which we've learned a vast amount about human evolution. Variations on a theme The Neander Valley bones were a sensation as soon as Schaafhausen published his report on them in 1857, because nothing like them had been seen before. European savages

museum of science, art and human perception The Intersection This is a guest post by Tim Broderick, a Chicago resident with a keen interest in science and science education. One of the most painful moments in the film “Jesus Camp” (and there are many) comes when a parent homeschooling her children talks about evolution. The kids are shown watching creationist videos mocking science, and are then led, in a lesson, to reject and question science for no other reason than for a religious fundamentalist view of the world. Contrast that with the image of a church congregation whose members join together to honestly explore their faith through exploration of science. Now, think about at least 90 congregations wanting to do that. St. As one of the instigators of those Darwin Day events, I was approached earlier this year by Rev. We put together what we felt was a pretty interesting program – looking at the Dover evolution trial, global warming, cosmology and neuroscience. And then an interesting thing happened last week. We didn’t get the grant.

Future The future is what will happen in the time period after the present. Its arrival is considered inevitable due to the existence of time and the laws of physics. Due to the apparent nature of reality and the unavoidability of the future, everything that currently exists and will exist can be categorized as either permanent, meaning that it will exist for the whole of the future, or temporary, meaning that it won't and thus will come to an end. The future and the concept of eternity have been major subjects of philosophy, religion, and science, and defining them non-controversially has consistently eluded the greatest of minds.[1] In the Occidental view, which uses a linear conception of time, the future is the portion of the projected time line that is anticipated to occur.[2] In special relativity, the future is considered absolute future, or the future light cone.[3] Future studies, or futurology, is the science, art and practice of postulating possible futures. Forecasting[edit]

Bad Astronomy Well now, this is an interesting discovery: astronomers have found what looks like a "super-Earth" – a planet more massive than Earth but still smaller than a gas giant – orbiting a nearby star at the right distance to have liquid water on it! Given that, it might – might – be Earthlike. This is pretty cool news. We’ve found planets like this before, but not very many! And it gets niftier: the planet has at least five siblings, all of which orbit its star closer than it does. Now let me be clear: this is a planet candidate; it has not yet been confirmed. The star is called HD 40307, and it’s a bit over 40 light years away (pretty close in galactic standards, but I wouldn’t want to walk there). Massive planets tug on their star harder, so they’re easier to find this way. In this case, HD 40307 was originally observed a little while back by HARPS, and three planets were found. We don’t know how big the planet is, unfortunately. That’s exciting because of the prospect for life.

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