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We decoded NASA’s messages to aliens by hand - YouTube
In 1977, twin golden records were sent into space on the Voyager 1 and 2 spacecraft. Still sailing through space at nearly 60,000 km per hour, the records…
video  earth  image  information  engineering  decode  programming  science 
february 2019 by aries1988
We may finally know what causes Alzheimer’s – and how to stop it

Multiple teams have been researching Porphyromonas gingivalis, the main bacterium involved in gum disease, which is a known risk factor for Alzheimer’s. So far, teams have found that P. gingivalis invades and inflames brain regions affected by Alzheimer’s; that gum infections can worsen symptoms in mice genetically engineered to have Alzheimer’s; and that it can cause Alzheimer’s-like brain inflammation, neural damage and amyloid plaques in healthy mice.
teeth  inflammation  brain  alzheimer  research  medicine  pharma  future  health  science  senior  bacteria 
february 2019 by aries1988
Turbulence, the oldest unsolved problem in physics

because our understanding of turbulence over time has stayed largely ad-hoc and limited, the development of technology that interacts significantly with fluid flows has long been forced to be conservative and incremental. If only we became masters of this ubiquitous phenomenon of nature, these technologies might be free to evolve in more imaginative directions.

Motions of fluids are usually hidden to the senses except at the interface between fluids that have different optical properties.

For example, you can see the swirls and eddies on the surface of a flowing creek but not the patterns of motion beneath the surface.

The Navier-Stokes equation is difficult to solve because it is nonlinear. This word is thrown around quite a bit, but here it means something specific. You can build up a complicated solution to a linear equation by adding up many simple solutions. An example you may be aware of is sound: the equation for sound waves is linear, so you can build up a complex sound by adding together many simple sounds of different frequencies (harmonics). Elementary quantum mechanics is also linear; the Schrödinger equation allows you to add together solutions to find a new solution.

The idea is that the interesting dynamics occur at larger scales, and grid points are placed to cover these. But the subgrid motions that happen between the gridpoints mainly just dissipate energy, or turn motion into heat, so don’t need to be tracked in detail. This approach is also called large-eddy simulation (LES), the term eddy standing in for a flow feature at a particular length scale.

The idea is that, while the low-speed solution is valid at any speed, near a critical speed another solution also becomes valid, and nature prefers that second, more complex solution. In other words, the simple solution has become unstable and is replaced by a second one. As the speed is ramped up further, each solution gives way to a more complicated one, until we arrive at the chaotic flow we call turbulence.
turbulence  Physics  science  history  explained  example  LES 
december 2018 by aries1988
Why fake miniatures depicting Islamic science are everywhere | Aeon Essays
With these ideals in mind, do the ends justify the means? Using a reproduction or fake to draw attention to the rich and oft-overlooked intellectual legacy of the Middle East and South Asia might be a small price to pay for widening the circle of cross-cultural curiosity. If the material remains of the science do not exist, or don’t fit the narrative we wish to construct, then maybe it’s acceptable to imaginatively reconstruct them. Faced with the gap between our scant knowledge of the actual intellectual endeavours of bygone Muslims, and the imagined Islamic past upon which we’ve laid our weighty expectations, we indulge in the ‘freedom’ to recreate.
museum  fake  muslim  science  history  opinion 
october 2018 by aries1988
振动频率大于 189Hz 为“生”瓜

振动频率 160Hz - 189Hz 为“适熟”瓜

振动频率 133Hz - 160Hz 为“熟”瓜

振动频率小于 133Hz 为“过熟”瓜

事情到这一步,应该已经差不多了,然而作者作为一个丝毫没有音乐细胞根本听不出来声音频率大小的人依旧很绝望,决定在手机上下载一个 FFT(快速傅里叶变换) 的软件,帮我来判断这个西瓜的音调到底有多高。
watermelon  science  howto  vibration 
august 2018 by aries1988
Meet the pirate queen making academic papers free online
She cared less about the form than the function: she wanted a global brain. To her, paywalls began to seem like the plaques in an Alzheimer’s-riddled mind, clogging up the flow of information.
academia  stans  story  science  piracy  female  leader  russia  today  idea  world  brain  knowledge  share 
february 2018 by aries1988
异乡人——雷立柏:东西方的对话不只有手机和高铁,还有孔子和柏拉图|一周精选|深度|异乡人|端传媒 Initium Media
gaijin  beijing  latin  language  study  greek  science  history 
february 2018 by aries1988
How many dimensions are there, and what do they do to reality? – Margaret Wertheim | Aeon Essays

Yet the notion that we inhabit a space with any mathematical structure is a radical innovation of Western culture, necessitating an overthrow of long-held beliefs about the nature of reality. Although the birth of modern science is often discussed as a transition to a mechanistic account of nature, arguably more important – and certainly more enduring – is the transformation it entrained in our conception of space as a geometrical construct.

What is so extraordinary here is that, while philosophers and proto-scientists were cautiously challenging Aristotelian precepts about space, artists cut a radical swathe through this intellectual territory by appealing to the senses. In a very literal fashion, perspectival representation was a form of virtual reality that, like today’s VR games, aimed to give viewers the illusion that they had been transported into geometrically coherent and psychologically convincing other worlds.

In Newton’s world picture, matter moves through space in time under the influence of natural forces, particularly gravity. Space, time, matter and force are distinct categories of reality. With special relativity, Einstein demonstrated that space and time were unified, thus reducing the fundamental physical categories from four to three: spacetime, matter and force. General relativity takes a further step by enfolding the force of gravity into the structure of spacetime itself. Seen from a 4D perspective, gravity is just an artifact of the shape of space.

General relativity says that this warping is what a heavy object, such as the Sun, does to spacetime, and the aberration from Cartesian perfection of the space itself gives rise to the phenomenon we experience as gravity.

Whereas in Newton’s physics, gravity comes out of nowhere, in Einstein’s it arises naturally from the inherent geometry of a four-dimensional manifold; in places where the manifold stretches most, or deviates most from Cartesian regularity, gravity feels stronger. This is sometimes referred to as ‘rubber-sheet physics’. Here, the vast cosmic force holding planets in orbit around stars, and stars in orbit around galaxies, is nothing more than a side-effect of warped space. Gravity is literally geometry in action.

Aristotle was right – there are indeed logical problems with the notion of extended space. For all the extraordinary successes of relativity, we know that its description of space cannot be the final one because at the quantum level it breaks down. For the past half-century, physicists have been trying without success to unite their understanding of space at the cosmological scale with what they observe at the quantum scale, and increasingly it seems that such a synthesis could require radical new physics.

Like Newton’s world picture, Einstein’s makes space the primary grounding of being, the arena in which all things happen. Yet at very tiny scales, where quantum properties dominate, the laws of physics reveal that space, as we are used to thinking about it, might not exist.
physics  dimension  maths  future  science 
january 2018 by aries1988
Hans Rosling, physician and statistician, 1948-2017

Rosling, who has died aged 68, was the closest thing statisticians had to a rock star. His most famous talk, 2006’s The Best Stats You’ve Ever Seen, has been watched online more than 11m times. Its ambitious scope and sweeping narrative epitomised Rosling’s ability to rise above the ebb and flow of current affairs and see generational trends.

It led him to conclude that on most measures of human progress — the impact of climate change being a notable exception — most countries were improving rapidly.

Public perceptions had not kept up with the pace of economic and demographic development and much of the media was hobbled by its adherence to false balance, he said. The world is discussed in terms of feelings and ideologies rather than as an area of knowledge, he once told the Financial Times.
leader  statistics  communication  science  world  data  debate  politics  ideology  optimism  explained  population 
december 2017 by aries1988
Warning of 'ecological Armageddon' after dramatic plunge in insect numbers
Three-quarters of flying insects in nature reserves across Germany have vanished in 25 years, with serious implications for all life on Earth, scientists say
environment  entomology  crisis  science  research  numbers  earth  europe 
october 2017 by aries1988
Why Land on the Moon? - The Atlantic
THOUGHTFUL critics, concerned over the allocation of limited national resources, ask whether this is a good way in which to spend funds that might otherwise be used for the betterment of man's lot on the surface of the earth. Could some of the money going into space research be diverted into other programs of public interest -- medical research, education, housing, technical aid to emerging nations -- a variety of projects contributing to the welfare of our society?

But if space money cannot readily be rerouted into other channels, that negative consideration in itself is not a reason for these large expenditures. What are the positive values which we derive from this investment?

The current discussion of these values of the space program has served the United States well in directing its attention to questions of national purpose. But, however we may try to break the program down into its elements and to attempt a detailed balancing of debits and credits, the fact remains that the space effort is greater than the sum of its parts. It is a great adventure and a great enterprise, not only for the United States but for all humanity. We have the power and resources to play a leading role in this effort, and it is inconceivable that we should stand aside.
science  politics  policy  discovery  state  moon  astronomy  nasa  space 
october 2017 by aries1988
On epigenetics: we need both Darwin’s and Lamarck’s theories | Aeon Essays
One problem with Darwin’s theory is that, while species do evolve more adaptive traits (called phenotypes by biologists), the rate of random DNA sequence mutation turns out to be too slow to explain many of the changes observed.

To quote the prominent evolutionary biologist Jonathan B L Bard, who was paraphrasing T S Eliot: ‘Between the phenotype and genotype falls the shadow.’

In evolution and biomedicine, the rates of phenotypic trait divergence is far more rapid than the rate of genetic variation and mutation – but why?

Waddington recognised the potential impact his discovery could have on the theory of evolution: the single-generation change in the fruit-fly wings were supportive of the original ideas of the heretic Lamarck. It appeared that the environment could directly impact traits.

the vast majority of environmental factors cannot directly alter the molecular sequence of DNA, they do regulate a host of epigenetic mechanisms that regulate how DNA functions – turning the expression of genes up or down, or dictating how proteins, the products of our genes, are expressed in cells.

Today, that is the precise definition of epigenetics: the molecular factors that regulate how DNA functions and what genes are turned on or off, independent of the DNA sequence itself.

epigenetic inheritance does not follow many of the Mendelian rules that apply to classic genetics and the neo-Darwinian theory of evolution. These rules hold that DNA sequences and genes function discretely, like particles; upon reproduction, the ‘particles’ from each parent unite at random with a matching pair from the other parent, leading to a new DNA sequence and new expression of inherited traits.

In conclusion, exposure to the fungicide permanently altered the descendant’s sperm epigenetics; that, in turn, led to inheritance of sexual selection characteristics known to reduce the frequency with which their genes might propagate in the broader population and directly influence evolution on a micro-evolutionary scale.
biology  evolution  theory  epigenetics  science  debate  scientist  history 
september 2017 by aries1988
The Jujitsu Master Turning an Ancient Art Into a Modern Science
Slight young men, they developed a system that relied on leverage rather than size or strength. Wrestling and judo prized pinning or throwing an opponent on his back. The Gracies realized that, in a real fight, the opposite is often more effective—control from behind, ideally with the opponent belly-down, so that he can be strangled into submission.

The sport has evolved technically as well, spawning hundreds, even thousands, of potential moves and countermoves. (The human body in motion is a complicated thing, and two of them in antagonistic combination exponentially more so.)

He rarely wears a coat in winter, which he explains by invoking the decimating French retreat of 1812: “If Napoleon’s troops could walk three and a half months through one of the worst Russian winters in history, in summer clothing, and a significant number of them returned, we shouldn’t have any problem.”
martial-arts  brazil  leader  idea  innovation  reportage  science 
july 2017 by aries1988
Tracing the Origins of Indo-European Languages
A study suggests that the Indo-European family of languages originated in Anatolia, or modern-day Turkey.
language  history  science  europe  infographics 
july 2017 by aries1988
Thomas Pesquet : « Quand on aperçoit l’ISS, c’est “Star Wars” ! »

la pollution atmosphérique – je n’ai jamais pu prendre une photo de Pékin, par exemple. Voir tout cela, non plus seulement l’intellectualiser, ça change quelque chose.

L’aviation, l’espace, étaient-ils vos rêves de gamin ?

Quand j’avais 4 ans, c’est un de mes premiers souvenirs, mon père m’avait fabriqué un vaisseau spatial avec des cartons. Il avait placé des coussins dedans, un manche et un cadran sur le rabat. J’y ai passé du temps, dans ma navette spatiale en carton, jusqu’à ce qu’elle parte à la poubelle parce que je ne voulais pas venir manger…

Plus tard, avec mon frère, on allait à la maison de la presse acheter des magazines d’aviation. J’adorais les posters avec des « écorchés » d’avion, on détaillait leur structure, on avait tous les éléments, ça faisait un peu comme les Lego Technic. Toute mon adolescence, j’ai continué à lire, à regarder des films sur l’aviation, mais je n’ai jamais pris l’avion et je ne connaissais personne dans ce milieu.
story  astronaut  français  children  science  family  school  education 
june 2017 by aries1988
Comment le Sahara nourrit la Méditerranée
« A chaque arrêt, l’eau sera récupérée et mise dans des mésocosmes [réservoirs recréant les conditions d’un milieu naturel]. On augmentera la température de 2 degrés ainsi que la teneur en CO2 pour voir comment le phytoplancton réagit. De cette manière, nous recréons les conditions que nous aurons en 2100 », résume Karine ­Desboeufs. Malgré un appui ­météo au sol, le Pourquoi-Pas ? n’a aucune garantie de croiser la route d’une pluie de poussières sahariennes. En cas de malchance, la campagne ne sera pas vaine pour autant. Des appareils de ­mesure enregistreront simultanément les paramètres chimiques, physiques et biologiques de l’air et des eaux de surface. La comparaison des données permettra de ­rechercher les interactions.
mediterranean  europe  research  science  atmosphere  sea  biology 
may 2017 by aries1988
Pourquoi est-on plus à l’aise pour dire des grossièretés dans une langue étrangère ?

De nombreuses personnes plurilingues décrivent en effet l’impression de ressentir moins de choses dans leur seconde langue, qui ne porte pas le même « poids émotionnel » que la langue maternelle. En se sentant moins lié émotionnellement à la langue que l’on parle, on peut plus facilement jurer et/ou raconter des détails de sa vie intime. Le terme scientifique pour cela est « résonance émotionnelle réduite du langage », nous apprend Wilhelmiia Toivo.

La chercheuse cite le philosophe du langage Ludwig Wittgenstein, qui disait : « Les limites de mon langage signifient les limites de mon propre monde.

une époque où le bilinguisme ne se résume pas à parler les deux langues transmises par des parents bilingues. Le bilinguisme décrit aussi la pratique de deux langues au quotidien, peu importe son degré de maîtrise, en raison d’une migration, d’un séjour à l’étranger, ou d’un échange universitaire. « Alors que le nombre de personnes changeant de langue régulièrement continue d’augmenter, comprendre tous les aspects du langage et comment il influe sur nos vies est essentiel », conclut-elle.
language  psychology  brain  science 
march 2017 by aries1988
Money and our minds: can neuroscience stop counterfeiting?

In my final presentation to the bank, I put forward evidence that the watermark on a euro should be a face instead of a building. Why? Because the human brain is massively specialised for faces, but has little neural real estate devoted to edifices. As forged watermarks are generally hand-drawn, it would be much easier to spot an imperfect face than an imperfect building.

Unfortunately, the bank faced an implementation challenge. How could they get all the different countries to agree on one person’s face? What nationality could they choose? They finally selected the mythological princess Europa, and the new €50 note with her face rolls out in April.

I then recommended all euro banknotes should be the same size, the way American bills are. That at least would get people to look at them a bit longer to see what they’re dealing with. Unfortunately, the council replied, this would require re-tooling all European vending machines. Too much work. What was my next recommendation?
money  science  design  crime  euro 
march 2017 by aries1988
李约瑟对李约瑟难题的回答 -上海书评-东方早报网







civ  china  comparison  europe  history  science  religion  book  critic  chinese  theory  research  question  debate 
january 2017 by aries1988
Joel Mokyr: Progress Isn't Natural - The Atlantic
How and why did the modern world and its unprecedented prosperity begin? Many bookshelves are full of learned tomes by historians, economists, political philosophers and other erudite scholars with endless explanations. One way of looking at the question is by examining something basic, and arguably essential: the emergence of a belief in the usefulness of progress.

This was a departure from the beliefs of most societies in the past, which were usually given to some measure of “ancestor worship”—the belief that all wisdom had been revealed to earlier sages and that to learn anything one should peruse their writings and find the answer in their pages.
essay  human  history  technology  science  knowledge  development 
november 2016 by aries1988
How science goes wrong | The Economist
Conversely, failures to prove a hypothesis are rarely even offered for publication, let alone accepted. “Negative results” now account for only 14% of published papers, down from 30% in 1990. Yet knowing what is false is as important to science as knowing what is true. The failure to report failures means that researchers waste money and effort exploring blind alleys already investigated by other scientists.
science  explained  crisis  truth  scientist  ethic 
november 2016 by aries1988
真正有《十万个为什么》色彩的“问答体”书面作品,是 16 世纪宗教改革运动以来的基督教要理(Catechism),即用来教导学生学习基本教义和圣礼的纲要性文件。1529 年,马丁·路德发表《大要理》和《小要理》,前者是针对牧师、教师和成人信众的教学手册,后者则面向被他们教导的群众,用问答形式宣传教义。

history  china  book  children  encyclopedia  kid  1960s  mao  chinese  science  education  moi 
october 2016 by aries1988
The 100 best nonfiction books: No 21 – The Structure of Scientific Revolutions by Thomas S Kuhn (1962)
The American physicist and philosopher of science coined the phrase ‘paradigm shift’
science  history  Physics 
july 2016 by aries1988
The Search for 'Earth Proxima'
A short film about a team of scientists and their mission to build a powerful telescope to explore exoplanets.
science  scientist  astronomy  earth  planet  cosmos 
july 2016 by aries1988
Fish School Us on Wind Power - Issue 37: Currents - Nautilus
As an undergraduate, Dabiri modeled the undulating movements of jellyfish. A decade later, he was involved in the construction of a medusoid—a synthetic jellyfish made from elastic silicone and the heart cells of a rat—that swims just like a living jelly when a pulsating electric field is applied.5 During that time, Dabiri also became fascinated with another unorthodox combination: schooling fish and wind power.

Fish position themselves in a staggered formation in order to use the turbulence created by their neighbors to swim more efficiently.Courtesy of Robert Whittlesey

Dabiri and Whittlesey don’t know exactly why turbines packed into closely positioned pairs are the most efficient, but they have a couple of working theories.

allows the turbine pairs to be packed more closely together—only four diameters apart compared to a norm of 15 diameters for horizontal-axis wind turbines
cfd  wind  energy  design  science  scientist  aerodynamics  ocean  moi  wt  instapaper_favs 
july 2016 by aries1988
Hazard lines
Exposure to any potential hazard involves a certain risk. It’s where we draw the line between high risk and low risk that defines what is safe and what is not. This gives rise to an interesting set of questions. Would everyone draw that line in the same place? Would we draw the same line for ourselves as we would for others? And, would we allow others to draw the line for us?

it’s well-documented that people have difficulty conceptualising ratios and fractions because they focus on numerators to the detriment of denominators, there’s been little movement away from using ratio metrics when presenting risk to the public.
nuclear  safety  science  people  perception  history  regulation  law  future  self 
june 2016 by aries1988
Why so much science research is flawed – and what to do about it
Some fields of research are less susceptible than others, though. In astronomy, chemistry and physics, for instance, people have a very strong tradition of sharing data, and of using common databases like big telescopes or high energy physical experiments, Ioannidis says. They are very cautious about making claims that eventually will be refuted. But in fields where such checks and balances are absent, irreproducible results are rife.
science  academia  data  debate  ethic  scientist 
april 2016 by aries1988
Here's the Physics Behind That Insane Chinese Traffic Jam
Or at toll points on mega-highways when not enough booths are open, forcing 50 lanes jam-packed with cars — 50 lanes? WTF, China?!? —to merge down to 20.
from:rss  fun  science  traffic 
october 2015 by aries1988
A Dying Young Woman’s Hope in Cryonics and a Future
Cancer claimed Kim Suozzi at age 23, but she chose to have her brain preserved with the dream that neuroscience might one day revive her mind.
death  brain  science  medicine  future  mind 
september 2015 by aries1988
Science Isn’t Broken
Instead, you can think of the p-value as an index of surprise. How surprising would these results be if you assumed your hypothesis was false?

Researchers often make these calls as they go, and often there’s no obviously correct way to proceed, which makes it tempting to try different things until you get the result you’re looking for.

They’re just falling prey to natural human biases that lead them to tip the scales and set up studies to produce false-positive results.

What makes science so powerful is that it’s self-correcting — sure, false findings get published, but eventually new studies come along to overturn them, and the truth is revealed. At least, that’s how it’s supposed to work.

Science is not a magic wand that turns everything it touches to truth. Instead, science operates as a procedure of uncertainty reduction, said Nosek, of the Center for Open Science. The goal is to get less wrong over time. This concept is fundamental — whatever we know now is only our best approximation of the truth. We can never presume to have everything right.

As a society, our stories about how science works are also prone to error. The standard way of thinking about the scientific method is: ask a question, do a study, get an answer. But this notion is vastly oversimplified. A more common path to truth looks like this: ask a question, do a study, get a partial or ambiguous answer, then do another study, and then do another to keep testing potential hypotheses and homing in on a more complete answer. Human fallibilities send the scientific process hurtling in fits, starts and misdirections instead of in a straight line from question to truth.

The uncertainty inherent in science doesn’t mean that we can’t use it to make important policies or decisions. It just means that we should remain cautious and adopt a mindset that’s open to changing course if new data arises. We should make the best decisions we can with the current evidence and take care not to lose sight of its strength and degree of certainty.
science  scientist  opinion  research  mind  human  people  truth  instapaper_favs 
august 2015 by aries1988
Human nature: Being scientific - New Scientist
Crucially, this understanding allows us to use what we have learned in one domain to make causal predictions in another – so, for example, we can predict that something that goes "bam!" will sink, whereas something that goes "click" may well float. Our nimbleness at abstract causal reasoning is tied up with our facility with language and probably underlies many of our other social skills, such as rituals and rules of behaviour, too. Povinelli believes this is what really sets humans apart from even the brightest apes.
science  discovery  nature  animal  comparison  analysis 
august 2015 by aries1988
It Is, in Fact, Rocket Science -
The myth of the finches obscures the qualities that were really responsible for Darwin’s success: the grit to formulate his theory and gather evidence for it; the creativity to seek signs of evolution in existing animals, rather than, as others did, in the fossil record; and the open-mindedness to drop his belief in creationism when the evidence against it piled up.

Of the tale of Newton and the apple, the historian Richard S. Westfall wrote, “The story vulgarizes universal gravitation by treating it as a bright idea ... A bright idea cannot shape a scientific tradition.” Science is just not that simple and it is not that easy.

Even if we are not scientists, every day we are challenged to make judgments and decisions about technical matters like vaccinations, financial investments, diet supplements and, of course, global warming. If our discourse on such topics is to be intelligent and productive, we need to dip below the surface and grapple with the complex underlying issues. The myths can seduce one into believing there is an easier path, one that doesn’t require such hard work.

But even beyond issues of science, there is a broader lesson to learn, and that was the crux of my reply to my daughter. We all run into difficult problems in life, and we will be happier and more successful if we appreciate that the answers often aren’t quick, or easy.
scientist  science  opinion  story  fiction  truth 
may 2015 by aries1988
Seeking Stars, Finding Creationism
Galileo knew he would have the Church to contend with after he aimed his telescope at the skies over Padua and found mountains on the moon and more moons…

Opposition to the Mauna Kea observatories, which are run by scientists from 11 countries, has been going on for years and is tied inseparably with lingering hostility over colonization and the United States’ annexation of Hawaii in the 19th century. The new telescope is a pawn in a long, losing game.

It’s bad for science, but good (I suppose) for the Native American groups involved, he wrote in an email. Given that the U.S.A. was founded on two great sins — genocide of Native Americans and slavery of Africans — I think science can afford this act of contrition and reparation.
story  tradition  astronomy  science  indigenous  hawai 
may 2015 by aries1988
Our Cosmic Selves -
That discovery is relatively recent. Four astrophysicists developed the idea in a landmark paper published in 1957. They argued that almost all the elements in the periodic table were cooked up over time through nuclear reactions inside stars — rather than in the first instants of the Big Bang, as previously thought. The stuff of life, in other words, arose in places and times somewhat more accessible to our telescopic investigations.

Since most of us spend our lives confined to a narrow strip near Earth’s surface, we tend to think of the cosmos as a lofty, empyrean realm far beyond our reach and relevance. We forget that only a thin sliver of atmosphere separates us from the rest of the universe.

Up to half the water on our planet is older than the solar system itself. Ancient water molecules assembled in the chilly confines of a gigantic gas cloud. That cloud spawned our sun and the planets that orbit it — and somehow those ancient water molecules survived the perils of the planetary birth process to end up in our oceans and, presumably, our bodies.

Together, these findings raise the odds that life’s building blocks were concocted in space and blended into the material that formed Earth and its planetary siblings.

Amid the material comforts and the relentless distractions of modern life, the universe at large may appear remote, intangible and irrelevant, especially to those of us who are city dwellers. But the next time you catch a glimpse of the Milky Way in its true glory, from a dark outpost far from city lights, think of those countless stars as nuclear factories and the starless hazy patches as molecular breweries. It is not much of a stretch to imagine the inchoate seeds of life emerging in the distance.
life  cosmos  science  origin 
april 2015 by aries1988
Is a Climate Disaster Inevitable?
The physicist Enrico Fermi first formulated this question, now called the Fermi paradox, in 1950. But in the intervening decades, humanity has recognized that our own climb up the ladder of technological sophistication comes with a heavy price. From climate change to resource depletion, our evolution into a globe-spanning industrial culture is forcing us through the narrow bottleneck of a sustainability crisis. In the wake of this realization, new and sobering answers to Fermi’s question now seem possible.
science  scifi  future  civ  earth  space  climate 
january 2015 by aries1988
Can science prove the existence of God? — Starts With A Bang! — Medium
In other words, life is a fantastic bet, but intelligent life may not be. And that’s according to reasonable scientific estimates, but it assumes we’re being honest about our uncertainties here, too. So the conditions for life are definitely everywhere, but life itself could be common or rare, and what we consider intelligent life could be common, rare or practically non-existent in our galaxy. As science finds out more, we’ll learn more about that.

The truths of the Universe are written out there, on the Universe itself, and are accessible to us all through the process of inquiry. To allow an uncertain faith to stand in as an answer where scientific knowledge is required does us all a disservice; the illusion of knowledge — or reaching a conclusion before obtaining the evidence — is a poor substitute for what we might actually come to learn, if only we ask the right questions. Science can never prove or disprove the existence of God, but if we use our beliefs as an excuse to draw conclusions that scientifically, we’re not ready for, we run the grave risk of depriving ourselves of what we might have come to truly learn.
science  religion  cosmos  life 
january 2015 by aries1988
科学圈怎么吐槽《星际穿越》? | 科学人 | 果壳网 科技有意思


吸积盘发出的光在我们看来其实是不对称的:因为灼热气体环绕黑洞的速度太快,所以假如图中气体俯视是逆时针旋转,那么左边的气体会向我们飞来,而右边的气体则会离我们而去。这张图只显示了相对论性射束效应(亮暗变化),没有显示多普勒效应(红蓝变化)。图片来源:Chris Reynolds
movie  critic  science  astro 
november 2014 by aries1988
Rosetta, une réussite européenne
En 1981, la décision unilatérale de la NASA d’arrêter sa participation à la mission ISPM de survol des pôles du Soleil par un satellite américain et un européen provoqua une crise politique majeure et vint renforcer une croissante volonté d’autonomie renforcée par le succès du premier lancement d’Ariane en 1979.

Après une large consultation de plus de 2 000 scientifiques européens, l’ESA établit, en 1984, un programme de vingt ans, « Horizon 2000 », composé de pierres angulaires, choisies par consensus de tous les scientifiques, représentant les domaines phares de leurs intérêts : observation du Soleil et de son influence sur l’environnement ; astronomie des hautes énergies et du rayonnement infrarouge lointain ; exploration des comètes et des astéroïdes concrétisée par les missions Soho et Cluster, XMM-Newton, Herschel et Planck, Giotto et Rosetta.

Conçu pour être autonome, le programme répondait à la volonté d’indépendance, tout en permettant la participation de partenaires non européens. Son coût total avoisinait 4,5 milliards d’euros sur vingt ans en exigeant une augmentation régulière du budget scientifique de l’ESA – en stagnation depuis 1971 – au niveau annuel de 27 millions d’euros, soit un dixième du programme équivalent à la NASA.

Succès politique majeur, dont Rosetta est l’illustration scientifique spectaculaire. Sa mise en œuvre exigeait une discipline de contrôle des coûts des missions. Son acceptation enclencha une révolution des méthodes de travail tant de la communauté scientifique que de l’ESA et de ses Etats membres. Le programme devint une référence européenne et internationale. Une fois accepté, il attisa l’intérêt des Américains, des Japonais, des Russes et, plus tard, des Chinois. L’Europe offrait et ne mendiait plus !
europe  space  science  engineering  comparison 
november 2014 by aries1988
How Building a Black Hole for Interstellar Led to an Amazing Scientific Discovery | WIRED
Thorne sent his answers to Franklin in the form of heavily researched memos. Pages long, deeply sourced, and covered in equations, they were more like scientific journal articles than anything else. Franklin’s team wrote new rendering software based on these equations and spun up a wormhole. The result was extraordinary. It was like a crystal ball reflecting the universe, a spherical hole in spacetime.

Some individual frames took up to 100 hours to render, the computation overtaxed by the bendy bits of distortion caused by an Einsteinian effect called gravitational lensing. In the end the movie brushed up against 800 terabytes of data. I thought we might cross the petabyte threshold on this one, von Tunzelmann says.
movie  science 
november 2014 by aries1988
Sciences en marche joue de la tête et des jambes
« Au fond, on n’a pas de revendication précise, on va sur la route, on parle aux gens, on leur dit que la France n’a pas de vision stratégique sur la recherche fondamentale. En général, ils comprennent très bien », déclare Patrick Lemaire.
science  reportage  france  academia  manif  crisis  scientist 
november 2014 by aries1988
Un « mur » qui discipline les ondes
« C’est une très belle idée », ­confirme Ping Sheng, de l’université de Science et Technologie de Hongkong. Lui-même songe à la développer, avec l’équipe de l’Institut Langevin, pour les ondes acoustiques. Dans une pièce bruyante, une personne pourrait alors parler à une autre, à l’autre extrémité, comme si elles étaient voisines.
engineering  science 
october 2014 by aries1988
Le Nobel de chimie récompense l’invention de « nanoscopes »
Alors qu'un microscope classique voit des cellules ou des bactéries, les nouvelles techniques développées par les lauréats depuis le milieu des années 1990 permettent de voir des virus, des protéines, les pelotes d'ADN, la dynamique de la machinerie moléculaire au cœur des cellules… Pour marquer la transition, certains parlent désormais de " nanoscopie ". D'autres techniques avaient précédemment atteint de telles précisions mais seulement sur des surfaces et non dans des environnements biologiques.
science  future  invention  today  biology 
october 2014 by aries1988
The Odds, Continually Updated -
By contrast, Bayesian calculations go straight for the probability of the hypothesis, factoring in not just the data from the coin-toss experiment but any other relevant information — including whether you’ve previously seen your friend use a weighted coin.

Scientists who have learned Bayesian statistics often marvel that it propels them through a different kind of scientific reasoning than they’d experienced using classical methods.

“Statistics sounds like this dry, technical subject, but it draws on deep philosophical debates about the nature of reality,” said the Princeton University astrophysicist Edwin Turner, who has witnessed a widespread conversion to Bayesian thinking in his field over the last 15 years.

One downside of Bayesian statistics is that it requires prior information — and often scientists need to start with a guess or estimate. Assigning numbers to subjective judgments is “like fingernails on a chalkboard,” said physicist Kyle Cranmer, who helped develop a frequentist technique to identify the latest new subatomic particle — the Higgs boson.

A famously counterintuitive puzzle that lends itself to a Bayesian approach is the Monty Hall problem, in which Mr. Hall, longtime host of the game show “Let’s Make a Deal,” hides a car behind one of three doors and a goat behind each of the other two. The contestant picks Door No. 1, but before opening it, Mr. Hall opens Door No. 2 to reveal a goat. Should the contestant stick with No. 1 or switch to No. 3, or does it matter?

A Bayesian calculation would start with one-third odds that any given door hides the car, then update that knowledge with the new data: Door No. 2 had a goat. The odds that the contestant guessed right — that the car is behind No. 1 — remain one in three. Thus, the odds that she guessed wrong are two in three. And if she guessed wrong, the car must be behind Door No. 3. So she should indeed switch.
explained  statistics  science  scientist  today 
october 2014 by aries1988
The Way to Beat Poverty
A study by Ann Streissguth at the University of Washington found that by age 14, 60 percent of children born with fetal alcohol syndrome or effects have been suspended from school or expelled. Almost half have displayed inappropriate sexual behavior such as public masturbation.

The licking and grooming seemed to affect the development of brain structures that regulate stress. A rat’s early life in a lab is highly stressful (especially when scientists are picking up the pups and handling them), leading to the release of stress hormones such as cortisol. In the rats with less attentive mothers, the cortisol shaped their brains to prepare for a life of danger and stress. But the attentive mothers used their maternal licking and grooming to soothe their pups immediately, dispersing the cortisol and leaving their brains unaffected.
parenting  usa  science  opinion 
september 2014 by aries1988
Sabine Lisicki, record serve: Science explains why female tennis players can serve as fast as men.
This selection effect creates a surfeit of female talent in a small number of sports. The world’s top women’s tennis players, particularly the Williams sisters, are likely among the best female athletes alive. The best male athletes, by contrast, aren’t concentrated in a particular sport—they might play basketball or soccer or football or run track, depending on their country of origin, socioeconomic status, and any number of other factors.
sports  explained  science 
september 2014 by aries1988



science  story  biology  philosophy 
september 2014 by aries1988
Is Every Speed Limit Too Low?
Every year, traffic engineers review the speed limit on thousands of stretches of road and highway. Most are reviewed by a member of the state’s Department of Transportation, often along with a member of the state police, as is the case in Michigan. In each case, the “survey team” has a clear approach: they want to set the speed limit so that 15% of drivers exceed it and 85% of drivers drive at or below the speed limit. In its 1992 report, the U.S. Department of Transportation cautioned, “Arbitrary, unrealistic and nonuniform speed limits have created a socially acceptable disregard for speed limits.” Lt. Megge has worked on roads with a compliance rate of nearly zero percent, and a common complaint among those given traffic citations is that they were speeding no more than anyone else. With higher speed limits, Megge says, police officers could focus their resources on what really matters: drunk drivers, people who don’t wear seat belts, drivers who run red lights, and, most importantly, the smaller number of drivers who actually speed at an unreasonable rate.
people  behavior  traffic  opinion  driving  law  science 
august 2014 by aries1988
为什么中国学者搞科研,却要写成英文的论文发表? - 知乎日报
from:rss  explained  science 
august 2014 by aries1988
How to crack improbability and win the lottery – David Hand – Aeon
This distinction – between the chance that you (or, indeed, any other particular person) will win the lottery and that someone will win – is a manifestation of what I call the law of truly large numbers. If a large enough number of people each buy a lottery ticket, then the probability that someone will win becomes substantial. It grows so large, indeed, that someone wins almost every week.

If you win the lottery one week with a one-in-14-million chance per ticket, then your chances of winning it the next week are unaltered. Statisticians say that the two events are independent, but another way to put it is that the lottery numbers don’t remember who has won previously: the outcome of one draw doesn’t affect the following one.

The same does not hold for the Titanic. For if one compartment is damaged so that it floods, what does that say about the probability that a neighbouring compartment might also be damaged? Well, clearly our answer depends how the damage occurs. As it happens, the Titanic’s maiden voyage was through iceberg-infested waters. If an iceberg were to strike the side of the ship penetrating the double hull, isn’t there a good chance that it would also damage neighbouring compartments?

We live in a complex world, and the different components of a system are often locked in a web of interconnections that are difficult to tease apart. When trying to make sense of them, it is common to assume independence as a first approximation. But this can lead to major miscalculations. The Yale sociologist Charles Perrow has developed an entire theory of what he calls ‘normal accidents’, based on the observation that complex systems should be expected to have complex, undetected, interactions. A frightening thought.
probability  maths  science  explained  disaster 
june 2014 by aries1988
Volcanoes? Meteors? No, the worst mass extinction in history could have been caused by microbes having sex - The Times of India
They believe that the sudden acquisition of a new set of genes enabled methane-producing microbes to feed off the abundant deposits of organic carbon that had built up in the oceans at that time. This led to an explosive growth in these Methanosarcina microbes and an equally explosive release of their waste gases, which suffocated almost all other life-forms on land and in sea.

* Ordovician-Silurian (443m years ago): most of life lived in the seas. About 85 per cent of marine species were killed, mostly at two peak dying times separated by hundreds of thousands of years.

* Late Devonian (359m years ago): about three quarters of species went extinct over a period of several million years. Much of the sea became starved of oxygen, possibly due to asteroid impacts.

* Permian (252 million years ago): nicknamed the Great Dying because it was the biggest mass extinction in history, killing off about 96 per cent of marine species. Volcanoes were thought to be involved.

* Triassic-Jurassic (200m years ago): occurred over several million years at the end of the Triassic. About half of all species at the time disappeared, but strangely plants were not badly affected.

* Cretaceous-Tertiary (65m years ago): famous for being the death knell of the dinosaurs. A giant asteroid impact was almost certainly involved, possibly preceded by a long period of volcanic eruptions.
science  biology  life  explained 
april 2014 by aries1988
What Our Telescopes Couldn't See -
I left the world of professional astronomy some time ago. In the years since, I have often thought of how astronomy is seen as a benign, unbiased science. Its sole function is to increase our understanding of how the universe works: astronomers receive and record, but they do not experiment or perturb. They are not tainted by any application to, say, energy development or military technologies. Astronomy is, essentially, a passive science.

I remember realizing when I was a student that I could make a measurement of an object in the sky, and how extraordinary that felt to me, as if it were a way of reaching out and connecting with something so far away. But maybe I found distant galaxies easier to understand than the people around me, and I wonder if my work became a substitute for any true connection. I still look to the edge of the universe, but I try to remember always to keep one eye focused here on earth.
essay  astro  human  science  society  politics  telescope  astronomy  life  americas 
september 2013 by aries1988
The Notorious MSG's Unlikely Formula For Success
Without fermentation, we would live in a sad world without beer, cheese, miso, kimchi, and hundreds of other delicious things humans have enjoyed for centuries.

The flavor Chang and Felder are chasing in creating these new fermented products is umami — the savory fifth taste detectable by the human tongue along with salty, sweet, sour, and bitter. When bacteria and fungi break down the glucose in foods that are fermenting, they release waste products. And the waste valued in Momofuku’s lab above all others is glutamic acid, the amino acid that creates the taste of umami on our tongues.

Babies loved MSG just like adults, which is not a surprise. Human breast milk contains 19 milligrams of free glutamic acid per 100 grams — cow’s milk has 1 milligram. We’re programmed to crave umami from the womb.

The first slide contains a chart of the five known tastes discernible by the human tongue: Bitter is caused by acetic acid, salty is sodium chloride, and sweet is sucrose, not sugar. And there is monosodium glutamate, responsible for umami. This is a reminder — most certainly a calculated one — that almost everything we eat has a scientific name just as artificial-sounding as monosodium glutamate.
food  science  usa  history  asia  cuisine 
august 2013 by aries1988
googlereader  china  science  culture  comparison 
october 2012 by aries1988
科学松鼠会 » 概说阿尔茨海默症
science  china  medicine 
september 2012 by aries1988
googlereader  science  money  future  russia 
september 2012 by aries1988
PageRank Algorithm Reveals Soccer Teams' Strategies - Technology Review
这个文章好有创意,介绍使用PageRank算法研究球队战术——”PageRank Algorithm Reveals Soccer Teams' Strategies“: 。
data  analysis  discovery  google  science  sports 
august 2012 by aries1988
Securing the legacy of the world's greatest geek - opinion - 24 August 2012 - New Scientist
Matthew Inman wants to build a museum dedicated to inventor Nikola Tesla, the "greatest geek who ever lived"
googlereader  oatmeal  museum  future  project  science  scientist 
august 2012 by aries1988
To Know, But Not Understand
In 1963, Bernard K. Forscher of the Mayo Clinic complained in a now famous letter printed in the prestigious journal Science that scientists were generating too many facts. Titled Chaos in the Brickyard, the letter warned that the new generation of scientists was too busy churning out bricks — facts — without regard to how they go together. Brickmaking, Forscher feared, had become an end in itself. “And so it happened that the land became flooded with bricks. … It became difficult to find the proper bricks for a task because one had to hunt among so many. … It became difficult to complete a useful edifice because, as soon as the foundations were discernible, they were buried under an avalanche of random bricks.”
opinion  instapaper_favs  science  data 
august 2012 by aries1988
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