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3D printing: What is it, and how does it work?

Three-dimensional printers were all over the news this week, from a plastic printable gun to a live-saving medical device. Here’s a roundup of 3D printers and how they made headlines this week.

Photo Above: MakerBot Replicator 2X 3D desktop printer is on display at the MakeBot booth at the International Consumer Electronics Show in Las Vegas, Thursday, Jan. 10, 2013. (AP Photo/Jae C. Hong)

So what is it exactly?

Three-dimensional printing — and many insiders prefer the term “making” in order to differentiate from the traditional idea of printing — is at its most basic level the process of creating a digital 3D design, then slicing that design into layers and printing those layers one at a time until the final product takes shape.

Everything from the soles of running shoes to a new coffee cup can be made using this technique.

 

 

How does it work?

Three-dimensional printers typically use rolls of acrylic, ABS or metal as the raw material which is then fed into the machine.

Guided by computer-assisted design software (CAD), the printers melt down that raw material and repurpose it into solid objects by depositing droplets one layer at a time.

That material is then melded into shape using a precision laser, following the specifications set out in the CAD drawing.

As these layers — which can be microscopically thin — add up, the 3D object slowly takes shape.

When they were first invented 30 years ago, the original models of these machines were large, expensive and could only be operated by experts. But several companies are now producing hobbyist-sized versions that can be purchased for around $1,000 dollars and used at home by “makers.”

What are the advantages of 3D printing over traditional manufacturing?

Traditional manufacturing typically requires large blocks of material such as steel, which is then cut away using a CNC machine or a lathe to create the final product. As a result there is a much larger amount of waste than with 3D printing, which leaves behind almost no waste material whatsoever.

Other traditional forms of manufacturing, such as tool and die, require forms to be built which then hold the liquid raw material as it is poured in and allowed to cool — a process that typically requires large machinery, workshops and assembly-line support.

Three-dimensional printing, by contrast, can be done in anyone’s garage or basement, often with a microwave-sized device.

And unlike massive robotic assembly-line machinery, which needs to be retooled every time a new product is introduced, 3D printers can adjust to a new product-line just as fast as new software is introduced.

As a result, some experts have compared the advent of the 3D printer to the invention of the home computer or the online search engine — forecasting that it will change the world of manufacturing.

How can I get one?

Hobbyist-sized versions can be purchased directly from manufacturers such as Cubify and MakerBot, and Staples announced it will begin selling 3D printers on its website and eventually in stores.

Stratasys offers a range of printers from desktop models to commercial sized units designed for serious manufacturing.

How 3D printers are making headlines

This week, doctors saved a baby using a device made on a three-dimensional printer, NASA announced it is investing in 3D food-printing technology and a U.S. company was forced to remove plans for a working 3D printable handgun from its website.

In short, the technology that was virtually unheard of a couple of years ago — except among ultra-nerdy tech circles and in sci-fi book clubs — is now making headlines around the world on an almost daily basis.

Michigan doctors save baby using 3D-printed splint

The University of Michigan announced Wednesday that Dr. Glenn Green and Scott Hollister, who holds a Ph.D, had successfully designed and printed a tracheal splint for Kaiba, a 20-month-old baby boy. Kaiba had a rare condition known as severe tracheobronchomalacia, which caused him to stop breathing on a regular basis and require resuscitation daily.

The splint was printed from a biopolymer material called polycaprolactone, and was modeled directly from a CT scan of Kaiba’s trachea. The final product was sewn around the infant’s “airway to expand the bronchus and give it a skeleton to aid proper growth.”

“Over about three years, the splint will be reabsorbed by the body,” said a news release from the university.

NASA plans to print space food

NASA announced this week it is working with a Texas company to design, build and test a food printer that could work in space.

Essentially, Austin-based Systems and Materials Research Corp plans to create nutritionally rich food using powdered proteins, starches, fats and flavours with water or oil to create “digital” recipes that can be printed into pre-determined shapes.

Theoretically, a meal could be printed in the shape of chicken wings, or a roast beef dinner with all the trimmings. Astronauts could order up the meal they want, and the printer would create it on demand.

“The 3D printing system will provide hot and quick food in addition to personalized nutrition, flavor and taste,” the company wrote in its proposal to NASA.

“The biggest advantage of 3D printed food technology will be zero waste, which is essential in long-distance space missions.”

3D printable gun removed from Web

Earlier this month, a university student named Cody Smith successfully designed, printed – and fired – a plastic gun he created on a 3D printer. He named it “The Liberator.”

Then Smith posted plans for the weapon online, allowing anyone to download the specs and create their own firearm, provided they had access to the $8,000 Stratasys Dimension SST 3D printer.

His work inspired another “maker” to come up with plans for printable shotgun shells, which were then fired from Smith’s gun.

It was all too much for the U.S. State Department, which this week blocked Smith from distributing the plans.

“#DEFCAD has gone dark at the request of the Department of Defense Trade Controls,” stated a Tweet from Smith’s company. “Take it up with the Secretary of State.”

Still, the move came after the plans had already been downloaded more than 100,000 times, according to reports.

3D Printed Guns (Documentary)

Cody R Wilson has figured out how to print a semi-automatic rifle from the comfort of his own home. Now he’s putting all the information online so that others will join him. – This is a story about the rapid evolution of a technology that has forced the American legal system to play catch up. Cody Wilson, a 25 year old University of Texas Law student, is an advocate for the open source production of firearms using 3D printing technology. This makes him a highly controversial figure on both sides of the gun control issue. MOTHERBOARD sat down with Cody in Austin, Texas to talk about the constitution, the legal system, and to watch him make and test-fire a 3D-printed gun.

Check out our podcast with Cody here: http://bit.ly/VICE-Podcast-Cody-Wilson

Produced By Erin Lee Carr Edited by Chris O’Coin

Read more on MOTHERBOARD here: http://motherboard.vice.com/read/clic…

World’s first plastic gun made with 3D printer, successfully fired in the United States

The successful firing of the world’s first plastic gun made with 3D printing technology, has brought immediate calls for a ban on so-called “undetectable weapons.”

The gun, called “The Liberator”, was made and developed in Austin, Texas by a non-profit organization called Defense Distributed, which claims its purpose is to “produce and publish information related to the 3D printing of firearms.”

dezeen_First-3D-printed-gun-test-fired_3

Image Source: http://www.dezeen.com/2013/05/07/first-3d-printed-gun-fired/

The weapon was made with a 3D printer bought on eBay for just $8,000, and constructed by assembling 15 printed components made from ABS plastic. According to the BBC, which witnessed the weapon’s first test, only the 16th piece, the firing pin, is made from metal.

While Defense Distributed sees its guns as a way for people to defend themselves, at least one U.S. lawmaker wants the weapons to be made illegal.

Sen. Charles Schumer claims the plastic design would make the weapons undetectable by airport scanners.

“Guns are made out of plastic, so they would not be detectable by a metal detector at any airport or sporting event,” Schumer told reporters. “Only metal part of the gun is the little firing pin and that is too small to be detected by metal detectors, for instance, when you go through an airport.”

“A terrorist, someone who’s mentally ill, a spousal abuser, a felon can essentially open a gun factory in their garage,” Schumer added.

The weapon can fire a .380 handgun round, but Forbes, which was on hand for the firing, claimed a larger 5.7×28 rifle cartridge was tested, and blew apart The Liberator.

3D printing technology is seen as one future direction for manufacturing. Typically, it takes a digital representation of an object, and recreates it physically by laying down thin layers of material, usually plastics, until the digital file is literally printed in three dimensions.

The object could be an iPhone case, a simple tool, a high-capacity magazine, or if Defense Distributed has its way, all the parts for a single-use firearm. The notion behind 3D printing is that as sophisticated printers become more affordable, consumers can download designs at home for the goods they might otherwise purchase, and “manufacture” these goods themselves.

Forbes explained the technical process for creating the weapon on a 3D printer: “Fifteen of its 16 pieces have been created inside an $8,000 second-hand Stratasys Dimension SST 3D printer, a machine that lays down threads of melted polymer that add up to precisely-shaped solid objects just as easily as a traditional printer lays ink on a page.”

The 25-year-old head of Defense Distributed, Cody Wilson, a law student at the University of Texas who claims the project is “about liberty,” told the BBC that most people “weren’t expecting that this could be done.”

“There is a demand of guns — there just is. There are states all over the world that say you can’t own firearms — and that’s not true anymore.

“I’m seeing a world where technology says you can pretty much be able to have whatever you want. It’s not up to the political players any more.”

The gun is also the “first” 3D printed gun in just the most technical sense, as there are have been designs for single-use guns and gun components for years. However, the Liberator can be manufactured entirely in the 3D printer (with the exception of the small firing pin) and is reusable.

The RCMP says it has been monitoring the technology, and stressed there could be legal implications to using it.

“It is illegal to manufacture or possess a firearm without appropriate licences and applicable registrations,” warned RCMP spokesperson Julie Gagnon in a statement. “If law enforcement found an individual in possession of a 3D printer-manufactured firearm or parts of a firearm (e.g. magazines, barrels), without appropriate licences and registration, the firearm could be seized and the individual charged.”

Tony Bernardo, the acting director or the Canadian Shooting Sports Association, said the ability to produce printable firearms won’t be a problem for Canadians.

“It’s a total non-issue,” Bernardo said. “People have been making firearms by hand for 400 years. Many of the firearms that were used in World War I were produced in factories that didn’t even have electricity.”

Nonetheless, experts acknowledge the introduction of firearms and firearm components to 3D printing technology could make their acquisition easier.

The BBC asked Wilson if he felt any sense of responsibility about who might get access to a 3D gun, he agreed guns might be used to harm people.

“But I don’t think that’s a reason to not do it – or a reason not to put it out there,” he said.

No one from Defense Distributed was available for comment to Postmedia News, but its website makes clear the role it is playing in the highly charged U.S. gun debate.

“This project might change the way we think about gun control and consumption,” its website reads. “How do governments behave if they must one day operate on the assumption that any and every citizen has near instant access to a firearm through the Internet? Let’s find out.”

Errol Mendes, a professor of law at the University of Ottawa, says no specific law in Canada covers 3D guns.

“Because the technology is so new, I would be surprised if there was any law that regulated it,” Mendes said. But he added, “if there is an ability to actually 3D print prohibited weapons, then yes, one could be charged with importation of prohibited weapons.”

In Canada, anyone who does not already hold a licence for a prohibited firearm can be found guilty of an indictable offence if they are in possession of, or potentially if they print parts for, a prohibited firearm.

With files from Jesse M. Kelly, Postmedia News

Source (Read More): http://news.nationalpost.com/2013/05/06/worlds-first-plastic-gun-made-with-3d-printer-successfully-fired-in-the-united-states/

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Freeman Dyson and his gigantic sphere

Science is always creativity. This is a search for new solutions and a game of imagination. Without all this, dry logic is useless. However, sometimes fantasy is capable of leading even the most brilliant, the most rigorous mind into unknown, cosmic distances.

Freeman Dyson is the famous scientist who came up with a truly fantastic scientific concept. This concept is known more than the creator, although it bears his name. This is one of the largest designs ever proposed by man. This is Dyson’s sphere.

Golden Boy

Freeman Dyson at the age of ten

Freeman John Dyson was born on December 15, 1923 in the small English town of Crowthorne (Berkshire). He was the second child of the famous composer George Dyson, who was knighted in 1941, and social worker Mildred.

The respectable family lived well, not needing money. Young Freeman showed a talent for mathematics and computing at an early age, and at the age of eight he was sent to boarding school in Twyford. There Freeman spent most of his time, appearing at home only on vacation. In fact, the boy was left to himself, but in those days this was the norm.

Unlike many outstanding scientists, Dyson did not experience any difficulties with his studies – the love of reading instilled in his mother affected. But the boy did not really get along with his peers. According to Dyson, the school was dominated by athletes who loved to rub everyone’s face with sandpaper. Therefore, he preferred to spend time alone, sitting somewhere in a tree and reading novels by Jules Verne and Frank Baum. But over time, he nevertheless made friends – the same children who were fond of fantastic stories and dreamed of bringing them to life. At the same time, Dyson decided to connect life with science, which since then has always been associated with him with freedom and friendship.

Composer Sir George Dyson. According to Freeman, his father’s works still make more money than all the writings of the scientist.

At the age of twelve, Dyson was lucky: his father was invited to teach music at the prestigious Winchester College, where he took his son. Paternal position, however, did not bring concessions to Freeman – he had to pass a difficult exam, which he passed with brilliance.

At Winchester, Dyson continued to study mathematics. He spent many hours in the extensive library, reading in the original French and German mathematical works, as well as the texts of Professor Vinogradov on the theory of numbers.

Fifteen-year-old Dyson met World War II with almost enthusiasm. The reason for this was youthful maximalism. “Hearing the sounds of explosions, I felt: this is the collapse of the British Empire of evil,” he said. In 1943, Dyson, barely out of college, went to work in the Royal Air Force. His job was specific – he figured out the most efficient and safest position of the pilots in the cockpits. True, all his works were in vain: the military almost did not use the results of his research, out of habit relying on outdated experience.

After the end of the war, Freeman worked at home for another two years. However, he doubted that he would be able to realize himself in depressed post-war England. And in 1947 Dyson moved to the USA – the country of Oppenheimer, Schrodinger and Einstein. In addition to the desire to participate in something truly progressive and large-scale, he, according to his sister, had another motive – Dyson longed to gain independence, to get out of the shadow of his famous father. Such adventures rarely end with something good … But exceptions do happen.

Brilliant mind

Freeman Dyson and his gigantic sphere
Freeman Dyson and his gigantic sphere
Freeman Dyson and his gigantic sphere
Some well known published Dyson’s books

Dyson loved listening to the BBC’s coverage of life in the United States. And, surprising as it may seem, America really turned out to be as described: a country of extraordinary rise, including scientific.

Upon arrival, Freeman took a Ph.D. job at Cornell University. There he came under the patronage of Hans Bethe, one of the most famous physicists of the time. Bethe quickly realized that he had a non-trivial mind as his student. Soon Hans recommended that Freeman go to the annual summer school for physicists in Ann Arbor – a five-week celebration of science, where young scientists could listen to lectures by legendary physicists and even argue with them. There, Dyson met Richard Feynman, one of the creators of the American atomic bomb.

Cover and snippet of an unpublished fantasy story Dyson wrote as a child
Cover and snippet of an unpublished fantasy story Dyson wrote as a child

Feynman, who was only five years older than Dyson, was already a celebrity in the world of quantum electrodynamics. In 1948, he proposed the method of the so-called Feynman diagrams, which described the interaction of fermions (matter quanta) and bosons (field quanta) in space-time coordinates. The diagrams allowed the creation of a modern model of quantum physics. But one of the patriarchs of the then physics, Robert Oppenheimer, rejected the Feynman diagrams. But Dyson was confident in their correctness and in 1949 published a work in which he was able to mathematically substantiate Feynman’s calculations, which for the first time earned serious recognition.

In 1951, Dyson became professor of physics at Cornell. At the same time, the young scientist had not even received his doctorate at that time – an exceptional case. However, he taught there for only two years. In 1953, Robert Oppenheimer offered him a life appointment at the Institute for Advanced Study in Princeton – the place where Albert Einstein spent the last years of his life. Oppenheimer promised the young scientist complete freedom: he could pursue any field that interested him. 

Dyson accepted the offer – and taught there until 1994, and after that he remained an honorary professor. During this time, he managed to work on the theory of resonant paramagnetic absorption of radiation by metals and on the theories of magnetism and the energy distribution of nuclei. He has published numerous works on cosmology, philosophy and futurology, received many prizes – the Nobel Prize, however, still bypassed the great scientist. And, of course, he managed to get a family – he lives with his second wife Imme to this day, he has 6 children and already 16 grandchildren.

Heretic

In recent years, Dyson has been actively involved in the popularization of science. Several years ago, despite his considerable age, he traveled half the world with a series of lectures in which he expounded his thoughts on some of the problems facing humanity. He himself proudly calls his theses “heresies”, and himself – a heretic from science.

Friends note that Dyson has a rather modest, even shy character.

The first heresy is  about long-suffering global warming. Dyson is not the first to argue that the scale of the problem is vastly overblown, as is the role of humanity in the “impending disaster.” However, he makes a reservation: of course, the warming will not pass without a trace for humanity. But it is much more important to solve, for example, the problems of overpopulation and poverty. And warming comes and goes – and the role of man in it is insignificant.

The second heresy  is climate cycles. Dyson draws attention to the Sahara, which contains numerous artifacts from the past – and of sufficient quality. The Heretic recalls that 6,000 years ago the Sahara was humid – and in general the climate was completely different. In fact, the heresy lies in the fact that Dyson believes that the old, warmer and more humid climate is better than the current one.

To make the world hotter, Dyson calls for an increase in the concentration of carbon dioxide in the atmosphere – something that conservationists oppose. This would at least increase the size of potential agricultural land at the expense of the Sahara or Siberian tundra, which was a flourishing paradise.

The third heresy  is the rise of bioengineering. Dyson argues that people are full of stereotypes about genetic engineering, similar to long-standing stereotypes about computers – they say, it’s all expensive, cumbersome, incomprehensible and only needed by a handful of scientists. But this will not always be the case, and people should be ready for this. The industry is moving forward by leaps and bounds. Freeman even predicts the creation of bio games – they will be similar to modern video games, only with real seeds. While playing, the child will select and see the growth of the plant in real time. Ultimately, genetic engineering can lead to a change in a person as such … but this is the next heresy.

The fourth heresy  is about the essence of evolution and human biology. Dyson argues that humanity will soon return to the original evolutionary mechanisms of the “pre-Darwinian era.” Then there were no separate species and a kind of communism reigned at the cellular level – everyone exchanged data and did not differ from each other. But suddenly a certain cell stepped to a new level – and refused to share with others, forming the first species. So, according to the scientist, soon everything will change – humanity and all living things will again become one whole. And genetics and bioinformatics will help us with this.

Dyson draws an analogy with the computer industry. Like, once the industry was completely open until one company closed its sources. However, the very essence of software, according to the scientist, assumes open source. And something similar must happen with evolution.

The fifth heresy is  about nuclear weapons. Dyson is a well-known pacifist and proponent of general disarmament. The scientist insists that nuclear (as well as biological) weapons only increase tensions in the world, and do not lead to deterrence, as popular belief says.

Many have a condescending attitude at best to these “heresies”. Dyson is already over ninety, his last serious accomplishments were half a century ago – well, grandfather is out of his mind, let’s be tolerant. The accumulation of carbon dioxide will help us – well, he gave it out!

Фримен Дайсон и его исполинская сфера
Dyson’s son, George, is a renowned science historian. (Photo: Jacob Appelbaum / Flickr / CC BY-SA)

But Dyson did not come up with all these ideas by accident. This is definitely not the case when a person is trying to cling to fame and once again get into the news feed. Dyson wrote about the advent of biotechnology and nuclear weapons in the 1980s – for example, in the books “Infinite in all directions” and “Weapons and Hope”.

He himself admits that he cannot call himself an expert in all areas. “I am not suggesting that these heretical ideas are true,” says Dyson himself. “But pondering them is not at all harmful.” This, perhaps, is the secret of his longevity – both physical and mental: Freeman is interested in literally everything, he approaches any topic so responsibly, as if he is going to devote his whole life to it.

Physicist Marvin Goldberger said that for Dyson there seemed to be no problem that he could not solve. Marvin once worked on an incredibly convoluted integral equation. Dyson passed by and, of course, became interested in the problem. He honestly admitted that he had never seen anything like it, but he made a decision within twenty minutes. Later, this solution was derived by other scientists – and the equation bears their name. Freeman never chased fame or recognition – he just solved interesting problems.

“I still cannot imagine how you can think with such speed and such mathematical clarity. Against him, everyone else seemed inhibited. You can’t learn that. At least I just can’t do that, ”Goldberger said.

Orion Project

One of the famous but unrealized projects that Dyson was involved in was a spacecraft that would be propelled by nuclear explosions. In the United States, work on Orion began after the Soviet satellite was launched. The first Orions were planned to be launched already in 1968 – but in the end, as you know, NASA chose a less complex and dangerous version of chemical-powered rockets. Freeman’s son, science historian George Dyson, wrote a whole book about the history of the project.

Space colossus

All in all, the scientist Dyson is undoubtedly outstanding. But there are many outstanding scientists, but there are few scientists who have come up with a real Idea with a capital letter. And here we come to the idea for which Dyson became famous. This is definitely Dyson’s domain.

Dyson got the idea for this design in the fantastic book by Olaf Stapledon “The Creator of the Stars”. In it, the author describes a journey across the universe, many different races, societies and organizations. Among other things, Stapledon mentions a giant structure located around the star.

Dyson was inspired by this image and in 1960 proposed the idea of ​​such a sphere in his work “Search for artificial stellar sources of infrared radiation.” The scientist suggested that over time, the energy needs of any sufficiently developed civilization become so high that there is only one way to satisfy them. Namely, a colossal structure around the nearest star, which, with the help of batteries and photocells, could absorb and accumulate almost all the energy of the star.

Such a megastructure should become a noticeable source of infrared radiation that is fairly easy to detect. In the 1960s, there was much hope for the search for extraterrestrial life. The search for radio signals had already begun – Freeman proposed another method.

Dyson immediately said that his idea was hypothetical and in any case related to the distant future. He did not set the task of devising a way to build such a sphere. He, as always, was simply guided by the rule “thinking it over is not harmful at all.”

But many people immediately came up with a question: can humanity build such a sphere? And is it even possible to build it?

The radius of a hypothetical sphere around, for example, the Sun (far from the largest star) will be approximately equal to one astronomical unit (150 million kilometers). Not only the Sun would be inside the sphere, but also Mercury and Venus.

Of course, a lot of questions immediately arise. Where to get such a durable material? How long will it take to build?

And if you can answer the above with the vague “well, the technologies of the future, they will come up with something”, then other problems run into the laws of physics.

Freeman Dyson and his gigantic sphere

The main problem is gravity. Newton put an end to the idea of ​​a monolithic construction by proving the hollow sphere theorem. According to her, within a symmetric shell, the forces of gravity are mutually exclusive, so the body is in weightlessness.

As a result, the sphere will begin to drift and may simply “run over” the star, which will result in a complete disaster. Of course, the structure can be supported, say, with the help of motors – but imagine how much energy is required for constant maneuvers! Another problem is temperature. On the surface of a sphere, it can reach hundreds of degrees Celsius – too much for comfort. The earth is cooled by the atmosphere and rotation, the sphere will have neither one nor the other. There are two ways out: either spend a colossal amount of energy on cooling, or expand the radius of the structure.

Another challenge is the material. In 2012, the head of the board of directors of the American Institute of Ethics and New Technologies (IEET), George Dvorsky, said that humanity could well build a sphere in the next fifty years. He proposed to blow up Mercury, and the resulting material, in fact, and put on the construction site of the century.

Dvorsky’s theses were predictably criticized. There are a lot of questions – from “how, in fact, humanity will explode Mercury” to “how will you transfer the energy received from the Sun to the Earth.”

Freeman Dyson and his gigantic sphere

Ring with a diameter of 1 au – the simplest form of the Dyson structure

But the main thing is that the mass of Mercury is simply not enough to build a sphere with a radius of 1 astronomical unit. According to some estimates, there will not be enough material in the entire solar system to build a stable structure – the shell will literally be a few centimeters thick. Some crazy asteroid, and …

To solve these problems, Dyson introduced new concepts. He described several megastructures at once (the initial idea was called the “Dyson shell”), in which there is nothing openly impossible or contrary to the laws of physics.

The Roy, or Dyson Cluster,  is a system consisting of a huge number of independent satellites that tightly “stick around” the star, moving in orbit around it. The main difficulty lies in controlling the satellites – after all, you need to ensure that they do not collide, do not go out of orbit and keep a distance between themselves.

Freeman Dyson and his gigantic sphere

A Dyson bubble is  very similar to a swarm – with one difference: if the swarm is in continuous motion, then the bubble, on the contrary, is static. In the Bubble concept, the star is surrounded by many giant solar sails that remain in place due to the influence of the solar wind. The problem with movement control disappears, but another appears – the satellites should be extremely light and at the same time large.

Freeman Dyson and his gigantic sphere

Bubbleworld (literally – a bubble world)  is an unusual variation of a space colony, which is also built around a huge sphere filled with hydrogen (a gas giant is also suitable). Along its perimeter there is a vital shell heated by a ball – with soil, air and water.

Dyson’s network  is a huge array of cables and wires stretched from planet to star with photocells that absorb and transmit the energy of the luminary.

Be that as it may, many researchers around the world are still looking for the Dyson sphere – for example, within the SETI (Search for Extraterrestrial Intelligence) project, aimed at finding alien civilizations.

In 2015, astronomers recorded the strange behavior of the star KIC 8462852 – its luminosity over different periods of time (from 5 to 80 days) fell by up to 22%, as if something was blocking it. One of the hypotheses explained the phenomenon by the presence of an artificial structure around the star, like a Dyson swarm. However, there are other versions as well.

Dyson tree

Freeman Dyson and his gigantic sphere

The Dyson Tree is indeed a tree, but not quite ordinary. First, it must be created from scratch using bioengineering. Secondly, it will not grow in the forest at all. Such trees need to be planted on comets to create an atmosphere on them suitable for human life. Dyson believes that extraterrestrial life will first be discovered not on a planet or satellite, but on a comet or asteroid. And he even put $ 2,000 on it on longbets.org, a site created to make open-ended bets.

Mastermind

Undoubtedly the most famous piece to show Dyson’s influence is Larry Niven’s The Ringworld. Niven described a giant ring (millions of kilometers in radius) that revolves around a star to create gravity and is surrounded by a thousand-kilometer wall at the edges to contain the atmosphere. Over time, the idea of ​​a ring-world took on a separate life, even eclipsing its progenitor.

Freeman Dyson and his gigantic sphere
Dyson fence from “Futurama” designed to protect the solar system from illegal immigrants

Peter Hamilton’s Pandora’s Star begins with the discovery of objects similar to Dyson spheres. The sphere is mentioned in “The Rising of Endymion” by Dan Simmons, it is found in “Life Space” by Russian science fiction writer Andrey Livadny. The complete list includes several dozen pieces!

Perhaps the greatest science fiction writer who has dealt with this topic is Stanislav Lem. True, he did not introduce it into his books, but went through it with a roller of criticism. In the collection of essays “The Sum of Technology”, the Polish science fiction writer blows the sphere to smithereens, calling it “a curiosity rather than a concept.” His criticism is fair in everything but one. Lem writes: “Dyson is so convinced of the inevitability of the creation of” near-solar spheres “that he suggests starting a search for them in space …” But, as we know, Dyson was not convinced of anything – he only offered food for thought.

Freeman Dyson and his gigantic sphere
Dyson sphere up close. Shot from the series “Star Trek: The New Generation”

The Dyson sphere has taken root well in the gaming industry. You can stumble upon it in the Freelancer game. The main character of the game Prey is taken into the sphere. In Sid Meier’s classic strategy Alpha Centauri, building a sphere is considered one of the winning options. In the later stages, it can be built in the games of the Space Empires series. It is built by the geth from Mass Effect, and you can visit it in one of the storylines of the Russian strategy “Star Wolves: Civil War”. And in the wonderful game Euphloria (which was called Dyson in the early stages), you can grow a Dyson tree. In the cinema, Dyson was not lucky – neither the sphere nor his other concepts are practically found there. You can only recall the 1992 series of “Star Trek”. This, however, is understandable – a structure of this scale is too difficult to show realistically.

Frog in a jar

Dyson said: “There are bird scientists, and there are frog scientists. Birds soar high above the vast expanses of mathematics. Frogs swarm in the mud and see only flowers growing nearby. They enjoy looking at specific objects. “Freeman Dyson and his gigantic sphere

Dyson’s cake opened on the scientist’s 90th birthday (Photo: Andrea Kane, Dan Komoda)

In this classification, Dyson refers to himself as a frog. This could be explained by the inherent modesty of the scientist, but this is not entirely true. Dyson never really explored something in its entirety – he took only a separate, interesting aspect for him, jumping like a frog from one problem to another. And he did not care at all that the project as a whole was impracticable, he did not bother with technical characteristics – for him, a pure idea was always in the first place. His contribution to quantum mechanics, random matrices and astrophysics is enormous – but he seems to have never realized himself to the maximum, preferring to discover more and more new facets of our world.

He has not achieved fame among the masses. The name “Freeman” is more associated with another physicist – a lover of cascade resonances from the Half-Life series. Few know Dyson – he is far from Stephen Hawking or Neil DeGrasse Tyson, he is hardly mentioned in the media. If you score “Dyson” in the search, you will be greeted by an advertisement for vacuum cleaners.

Freeman Dyson and his gigantic sphere

Even at an advanced age, Freeman Dyson does not lose interest in the world around him.

His most famous “invention” – the sphere – he never considered a subject of pride, emphasizing that this was not his idea. For many other scientists, it would even be humiliating – to be known about you only by a near-fantastic concept, which was not even invented by you!

But Freeman Dyson’s ideas inspired and inspire many science fiction writers, artists, game developers. His concepts make people think about something great and distant. Impossible. So, everything is going as it should.

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Science & Technology

Dark secrets of DNA. Scientists talk about dangerous types of marriage

Scientists sequenced the genome of a man buried in a Stone Age tomb at Newgrange in Ireland and found that he was born as a result of incest. Marriages between close relatives were almost always prohibited due to the threat of degeneration. However, there is a risk of accidental incest. How dangerous it is from the point of view of genetics?

Power sealed in blood

For biological and cultural reasons, incest has been taboo since ancient times. They violated the ban in exceptional cases for the sake of strengthening power. Probably, the discovery of Irish scientists in Newgrange is connected with this – with the formation of the ruling elite in prehistoric society.

Dynastic marriages between relatives and cousins ​​were concluded in Ancient Egypt, the Inca empire, in the royal families of the Hawaiian archipelago. It once symbolized the purity of blood.
The majority of Iceland’s 360,000 inhabitants are descendants of several Viking groups who settled on the island in the 9th century.

The population is genetically very homogeneous. A few years ago, local company deCode Genetics even released an app based on a DNA test database to prevent young people from accidentally marrying a close relative.

DNA rushes to the rescue

Computer programs have been developed that compare a set of certain regions of the genome and determine the degree of relationship. Genealogical research is generally very popular now. People do DNA tests, upload the results to public databases such as Ancestry and Gedmach, and find relatives. First of all, those who do not know their origin: raised in orphanages, adopted.

Sometimes this kind of research brings unpleasant surprises. So, an American gave her husband a DNA test for his birthday. The results shocked the spouses: they turned out to be first-order cousins ​​on the father’s side. Moreover, the couple already had a two-year-old child. The woman spoke about this a year ago in the podcast of the American publication Slate.

Scientists immediately warned that sperm donation is fraught with accidental incest, and recommended strictly limiting the number of children conceived by one donor. In 2011, The New York Times reported 150 half-brothers and sisters. In 2017, the British press raised the issue of countries like Nigeria where the legislative regulation of this area is weak. Last year in the United States, there was a lot of discussion about the story of Dr. Kline, who tricked female clients of a reproductive clinic with his own sperm. Nearly five dozen of his biological children have found each other through public DNA testing databases.

How dangerous are “dynastic ties”

Children of incestuous marriages are twice as likely to get hereditary pathology. They have a higher risk of rare genetic diseases (orphan diseases) caused by recessive alleles – variants of genes whose activity is usually suppressed.

“Both spouses can inherit a recessive mutant allele from a common ancestor. They are healthy, but they have a heterozygous genotype, that is, with this allele. The probability that such a couple will have a sick child with a homozygous genotype is 25 percent,”.


If both parents carry an X chromosome with a mutant gene, then the risk of passing them on to both children increases to 25%. This situation often develops in closely related marriages.

In this case, medical genetic counseling is necessary in order to reduce the risk of passing on the genetic pathology to the child. Experts take into account everything: the degree of kinship, the state of health of family members, other kinship marriages in previous generations, ethnicity, since some hereditary diseases accumulate in certain ethnic groups.

“During pregnancy, you can undergo prenatal genetic diagnostics in order to obtain the most accurate data on the genetic material of the child,”.

Meanwhile, according to various estimates, about a billion people live in closed communities, where closely related marriages are not uncommon and even encouraged. For example, in Egypt, men could only marry if they had a home. Accordingly, the problem was solved by marriage between relatives living under the same roof – as a rule, cousins.

“In southern India, more than 52 percent of marriages are between cousins ​​and second cousins. Many nationalities have lived like this for thousands of years and have not disappeared from the face of the earth because of a rare recessive gene associated with any disease,”.

A person is able to adapt to almost any situation, Sosin believes. The most serious pathologies that are not compatible with life are eliminated even at the zygote stage – when the germ cells merge or the first few divisions of the embryo. If the pathology is not fatal, the child can be born.

Scientists give an example – Turkey, where marriages between cousins ​​and sisters are very common. Infant mortality is high there, and among the elderly it is common in countries with similar income and social security levels. This phenomenon is called the “Turkish puzzle”.

“In 1968, 27 percent of marriages in Turkey were concluded by close relatives. In 2008, 24. Studies have shown that, in general, first-degree marriages, that is, between a cousin and a sister, increase infant mortality by 45 percent. This is another insurance policy. , through which nature removes from the equation of life children who are not able to exist physically fully, “.

However, it is incorrect to deduce a certain average value of the risk of pathologies in closely related marriages. Each case is unique. It is especially difficult with multifactorial diseases, the causes of which remain unclear. By the way, they can be ecological, rooted in the way of life. For example, schizophrenia. Parents with this diagnosis have a 29 percent risk of transmitting the pathology to their child, and 41 percent if they are close relatives. According to some reports, children born in a marriage between a cousin and a sister have slightly worse IQ scores (by 0.8-1.3 points).

On the Internet, they write that in closely related marriages, almost half of the children are with hereditary pathologies. In fact, Sosin emphasizes, much less. According to various estimates, from one to nine percent, when it comes to parents who are each other’s first generation cousins.

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Science & Technology

The mystery of Azzo Bassou, nicknamed the planet’s last Neanderthal

For years, scientists have been looking for the missing link in human evolution, the “connection” between humans and their ape-like ancestors, according to evolutionary theory.

Scientists ran to look at new evidence of the existence of the Yeti and the Bigfoot, just to catch this very connection. But there was one person in the history of science who excited scientists’ minds for many years.

In 1931, a man named Azzo Bassou was discovered by the local press in Marrakech in Morocco.

Azzo Bassou lived in the Dades Valley, near the town of Skoura.

The locals knew about him. According to them, he lived in a cave, ate raw meat. He walked naked (they put him in a bag just to take pictures) and used very basic tools.

They also described him as a person with low intellectual abilities in a primitive way.

He had the ability to pronounce some words, but many of them were illegible.

His forehead was sunken, there was a convex jaw, a large nose and long arms that reached almost to the knees.

In 1956, the French writer Jean Boulet, accompanied by ethnologist Marcel Gomet, arrived in the city to find out and study this case.

Scientists who saw him compared his skull with the remains of Neanderthals found and were amazed at their similarity.

The tabloids immediately dubbed him “the missing link”, portraying him as the last living Neanderthal.

In the midst of his research, Azzo died at the age of 60. True, there were two of his alleged sisters with similar facial features – Hisa and Herkaya.

Both women did very hard physical work with ease and were as wild as their alleged relative.


After careful study, scientists concluded that most likely these three were sick with microcephaly.


Microcephaly is a significant decrease in the size of the skull and, accordingly, the brain with normal sizes of other parts of the body. Microcephaly is accompanied by mental impairment – from not pronounced imbecility to idiocy.

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