Tag: imagine (page 3 of 15)

Google’s AI Program Is Better At Video Games Than You





pcmag.com

IBM's Watson supercomputer may be saving lives and educating children, but Google's new AI program can master video games without human guidance.

The artificial intelligence system from London-based DeepMind, which Google acquired last year for a reported $400 million, represents a major step toward a future of smart machines.

Computers running the deep Q-network (DQN) algorithm were exposed to 49 retro games on the Atari 2600 and told to play them, without any direction from researchers. Using the same network architecture and tuning parameters, the machines were given only raw screen pixels, available actions, and game score as input.

For each level passed or high score earned, the computer was automatically rewarded with a digital treat.

"Strikingly, DQN was able to work straight 'out of the box' across all these games," DeepMind's Dharshan Kumaran and Demis Hassabis wrote in a blog post. The executives cited classic titles like Breakout, River Raid, Boxing, and Enduro.

The AI crushed even the most expert humans at 29 games, sometimes composing what the creators called "surprisingly far-sighted strategies" that allowed maximum scoring possibilities. It also outperformed previous machine-learning methods in 43 of 49 instances.

VIEW ALL PHOTOS IN GALLERY
Google DeepMind's findings were presented in a paper published in this week's Nature journal, which describes the key DQN features that allow it to learn.

"This work offers the first demonstration of a general purpose learning agent that can be trained end-to-end to handle a wide variety of challenging tasks," the researchers said. "This kind of technology should help us build more useful products."

Imagine asking the Google app to complete a complex task—like plan a backpacking trip through Europe, for example.

Google's DeepMind also hopes its technology will give researchers new ways to make sense of large-scale data, opening the door to discoveries in fields like climate science, physics, medicine, and genomics.

"And it may even help scientists better understand the process by which humans learn," Kumaran and Hassabis said, citing physicist Richard Feynman, who famously said, "What I cannot create, I do not understand."

For more, see How DeepMind Can Bring Google Artificial Intelligence to Life in the slideshow above.

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Let’s go back to the moon. No, Mars. No, the moon. The debate continues.




Excerpt from washingtonpost.com
By Christian Davenport 

To the moon again? Or Mars?
The questions have hung over NASA for years, and emerged again at a Senate committee hearing Tuesday.

Under President George W. Bush, the target was the moon. Under Obama, who said “we’ve been there before,” Mars became the mission.

But now as his term nears its end, there is some increasingly vocal criticism of that decision, saying there isn’t the funding or political will to get to Mars.

Focusing on Mars is a “flawed policy direction,” Scott Pace, the director of the Space Policy Institute at George Washington University testified on Tuesday. The shift in goals “blindsided” the international space community, he said. The moon “is the next logical target for all of our potential international partners.”

Russia has endorsed sending astronauts there, he said. China sent an unmanned rover to the moon, and unveiled designs for a new heavy rocket for deep space exploration. It even has plans to build its own space station. “Growing space powers such as the Republic of Korea and India have their own unmanned lunar ambitions,” Pace said, while adding that the private sector has also made huge advancements.

To regain its prominence in space, the United States should “lead a multinational program to explore the moon," Pace said.

If it doesn’t, he could imagine a “post-American space world, with a full range of manned and unmanned space activities, but without American leadership or even, in many cases, an American presence.”

Testifying before the same committee, Buzz Aldrin, the Apollo 11 pilot who was the second man to walk on the moon, said NASA is right to focus on going beyond the moon. "American leadership is more than simply getting one step ahead of our global competitors," he said. "American leadership is inspiring the world by consistently doing what no other nation is capable of doing."

Aldrin said he's working on a plan to get to Mars, and the next president should press ahead with the mission.

“I believe that early in the next administration, the nation must commit to developing a permanent presence on Mars,” he said.
With much fanfare, NASA has trumpeted its “Journey to Mars” campaign. And it has highlighted the unmanned test flight of the Orion capsule last year as evidence of its progress toward reaching the Red Planet. It is also developing a new heavy rocket, known as the Space Launch System, designed to go to Mars and deep space.

But critics have maintained that without the funding to support such an endeavor, the attempt is a little more than a public relations stunt. And while Sen. Ted Cruz (R-Texas) and other members the committee on Tuesday said they were committed to the new rocket, others have been less supportive.

“We made a wrong decision when we went down this road,” Rep. Dana Rohrabacher (R-Calif.) said at a hearing late last year.

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Earth’s Moon May Not Be Critical to Life Afterall




Excerpt from space.com

The moon has long been viewed as a crucial component in creating an environment suitable for the evolution of complex life on Earth, but a number of scientific results in recent years have shown that perhaps our planet doesn't need the moon as much as we have thought.

In 1993, French astronomer Jacques Laskar ran a series of calculations indicating that the gravity of the moon is vital to stabilizing the tilt of our planet. Earth's obliquity, as this tilt is technically known as, has huge repercussions for climate. Laskar argued that should Earth's obliquity wander over hundreds of thousands of years, it would cause environmental chaos by creating a climate too variable for complex life to develop in relative peace.
So his argument goes, we should feel remarkably lucky to have such a large moon on our doorstep, as no other terrestrial planet in our solar system has such a moon. Mars' two satellites, Phobos and Deimos, are tiny, captured asteroids that have little known effect on the Red Planet. Consequently, Mars' tilt wobbles chaotically over timescales of millions of years, with evidence for swings in its rotational axis at least as large as 45 degrees. 


The stroke of good fortune that led to Earth possessing an unlikely moon, specifically the collision 4.5 billion years ago between Earth and a Mars-sized proto-planet that produced the debris from which our Moon formed, has become one of the central tenets of the 'Rare Earth' hypothesis. Famously promoted by Peter Ward and Don Brownlee, it argues that planets where everything is just right for complex life are exceedingly rare.

New findings, however, are tearing up the old rule book. In 2011, a trio of scientists — Jack Lissauer of NASA Ames Research Center, Jason Barnes of the University of Idaho and John Chambers of the Carnegie Institution for Science — published results from new simulations describing what Earth's obliquity would be like without the moon. What they found was surprising.

"We were looking into how obliquity might vary for all sorts of planetary systems," says Lissauer. "To test our code we began with integrations following the obliquity of Mars and found similar results to other people. But when we did the obliquity of Earth we found the variations were much smaller than expected — nowhere near as extreme as previous calculations suggested they would be."
Lissauer's team found that without the moon, Earth's rotational axis would only wobble by 10 degrees more than its present day angle of 23.5 degrees. The reason for such vastly different results to those attained by Jacques Laskar is pure computing power. Today's computers are much faster and capable of more accurate modeling with far more data than computers of the 1990s.

Lissauer and his colleagues also found that if Earth were spinning fast, with one day lasting less than 10 hours, or rotating retrograde (i.e. backwards so that the sun rose in the West and set in the East), then Earth stabilized itself thanks to the gravitational resonances with other planets, most notably giant Jupiter. There would be no need for a large moon. 

Earth's rotation has not always been as leisurely as the current 24 hour spin-rate. Following the impact that formed the moon, Earth was spinning once every four or five hours, but it has since gradually slowed by the moon's presence. As for the length of Earth's day prior to the moon-forming impact, nobody really knows, but some models of the impact developed by Robin Canup of the Southwest Research Institute, in Boulder, Colorado, suggest that Earth could have been rotating fast, or even retrograde, prior to the collision.

Tilted Orbits
Planets with inclined orbits could find that their increased obliquity is beneficial to their long-term climate – as long as they do not have a large moon.


"Collisions in the epoch during which Earth was formed determined its initial rotation," says Lissauer. "For rocky planets, some of the models say most of them will be prograde, but others say comparable numbers of planets will be prograde and retrograde. Certainly, retrograde worlds are not expected to be rare."

The upshot of Lissauer's findings is that the presence of a moon is not the be all and end all as once thought, and a terrestrial planet can exist without a large moon and still retain its habitability. Indeed, it is possible to imagine some circumstances where having a large moon would actually be pretty bad for life.

Rory Barnes, of the University of Washington, has also tackled the problem of obliquity, but from a different perspective. Planets on the edge of habitable zones exist in a precarious position, far enough away from their star that, without a thick, insulating atmosphere, they freeze over, just like Mars. Barnes and his colleagues including John Armstrong of Weber State University, realized that torques from other nearby worlds could cause a planet's inclination to the ecliptic plane to vary. This in turn would result in a change of obliquity; the greater the inclination, the greater the obliquity to the Sun. Barnes and Armstrong saw that this could be a good thing for planets on the edges of habitable zones, allowing heat to be distributed evenly over geological timescales and preventing "Snowball Earth" scenarios. They called these worlds "tilt-a-worlds," but the presence of a large moon would counteract this beneficial obliquity change.

"I think one of the most important points from our tilt-a-world paper is that at the outer edge of the habitable zone, having a large moon is bad, there's no other way to look at it," says Barnes. "If you have a large moon that stabilizes the obliquity then you have a tendency to completely freeze over."

Barnes is impressed with the work of Lissauer's team.
"I think it is a well done study," he says. "It suggests that Earth does not need the moon to have a relatively stable climate. I don't think there would be any dire consequences to not having a moon."

Mars' Changing Tilt
The effects of changing obliquity on Mars’ climate. Mars’ current 25-degree tilt is seen at top left. At top right is a Mars that has a high obliquity, leading to ice gather at its equator while the poles point sunwards. At bottom is Mars with low obliquity, which sees its polar caps grow in size.


Of course, the moon does have a hand in other factors important to life besides planetary obliquity. Tidal pools may have been the point of origin of life on Earth. Although the moon produces the largest tides, the sun also influences tides, so the lack of a large moon is not necessarily a stumbling block. Some animals have also evolved a life cycle based on the cycle of the moon, but that's more happenstance than an essential component for life.

"Those are just minor things," says Lissauer.

Without the absolute need for a moon, astrobiologists seeking life and habitable worlds elsewhere face new opportunities. Maybe Earth, with its giant moon, is actually the oddball amongst habitable planets. Rory Barnes certainly doesn't think we need it.
"It will be a step forward to see the myth that a habitable planet needs a large moon dispelled," he says, to which Lissauer agrees.
Earth without its moon might therefore remain habitable, but we should still cherish its friendly presence. After all, would Beethoven have written the Moonlight Sonata without it?

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Every Black Hole Contains a New Universe


At the center of spiral galaxy M81 is a supermassive black hole about 70 million times more massive than our sun.



Excerpt from insidescience.org
A physicist presents a solution to present-day cosmic mysteries.



By: 
Nikodem Poplawski, Inside Science Minds Guest Columnist



(ISM) -- Our universe may exist inside a black hole. This may sound strange, but it could actually be the best explanation of how the universe began, and what we observe today. It's a theory that has been explored over the past few decades by a small group of physicists including myself. 
Successful as it is, there are notable unsolved questions with the standard big bang theory, which suggests that the universe began as a seemingly impossible "singularity," an infinitely small point containing an infinitely high concentration of matter, expanding in size to what we observe today. The theory of inflation, a super-fast expansion of space proposed in recent decades, fills in many important details, such as why slight lumps in the concentration of matter in the early universe coalesced into large celestial bodies such as galaxies and clusters of galaxies.
But these theories leave major questions unresolved. For example: What started the big bang? What caused inflation to end? What is the source of the mysterious dark energy that is apparently causing the universe to speed up its expansion?
The idea that our universe is entirely contained within a black hole provides answers to these problems and many more. It eliminates the notion of physically impossible singularities in our universe. And it draws upon two central theories in physics.
Nikodem Poplawski displays a "tornado in a tube." The top bottle symbolizes a black hole, the connected necks represent a wormhole and the lower bottle symbolizes the growing universe on the just-formed other side of the wormhole. Credit: Indiana University
In this picture, spins in particles interact with spacetime and endow it with a property called "torsion." To understand torsion, imagine spacetime not as a two-dimensional canvas, but as a flexible, one-dimensional rod. Bending the rod corresponds to curving spacetime, and twisting the rod corresponds to spacetime torsion. If a rod is thin, you can bend it, but it's hard to see if it's twisted or not.

The first is general relativity, the modern theory of gravity. It describes the universe at the largest scales. Any event in the universe occurs as a point in space and time, or spacetime. A massive object such as the Sun distorts or "curves" spacetime, like a bowling ball sitting on a canvas. The Sun's gravitational dent alters the motion of Earth and the other planets orbiting it. The sun's pull of the planets appears to us as the force of gravity.

The second is quantum mechanics, which describes the universe at the smallest scales, such as the level of the atom. However, quantum mechanics and general relativity are currently separate theories; physicists have been striving to combine the two successfully into a single theory of "quantum gravity" to adequately describe important phenomena, including the behavior of subatomic particles in black holes.
A 1960s adaptation of general relativity, called the Einstein-Cartan-Sciama-Kibble theory of gravity, takes into account effects from quantum mechanics. It not only provides a step towards quantum gravity but also leads to an alternative picture of the universe. This variation of general relativity incorporates an important quantum property known as spin. Particles such as atoms and electrons possess spin, or the internal angular momentum that is analogous to a skater spinning on ice.

Spacetime torsion would only be significant, let alone noticeable, in the early universe or in black holes. In these extreme environments, spacetime torsion would manifest itself as a repulsive force that counters the attractive gravitational force coming from spacetime curvature. As in the standard version of general relativity, very massive stars end up collapsing into black holes: regions of space from which nothing, not even light, can escape.
Here is how torsion would play out in the beginning moments of our universe. Initially, the gravitational attraction from curved space would overcome torsion's repulsive forces, serving to collapse matter into smaller regions of space. But eventually torsion would become very strong and prevent matter from compressing into a point of infinite density; matter would reach a state of extremely large but finite density. As energy can be converted into mass, the immensely high gravitational energy in this extremely dense state would cause an intense production of particles, greatly increasing the mass inside the black hole.
The increasing numbers of particles with spin would result in higher levels of spacetime torsion. The repulsive torsion would stop the collapse and would create a "big bounce" like a compressed beach ball that snaps outward. The rapid recoil after such a big bounce could be what has led to our expanding universe. The result of this recoil matches observations of the universe's shape, geometry, and distribution of mass.
In turn, the torsion mechanism suggests an astonishing scenario: every black hole would produce a new, baby universe inside. If that is true, then the first matter in our universe came from somewhere else. So our own universe could be the interior of a black hole existing in another universe. Just as we cannot see what is going on inside black holes in the cosmos, any observers in the parent universe could not see what is going on in ours.
The motion of matter through the black hole's boundary, called an "event horizon," would only happen in one direction, providing a direction of time that we perceive as moving forward. The arrow of time in our universe would therefore be inherited, through torsion, from the parent universe.
Torsion could also explain the observed imbalance between matter and antimatter in the universe. Because of torsion, matter would decay into familiar electrons and quarks, and antimatter would decay into "dark matter," a mysterious invisible form of matter that appears to account for a majority of matter in the universe.
Finally, torsion could be the source of "dark energy," a mysterious form of energy that permeates all of space and increases the rate of expansion of the universe. Geometry with torsion naturally produces a "cosmological constant," a sort of added-on outward force which is the simplest way to explain dark energy. Thus, the observed accelerating expansion of the universe may end up being the strongest evidence for torsion.
Torsion therefore provides a theoretical foundation for a scenario in which the interior of every black hole becomes a new universe. It also appears as a remedy to several major problems of current theory of gravity and cosmology. Physicists still need to combine the Einstein-Cartan-Sciama-Kibble theory fully with quantum mechanics into a quantum theory of gravity. While resolving some major questions, it raises new ones of its own. For example, what do we know about the parent universe and the black hole inside which our own universe resides? How many layers of parent universes would we have? How can we test that our universe lives in a black hole?
The last question can potentially be investigated: since all stars and thus black holes rotate, our universe would have inherited the parent black hole’s axis of rotation as a "preferred direction." There is some recently reported evidence from surveys of over 15,000 galaxies that in one hemisphere of the universe more spiral galaxies are "left-handed", or rotating clockwise, while in the other hemisphere more are "right-handed", or rotating counterclockwise. In any case, I believe that including torsion in geometry of spacetime is a right step towards a successful theory of cosmology.

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6 Supermaterials That Could Change Our World


Graphene

Excerpt from gizmodo.com

Graphene isn't the only game-changing material to come out of a lab. From aerogels nearly as light as air to metamaterials that manipulate light, here are six supermaterials that have the potential to transform the world of the future.

Self-healing Materials — Bioinspired Plastics

6 Supermaterials That Could Change Our World 
Self-healing plastic. Image credit: UIUC


The human body is very good at fixing itself. The built environment is not. Scott White at the University of Illinois at Urbana Champlain has been engineering bioinspired plastics that can self-heal. Last year, White's lab created a new polymer that oozes to repair a visible hole. The polymer is embedded with a vascular system of liquids that when broken and combined, clot just like blood. While other materials have been able to heal microscopic cracks, this new one repaired a hole 4 millimeter wide with cracks radiating all around it. Not big deal for a human skin, but a pretty big deal for plastic.

Engineers have also been envisioning concrete, asphalt, and metal that can heal themselves. (Imagine a city with no more potholes!) The rub, of course, lies in making them cheap enough to actually use, which is why the first applications for self-healing materials are most likely to be in space or in remote areas on Earth. 

Thermoelectric Materials — Heat Scavengers

6 Supermaterials That Could Change Our World 
Power blocks with thermoelectric material sued inside Alphabet Energy 's generator. Image credit: Alphabet Energy


If you've ever had a laptop burn up in your lap or touched the hot hood of car, then you've felt evidence of waste. Waste heat is the inevitable effect of running any that device that uses power. One estimate puts the amount of waste heat as two-thirds of all energy used. But what if there was a way to capture all that wasted energy? The answer to that "what if" is thermoelectric materials, which makes electricity from a temperature gradient.

Last year, California-based Alphabet Energy introduced a thermoelectric generator that plugs right into the exhaust pipe of ordinary generator, turning waste heat back into useful electricity. Alphabet Energy's generator uses a relatively cheap and naturally occurring thermoelectric material called tetrahedrite. Alphabet Energy says tetrahedrite can reach 5 to 10 percent efficiency.
Back in the lab, scientists have also been tinkering with another promising and possibly even more efficient thermoelectric material called skutterudite, which is a type of mineral that contains cobalt. Thermoelectric materials have already had niche applications—like on spacecraft—but skutterudite could get cheap and efficient enough to be wrapped around the exhaust pipes of cars or fridges or any other power-hogging machine you can think of. [Nature, MIT Technology Review, New Scientist]

Perovskites — Cheap Solar Cells

6 Supermaterials That Could Change Our World 
Solar cells made of perovskites. Image credit: University of Oxford


The biggest hurdle in moving toward renewable energy is, as these things always are, money. Solar power is getting ever cheaper, but making a plant's worth of solar cells from crystalline silicon is still an expensive, energy-intensive process. There's an alternative material that has the solar world buzzing though, and that's perovskites. 

Perovskites were first discovered over a century ago, but scientists are only just realizing its potential. In 2009, solar cells made from perovskites had a solar energy conversion efficiency of a measly 3.8 percent. In 2014, the number had leapt to 19.3 percent. That may not seem like much compared to traditional crystalline silicon cells with efficiencies hovering around 20 percent, but there's two other crucial points to consider: 1) perovskites have made such leaps and bounds in efficiency in just a few years that scientist think it can get even better and 2) perovskites are much, much cheaper. 

Perovskites are a class of materials defined by a particular crystalline structure. They can contain any number of elements, usually lead and tin for perovskites used in solar cells. These raw materials are cheap compared to crystalline silicon, and they can be sprayed onto glass rather than meticulously assembled in clean rooms. Oxford Photovoltaics is one of the leading companies trying to commercialize perovskites, which as wonderful as they have been in the lab, still do need to hold up in the real world. [WSJ, IEEE Spectrum, Chemical & Engineering News, Nature Materials]

Aerogels — Superlight and Strong

6 Supermaterials That Could Change Our World 
Image credit: NASA

Aerogels look like they should not be real. Although ghostly and ethereal, they can easily withstand the heat of a blowtorch and the weight of a car. The material is almost what exactly the name implies: gels where where the liquid has been replaced entirely by air. But you can see why it's also been called "frozen smoke" or "blue smoke." The actual matrix of an aerogel can be made of any number of substances, including silica, metal oxides, and, yes, also graphene. But the fact that aerogel is actually mostly made of air means that it's an excellent insulator (see: blowtorch). Its structure also makes it incredibly strong (see: car).

Aerogels do have one fatal flaw though: brittleness, especially when made from silica. But NASA scientists have been experimenting with flexible aerogels made of polymers to use insulators for spacecraft burning through the atmosphere. Mixing other compounds into even silica-based aerogels could make them more flexible. Add that to aerogel's lightness, strength, and insulating qualities, and that's one incredible material. [New Scientist, Gizmodo]

Metamaterials — Light Manipulators

If you've heard of metamaterials, you likely heard about it in a sentence that also mentioned "Harry Potter" and "invisibility cloak." And indeed, metamaterials, whose nanostructures are design to scatter light in specific ways, could possibly one day be used to render objects invisible—though it still probably wouldn't be as magical as Harry Potter's invisibility cloak. 

What's more interesting about metamaterials is that they don't just redirect visible light. Depending on how and what a particular metamaterial is made of, it can also scatter microwaves, radiowaves, or the little-known T-rays, which are between microwaves and infrared light on the electromagnetic spectrum. Any piece of electromagnetic spectrum could be manipulated by metamaterials. 

That could be, for example, new T-ray scanners in medicine or security or a compact radio antennae made of metamaterials whose properties change on the fly. Metamaterials are at the promising but frustrating cusp where the theoretical possibilities are endless, but commercialization is still a long, hard road. [Nature, Discover Magazine]

Stanene — 100 percent efficient conductor

6 Supermaterials That Could Change Our World 
The molecular structure of stanene. Image credit: SLAC


Like the much better known graphene, stanene is also made of a single layer of atoms. But instead of carbon, stanene is made of tin, and this makes all the difference in allowing stanene to possibly do what even wondermaterial extraordinaire graphene cannot: conduct electricity with 100 percent efficiency.

Stanene was first theorized in 2013 by Stanford professor Shoucheng Zhang, whose lab specializes in, along other things, predicting the electronic properties of materials like stanene. According to their models, stanene is a topological insulator, which means its edges are a conductor and its inside is an insulator. (Think of a chocolate-covered ice cream bar. Chocolate conductor, ice cream insulator.) 

This means stanene could conduct electricity with zero resistance even, crucially, at room temperature. Stanene's properties have yet to been tested experimentally—making a single-atom sheet tin is no easy task—but several of Zhang's predictions about other topological insulators have proven correct.

If the predictions about stanene bear out, it could revolutionize the microchips inside all your devices. Namely, the chips could get a lot more powerful. Silicon chips are limited by the heat created by electrons zipping around—work 'em too fast and they'll simply get too hot. Stanene, which conducts electricity 100 percent efficiency, would have no such problem. [SLAC, Physical Review Letters, Scientific American]

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Is Cancer a Gift and Not a Curse? Greg Giles

We all, thankfully, have to leave this world and return home eventually, one day, when it is time. This is an inevitable fact of our journey here. With this in mind, can you think of any other way to leave here that allows a soul to look back and refle...

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Why Bill Nye ‘The Science Guy’ Calls Evolution ‘Undeniable’ and Creationism ‘Inane’



Picture of thousands of galaxies
Gazing at galaxy clusters like Abell 2218, it's hard to imagine how we fit into the cosmos. Evolution can help with that, says Bill Nye.
Photograph by NASA, ESA, and Johan Richard (Caltech, USA)


Darwin's theory explains so much of the world, from bumblebees to human origins, says the Science Guy.


Excerpt from
By Jane J. Lee

With a jaunty bow tie and boyish enthusiasm, Bill Nye the Science Guy has spent decades decoding scientific topics, from germs to volcanoes, for television audiences. Last February, the former engineer defended the theory of evolution in a televised debate with young-Earth creationist Ken Ham, a vocal member of a group that believes the Earth is only 6,000 years old. Nye's decision to engage Ham kicked up plenty of criticism from scientists and creationists alike.

The experience prompted the celebrity science educator to write a "primer" on the theory of evolution called Undeniable: Evolution and the Science of Creation. In his new book, Nye delights in how this fundamental discovery helps to unlock the mysteries of everything from bumblebees to human origins to our place in the universe.

Who do you hope will read this book?
Grown-ups who have an interest in the world around them, people coming of age who have an interest in science, people who still want to know how the world works.

This is the big concern of mine with respect to the organization Answers in Genesis and Ken Ham and all those guys: their relentless, built-in attempts to indoctrinate a generation of science students on a worldview that is obviously wrong.

I worry about these kids—they're part of my society. We can't raise a generation of students who don't understand the fundamental idea in all of life science, any more than you want to raise a generation of kids who don't understand chemistry or physics or arithmetic.

How and when did you first encounter creationism?
About 20 years ago. I was a member of the Northwest Skeptics, which is the Seattle-based skeptics organization. We met people who insisted that the Earth was 6,000 years old. The inanity took my breath away. When you understand anything about astronomy or have just a rudimentary understanding of radioactivity, the Earth is patently not 6,000 years old. It's silly.

It's been said that a good way of convincing people of something is to appeal to their emotions. What do you think?
That's my business! In the book, I purposely spend a lot of time in the first person. The reason is, we find stories compelling. Stories are how we remember things, how we organize things.

By telling a story in the first person, it's hard to dismiss. If I say, "I remember the time I met Ivan the gorilla," it's really difficult for the listener or reader to go, "No, you don't!"

When you say, "I feel," it's really hard for the reader to say, "No, you don't." Yes, I do. I did a lot of that in the book...

Picture of a sweat bee pollinating a deadly nightshade flower
A fascination with bees and flight drew a young Bill Nye into the world of science and evolution.
Photograph by Mark W Moffett, National Geographic



Picture of the Earth seen from the International Space Station
One of the most fundamental ideas in explaining life on Earth is the theory of evolution, says Nye.
Photograph by NASA Earth Observatory

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Google Chairman Eric Schmidt: "The Internet Will Disappear"


 


Excerpt from hollywoodreporter.com

Google executive chairman Eric Schmidt on Thursday predicted the end of the Internet as we know it.

At the end of a panel at the World Economic Forum in Davos, Switzerland, where his comments were webcast, he was asked for his prediction on the future of the web. “I will answer very simply that the Internet will disappear,” Schmidt said.

“There will be so many IP addresses…so many devices, sensors, things that you are wearing, things that you are interacting with that you won’t even sense it,” he explained. “It will be part of your presence all the time. Imagine you walk into a room, and the room is dynamic. And with your permission and all of that, you are interacting with the things going on in the room.”

Concluded Schmidt: “A highly personalized, highly interactive and very, very interesting world emerges.”

The panel, entitled The Future of the Digital Economy, also featured Facebook COO Sheryl Sandberg and others.
Earlier in the debate, Schmidt discussed the issue of market dominance. The European Union has been looking at Google’s search market dominance in a long-running antitrust case, and the European parliament late last year even called for a breakup.
“You now see so many strong tech platforms coming, and you are seeing a reordering and a future reordering of dominance or leaders or whatever term you want to use because of the rise of the apps on the smartphone,” Schmidt said Thursday. “All bets are off at this point as to what the smartphone app infrastructure is going to look like” as a “whole new set” of players emerges to power smartphones, which are nothing but super-computers, the Google chairman argued. “I view that as a completely open market at this point.”

Asked about his recent trip to North Korea, Schmidt said the country has many Internet connections through data phones, but there is no roaming and web usage is “heavily supervised.” Schmidt said “it’s very much surveillance of use,” which he said was not good for the country and others.

Sandberg and Schmidt lauded the Internet as an important way to give more people in the world a voice. Currently, only 40 percent of people have Internet access, the Facebook COO said, adding that any growth in reach helps extend people’s voice and increase economic opportunity. “I’m a huge optimist,” she said about her outlook for the industry. “Imagine what we can do” once the world gets to 50 percent, 60 percent and more in terms of Internet penetration.
She cited women as being among the beneficiaries, saying the Internet narrows divides.

Schmidt similarly said that broadband can address governance issues, information needs, personal issues, women empowerment needs and education issues. “The Internet is the greatest empowerment of citizens … in many years,” he said. “Suddenly citizens have a voice, they can be heard.”
During another technology panel at the World Economic Forum on Thursday, Yahoo CEO Marissa Mayer, Liberty Global CEO Mike Fries and others answered questions on the need to regulate privacy standards on the Internet and for tech companies following the Snowden case, the Sony hack and the like.


Mayer said that the personalized Internet “is a better Internet,” emphasizing: “We don’t sell your personal data … We don’t transfer your personal data to third parties.” She said users own their data and need to have control, adding that people give up data to the government for tax assessment, social services and other purposes.
Fries said Liberty Global subscribers view billions of hours of content and generate billions of clicks, but added that “today we do nothing.” He explained: “We generate zero revenue from all of that information.” But he acknowledged that big data was big business for a lot of people.

Both executives said transparency was important to make sure users know privacy standards and the like.

Gunther Oettinger, a conservative German politician serving as the European Union’s commissioner for digital economy and society, said on the panel that “we need a convincing global understanding, we need a UN agency for data protection and security.” Asked what form that “understanding” should have, he said he was looking for “clear, pragmatic, market-based regulation.” Explained Oettinger: “It’s a public-private partnership.”

Fries said such a solution was likely not to happen in the near term, given the size of the EU. “I think it is going to take several years,” he said, adding that some countries’ parliaments would likely take a stab at it.

But he warned that a joint solution would make more sense. “We don’t want Germany to have its own Internet,” Fries said. “Some countries may build their own Internets” and “balkanize” the web, he warned.

Mayer said on the issue of regulation: “I like Tim’s idea better of the beneficent marketplace.” She spoke of fellow panelist and computer specialist Tim Berners-Lee, known as the inventor of the World Wide Web.

Asked how Yahoo stores and handles client records, she said the online giant “changed the way we store and communicate data” after Snowden and also changed encryptions between data centers. And the company protects users through encryption methods, she added. Mayer said that trust and confidence of Yahoo users has rebounded since.

Mayer was also asked what happens if a government asks for a user’s data, a question that has new significance after the recent terrorist attacks in Paris, which have led some to call for increased surveillance powers of the Internet for governments. Mayer said Yahoo always assesses if such a request is reasonable. “We have a very good track record for standing up to what’s not reasonable,” she said.

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Theoretical physics: The origins of space and time


Excerpt from nature.com
By Zeeya Merali


Many researchers believe that physics will not be complete until it can explain not just the behaviour of space and time, but where these entities come from.

“Imagine waking up one day and realizing that you actually live inside a computer game,” says Mark Van Raamsdonk, describing what sounds like a pitch for a science-fiction film. But for Van Raamsdonk, a physicist at the University of British Columbia in Vancouver, Canada, this scenario is a way to think about reality. If it is true, he says, “everything around us — the whole three-dimensional physical world — is an illusion born from information encoded elsewhere, on a two-dimensional chip”. That would make our Universe, with its three spatial dimensions, a kind of hologram, projected from a substrate that exists only in lower dimensions.

This 'holographic principle' is strange even by the usual standards of theoretical physics. But Van Raamsdonk is one of a small band of researchers who think that the usual ideas are not yet strange enough. If nothing else, they say, neither of the two great pillars of modern physics — general relativity, which describes gravity as a curvature of space and time, and quantum mechanics, which governs the atomic realm — gives any account for the existence of space and time. Neither does string theory, which describes elementary threads of energy.

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Zeeya Merali discusses some of the theories that are trying to explain the origins of space and time.


Van Raamsdonk and his colleagues are convinced that physics will not be complete until it can explain how space and time emerge from something more fundamental — a project that will require concepts at least as audacious as holography. They argue that such a radical reconceptualization of reality is the only way to explain what happens when the infinitely dense 'singularity' at the core of a black hole distorts the fabric of space-time beyond all recognition, or how researchers can unify atomic-level quantum theory and planet-level general relativity — a project that has resisted theorists' efforts for generations.

“All our experiences tell us we shouldn't have two dramatically different conceptions of reality — there must be one huge overarching theory,” says Abhay Ashtekar, a physicist at Pennsylvania State University in University Park.

Finding that one huge theory is a daunting challenge. Here, Nature explores some promising lines of attack — as well as some of the emerging ideas about how to test these concepts...

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Is AI a threat to humanity?

Excerpt from cnn.comImagine you're the kind of person who worries about a future when robots become smart enough to threaten the very existence of the human race. For years, you've been dismissed as a crackpot, consigned to the same category of peop...

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Google’s ‘goofy’ new self-driving car a sign of things to come

Google's latest prototype of its self-driving vehicle was unveiled Monday, Dec. 22, 2014. (Google photo) Excerpt from mercurynews.comMOUNTAIN VIEW -- Google unveiled its first "fully functional" prototype for its own self-driving car Monday and plans...

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Is a trip to the moon in the making?





Excerpt from bostonglobe.com

Decades after that first small step, space thinkers are finally getting serious about our nearest neighbor By Kevin Hartnett

This week, the European Space Agency made headlines with the first successful landing of a spacecraft on a comet, 317 million miles from Earth. It was an upbeat moment after two American crashes: the unmanned private rocket that exploded on its way to resupply the International Space Station, and the Virgin Galactic spaceplane that crashed in the Mojave Desert, killing a pilot and raising questions about whether individual businesses are up to the task of operating in space.  During this same period, there was one other piece of space news, one far less widely reported in the United States: On Nov. 1, China successfully returned a moon probe to Earth. That mission follows China’s landing of the Yutu moon rover late last year, and its announcement that it will conduct a sample-return mission to the moon in 2017.  With NASA and the Europeans focused on robot exploration of distant targets, a moon landing might not seem like a big deal: We’ve been there, and other countries are just catching up. But in recent years, interest in the moon has begun to percolate again, both in the United States and abroad—and it’s catalyzing a surprisingly diverse set of plans for how our nearby satellite will contribute to our space future.  China, India, and Japan have all completed lunar missions in the last decade, and have more in mind. Both China and Japan want to build unmanned bases in the early part of the next decade as a prelude to returning a human to the moon. In the United States, meanwhile, entrepreneurs are hatching plans for lunar commerce; one company even promises to ferry freight for paying customers to the moon as early as next year. Scientists are hatching more far-out ideas to mine hydrogen from the poles and build colonies deep in sky-lit lunar caves.  This rush of activity has been spurred in part by the Google Lunar X Prize, a $20 million award, expiring in 2015, for the first private team to land a working rover on the moon and prove it by sending back video. It is also driven by a certain understanding: If we really want to launch expeditions deeper into space, our first goal should be to travel safely to the moon—and maybe even figure out how to live there.
Entrepreneurial visions of opening the moon to commerce can seem fanciful, especially in light of the Virgin Galactic and Orbital Sciences crashes, which remind us how far we are from having a truly functional space economy. They also face an uncertain legal environment—in a sense, space belongs to everyone and to no one—whose boundaries will be tested as soon as missions start to succeed. Still, as these plans take shape, they’re a reminder that leaping blindly is sometimes a necessary step in opening any new frontier.
“All I can say is if lunar commerce is foolish,” said Columbia University astrophysicist Arlin Crotts in an e-mail, “there are a lot of industrious and dedicated fools out there!”

At its height, the Apollo program accounted for more than 4 percent of the federal budget. Today, with a mothballed shuttle and a downscaled space station, it can seem almost imaginary that humans actually walked on the moon and came back—and that we did it in the age of adding machines and rotary phones.

“In five years, we jumped into the middle of the 21st century,” says Roger Handberg, a political scientist who studies space policy at the University of Central Florida, speaking of the Apollo program. “No one thought that 40 years later we’d be in a situation where the International Space Station is the height of our ambition.”

An image of Earth and the moon created from photos by Mariner 10, launched in 1973.
NASA/JPL/Northwestern University
An image of Earth and the moon created from photos by Mariner 10, launched in 1973.
Without a clear goal and a geopolitical rivalry to drive it, the space program had to compete with a lot of other national priorities. The dramatic moon shot became an outlier in the longer, slower story of building scientific achievements.

Now, as those achievements accumulate, the moon is coming back into the picture. For a variety of reasons, it’s pretty much guaranteed to play a central role in any meaningful excursions we take into space. It’s the nearest planetary body to our own—238,900 miles away, which the Apollo voyages covered in three days. It has low gravity, which makes it relatively easy to get onto and off of the lunar surface, and it has no atmosphere, which allows telescopes a clearer view into deep space.
The moon itself also still holds some scientific mysteries. A 2007 report on the future of lunar exploration from the National Academies called the moon a place of “profound scientific value,” pointing out that it’s a unique place to study how planets formed, including ours. The surface of the moon is incredibly stable—no tectonic plates, no active volcanoes, no wind, no rain—which means that the loose rock, or regolith, on the moon’s surface looks the way the surface of the earth might have looked billions of years ago.

NASA still launches regular orbital missions to the moon, but its focus is on more distant points. (In a 2010 speech, President Obama brushed off the moon, saying, “We’ve been there before.”) For emerging space powers, though, the moon is still the trophy destination that it was for the United States and the Soviet Union in the 1960s. In 2008 an Indian probe relayed the best evidence yet that there’s water on the moon, locked in ice deep in craters at the lunar poles. China landed a rover on the surface of the moon in December 2013, though it soon malfunctioned. Despite that setback, China plans a sample-return mission in 2017, which would be the first since a Soviet capsule brought back 6 ounces of lunar soil in 1976.

The moon has also drawn the attention of space-minded entrepreneurs. One of the most obvious opportunities is to deliver scientific instruments for government agencies and universities. This is an attractive, ready clientele in theory, explains Paul Spudis, a scientist at the Lunar and Planetary Institute in Houston, though there’s a hitch: “The basic problem with that as a market,” he says, “is scientists never have money of their own.”

One company aspiring to the delivery role is Astrobotic, a startup of young Carnegie Mellon engineers based in Pittsburgh, which is currently positioning itself to be “FedEx to the moon,” says John Thornton, the company’s CEO. Astrobotic has signed a contract with SpaceX, the commercial space firm founded by Elon Musk, to use a Falcon 9 for an inaugural delivery trip in 2015, just in time to claim the Google Lunar X Prize. Thornton says most of the technology is in place for the mission, and that the biggest remaining hurdle is figuring out how to engineer a soft, automated moon landing.

Astrobotic is charging $1.2 million per kilogram—you can, in fact, place an order on its website—and Thornton says the company has five customers so far. They include the entities you might expect, like NASA, but also less obvious ones, like a company that wants to deliver human ashes for permanent internment and a Japanese soft drink manufacturer that wants to place its signature beverage, Pocari Sweat, on the moon as a publicity stunt. Astrobotic is joined in this small sci-fi economy by Moon Express out of Mountain View, Calif., another company competing for the Google Lunar X Prize.
Plans like these are the low-hanging fruit of the lunar economy, the easiest ideas to imagine and execute. Longer-scale thinkers are envisioning ways that the moon will play a larger role in human affairs—and that, says Crotts, is where “serious resource exploitation” comes in.
If this triggers fears of a mined-out moon, be reassured: “Apollo went there and found nothing we wanted. Had we found anything we really wanted, we would have gone back and there would have been a new gold rush,” says Roger Launius, the former chief historian of NASA and now a curator at the National Air and Space Museum.

There is one possible exception: helium-3, an isotope used in nuclear fusion research. It is rare on Earth but thought to be abundant on the surface of the moon, which could make the moon an important energy source if we ever figure out how to harness fusion energy. More immediately intriguing is the billion tons of water ice the scientific community increasingly believes is stored at the poles. If it’s there, that opens the possibility of sustained lunar settlement—the water could be consumed as a liquid, or split into oxygen for breathing and hydrogen for fuel.

The presence of water could also open a potentially ripe market providing services to the multibillion dollar geosynchronous satellite industry. “We lose billions of dollars a year of geosynchronous satellites because they drift out of orbit,” says Crotts. In a new book, “The New Moon: Water, Exploration, and Future Habitation,” he outlines plans for what he calls a “cislunar tug”: a space tugboat of sorts that would commute between the moon and orbiting satellites, resupplying them with propellant, derived from the hydrogen in water, and nudging them back into the correct orbital position.

In the long term, the truly irreplaceable value of the moon may lie elsewhere, as a staging area for expeditions deeper into space. The most expensive and dangerous part of space travel is lifting cargo out of and back into the Earth’s atmosphere, and some people imagine cutting out those steps by establishing a permanent base on the moon. In this scenario, we’d build lunar colonies deep in natural caves in order to escape the micrometeorites and toxic doses of solar radiation that bombard the moon, all the while preparing for trips to more distant points.
gical hurdles is long, and there’s also a legal one, at least where commerce is concerned. The moon falls under the purview of the Outer Space Treaty, which the United States signed in 1967, and which prohibits countries from claiming any territory on the moon—or anywhere else in space—as their own.
“It is totally unclear whether a private sector entity can extract resources from the moon and gain title or property rights to it,” says Joanne Gabrynowicz, an expert on space law and currently a visiting professor at Beijing Institute of Technology School of Law. She adds that a later document, the 1979 Moon Treaty, which the United States has not signed, anticipates mining on the moon, but leaves open the question of how property rights would be determined.

There are lots of reasons the moon may never realize its potential to mint the world’s first trillionaires, as some space enthusiasts have predicted. But to the most dedicated space entrepreneurs, the economic and legal arguments reflect short-sighted thinking. They point out that when European explorers set sail in the 15th and 16th centuries, they assumed they’d find a fortune in gold waiting for them on the other side of the Atlantic. The real prizes ended up being very different—and slow to materialize.
“When we settled the New World, we didn’t bring a whole lot back to Europe [at first],” Thornton says. “You have to create infrastructure to enable that kind of transfer of goods.” He believes that in the case of the moon, we’ll figure out how to do that eventually.
Roger Handberg is as clear-eyed as anyone about the reasons why the moon may never become more than an object of wonder, but he also understands why we can’t turn away from it completely. That challenge, in the end, may finally be what lures us back.

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Are we sending aliens the right messages?


(Nasa)


bbc.com

Artist Carrie Paterson has long dreamed of beaming messages far out to the emptiness of space. Except her messages would have an extra dimension – smell.

By broadcasting formulae of aromatic chemicals, she says, aliens could reconstruct all sorts of whiffs that help to define life on Earth: animal blood and faeces, sweet floral and citrus scents or benzene to show our global dependence on the car. This way intelligent life forms on distant planets who may not see or hear as we do, says Paterson, could explore us through smell, one of the most primitive and ubiquitous senses of all.
(Wikipedia)
It is nearly 40 years since the Arecibo facility sent messages out into space (Wikipedia)

Her idea is only the latest in a list of attempts to hail intelligent life outside of the Solar System. Forty years ago this month, the Arecibo radio telescope in Puerto Rico sent an iconic picture message into space – and we’ve arguably been broadcasting to aliens ever since we invented TV and radio.

However in recent years, astronomers, artists, linguists and anthropologists have been converging on the idea that creating comprehensible messages for aliens is much harder than it seems. This week, Paterson and others discussed the difficulties of talking to our cosmic neighbours at a conference called Communicating Across the Cosmos, held by Seti (Search for Extraterrestrial Intelligence). It seems our traditional ways of communicating through pictures and language may well be unintelligible – or worse, be catastrophically misconstrued. So how should we be talking to ET?

Lost in translation?

We have always wanted to send messages about humanity beyond the planet. According to Albert Harrison, a space psychologist and author of Starstruck: Cosmic Visions in Science, Religion and Folklore, the first serious designs for contacting alien life appeared two centuries ago, though they never got off the ground.


In the 1800s, mathematician Carl Gauss proposed cutting down lines of trees in a densely forested area and replanting the strips with wheat or rye, Harrison wrote in his book. “The contrasting colours would form a giant triangle and three squares known as a Pythagoras figure which could be seen from the Moon or even Mars.” Not long after, the astronomer Joseph von Littrow proposed creating huge water-filled channels topped with kerosene. “Igniting them at night showed geometric patterns such as triangles that Martians would interpret as a sign of intelligence, not nature.”

But in the 20th Century, we began to broadcast in earnest. The message sent by Arecibo hoped to make first contact on its 21,000 year journey to the edge of the Milky Way. The sketches it contained, made from just 1,679 digital bits, look cute to us today, very much of the ‘Pong’ video game generation.  Just before then, Nasa’s Pioneer 10 and 11 space probes each carried a metal calling card bolted onto their frame with symbols and drawings on the plaque, showing a naked man and woman.

Yet it’s possible that these kinds of message may turn out to be incomprehensible to aliens; they might find it as cryptic as we find Stone Age etchings.

Antique tech

“Linear drawings of a male and a female homo sapiens are legible to contemporary humans,” says Marek Kultys, a London-based science communications designer. ”But the interceptors of Pioneer 10 could well assume we are made of several separate body parts (i.e. faces, hair and the man’s chest drawn as a separate closed shapes) and our body surface is home for long worm-like beings (the single lines defining knees, abdomens or collarbones.).”

Man-made tech may also be an issue. The most basic requirement for understanding Voyager’s Golden Record, launched 35 years ago and now way out beyond Pluto, is a record player. Aliens able to play it at 16 and 2/3 revolutions a minute will hear audio greetings in 55 world languages, including a message of ‘Peace and Friendship’ from former United Nations Secretary General Kurt Waldheim. But how many Earthlings today have record players, let alone extraterrestrials?
(Nasa)
Our sights and sounds of Earth might be unintelligible to an alien audience (Nasa)



Time capsule

Inevitably such messages become outdated too, like time capsules. Consider the case of the Oglethorpe Atlanta Crypt of Civilization – a time capsule sealed on Earth in 1940, complete with a dry martini and a poster of Gone With the Wind. It was intended as a snapshot of 20th Century life for future humans, not aliens, but like an intergalactic message, may only give a limited picture to future generations. When, in 61,000 years, the Oglethorpe time capsule is opened, would Gone With The Wind have stood the test of time?


(Nasa)
This message was taken into the stars by Pioneer - but we have no idea if aliens would be able to understand it (Nasa)

Kultys argues that all these factors should be taken into account when we calculate the likelihood of communicating with intelligent life. The astronomer Frank Drake’s famous equation allows anyone to calculate how many alien species are, based on likely values of seven different factors. At a UK Royal Society meeting in 2010 Drake estimated there are roughly 10,000 detectable civilisations in the galaxy. Yet Kultys points out that we should also factor in how many aliens are using the same channel of communications as us, are as willing to contact us as we are them, whose language we hope to learn, and who are physically similar to us.

Another barrier we might consider is the long distance nature of trans-cosmos communication. It means that many years ‒ even a thousand ‒ could pass between sending a message and receiving a reply. Paterson sees romance in that. “Our hope for communication with another intelligent civilisation has a melancholic aspect to it. 
We are on an island in a vast, dark space. Imagine if communication… became like an exchange of perfumed love letters with the quiet agony of expectation... Will we meet? Will we be as the other imagined? Will the other be able to understand us?”

Ready for an answer?

Anthropologist John Traphagan of the University of Texas in Austin has been asking the same question, though his view is more cautious. "When it comes to ET, you'll get a signal of some kind; not much information and very long periods between ‘Hi, how are you?’ and whatever comes back. We may just shrug our shoulders and say 'This is boring’, and soon forget about it or, if the time lag wasn't too long, we might use the minimal information we get from our slow-speed conversation to invent what we think they're like and invent a kind concept of what they're after.”

(20th Century Fox)
The aliens in Independence Day (1996) did not come in peace (20th Century Fox)
While we have been sending out messages, we have not been preparing the planet for what happens when we get an interstellar return call. First contact could cause global panic. We might assume those answering are bent on galactic domination or, perhaps less likely, that they are peaceful when in fact they’re nasty.

Consider how easy it is to mess up human-to-human communications; I got Traphagan’s first name wrong when I e-mailed him for this article. An apology within minutes cleared up the confusion, yet if he had been an alien anthropologist on some distant planet it would have taken much longer to fix. He later confessed: "I could have thought this is a snooty English journalist and our conversation might never have happened."

Even if Earth’s interstellar messaging committees weeded out the typos, cultural gaffes are always a possibility. These can only be avoided by understanding the alien’s culture – something that’s not easy to do, especially when you’ve never met those you’re communicating with.

Rosy picture

So, what is the best way to communicate? This is still up for grabs – perhaps it’s via smell, or some other technique we haven’t discovered yet. Clearly, creating a message that is timeless, free of cultural bias and universally comprehensible would be no mean feat.


But for starters, being honest about who we are is important if we want to have an extra-terrestrial dialogue lasting centuries, says Douglas Vakoch, director of interstellar message composition at Seti. (Otherwise, intelligent civilisations who’ve decoded our radio and TV signals might smell a rat.)

(Nasa)
The golden discs aboard the Voyager spacecraft require aliens to understand how to play a record (Nasa)

“Let's not try to hide our shortcomings,” says Vakoch. “The message we should send to another world is straightforward: We are a young civilisation, in the throes of our technological adolescence. We're facing a lot of problems here on Earth, and we're not even sure that we'll be around as a species when their reply comes in. But in spite of all of these challenges, we humans also have hope – especially hope in ourselves."


Yet ultimately what matters, says Paterson, is that they stop and consider the beings who sent them a message; the people who wanted to say: “Here are some important things. Here’s our DNA, here is some maths and universal physics. And here is our longing and desire to say “I’m like you, but I’m different.”

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