This Week In Science

QUANTUM CHESHIRE CAT PHENOMENON OBSERVED FOR FIRST TIME

Quantum mechanics is so weird, people often resort to Alice in Wonderland metaphors to explain it. Particle physicists have now gone one better, actually creating particles modeled on Lewis Carroll’s Cheshire Cat.

The famous puss slowly disappeared leaving its grin behind, prompting Alice to say, "Well! I've often seen a cat without a grin, but a grin without a cat! It's the most curious thing I ever saw in my life!" In Nature Communications this week, a team led by Tobias Denkmayr, a PhD student at the Vienna University of Technology announced something even physicists might call "curiouser and curiouser"; success in separating properties from the particles that normally possess them.

In this case the particles were neutrons. The property was magnetic moment, the extent to which an object is susceptible to rotation by an external magnetic field. Although, as their name suggests, neutrons have no net electric charge, they do have a well established magnetic moments of - 0.97x10-26 JT-1, produced by an internal structure of one up and two down quarks. The negative sign is an indication of the neutrons align in the opposite direction to a magnetic field.

In the classical world we are familiar with the idea that a property like magnetic moment cannot be separated from its object – it would be like taking the taste away from a chocolate bar so that the bar produced no sensation on the tongue, but a disembodied taste could be detected somewhere quite distinct.

However, things work differently in the world of the very small. In the 1990s, Professor Yakir Aharonov of Tel Aviv University proposed the properties could indeed be detached from particles (his book explaining it is delightfully subtitled Quantum Theory for the Perplexed). The idea develops on Schredinger’s famous feline thought-experiment. However, instead of ending up with a live and dead cat, you have a cat without its properties, and properties without the cat. The naming after Carroll’s Cheshire moggy was inevitable.

The idea of Cheshire cat particles has become a topic for an increasing number of papers in the last few years, but these have generally been about theory – just as no one actually puts Felis catus in boxes with poison vial and radioactive sources, for all the papers discussing what would happen if you did.

Denkmayr and his co-authors, however, temporarily removed the magnetic moment from the neutrons using an interferometer. They used a silicon crystal to split a neutron beam and reported, “The experimental results suggest that the system behaves as if the neutrons go through one beam path, while their magnetic moment travels along the other.” The beams were then reunited, leaving no disembodied magnetic moments prowling the universe.

The absence of moment from the neutrons was established by testing their spin in a magnetic field using Aharonov's concept of "weak measurement" which allows observations to take place without disturbing the system as usually occurs in quantum circumstances.

The authors note, “The investigation of Schrödinger cats advanced the field of quantum information processing and communication.” They suggest the work could be useful in “a situation in which the magnetic moment of a particle overshadows another of the particle’s properties which one wants to measure very precisely. The Cheshire Cat effect might lead to a technology which allows one to separate the unwanted magnetic moment to a region where it causes no disturbance to the high-precision measurement of the other property.”

Read more at http://www.iflscience.com/physics/%E2%80%9Cquantum-cheshire-cat%E2%80%9D-phenomenon-observed-first-time#hgr01P4zi56FKKsb.99

INVENTOR DEVELOPS SYNTHETIC LEAF WHICH PRODUCES OXYGEN



Julian Melchiorri, a graduate of the Royal College of Art, claims to have developed a silk leaf that could create oxygen for space travel as well as make the air nicer here on Earth. The leaf was developed in conjunction with a silk lab from Tufts University

The leaf is created from a matrix of protein extracted from silk and chloroplasts, the organelle that allows plants and algae to perform photosynthesis. When provided with light and water, the synthetic leaf allegedly acts just like a real leaf and produces oxygen.

“It’s very light, low energy-consuming,” he explains. “It’s completely biological and my idea was to use the efficiency of nature in a man-made environment. I created some lighting out of this material, using the light to illuminate the house but at the same time to create oxygen for us.”

Malchiorri isn’t content to just think of a few small fixtures within the house as the only use for this product. His dreams for Silk Leaf are out of this world.

"NASA is researching different ways to produce oxygen for long-distance space journeys to let us live in space,” he continued. “This material could allow us to explore space much further than we can now."

In addition to meeting the breathing demands of astronauts and the first colonists of Mars and beyond, the material could be used on the facades of buildings and inside ventilation systems in order to generate fresh oxygen.

All of this does sound pretty great, but does not account for photosynthesis in its entirety. Let’s take a look at the equation:

6CO2 + 6H2O + --(Sunlight Energy)--> C6H12O6 + 6O2

The Silk Leaf accounts for the input of carbon dioxide, water, and light as well as the oxygen product, but what about all the sugar? Plants don’t perform photosynthesis purely as a public service; it is done so they can create food for themselves. There isn’t an explanation as to what happens to the carbon and hydrogen that the leaf takes in. Silk Leaf lacks the vacuoles, stems, and roots that store food in plants.

The video also claims that plants don’t grow in space, which isn’t true. There have been concerns in the past that roots require gravity in order to develop properly, but experiments from the ISS have shown that plants can grow in space. However, it would take a considerable amount of soil, water, and plants to generate enough oxygen for astronauts or a, so a lightweight alternative like Silk Leaf would be beneficial in that regard.



Read more at http://www.iflscience.com/technology/inventor-develops-synthetic-leaf-produces-oxygen#TgypDOj3fbYyIgB1.99

SCIENTISTS DEVELOP TECHNIQUE TO PRODUCE SELF-DEVELOPING ANTICANCER MOLECULES IN MINUTES

Scientists from the University of Warwick have developed a simple technique for the production of a variety of self-assembling molecules that could be used to treat both cancer and infection. The small molecules produced, called peptides, work by mimicking the architecture of components of the body’s natural defense system. While the molecules have only been tested in cancer cell lines so far, the results of these studies were promising as they demonstrated both toxicity and selectivity. The work has been published in Nature Chemistry.

Peptides are small molecules naturally found throughout the body that perform a wide range of biological functions. Like proteins, they’re chains of building blocks called amino acids strung together by a type of bond called a peptide bond, but proteins are larger than peptides.

Scientists are interested in these molecules as potential agents to treat infections or cancer, but so far producing them artificially has been costly, difficult to scale-up and also resulted in molecules that behave in an undesirable way. Furthermore, traditional peptides administered as drugs are rapidly neutralized by the body, rendering them useless.

The new technique, pioneered by Professor Peter Scott and colleagues, relies on chemical self-assembly and results in the rapid production of 3D helical molecules. “The chemistry involved is like throwing Lego blocks into a bag, giving them a shake, and finding that you have a model of the Death Star,” Scott said in a news-release. “The design to achieve that takes some thought and computing power, but once you’ve worked it out the method can be used to make a lot of complicated molecular objects.”

Complex self-assembly of big molecules happens all the time in nature, for example in the production of proteins. Developing a technique to trigger this process artificially in the lab without expensive equipment, however, has been a challenge, but the Warwick researchers may have cracked it.

Professor Scott explains that their novel process involves mixing two different organic chemicals, an amino alcohol derivative and a picoline, with iron chloride in a solvent, such as water or methanol. Within minutes, the molecules start to self-assemble, forming strong bonds and folding into a helix. The process is very efficient because the assembly instructions are encoded within the chemical ingredients, negating the need for costly equipment.

After removing the solvent, the scientists are left with peptides in the form of crystals that mimic the active regions of certain defense molecules found naturally in the body. The resulting molecules are helical, positively charged and both water- and fat-loving (amphiphilic).

The researchers have tested these peptides on a human colon cancer cell line and they were found to be highly toxic, but it will be a long time before they can be tested in human trials. That being said, the peptides were also found to be very selective, which is promising.

Read more at http://www.iflscience.com/health-and-medicine/scientists-develop-technique-produce-self-assembling-anticancer-molecules#14wq7oKRpXd2CIkY.99

NO, YOUR NOT ENTITLED TO YOUR OPINION

Every year, I try to do at least two things with my students at least once. First, I make a point of addressing them as “philosophers” – a bit cheesy, but hopefully it encourages active learning.

Secondly, I say something like this: “I’m sure you’ve heard the expression ‘everyone is entitled to their opinion.’ Perhaps you’ve even said it yourself, maybe to head off an argument or bring one to a close. Well, as soon as you walk into this room, it’s no longer true. You are not entitled to your opinion. You are only entitled to what you can argue for.”

A bit harsh? Perhaps, but philosophy teachers owe it to our students to teach them how to construct and defend an argument – and to recognize when a belief has become indefensible.

The problem with “I’m entitled to my opinion” is that, all too often, it’s used to shelter beliefs that should have been abandoned. It becomes shorthand for “I can say or think whatever I like” – and by extension, continuing to argue is somehow disrespectful. And this attitude feeds, I suggest, into the false equivalence between experts and non-experts that is an increasingly pernicious feature of our public discourse.
​The Conversation

Firstly, what’s an opinion?

Plato distinguished between opinion or common belief (doxa) and certain knowledge, and that’s still a workable distinction today: unlike “1+1=2” or “there are no square circles,” an opinion has a degree of subjectivity and uncertainty to it. But “opinion” ranges from tastes or preferences, through views about questions that concern most people such as prudence or politics, to views grounded in technical expertise, such as legal or scientific opinions.

You can’t really argue about the first kind of opinion. I’d be silly to insist that you’re wrong to think strawberry ice cream is better than chocolate. The problem is that sometimes we implicitly seem to take opinions of the second and even the third sort to be unarguable in the way questions of taste are. Perhaps that’s one reason (no doubt there are others) why enthusiastic amateurs think they’re entitled to disagree with climate scientists and immunologists and have their views “respected.”

Meryl Dorey is the leader of the Australian Vaccination Network, which despite the name is vehemently anti-vaccine. Ms. Dorey has no medical qualifications, but argues that if Bob Brown is allowed to comment on nuclear power despite not being a scientist, she should be allowed to comment on vaccines. But no-one assumes Dr. Brown is an authority on the physics of nuclear fission; his job is to comment on the policy responses to the science, not the science itself.

So what does it mean to be “entitled” to an opinion?

If “Everyone’s entitled to their opinion” just means no-one has the right to stop people thinking and saying whatever they want, then the statement is true, but fairly trivial. No one can stop you saying that vaccines cause autism, no matter how many times that claim has been disproven.

But if ‘entitled to an opinion’ means ‘entitled to have your views treated as serious candidates for the truth’ then it’s pretty clearly false. And this too is a distinction that tends to get blurred.

On Monday, the ABC’s Mediawatch program took WIN-TV Wollongong to task for running a story on a measles outbreak which included comment from – you guessed it – Meryl Dorey. In a response to a viewer complaint, WIN said that the story was “accurate, fair and balanced and presented the views of the medical practitioners and of the choice groups.” But this implies an equal right to be heard on a matter in which only one of the two parties has the relevant expertise. Again, if this was about policy responses to science, this would be reasonable. But the so-called “debate” here is about the science itself, and the “choice groups” simply don’t have a claim on air time if that’s where the disagreement is supposed to lie.

Mediawatch host Jonathan Holmes was considerably more blunt: “there’s evidence, and there’s bulldust,” and it’s no part of a reporter’s job to give bulldust equal time with serious expertise.

The response from anti-vaccination voices was predictable. On the Mediawatch site, Ms. Dorey accused the ABC of “openly calling for censorship of a scientific debate.” This response confuses not having your views taken seriously with not being allowed to hold or express those views at all – or to borrow a phrase from Andrew Brown, it “confuses losing an argument with losing the right to argue.” Again, two senses of “entitlement” to an opinion are being conflated here.

So next time you hear someone declare they’re entitled to their opinion, ask them why they think that. Chances are, if nothing else, you’ll end up having a more enjoyable conversation that way.

This article originally appeared in The Conversation and has been republished with

Read more at http://www.iflscience.com/brain/no-youre-not-entitled-your-opinion#HMvuMqhg1JCeFLA3.99

The black hole at the birth of the Universe

T he big bang poses a big question: if it was indeed the cataclysm that blasted our universe into existence 13.7 billion years ago, what sparked it?

Three Perimeter Institute researchers have a new idea about what might have come before the big bang. It's a bit perplexing, but it is grounded in sound mathematics and is it testable?

What we perceive as the big bang, they argue, could be the three-dimensional "mirage" of a collapsing star in a universe profoundly different than our own.

"Cosmology's greatest challenge is understanding the big bang itself," write Perimeter Institute Associate Faculty member Niayesh Afshordi, Affiliate Faculty member and University of Waterloo professor Robert Mann, and PhD student Razieh Pourhasan.

Conventional understanding holds that the big bang began with a singularity -- an unfathomably hot and dense phenomenon of spacetime where the standard laws of physics break down. Singularities are bizarre, and our understanding of them is limited.

"For all physicists know, dragons could have come flying out of the singularity," Afshordi says in an interview with Nature.

The problem, as the authors see it, is that the big bang hypothesis has our relatively comprehensible, uniform, and predictable universe arising from the physics-destroying insanity of a singularity. It seems unlikely.

So perhaps something else happened. Perhaps our universe was never singular in the first place.

Their suggestion: our known universe could be the three-dimensional "wrapping" around a four-dimensional black hole's event horizon. In this scenario, our universe burst into being when a star in a four-dimensional universe collapsed into a black hole.

In our three-dimensional universe, black holes have two-dimensional event horizons -- that is, they are surrounded by a two-dimensional boundary that marks the "point of no return." In the case of a four-dimensional universe, a black hole would have a three-dimensional event horizon.

In their proposed scenario, our universe was never inside the singularity; rather, it came into being outside an event horizon, protected from the singularity. It originated as -- and remains -- just one feature in the imploded wreck of a four-dimensional star.

The researchers emphasize that this idea, though it may sound "absurd," is grounded firmly in the best modern mathematics describing space and time. Specifically, they've used the tools of holography to "turn the big bang into a cosmic mirage." Along the way, their model appears to address long-standing cosmological puzzles and -- crucially -- produce testable predictions.

Of course, our intuition tends to recoil at the idea that everything and everyone we know emerged from the event horizon of a single four-dimensional black hole. We have no concept of what a four-dimensional universe might look like. We don't know how a four-dimensional "parent" universe itself came to be.
But our fallible human intuitions, the researchers argue, evolved in a three-dimensional world that may only reveal shadows of reality.

They draw a parallel to Plato's allegory of the cave, in which prisoners spend their lives seeing only the flickering shadows cast by a fire on a cavern wall.

"Their shackles have prevented them from perceiving the true world, a realm with one additional dimension," they write. "Plato's prisoners didn't understand the powers behind the sun, just as we don't understand the four-dimensional bulk universe. But at least they knew where to look for answers."

[hr]
Story Source:
The above story is based on materials provided by Perimeter Institute . Note: Materials may be edited for content and length.

[hr]
Journal Reference:

1. Razieh Pourhasan, Niayesh Afshordi, Robert B. Mann. Out of the White Hole: A Holographic Origin for the Big Bang. arXiv, 2014 [ link ]

IBM REVEALS INCREDIBLE BRAIN-INSPIRED CHIP

The world of computing just got a heck of a lot more exciting thanks to IBM’s incredibly powerful brain-inspired chip which was unveiled on Thursday. While their prototype single-core system, released back in 2011 as part of the Systems of Neuromorphic Adaptive Plastic Scalable Electronics (SyNAPSE) project, was impressive, this new chip blows the old one out of the water.

The human brain tops the computing chart as the most efficient organizational system in the world, so it’s no wonder IBM and collaborators chose to emulate its capabilities for their new system. This so-called “cognitive computing” aims to mimic the brain’s abilities for perception, action and cognition.

Traditional computing systems can be likened to the left brain; they’re analytical and mathematical with superb number-crunching abilities. But if we want something that could be used in more sophisticated systems, say artificial intelligence, then we’re going to need something more right brain-like as well, which is exactly what IBM have been working towards.

This new chip, which is the size of a postage-stamp, addresses the right brain functions of sensory processing and pattern recognition. The idea is to be able to process, respond to and “learn” from information gleaned from the environment. If successfully combined with a traditional “left brain” system, which is what IBM will be attempting over the coming years, we could have a “holistic computing intelligence” with vast capabilities in our hands.

The product, which has been coined “TrueNorth,” achieves this through a staggering network of 1 million programmable neurons, 256 million configurable synapses (connections) and over 4,000 neurosynaptic cores. To put this into perspective, the prototype had just 256 neurons, 260,000 synapses and one core. That’s a giant leap in just 3 years. According to wired.com, these neurons, or “spiking neurons,” essentially allow the chip to encode data as patterns of pulses, which is much like one of the many ways scientists believe the brain stores information. Details of the chip can be found in Science.

IBM has put the abilities of this chip to the test in various artificial intelligence tasks, such as image recognition. One test, for example, involved presenting the chip with a variety of images, and it was found to be able to recognize a variety of objects with around 80% accuracy. Remarkably, the system was able to do all of this on just 63 mW of power.

Like the 2011 version, this chip is just a prototype. IBM hopes to eventually produce a neuro-synaptic chip system with a whopping 10 billion neurons and 100 trillion synapses that can process information whilst consuming just 1 kW of power. Eventually, multiple chips will be strung together on a chip board to create a huge network.

IBM envisages that the technology could have a variety of applications, such as vision assistance for the blind, health monitoring and transportation such as self-driving cars.

[Via AFP, Wired and IBM]

Read more at http://www.iflscience.com/technology/ibm-reveals-incredible-new-brain-inspired-chip#7Cu2vACXZ7AREUjG.99

http://www.youtube.com/watch?v=Salz7uGp72c

Since 2000, the International Space Station has been a home away from home to over 200 astronauts and extremely fortunate tourists from all over the world. No other spacecraft has been continually occupied by humans longer than the ISS. It serves as a laboratory to perform experiments that would be impossible to do under the pull of gravity from Earth’s surface, placing an incredible amount of importance on those selected to go into space. It also has a hell of a view.

Time-Lapse Footage From ISS Gives Spectacular Aerial View of Earth at Night

In order to to keep its orbit at a relatively low altitude, the ISS maintains a speed of about 27,600 km/h (17,150 mph). This allows the crew to completely orbit the Earth in just over 90 minutes, completing over 15 every day. This gives them the ability to see our planet from a very unique perspective. In an hour and a half, the astronauts can observe every desert, every ocean, and every mountain. But what does it look like in the dark?

At night, the light from below can be seen very clearly. Large cities, huge storms, and aurorae illuminate the surface of the planet. Words can’t even do the view justice, so check out this amazing time-lapse video and see for yourself:

Read more at http://www.iflscience.com/space/time-lapse-footage-iss-gives-spectacular-aerial-view-earth-night#QSOAuXHh3iP1I2PM.99

http://www.youtube.com/watch?v=FG0fTKAqZ5g#t=31

Student Develops Inexpensive Solar Lens To Purify Polluted Water

Deshawn Henry, a Civil Engineering sophomore at the University of Buffalo, spent his summer developing a solar lens using inexpensive supplies from a hardware store that can clean 99.9% of pathogens in a liter of water in about an hour. The research project is practical and inexpensive, with the potential to be widely implemented and save lives.

Over one billion people around the world lack consistent access to clean water, leading to the death of a child under the age of 5 every single minute. Many water treatment options are expensive.

The device itself has a rather humble appearance, with a six-foot-tall frame of 2x4s topped with a lens constructed of plastic sheeting and water, which focuses down onto a treatment container for the water. This simplicity of design and the inexpensive nature of the building materials means that many living in impoverished areas would be able to obtain the technology and provide clean water for their families.

The lens is able to magnify sunlight and heat a liter of water to about 130-150 degrees Fahrenheit in about an hour. As the sun changes position in the sky, the treatment container for the water needs to be adjusted in order to stay under the focal point of the lens. This heating process eliminates about 99.9% of pathogens found in the water, leaving it clean and drinkable.

“The water lens could have a huge impact in developing countries,” Henry said in a press release. “Millions of people die every year from diseases and pathogens found in unclean water, and they can’t help it because that’s all they have. Either they drink it or they die.”

The design of the lens came with a bit of trial and error. While more water would be able to magnify more sunlight, the thicker plastic needed to hold the heavier amount of water was more opaque, which diminished the effect. Thus, it was important to strike a balance and find what would be most practical in the system. However, the issue of water loss is one that has not been made entirely clear. A lid could potentially diminish the efficiency of the lens, but leaving it off could result in more water evaporating than can be used to effectively clean the water.

All in all, not bad for a summer project.

“I have seen how intense research activities can inspire UB students and educate the next generation of innovators,” added James Jensen, the professor who supervised Henry’s project over the summer. “Deshawn’s work would allow a family in sunny regions to treat drinking water without having to expend energy or rely on imported technologies.”

Though the summer semester is over, Henry is not giving up on his project. Currently, his design that cleans a liter per hour is only enough to meet about one third of the demand for a family of five. He hopes to continue working and develop a larger lens that would be able to clean the amount of water needed.

Read more at http://www.iflscience.com/technology/student-develops-inexpensive-solar-lens-purify-polluted-water#OmumcXf1wBE2QHlF.99

Creating plasma using a grape and a microwave is one of the great home science experiments. In this video Veritasium shows you how and discusses the science.

For the confused, the plasma made here is the fourth state of matter, after solids, liquids and gas. It shouldn’t be confused with blood plasma, which is actually a liquid and something you probably shouldn't be experimenting with at home.

That leaves the question, why grapes? As Derek and Steve note, lots of things will work, and you can have plenty of fun finding out which ones do. However, a typical large grape is about a quarter the wavelength of the microwaves your oven produces, which is the perfect size to act as an antenna. The grape needs to be cut so that the joining section heats up to the point where it vaporizes while the rest of the grape is still intact.

http://www.youtube.com/watch?v=RwTjsRt0Fzo&list=UUHnyfMqiRRG1u-2MsSQLbXA



Read more at http://www.iflscience.com/physics/how-make-plasma-using-grape-and-microwave#xkuCJJWBJMVQozAA.99