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Not everything in science has to be serious and so – meet Tom Dickson. Tom runs a very successful YouTube channel called ‘Will it Blend’. Every week he puts something different in his industrial strength blender. This week it’s neodymium magnets. – Deskarati
Well, this is disappointing. A team of astronomers announced last year that they thought they had strong and direct evidence for cosmic inflation in the extremely early Universe. But, after follow-up analysis, it turns out the evidence is far weaker, and it appears inconclusive one way or the other. Bummer.
OK, so what’s the scoop? First, here’s the announcement from last year when it was thought that the evidence was really good. The details are there.
But here’s a summary: Right after the Universe formed, it’s thought that it underwent an extremely short (to us) period of rapid growth, way faster than the usual cosmic expansion we see today. This event is called “inflation”, and it explains a variety of conditions in the Universe today that would be pretty hard to understand without it.
The problem is, the evidence for inflation is indirect; circumstantial. It explains stuff we already see pretty well, but it also makes predictions about the Universe, too, but we haven’t seen that evidence yet. For example, inflation would have created ripples in the fabric of spacetime, called gravitational waves. These ripples would affect matter in the Universe, and that would in turn affect the light we see coming from the early Universe. Read the rest of Phil’s article here Cosmic inflation: Evidence still not in..
Saab’s Soft Armour system offers protection against ballistic penetration up to NATO 7.62 mm AP ammunition (STANAG level III). The system is a box concept filled with hard ceramic balls. The system is especially designed to enhance survivability and can be fitted to any structure prior to missions, or even retrofitted to existing structures in operational theatre.
A unique ceramic material protects against ballistic penetration. Soft Armour is a patented ballistic protection technology that provides security for people in vulnerable environments. Soft Armour also protects critical equipment and facilities. Soft Armour protects against all small arms ammunition including armour piercing. The system has a lower total cost than ceramic and composite protection, with reusability, multi-hit capabilities and high flexibility.
Before he went down in history as one of the greatest film directors of all time, 17-year-old Stanley Kubrick was known for something else – New York City subway photography. Over two weeks in 1946, Kubrick worked for LOOK magazine to capture the everyday lives and intimate moments of the people of a bygone era.
While working for LOOK, Kubrick completed 129 assignments for a total of 15,000 photos. His photos captured the mundane and everyday side of an era often heavily romanticized in the U.S., giving us a closer and more identifiable look at their lives. They commuted just like us! Via boredpanda
The quintessential feature of a black hole is its “point of no return,” or what is more technically called its event horizon. When anything—a star, a particle, or wayward human—crosses this horizon, the black hole’s massive gravity pulls it in with such force that it is impossible to escape. At least, this is what happens in traditional black hole models based on general relativity. In general, the existence of the event horizon is responsible for most of the strange phenomena associated with black holes.
In a new paper, physicists Ahmed Farag Ali, Mir Faizal, and Barun Majunder have shown that, according to a new generalization of Einstein’s theory of gravity called “gravity’s rainbow,” it is not possible to define the position of the event horizon with arbitrary precision. If the event horizon can’t be defined, then the black hole itself effectively does not exist.
“In gravity’s rainbow, space does not exist below a certain minimum length, and time does not exist below a certain minimum time interval,” Ali, a physicist at the Zewail City of Science and Technology and Benha University, both in Egypt, told Phys.org. “So, all objects existing in space and occurring at a time do not exist below that length and time interval [which are associated with the Planck scale]. As the event horizon is a place in space which exists at a point in time, it also does not exist below that scale.”
When Ali talks about “all objects,” he literally means everything around us, including ourselves.
“We also do not exist physically below that length and time interval,” he said. “However, for us, our house, our car, etc., it does not matter if we do not exist at any one point of space and time, as long as we exist beyond a certain interval. However, for the event horizon it does matter, and this causes the main difference in our calculations.” Via Black holes do not exist where space and time do not exist, says new theory.
Scientists from Stanford Medical Center have devised a technique for extending the length of human telomeres. It’s a breakthrough that could eventually result in therapies to treat a host of age-related diseases, including heart disease and diabetes. It could also result in longer, healthier lives.
Telomeres are those critical protective caps located on the tips of chromosomes. Think of them as those protective pieces of plastic on the ends of your shoelaces. Without them, the tips basically fall apart, which is kind of what happens with chromosomes over time; human telomeres, which are about 8,000 to 10,000 nucleotides long, get shorter and shorter with each cell division. Over time, they reach a critical length, and the cell stops dividing, or simply dies. At the macroscale, we experience this as senescence, or aging, as your body’s cells progressively lose the ability to replenish.
So you can see why this breakthrough, in which the Stanford scientists rapidly and efficiently increased the length of human telomeres, is big news. Via New Technique Reverses Aging By Decades In Cultured Human Cells.
Move over, covalent and ionic bonds, there’s a new chemical bond in town, and it loves to shake things up. It’s taken decades to nail down, but researchers in Canada have finally identified a new chemical bond, which they’re calling a ‘vibrational bond’.
This vibrational bond seems to break the law of chemistry that states if you increase the temperature, the rate of reaction will speed up. Back in 1989, a team from the University of British Columbia investigated the reactions of various elements to muonium (Mu) – a strange, hydrogen isotope made up of an antimuon and an electron. They tried chlorine and fluorine with muonium, and as they increased the heat, the reaction time sped up, but when they tried bromine (br), a brownish-red toxic and corrosive liquid, the reaction time sped up as the temperature decreased. The researchers, Amy Nordrum writes for Scientific American, “were flummoxed”.
Perhaps, thought one of the team, chemist Donald Flemming, when the bromine and muonium made contact, they formed a transitional structure made up of a lightweight atom flanked by two heavier atoms. And the structure was joined not by van der Waal’s forces – as would usually be expected – but by some kind of temporary ‘vibrational’ bond that had been proposed several years earlier. Continue reading
For the first time in almost 100 years, a critically endangered Sierra Nevada red fox (Vulpes vulpes necator) has been spotted in California’s Yosemite National Park.
Motion-sensing cameras at the north of the park captured two photographs of the animal, once in December 2014 (above) and again earlier this month, allowing researchers to identify and confirm the sighting.
It’s estimated that there are only 50 of the Sierra Nevada red foxes left, although they once were common across the Sierra Nevada mountain range, as well as other ranges across California. Via ScienceAlert.
In Ancient Greece, victorious athletes were presented with laurel wreaths to wear. They were, and still are, signs of great accomplishment, unless you start resting on them
To ‘rest on your laurels’ means that you get lazy or complacent about what you could achieve because you’re too busy basking in the memories of former glories. It’s a phrase that continues to have significant relevance in the world of sport (‘Yeah, you may have won the World Cup but don’t rest on your laurels!’), which is also where it originated.
Winning competitors in the Ancient Greek Phythian Games, a forerunner of the Olympics founded roughly in the 6th century BC, were given wreaths made of the aromatic laurel leaves as a symbol of their triumph. It was believed that the god Apollo declared the laurel plant sacred after his true love – the nymph Daphne – was turned into one. That is why Apollo was depicted wearing a crown of laurel. As the Phythian Games honoured Apollo, a laurel wreath was the appropriate prize for a victor, or ‘laureate’.
The Romans borrowed the idea and began presenting laurel wreaths to victorious military commanders. But there was no implication that ‘resting’ on them was bad. Roman generals could spend the rest of their careers savouring their past successes. The negative connotation, and the saying, only came about millennia after the decline of the Ancient Greek and Roman empires.
A ‘laureate’ is still an esteemed title today, with recipients of the Nobel Prize being referred to as Nobel Laureates. Via Why we say: ‘resting on your laurels’
Every wonder what it would look like if you exploded an orange and filmed the carnage at 62,000 frames per second? Turns out, it looks a lot like the end of a very small world. Via Technology.
Modern Europeans have inherited about 4 percent of their genes from Neanderthals, meaning the two groups mated at some point in the past. But the question is, where and when?Characteristics of a partial skull recently discovered in Manot Cave in Israel’s West Galilee provide the earliest evidence that modern humans co-inhabited the area with Neanderthals and could have met and interbred 55,000 years ago.
The finding—which challenges a previous hypothesis that the two species potentially met 45,000 years ago somewhere in Europe—is reported in the Advance Online Publication Nature article, “Levantine cranium from Manot Cave (Israel) foreshadows the First European modern humans.”
“It has been suspected that modern man and Neanderthals were in the same place at the same time, but we didn’t have the physical evidence. Now we do have it in the new skull fossil,” said paleontologist Bruce Latimer, from Case Western Reserve University School of Dental Medicine’s Department of Orthodontics.
The finding of Neanderthals living at other Levantine sites in the eastern Mediterranean region places the two species in the same area at about the same time. The Manot cave is located in the region where Neanderthals periodically lived, perhaps when ice sheets in Europe forced them to migrate to warmer locales, like the Levant region.
Manot is a prehistoric cave with an impressive archaeological sequence and spectacular speleothems. To date, five excavation seasons (2010-2014) have been conducted in the cave on behalf of the Israel Antiquities Authority, Tel Aviv University and Ben-Gurion University of the Negev. The cave is situated along the only land route available for ancient humans to travel out of Africa to the Middle East, Asia and Europe. Via 55,000-year-old skull links modern man in vicinity of Neanderthals.
On 26 January, asteroid 2004 BL86 zoomed past Earth at the closest distance of 1.2 million kilometres. The first images of this unusual fly-by have revealed that it’s so big, it’s got its own little moon. Scientists in the US have used NASA’s 70-metre-wide Deep Space Network antenna in California to capture the first images of asteroid 2004 BL86, which flew by Earth earlier this week, complete with its own little moon. The asteroid, measures around 325 metres across, and its moon is 70 metres across.
To give you an idea, about 16 percent of asteroids that fly-by Earth are 200 metres across or larger, and are in a binary system, which means they have a moon or a smaller asteroid orbiting it. Some near-Earth objects (NEOs) have even formed triple systems, which means they have two moons orbiting them through space.
The team was able to measure the asteroid and its moon’s sizes, shapes, rotation, surface features and roughness by producing radar images as they zoomed past. On Monday, it was about 1.2 million kilometres away from Earth – about 3.1 times the distance between Earth to the Moon -which is the closest it’s going to get to us for at least the next 200 years. And we won’t see anything this big (that we know of) getting this close to us until asteroid 1999 AN10 flies by in 2027. Via ScienceAlert.
Sometimes you’ll hear wormholes referred to as “Einstein-Rosen bridges”, referring to a 1935 paper by Billy Bob Albert Einstein and Nathan Rosen. John Archibald Wheeler and his colleagues did a lot of work on wormholes in the 1950s and ’60s, but their real entrance into the popular imagination came through Carl Sagan’s novel Contact. Through correspondence with gravitational physicist Kip Thorne, Sagan worked out a science fiction device: alien technology enabled the opening of a temporary wormhole between Earth and a distant star system, allowing the novel’s protagonist and her companions to cover many light-years of distance in a matter of hours.
As Thorne describes in his book Black Holes and Time Warps, the alien tech required some form of “exotic matter”. Sagan didn’t need to worry about the details for Contact, but Thorne did: to make a real-world wormhole to defocus light paths, you need negative energy density to keep the tunnel from collapsing. (Thorne also consulted on the recent film Interstellar, which also involves astronauts traveling via wormhole.) That follows directly from general relativity.
Nothing we know of possesses negative energy density. Dark energy, for example, has positive energy density, even though it has negative pressure. Some quantum fluctuations can be interpreted that way, though they are very tiny on the scale we’d need to build a useful wormhole. So, quantum gravity might let us have microscopic wormholes that pop in and out of existence, but that doesn’t help us travel to Vega.
In fact, it’s really hard to imagine what negative energy density even means. All matter we know about has positive energy density (guaranteed in part by E = mc2), which is why Thorne invoked hypothetical “exotic” matter in his wormhole papers, but there’s good reason to think such stuff doesn’t exist in the real world. There’s even a mathematical theorem in general relativity stating that the total energy in a volume of spacetime must be positive or zero. If there’s any negative energy density around, it must be counterbalanced by a greater amount of positive energy density in the same general region. Edited from Why wormholes (probably) don’t exist
When we talk about physics, boiling it right down to its most basic principles, we’re really just talking about the motion of the stuff around our Universe. For some objects, this is simple – some move that way, and others move the other way. But what about objects that move without moving? Or, put another way, what about objects that move, but that movement doesn’t really take them anywhere, such as a planet around a star, an electron around an atom, and our Solar System going around the gravitational centre of the Milky Way?
So we’ve got plain old ‘momentum’, which is mass x velocity, and the ‘oomph’ an object has when it’s going in a straight line; and then we’ve got ‘angular momentum’, “which is a way to explain how much oomph objects have when they’re going in circles, figuratively or literally,” says Henry in the latest episode of MinutePhysics.
The reason we care about angular momentum, he says, is that if you take a bunch of objects that are interacting, for example the Earth orbiting the Sun, you can add up all their angular momenta into one number (don’t worry, Henry shows you how to do this in the video above), and then that total value won’t change over time. It’s a constant. Unless of course, something comes in from outside to mess with the system, but you get the idea.
And here’s where it gets mind-blowing. Imagine if we looked at the Earth rotating around the Sun, calculated its angular momentum, and then suddenly took away the Sun and the rest of the Solar System. Turns out, the Earth would still have that same angular momentum about the point where the Sun was, says Henry. Of course, in the absense of the Sun’s major gravitational pull, the Earth would now be moving in a straight line, but if you calculate its angular momentum, you’re going to end up with the exact same figure that you calculated when the Earth was rotating around the Sun! Via ScienceAlert.
This is the first planetary ring system discovered outside the Solar System, and it’s got a diameter roughly 200 times larger than Saturn’s. Astronomers have found a planetary ring system with such enormous proportions, it makes Saturn’s rings look puny. The rings have formed around a young, giant exoplanet called J1407b, and they’re the first of their kind to be found outside our Solar System.
The rings were first discovered in 2012, thanks to a team led by Eric Mamajek from the University of Rochester in the US, but back then, they had no way of knowing just how big they were. They’ve since teamed up with researchers led by Matthew Kenworthy at Leiden Observatory in the Netherlands to analyse 30 individual J1407b rings to finally realise the true scale of these concentric beauties.
Turns out, each ring is tens of millions of kilometres in diameter, and the gaps between them suggest that whole satellites – or ‘exomoons’ – have formed there, just like the many tiny ’shepherd’ moons of Saturn, such as Pan and Daphnis, that continue to orbit it. The diameter of the whole system is about 120 million kilometres wide.
“This planet is much larger than Jupiter or Saturn, and its ring system is roughly 200 times larger than Saturn’s rings are today,” said Mamajek in a university press release. “You could think of it as kind of a super Saturn.” Via ScienceAlert.
Leading polymath Prof Raymond Tallis is set to use a Birmingham pub to challenge Stephen Hawking’s declaration that “philosophy is dead”. In a meeting of the Birmingham Salon at the Victoria in John Bright Street, Prof Tallis will discuss ‘Has physics destroyed philosophy?’
To do so, he will use a prepared set of notes with slides – before taking questions and answers. “I like to set out a case and not miss the steps,” said the Manchester-based retired medic who specialised in the neuroscience of strokes and epilepsy while becoming a renowned philosopher, poet, novelist and cultural critic.
Married for 42 years and a father of two, Prof Tallis said: “Hawking said ‘philosophy is now dead… because it hasn’t kept up with physics’. “But, although science is our greatest cognitive achievement, it can never explain consciousness and it will never tell us what it is like to be a human being.” Edited from an article in the Birmingham Post.
By the end of this decade the records for the world’s tallest building and highest lift are going to be broken. It has been estimated it will cost $1.2bn to build Saudi Arabia’s Kingdom Tower But this is more meaningful than just another skyscraper, in another place, that most of us will never set eyes on. This could change architecture as we know it.
There are some things most of us just don’t think about. Stepping into a lift and wondering how many floors it could travel may seem too much of a challenge to be worthwhile. Lift-maker Kone has spent many years considering this problem though.
“While elevators have enabled the rise of city skylines, the technology had reached its height limit,” explains its director of high rise technology, Santeri Suoranta. “Elevators travelling distances of more than 500m [1,640 ft] were not feasible as the weight of the [steel] ropes themselves become so large that more ropes were needed to carry the ropes themselves.”
But the company’s quest for a solution has borne fruit. After nine years of rigorous testing, it has released Ultrarope – a material composed of carbon-fibre covered in a friction-proof coating. It weighs a seventh of the steel cables, so is more energy efficient, has twice the lifespan, and most notably, it makes lifts of up to 1km (0.6 miles) in height a lot easier to build.
Other lift manufacturers, like Toshiba, Mitsubishi, Otis, Schindler, et al, have been raising their game too. They’ve been battling on in the contest to create more eco-friendly, less expensive to run, easier to install, taller and/or faster lifts. But Kone’s creation was chosen to be installed in what’s destined to become the world’s tallest building. When completed in 2020, The Kingdom Tower, in Jeddah, Saudi Arabia will stand a full kilometre in height, and will boast the world’s tallest lift at 660m (2,165ft). Edited from Lift me higher: Building the world’s tallest lift.
The idea of a smart doorbell seems plain ridiculous on paper. But when we actually checked out with German company Doorbird’s new device, we got it instantly. When someone prods your button, Doorbird sends an alert to your iOS or Android phone. Tapping that notification opens the app, which then gives you a high definition image of whoever’s stood on your doorstep.
This basically has the effect of turning your phone into a long-distance intercom – you can chat with the postie and even let them into your home or office if you’re away. Our demo guy told us that might be handy if a delivery guy wants to drop off a package, but we were a little concerned about granting a total stranger unsupervised access to our home. You’d want to pair this up with something like Netatmo’s Welcome or Manything for continued supervision.
Doorbird says that you can hook up to another webcam so you can see what they get up to directly through the Doorbird app. No word yet on whether Doorbird is getting into bed with Apple HomeKit or Samsung SmartHome, which could make webcam integration easier. With extra features such as an IR motion detector and full visitor history, the Doorbird is a nifty little device that could be great for families, especially if you don’t have a spare set of keys for visiting relatives. If anything, it’s a little on the big and bulky side, lacking the metallic finesse promised by Schlage’s Siri-compliant smart locks and Kwikset’s Bluetooth-powered Kevo. Hopefully future versions of the Doorbird will feature some sexier looks to complement its great functionality. Via Doorbird’s smart doorbell turns your phone into an intercom.