Stephen Hawking challenges the notion of black holes as we know them in a new paper (still awaiting peer-review)
“’There is no escape from a black hole in classical theory,’ Hawking told Nature. Quantum theory, however, ‘enables energy and information to escape from a black hole’. A full explanation of the process, the physicist admits, would require a theory that successfully merges gravity with the other fundamental forces of nature. But that is a goal that has eluded physicists for nearly a century. 'The correct treatment,’ Hawking says, 'remains a mystery.’Hawking’s new work is an attempt to solve what is known as the black-hole firewall paradox, which has been vexing physicists for almost two years, after it was discovered by theoretical physicist Joseph Polchinski of the Kavli Institute and his colleagues…. (read more)”
Star Hen 2-427 more commonly known as WR 124 and the nebula M1-67 which surrounds it, found in the constellation of Sagittarius; ESA/Hubble & NASA, Judy Schmidt
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Reid Wiseman Vines: That’s not the Sun, it’s the Moon setting on a gorgeous night.
A remarkable experiment has successfully seen the effects of “quantum motion” at a relatively large scale. These are essentially tiny vibrations caused on an atomic level when an object otherwise appears to be stationary. Among its many implications, the research – which was also able to temporarily stop the effect – could aid the hunt for elusive ripples in space-time called gravitational waves.
The study, published in the journal Science, was carried out by a team of researchers from the California Institute of Technology (Caltech) and collaborators. In classical physics, an object – such as a ball in a bowl – will eventually come to rest as the forces of gravity and friction act upon it. But in quantum mechanics, which governs the behavior of matter and light at an atomic scale, nothing is ever truly at rest.
This means that everything has an extremely small quantum noise, or motion; tiny vibrations at an atomic scale. In this experiment, the researchers were able to observe the effect not just at an atomic level, but at a larger micrometer-scale and, for the first time, control the effect.
To detect it, they placed a flexible aluminum plate on top of a silicon substrate. A superconducting electrical circuit was then used to vibrate the plate at 3.5 million times per second. Subsequently cooling the plate to 0.01 Kelvin (-273.14°C, -459.65°F) reduced the vibrations in a classical sense to zero, but probing it with microwave fields showed a small quantum motion – roughly the diameter of a proton, or 10,000 times smaller than a hydrogen atom.
“What we have found is that the motion of a micron scale object requires a quantum description,” co-author Keith Schwab from Caltech told IFLScience. “Classical physics just can’t capture the quantum noise we see.”
According to Schwab, the noise is an “unavoidable consequence of the Heisenberg Uncertainty Principle,” which essentially states that everything behaves like a particle and a wave at the same time. However, the team found that by carefully applying a controlled microwave field, they could reduce the motion in certain places, at the cost of making it much larger elsewhere. This technique is known as quantum squeezing.
Read more ~ IFL Science
Photo credit: agsandrew/Shutterstock.
One sheet, 15 centimetres in diameter and a few tenths of a millimetre thick can store as much as 1 F, which is similar to the supercapacitors currently on the market. The material can be recharged hundreds of times and each charge only takes a few seconds.
It’s a dream product in a world where the increased use of renewable energy requires new methods for energy storage – from summer to winter, from a windy day to a calm one, from a sunny day to one with heavy cloud cover.
”Thin films that function as capacitors have existed for some time. What we have done is to produce the material in three dimensions. We can produce thick sheets,” says Xavier Crispin, professor of organic electronics and co-author to the article just published in Advanced Science.
Other co-authors are researchers from KTH Royal Institute of Technology, Innventia, Technical University of Denmark and the University of Kentucky.
The material, power paper, looks and feels like a slightly plasticky paper and the researchers have amused themselves by using one piece to make an origami swan – which gives an indication of its strength.
The structural foundation of the material is nanocellulose, which is cellulose fibres which, using high-pressure water, are broken down into fibres as thin as 20 nm in diameter. With the cellulose fibres in a solution of water, an electrically charged polymer (PEDOT:PSS), also in a water solution, is added. The polymer then forms a thin coating around the fibres.
”The covered fibres are in tangles, where the liquid in the spaces between them functions as an electrolyte,” explains Jesper Edberg, doctoral student, who conducted the experiments together with Abdellah Malti, who recently completed his doctorate.
The new cellulose-polymer material has set a new world record in simultaneous conductivity for ions and electrons, which explains its exceptional capacity for energy storage. It also opens the door to continued development toward even higher capacity. Unlike the batteries and capacitors currently on the market, power paper is produced from simple materials – renewable cellulose and an easily available polymer. It is light in weight, it requires no dangerous chemicals or heavy metals and it is waterproof.
The Power Papers project has been financed by the Knut and Alice Wallenberg Foundation since 2012.
”They leave us to our research, without demanding lengthy reports, and they trust us. We have a lot of pressure on us to deliver, but it’s ok if it takes time, and we’re grateful for that,” says Professor Magnus Berggren, director of the Laboratory of Organic Electronics at Linköping University.
The new power paper is just like regular pulp, which has to be dehydrated when making paper. The challenge is to develop an industrial-scale process for this.
”Together with KTH, Acreo and Innventia we just received SEK 34 million from the Swedish Foundation for Strategic Research to continue our efforts to develop a rational production method, a paper machine for power paper,” says Professor Berggren.
Power paper – Four world records
Highest charge and capacitance in organic electronics, 1 C and 2 F (Coulomb and Farad).
Highest measured current in an organic conductor, 1 A (Ampere).
Highest capacity to simultaneously conduct ions and electrons.
Highest transconductance in a transistor, 1 S (Siemens)
Publication:
An Organic Mixed Ion-Electron Conductor for Power Electronics, Abdellah Malti, Jesper Edberg, Hjalmar Granberg, Zia Ullah Khan, Jens W Andreasen, Xianjie Liu, Dan Zhao, Hao Zhang, Yulong Yao, Joseph W Brill, Isak Engquist, Mats Fahlman, Lars Wågberg, Xavier Crispin and Magnus Berggren. Advanced Science, DOI 10.1002/advs.201500305
Linköping University
Non-Newtonian fluids are capable of all kinds of counter-intuitive behaviors. The animations above demonstrate one of them: the tubeless or open siphon. Once the effect is triggered by removing some of the liquid, the fluid quickly pours itself out of the beaker. This is possible thanks to the polymers in the liquid. The falling liquid pulls on the fluid left behind in the beaker, which stretches the polymers in the fluid. When stretched, the polymers provide internal tension that opposes the extensional force being applied. This keeps the fluid in the beaker from simply detaching from the falling liquid. Instead, it flows up and over the side against the force of gravity, behaving rather more like a chain than a fluid! (Image credit: Ewoldt Research Group, source)
It’s a bad day both for Albert Einstein and for hackers. The most rigorous test of quantum theory ever carried out has confirmed that the ‘spooky action at a distance’ that the German physicist famously hated — in which manipulating one object instantaneously seems to affect another, far away one — is an inherent part of the quantum world.
The experiment, performed in the Netherlands, could be the final nail in the coffin for models of the atomic world that are more intuitive than standard quantum mechanics, say some physicists. It could also enable quantum engineers to develop a new suite of ultrasecure cryptographic devices.
“From a fundamental point of view, this is truly history-making,” says Nicolas Gisin, a quantum physicist at the University of Geneva in Switzerland.
Continue Reading.
By NASA
NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission has identified the process that appears to have played a key role in the transition of the Martian climate from an early, warm and wet environment that might have supported surface life to the cold, arid planet Mars is today.
(excerpt - click the link for the complete article and cool video animation)
Three quarks for Muster Mark*! And for every proton and neutron, too… right?
Not so fast. You might have learned that every proton and neutron is made of elementary particles called quarks, and that each of the familiar subatomic bits that make up the nucleus of atoms is built out of precisely three of the quirky, quarky sub-subatomic bunch.
This great video from The Physics Girl explains why that idea doesn’t quite add up to what’s really going on at matter’s smallest scales. Plus, CANDY! I love candy! Just wait ‘til you get to the part about how much mass is inside of a proton compared to the number of particles. Mind = blown, Einstein.
*Funny historical note: At the beginning of the video, Dianna asks why “quark” is spelled the way it is. It looks like it should be pronounced “kwahrk,” but we clearly pronounce it “kwork”. Well, Murray Gell-Mann, the physicist who first theorized the existence of these elementary particles, had already picked out the name he wanted, a made-up word that he pronounced “kwork”, but with no idea how he should spell it. Then, while reading Finnegan’s Wake by James Joyce, he stumbled on the following passage:
Three quarks for Muster Mark! Sure he has not got much of a bark And sure any he has it’s all beside the mark.
Gell-Mann stuck to his guns on the “kwork” pronunciation, despite the fact that it’s obviously supposed to rhyme with “Mark”, but seeing that Joyce had stumbled upon the same rule of three quarks that the universe had, he couldn’t pass it up. Quantum literature!
* (You look inside...) * (Inside the joke book is a quantum physics book.)
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