Inside the cell, an ocean of buffeting waves

Inside the cell, an ocean of buffeting waves: The cytoplasm is actually an elastic gel, it turns out, so it puts up some resistance to simple diffusion. But energetic processes elsewhere in the cell—in the cytoskeleton, especially—create random but powerful waves in the cytoplasm, pushing on proteins and organelles alike. Like flotsam and jetsam buffeted by the wakes of passing ships, suspended particles scatter much more quickly and widely than they would in a calm sea.

Harnessing the speed of light | MIT News Office

Harnessing the speed of light | MIT News Office: One of Fang’s key discoveries is finding how to beat the diffraction of light. Since light and sound waves tend to spread out when blocked by an obstacle, images and communication signals can become blurry and muddled. In his lab, Fang discovered that by breaking the diffraction barrier, light signals can be sent at 10 times greater capacity. This has allowed him to produce results on the sub-nanometer scale, with light as a machining tool providing “a new degree of precision,” he says.

Tractor Beam Created Using Water Waves� — The Physics arXiv Blog — Medium

Tractor Beam Created Using Water Waves� — The Physics arXiv Blog — Medium: This fluid jet carries any floating particles along with the waves...

But as the waves get bigger, they become unstable and their behaviour changes dramatically...

Punzmann and co say the interaction between the waves in this non-linear regime changes the direction of the jet at the centre of the wave maker. “It now pushes floaters inward, towards the wave maker and against the wave propagation,” they say. Any floaters caught in this jet, are therefore pulled.

To test this idea, Punzmann and co have recreated exactly this situation in a wave tank with an elongated wave maker. They place a ping-pong ball on the water and then measure its movement as well as the shape of the water surface and the fluid flow on the surface.

Sure enough, when the amplitude of the waves is small, the ping-pong ball moves in the same direction as the waves. But as the waves become larger, the ping-pong ball reverses direction and moves back towards the wave maker...

Tiny waves could build livers on a 'liquid template' - tech - 04 July 2014 - New Scientist

Tiny waves could build livers on a 'liquid template' - tech - 04 July 2014 - New Scientist: After adding a handful of starter pieces, such as silicon chips or small plastic beads, the researchers tuned the generator to various frequencies to create waves in the solution. Depending on their surface chemistry, the added particles spontaneously collected in either the crests or the valleys. Retuning the generator let the team switch between multiple patterns...

He and his colleagues cultured mouse cells and put them in the liquid template. The cells collected into little spheres that became the building blocks of larger geometric patterns. Adding blood clotting proteins to the saline solution locked the cells in place, an approach that the team is now investigating for growing liver tissue.

Could wireless replace wearables? | MIT News Office

Could wireless replace wearables? | MIT News Office: As described in an earlier MIT News story, the system works by transmitting a low-power wireless signal and using its reflections to track moving humans. It can do so even if the humans are in closed rooms or hiding behind a wall.

As the signal is transmitted at a wall, a portion of the signal penetrates through, reflecting off a person on the other side. However, due to all the signal interference from other objects, the team had to create technology to cancel out irrelevant reflections.

In order to monitor breathing, the technology needed to be precise: The researchers created a complex metric that approximates the subject’s volume, and then observed and amplified its changes to distinguish the breathing.

Synchronized brain waves enable rapid learning | MIT News Office

Synchronized brain waves enable rapid learning | MIT News Office:  Brain waves known as “beta bands,” produced independently by the prefrontal cortex and the striatum, began to synchronize with each other. This suggests that a communication circuit is forming between the two regions, Miller says.

“There is some unknown mechanism that allows these resonance patterns to form, and these circuits start humming together,” he says. “That humming may then foster subsequent long-term plasticity changes in the brain, so real anatomical circuits can form. But the first thing that happens is they start humming together..."

Previous studies have shown that during cognitively demanding tasks, there is increased synchrony between the frontal cortex and visual cortex, but Miller’s lab is the first to show specific patterns of synchrony linked to specific thoughts.

Unbelievable Display Technology Uses Levitating Particles as Pixels

Unbelievable Display Technology Uses Levitating Particles as Pixels: Researchers actually figured out how to levitate objects using nothing but sound years ago, but to date it's really only been with single particles. This new research, from Yoichi Ochiai, Takayuki Hoshi, and Jun Rekimoto, presented at the annual Siggraph conference, involves hundreds of tiny specks, all strategically arranged in real-time to form images, and even moving animations.

A Tractor Beam Made Of Sound Waves | Popular Science

A Tractor Beam Made Of Sound Waves | Popular Science: The device consists of about a thousand ultrasound emitters, placed underwater. When turned on, scientists used it to tug along centimeter-sized objects (roughly half and inch), such as a small hollow triangular shape. Normally the effect of sending acoustic beams at something would tend to push it away. But the scientists found that by precisely controlling the angle of sound waves, they can create a low pressure zone in front of the object, thus pulling it closer.

Scientists May Have Decoded One of the Secrets to Superconductors | Science | WIRED

Scientists May Have Decoded One of the Secrets to Superconductors | Science | WIRED: ...ripples of electrons inside the superconductors that are called charge density waves. The fine-grained structure of the waves, reported in two new papers by independent groups of researchers, suggests that they may be driven by the same force as superconductivity. Davis and his colleagues directly visualized the waves in a study posted online in April...

It seemed possible that if the force shaping electrons into charge density waves could be suppressed, its rival, the force that forms superconducting pairs, would flourish. But some researchers argued that the ripples of electrons were merely a surface anomaly and irrelevant to superconductivity.

The community remained divided until 2012, when two groups using a technique called resonant X-ray scattering managed to detect charge density waves deep inside cuprates, cementing the importance of the waves...

Pseudogap theory puts physicists closer to high temperature superconductors

Pseudogap theory puts physicists closer to high temperature superconductors: The theory explains the transition phase to superconductivity, or "pseudogap" phase, which is one of the last obstacles to developing the next generation of superconductors and one of the major unsolved problems of theoretical condensed matter physics...

This new study found that YBa2Cu3O6+x oscillates between two quantum states during the pseudogap, one of which involves charge-density wave fluctuations. These periodic fluctuations in the distribution of the electrical charges are what destabilize the superconducting state above the critical temperature.

First step towards 'programmable materials'

First step towards 'programmable materials': The working model used by the researchers consists of a one-meter by one-centimeter aluminum plate that is one millimeter thick. This sheet-metal strip can vibrate at different frequencies. In order to control the wave propagation, ten small aluminum cylinders (7 mm thick, 1 cm high) are attached to the metal. Between the sheet and the cylinders sit piezo discs, which can be stimulated electronically and change their thickness in a flash. This ultimately enables the team headed by project supervisor Andrea Bergamini to control exactly whether and how waves are allowed to propagate in the sheet-metal strip. The aluminum strip thus turns into a so-called adaptive phononic crystal – a material with adaptable properties.

Scientists twist sound with metamaterials

Scientists twist sound with metamaterials: ...the team reports a simple design for a device, called an acoustic field rotator, which can twist wavefronts inside it so that they appear to be propagating from another direction...

Another surprise the team discovered was that acoustic and electromagnetic rotators can be designed based on the same principles. In this case, the researchers used anisotropic metamaterials, which possess physical properties that differ along different directions.

Whoa: Watch Scientists Use Sound Waves to Make Things Levitate | Wired Design | Wired.com

Whoa: Watch Scientists Use Sound Waves to Make Things Levitate | Wired Design | Wired.com: ...scientists have been experimenting with acoustic levitation for decades, using sound waves to suspend materials in mid-air. What’s new here, though, is the ability to move those materials in three dimensions.

That’s made possible by the unique arrangement of the speakers themselves. Where former setups bounced sound waves off a solid plate, the Tokyo researchers instead use four panels of speakers, all facing each other. These walls combine to create an “ultrasonic focal point,” which can be moved—along with the object trapped in it—by adjusting the output from each speaker array.

New material gives visible light an infinite wavelength

New material gives visible light an infinite wavelength: The way light travels through matter is dependent on the material permittivity: the resistance of a material against the electric fields of light waves. Because the permittivity of silver is negative and that of silicon nitride is positive, the combined material has a permittivity which is effectively equal to zero. Therefore, it seems that the light experiences zero resistance, and propagates with an infinite phase velocity. The wavelength of the light is nearly infinite.

Quantum effects in nanowires at room temperature

Quantum effects in nanowires at room temperature: Further examination of the nanowires formed produced namely a surprising discovery: nearly all the wires that were formed had a length of 4.8 nanometers, or multiples thereof, and they nearly all contained twelve iridium atoms, or a multiple thereof. The researchers found the explanation for this in quantum effects. The wires of 4.8 nanometers (or multiples thereof) appear to be electronically stabilized by conduction electrons whose (half) wavelength (or a multiple thereof) fits precisely in the nanowire. The existence of these standing electron waves in the nanowires could be demonstrated experimentally. As this stabilizing effect will not occur in nanowires of iridium of a different length, they are formed more slowly.

Researchers slow light to a crawl in liquid crystal matrix

Researchers slow light to a crawl in liquid crystal matrix: The new approach... uses little power, does not require an external electrical field, and operates at room temperature, making it more practical than many other slow light experiments...


The key to achieving a significant drop-off in speed is to take advantage of the fact that when light travels as a pulse it is really a collection of waves, each having a slightly different frequency, says Bortolozzo. However, all the waves in the pulse must travel together. Scientists can design materials to be like obstacles courses that "trip up" some of the waves more than others. In order to exit the material together, the pulse must wait until it can reconstitute itself...


They added a chemical component that twisted the liquid crystal molecules into a helical shape and then added dye molecules that nestled in the helical structures. The dye molecules change their shape when irradiated by light, altering the optical properties of the material and hence changing the relative velocities of the different wave components of the light pulse as it travelled through. In addition, the helical structure of the liquid crystal matrix ensures a long lifetime of the shape-shifted dyes, which makes it possible to "store" a light pulse in the medium and later release it on demand...

When fluid dynamics mimic quantum mechanics | KurzweilAI

When fluid dynamics mimic quantum mechanics | KurzweilAI: In the experiments reported in PRE, the researchers mounted a shallow tray with a circular depression in it on a vibrating stand. They filled the tray with a silicone oil and began vibrating it at a rate just below that required to produce surface waves.

They then dropped a single droplet of the same oil into the bath. The droplet bounced up and down, producing waves that pushed it along the surface.

The waves generated by the bouncing droplet reflected off the corral walls, confining the droplet within the circle and interfering with each other to create complicated patterns. As the droplet bounced off the waves, its motion appeared to be entirely random, but over time, it proved to favor certain regions of the bath over others...

The statistical description of the droplet’s location is analogous to that of an electron confined to a circular quantum corral and has a similar, wavelike form.

A scientific experiment is able to create a wave that is frozen in time

A scientific experiment is able to create a wave that is frozen in time "A wave is a deformation in the surface of a liquid that moves at a speed that is independent of that liquid," the researchers explain... "In our case, what occurs is actually the opposite: the water moves very rapidly (at several meters per second), but the wave moves at a speed of zero...

In order to recreate this phenomenon, the scientists constructed a small canal in a laboratory at the University. The prototype is relatively simple, they say: it consists of a semi-submerged panel with a square corner that partially obstructs the flow in a tank of water that is approximately the length of a van.

Physicists Build World's First "Magnetic Hose" For Transmitting Magnetic Fields

Physicists Build World's First "Magnetic Hose" For Transmitting Magnetic Fields: Navau and co point out that a static magnetic field can be thought of as a wave with an infinite wavelength so in theory it ought to be possible to control it with a metamaterial in the same way as electromagnetic waves...


Their conclusion is that a “magnetic hose” consisting of concentric tubes of superconducting and ferromagnetic materials ought to do the trick. They say that a tube consisting of 20 concentric rings that is about ten times longer than it is wide, should transmit about 90 per cent of a magnetic field at one end to the other.  Indeed, a tube of just 2 concentric rings should transmit about 75 per cent.

Peaceful matter-antimatter pairing looks more real

Peaceful matter-antimatter pairing looks more real: The first signs of these Majorana fermions came last year in the form of a current that appeared at zero voltage in a nano-size wire...
They created a similar set-up but this time ramped the voltage up and down and shortened the wire. The plan was to cause the quantum waves associated with each fermion to overlap and constructively interfere, creating two extra peaks in current. Sure enough, the team saw two more blips...