Is time moving forward or backward? Computers learn to spot the difference | Science/AAAS | News

Is time moving forward or backward? Computers learn to spot the difference | Science/AAAS | News: To find out, she and her collaborators broke down 180 YouTube videos into square patches of a few hundred pixels, which they further divided into four-by-four grids. Combining standard techniques for discovering objects in still photographs with motion detection algorithms, the researchers identified 4000 typical patterns of motion, or “flow words,” across a grid’s 16 cells. The gentle downward drifting of snowflakes, for example, would be one flow word. From those patterns, the team created flow word descriptions of each video along with three other versions—a time-reversed version, a mirror-image version, and a mirror-image and time-reversed version. Then, they made a computer program watch 120 of these clips, training it to identify which flow words best revealed whether a video ran forward or backward.

When they tested their program on the remaining 60 videos, the trained computers could correctly determine whether a video ran forward or backward 80% of the time...  A closer analysis found that flow words associated with divergence (water splashing outward as someone dives into a pool) or dissipation (a steam train’s exhaust spreading out in air) were especially good indicators of the direction in which time was moving.

Elastic invisibility cloak hides materials from touch sense

Elastic invisibility cloak hides materials from touch sense: The metamaterial is a crystalline material structured with sub-micrometer accuracy. It consists of needle-shaped cones, whose tips meet. The size of the contact points is calculated precisely to reach the mechanical properties desired. In this way, a structure results, through which a finger or a measurement instrument cannot feel its way.

In the invisibility cloak produced, a hard cylinder is inserted into the bottom layer. Any objects to be hidden can be put into its cavity. If a light foam or many layers of cotton would be placed above the hard cylinder, the cylinder would be more difficult to touch, but could still be felt as a form. The metamaterial structure directs the forces of the touching finger such that the cylinder is hidden completely...

Quantum theory reveals puzzling pattern in how people respond to some surveys

Quantum theory reveals puzzling pattern in how people respond to some surveys: The survey changed the order in which these questions were asked between respondents and, as expected, there were question-order effects found. When respondents were asked about Clinton first, 49 percent said that both Clinton and Gore were trustworthy. But when respondents were asked about Gore first, 56 percent said that both were trustworthy.

The pattern that quantum theory predicted – and that the researchers found – was that the number of people who switch from "yes-yes" to "no-no" when the question order is reversed must be offset by the number of people who switch in the opposite direction...

The researchers called this phenomenon "quantum question equality." They found it in every one of the surveys studied.

The Flaw Lurking In Every Deep Neural Net

The Flaw Lurking In Every Deep Neural Net: "For all the networks we studied, for each sample, we always manage to generate very close, visually indistinguishable, adversarial examples that are misclassified by the original network."
To be clear, the adversarial examples looked to a human like the original, but the network misclassified them. You can have two photos that look not only like a cat but the same cat, indeed the same photo, to a human, but the machine gets one right and the other wrong.

A Beautiful Mind: Brain Injury Turns Man Into Math Genius�

A Beautiful Mind: Brain Injury Turns Man Into Math Genius�: Padgett recalls being knocked out for a split second and seeing a bright flash of light...

Soon after the attack... he noticed that everything looked different. He describes his vision as "discrete picture frames with a line connecting them, but still at real speed." If you think of vision as the brain taking pictures all the time and smoothing them into a video, it's as though Padgett sees the frames without the smoothing. In addition, "everything has a pixilated look," he said.

A Startup Plans to Add Feeling to Gesture Control | MIT Technology Review

A Startup Plans to Add Feeling to Gesture Control | MIT Technology Review: For the study, participants placed a hand, palm facing up, on a table below an array of 64 ultrasound transducers set in an eight-by-eight grid...

In one experiment, the ultrasound array focused feedback on 25 different parts of the hand to see if participants could pinpoint differences in where, precisely, they felt the waves. In the second, the array emitted waves in a way meant to feel like a line of continuous motion in a specific direction across the hand...

... research indicated that that the smallest virtual shape people could reliably feel was about two centimeters square.

How To Build A Quantum Telescope — Medium

How To Build A Quantum Telescope — Medium: Her idea is to use the astrophysical photons to stimulate the production of an entangled pair, inside a telescope. The first of this pair then hits the detector, generating an image. But the other can be used to increase the information known about the first, thereby increasing the resolution and beating the diffraction limit.

A Blind Robot That Navigates By Touch | Popular Science

A Blind Robot That Navigates By Touch | Popular Science: When a whisker touches something, it bends backward, pushing a magnet at its base. A magnetic sensor detects the displacement and sends it to Shrewbot’s computer processor. Shrewbot uses these touch signals to create a picture of its environment and distinguish shapes and textures.

What We Can Learn From the Quantum Calculations of Birds and Bacteria - Wired Science

What We Can Learn From the Quantum Calculations of Birds and Bacteria - Wired Science: We can now show that a single electronic excitation acting as a probability amplitude wave can simultaneously sample the various molecular paths connecting the antenna cells to the reaction center. The excitation effectively “picks” the most efficient route from leaf surface to sugar conversion site from a quantum menu of possible paths. This requires that all possible states of the traveling particle be superposed in a single, coherent quantum state for tens of femtoseconds.

We have seen this remarkable phenomenon in the green sulphur bacteria, but humans have not yet figured out how it is that nature can stabilize a coherent electronic quantum state in such complex systems for such long periods of time...

Remarkably, it seems that these photosynthesizing bacteria can actually use decoherence to speed up the transfer of electronic information by accessing vibrational energies in the protein bath surrounding the biological-quantum wire without losing the integrity of the information...

It seems that quantum mechanical processes in the avian eye send signals to the brain that are sensitively dependent on the angle of change in magnetic field inclination, thereby allowing the bird to map routes. The hypothesis is that pairs of light-absorbing molecules in the bird retina produce quantum mechanically entangled electrons whose quantum mechanical state depends on the angular inclination of the field and which catalyze chemical reactions that send differently valued signals to the brain depending upon the degree of inclination.

Brain imaging spots our abstract choices before we do

Brain imaging spots our abstract choices before we do:  Kreiman discovered that electrical activity in the supplementary motor area, involved in initiating movement, and in the anterior cingulate cortex, which controls attention and motivation, appeared up to 5 seconds before a volunteer was aware of deciding to press the button (Neuron, doi.org/btkcpz). This backed up earlier fMRI studies by John-Dylan Haynes of the Bernstein Center for Computational Neuroscience in Berlin, Germany, that had traced the origins of decisions to the prefrontal cortex a whopping 10 seconds before awareness...

If this kind of "mind-reading" is possible, a new study by Haynes, published this week and also presented at the meeting, suggests that it may not be restricted to decisions about moving a finger. Using fMRI, Haynes has found that the very brain areas involved in deciding to move are also active several seconds before a more abstract decision, like whether to add or subtract a series of numbers.

Virtual reality creates infinite maze in a single room - tech - 05 April 2013 - New Scientist

Virtual reality creates infinite maze in a single room - tech - 05 April 2013 - New Scientist: The illusion created by the VR system is strong enough that people trying it do not realise that they are effectively walking around in circles. "People think they are walking in much larger environments..."

Bumblebees Sense Electric Fields in Flowers

Bumblebees Sense Electric Fields in Flowers: Finally, the team released bumblebees into an arena with artificial flowers, half of which were positively charged and carried a sucrose reward, and the other half of which were grounded and carried a bitter solution. Over time, the bees increasingly visited the rewarding charged flowers.

But when the researchers turned off the electrical charge on the flowers and re-released the trained bees, the insects visited rewarding flowers only about half of the time, as they would have by random chance.

Musical brains smash audio algorithm limits - New Scientist - New Scientist

Musical brains smash audio algorithm limits: ...To investigate, Jacob Oppenheim and Marcelo Magnasco of Rockefeller University in New York turned to the Gabor limit, a part of the Fourier transform's mathematics that makes the determination of pitch and timing a trade-off...

The pair reasoned that if people's hearing obeyed the Gabor limit, this would be a sign that they were using the Fourier transform. But when 12 musicians, some instrumentalists, some conductors, took a series of tests, such as judging slight changes in the pitch and duration of sounds at the same time, they beat the limit by up to a factor of 13.

Quantum theory of smell causes a new stink

Quantum theory of smell causes a new stink: In 1996 he proposed that a smell receptor would only fire when a molecule vibrated at the right frequency. These vibrations provide enough energy to trigger a quantum tunneling effect, causing an electron to pass across the receptor and trigger a smell.

One way to test the theory is replacing the hydrogen atoms in a molecule with deuterium, a hydrogen isotope with a nucleus of a neutron and a proton, rather than just a proton. The shape of the molecule barely changes, but the added neutrons alter the frequency of its vibrations.

A Slower Speed of Light | MIT Game Lab

A Slower Speed of Light | MIT Game Lab; A Slower Speed of Light is a first-person game prototype in which players navigate a 3D space while picking up orbs that reduce the speed of light in increments. Custom-built, open-source relativistic graphics code allows the speed of light in the game to approach the player's own maximum walking speed. Visual effects of special relativity gradually become apparent to the player, increasing the challenge of gameplay. These effects, rendered in realtime to vertex accuracy, include the Doppler effect (red- and blue-shifting of visible light, and the shifting of infrared and ultraviolet light into the visible spectrum); the searchlight effect (increased brightness in the direction of travel); time dilation (differences in the perceived passage of time from the player and the outside world); Lorentz transformation (warping of space at near-light speeds); and the runtime effect (the ability to see objects as they were in the past, due to the travel time of light).

A Big Magnet in a Small Fish - ScienceNOW

A Big Magnet in a Small Fish - ScienceNOW: Now, for the first time in any animal, scientists have isolated magnetic cells in the fish that respond to these fields...
The challenge in isolating magnetic cells is that they are few and far between—if they were clustered together they would interfere with each other's magnetism. "If you have a tissue containing these cells, it's likely that only one out of ten thousand cells is magnetic..."
To isolate magnetic cells from their non-magnetic neighbors, Winklhofer and his collaborators placed a suspension of rainbow trout (Oncorhynchus mykiss) cells under a microscope that had a magnet rotating around the stage that the sample sat on...
And surprisingly, the magnetism in each cell was tens to hundreds of times stronger than researchers had hypothesized, says Winklhofer...

CultureLab: Cyborg makes art using seventh sense

CultureLab: Cyborg makes art using seventh sense: Colour is basically hue, saturation, and light. Right now, I can see light in shades of grey, but I can’t see its saturation or hue. This gadget detects the light’s hue, and converts the light into a sound frequency that I can hear as a note [wavelength is inversely proportional to frequency so it can easily convert the wavelength of the light into a sound frequency].
It also translates the saturation of the colour into volume. So if it’s a vivid red I will hear it more loudly.

All the translation happens in a chip on the back of my neck - it's all held by pressure onto the bone. It stays there all the time when I go to bed. In September I'm having it osteointegrated - which means that part of the device will be put inside my bone in a hospital in Barcelona and then the sound will resonate much better then. It took a year to convince them that it was ethical and part of me.

Liquid-Filled Robot Finger More Sensitive to Touch Than a Human's

Liquid-Filled Robot Finger More Sensitive to Touch Than a Human's: A flexible, spongy skin complete with ridges (like a fingerprint) is stretched over a liquid filling. As it slides over a surface, the skin vibrates in ways that are distinctly tied to the texture of the material it is touching. A hydrophone inside the core of the finger picks up these vibrations and uses them to distinguish between materials...

The researchers recreated this way of discerning between exploratory movements via an algorithm that allows the robot to zero in on the best exploratory movements for appraising any material set in front of it at random. The result: when presented with 117 materials gathered from fabric, stationary, and hardware stores, the robot correctly identified them 95 percent of the time using no sensory input but touch.

Pigeons may ‘hear’ magnetic fields : Nature News & Comment

Pigeons may ‘hear’ magnetic fields : Nature News: Individual neurons in birds' brains can relay crucial information about Earth’s magnetic field...

For their latest research, the subject of today's Science paper, Wu and Dickman restrained seven homing pigeons (Columba livia) and placed them in a dark room. A magnetic field was created to cancel Earth’s field, and the researchers then monitored the birds’ brain activity while creating and rotating carefully controlled artificial magnetic fields around the pigeons.

The authors found that vestibular neurons — which are linked to balance systems in the inner ear — fired differentially in response to alterations in the field’s direction, intensity and polarity, and that these cells were especially sensitive to the bandwith that covers Earth’s geo-magnetic field...

“I would say now there are three potential places where magnetoreceptors may rest...”  These are the beak, the eyes and the ears.

Wait, maybe birds don't have compasses in their beaks after all

Wait, maybe birds don't have compasses in their beaks after all: New research published in Nature has shown that while there are indeed iron rich cells in a pigeon's beak, the previous research has entirely miscategorized their purpose. The researchers mapped the location of these cells in the beak, and found much greater variation in number and location than would work with being magnetic receptors.

Rather, these clusters are iron-rich macrophage cells, don't contain magnetite, and are most likely part of the pigeon's immune system, and used for iron homeostasis. It turns out these iron-laden cells are found throughout pigeons, and that means our interpretation of them as the primary method for these birds to sense magnetic fields is wrong.