‘Mind Uploading’ & Digital Immortality May Be Reality By 2030 : Dr. Michio Kaku

    There are two major questions surrounding the concept of mind uploading. There is the question of feasibility: Can we build a model of a brain complete enough to allow a conscious mind to emerge? The other question is concerned with identity. Some people argue that, if a copy of a conscious mind is identical by all measures (ignoring the fact that one is biological and the other is neuromorphic software/hardware) it should be thought of as a continuation of the mind that was mapped and uploaded. Others argue that a copy cannot be considered the same as the original, so the newly awakened consciousness must be another person.






A new way to make laser-like beams using 1,000x less power

laser
With precarious particles called polaritons that straddle the worlds of light and matter, University of Michigan researchers have demonstrated a new, practical and potentially more efficient way to make a coherent laser-like beam.

They have made what's believed to be the first polariton laser that is fueled by electrical current as opposed to light, and also works at room temperature, rather than way below zero.
Those attributes make the device the most real-world ready of the handful of polariton lasers ever developed. It represents a milestone like none the field has seen since the invention of the most common type of laser – the semiconductor diode – in the early 1960s, the researchers say. While the first lasers were made in the 1950s, it wasn't until the semiconductor version, fueled by electricity rather than light, that the technology took off.
This work could advance efforts to put lasers on computer circuits to replace wire connections, leading to smaller and more powerful electronics. It may also have applications in medical devices and treatments and more.
The researchers didn't develop it with a specific use in mind. They point out that when conventional lasers were introduced, no one envisioned how ubiquitous they would become. Today they're used in the fiber-optic communication that makes the Internet and cable television possible. They are also in DVD players, eye surgery tools, robotics sensors and defense technologies, for example.
A polariton is part light and part matter. Polariton lasers harness these particles to emit light. They are predicted to be more energy efficient than traditional lasers. The new prototype requires 1,000 times less electricity to operate than its conventional counterpart made of the same material.
"This is big," said Pallab Bhattacharya, the Charles M. Vest Distinguished University Professor of Electrical Engineering and Computer Science and the James R. Mellor Professor of Engineering at U-M. "For the past 50 years, we have relied on lasers to make coherent light and now we have something else based on a totally new principle."
Bhattacharya's system isn't technically a laser. The term was initially an acronym for Light Amplification by Stimulated Emission of Radiation. Polariton lasers don't stimulate radiation emission. They stimulate scattering of polaritons.
In a typical laser, light—or more often electrical current— is pumped into a material called a gain medium that's designed to amplify the signal. Before the pumping begins, most of the electrons in the gain medium are in their least energetic state, also known as the ground state. Once the light or current hits them, the electrons absorb that energy and move to a higher-energy state. At some point, more electrons are high-energy than are low-energy and the device is said to have achieved a "population inversion." Now any light or current that goes in has the opposite effect on the excited electrons. It kicks them down to the ground state and releases pent-up light in the process.
Polariton lasers don't rely on these population inversions, so they don't need a lot of start-up energy to excite electrons and then knock them back down. "The threshold current can be very small, which is an extremely attractive feature," Bhattacharya said.
He and his team paired the right material – the hard, transparent semiconductor gallium nitride – with a unique design to maintain the controlled circumstances that encourage polaritons to form and then emit light.
How it works
A polariton is a combination of a photon or light particle and an exciton – an electron-hole pair. The electron is negatively charged and the hole is technically the absence of an electron, but it behaves as if it were positively charged. Excitons will only fuse with light particles under just the right conditions. Too much light or electrical current will cause the excitons to break down too early. But with just enough, polaritons will form and then bounce around the system until they come to rest at their lowest energy level in what Bhattacharya describes as a coherent pool. There, the polaritons decay and in the process, release a beam of single-colored light.
The beam they demonstrated was ultraviolet and very low power – less than a millionth of a watt. For context, the laser in a CD player is about one-thousandth of a watt.
"We're thrilled," said Thomas Frost, a doctoral student in electrical and computer engineering. "This is the first really practical polariton laser that could be used on chip for real applications."
The design the team used helped them achieve the beam with an electrical rather than light input signal. Getting the electrical current into the system requires electrodes sandwiching the gallium nitride and several layers of mirrors to render the electrical signal useable. Other groups' approaches put the electrodes outside the mirrors. Bhattacharya said it was tough to get the signal strong enough under those circumstances. So he deconstructed the sandwich. He put the mirrors on the sides of the gallium nitride and left the electrodes on the top and bottom.


Read more at: http://phys.org/news/2014-06-laser-like-1000x-power.html#jCp


Just Add Water, and Silicon Folds Into Origami Shapes

silicon cut-out
Researchers created microscopic cubes, pyramids, half soccer-ball-shaped bowls
 and long triangular Toblerone-like structures, all of which fold themselves when
 wetted by a drop of water. Credit: A. Legrain, et. al, University of Twente

Remember those elementary geometry lessons that involved cutting out a pattern from a worksheet and folding along the dotted lines to create a cube, cone or cylinder? Well, fully grown scientists are still doing the same thing, only on a microscopic scale.
Researchers from the University of Twente in the Netherlands have created self-folding, microscopic structures out of silicon nitrate. When the silicon is exposed to water, like magic, the flat cutouts fold into cubes, hexagonal bowls, pyramids and even Toblerone-shaped triangular tubes, all no bigger than a grain of sand.
The research team’s shapes could someday be deployed in a variety of biomedical applications where stealth and accuracy are desired.
Knowing How to Fold’em
To coax a 2-D silicon cutout into 3-D, researchers rely on the cohesive properties of water molecules. A microscopic water droplet beneath the silicon causes the creases to pull together to create the geometric object.
Researchers showed they could vary the amount of water in channels beneath the silicon to open and close the shape up to 60 times without showing signs of wear. Although this team wasn’t the first to demonstrate hydro-folding silicon, they were the first to develop a replicable, controllable technique to deliver the water. Up to now, scientists added droplets of water by hand, and their shapes could only be folded once.
They described their water-based folding system in theJournal of Applied Physics.
Shaping Up, and Shipping Out
Researchers believe the new folding system will make assembling tiny shapes cheaper and thus more practical. They believe these microscopic structures could be used to deliver medication in a targeted fashion, or to perform micro-biopsies.
Check out the video below to see how water and silicon come together to work their magic.


3000 year old trousers discovered in Chinese grave oldest ever found

3000 year old trousers discovered in Chinese grave oldest ever found
     A team of researchers working in the ancient Yanghai graveyard in China's Tarim Basin has uncovered what appears to be the earliest example of trouser wearing. The research team has published a paper in the journal Quaternary International describing the pants and why they were likely developed to assist with riding horses.
The Tarim Basin in western China is host to the famous Yanghai tombs, a large ancient burial ground that dates back thousands of years—thus far over 500 individual gravesites have been excavated. In this latest find, two adult males (believed to be herders and warriors) both approximately 40 years old at the time of death, were wearing trousers. Carbon dating put the age of the material at approximately 3000 years ago, making the find the oldest known instance of trouser wearing.
In the tomb, along with the bodies, were a horse bit made of wood, a whip, a bow and a battle-axe. These artifacts along with the cut of the pants, suggest the trousers were created and worn to allow for easier horse riding over long periods of time. They also suggest that trouser creation had matured to a level that allowed for custom tailoring. Both specimens were created from three pieces of material (sized to fit a particular individual) one for each leg and a crotch piece—both also had an associated belt made of strings. No cutting was required. Each pant leg also had cross stitching that appeared to serve a purely decorative function.
Many historians believe that trousers were invented as a means of riding horses—riding for a long time can cause skin irritation and discomfort. The trousers worn by horse riders likely migrated to other people, the theory goes, who chose to adopt them for unknown reasons. Its likely modifications were made because riding pants are not particularly comfortable for walking or engaging in everyday life. Prior to trousers, people of both genders tended to wear tunics, robes, togas, etc. It is also generally believed that horse riding by humans began approximately 4000 years ago, which suggests trouser wearing began long before the two men in the Yanghai gravesite donned theirs.

More information: The invention of trousers and its likely affiliation with horseback riding and mobility: A case study of late 2nd millennium BC finds from Turfan in eastern Central Asia, Quaternary International, Available online 22 May 2014 dx.doi.org/10.1016/j.quaint.2014.04.056
Abstract
Here, we present the first report on the design and manufacturing process of trousers excavated at Yanghai cemetery (42°48′–42°49′N, 89°39′–89°40′E) near the Turfan oasis, western China. In tombs M21 and M157 fragments of woollen trousers were discovered which have been radiocarbon dated to the time interval between the 13th and the 10th century BC. Their age corresponds to the spread of mobile pastoralism in eastern Central Asia and predates the widely known Scythian finds. Using methods of fashion design, the cut of both trousers was studied in detail. The trousers were made of three independently woven pieces of fabric, one nearly rectangular for each side spanning the whole length from waistband to hemline at the ankle and one stepped cross-shaped crotch-piece which bridged the gap between the two side-pieces. The tailoring process did not involve cutting the cloth: instead the parts were shaped on the loom, and they were shaped in the correct size to fit a specific person. The yarns of the three fabrics and threads for final sewing match in color and quality, which implies that the weaver and the tailor was the same person or that both cooperated in a highly coordinated way. The design of the trousers from Yanghai with straight-fitting legs and a wide crotch-piece seems to be a predecessor of modern riding trousers. Together with horse gear and weapons as grave goods in both tombs our results specify former assumptions that the invention of bifurcated lower body garments is related to the new epoch of horseback riding, mounted warfare and greater mobility. Trousers are essential part of the tool kit with which humans improve their physical qualities.
Read more at: http://phys.org/news/2014-06-year-trousers-chinese-grave-oldest.html#jCp


Scientists find stronger 3-D material that behaves like graphene

Scientists find stronger 3-D material that behaves like graphene
Scientists at Oxford, SLAC, Stanford and Berkeley Lab have discovered
 that a sturdy 3-D material, cadmium arsenide, mimics the 
electronic behavior of 2-D graphene. This illustration depicts fast-moving,
massless electrons inside the material. The discovery could lead to new 
and faster types of electronic devices. Credit: Greg Stewart/SLAC


Scientists have discovered a material that has the same extraordinary electronic properties as 2-D graphene, but in a sturdy 3-D form that should be much easier to shape into electronic devices such as very fast transistors, sensors and transparent electrodes.

The material, cadmium arsenide, is being explored independently by three groups, one of which includes researchers at the University of Oxford, SLAC, Stanford and Lawrence Berkeley National Laboratory who described their results in a paper published May 25 in Nature Materials.
"Now more and more people realize the potential in the science and technology of this particular material. This growing interest will promote rapid progress in the field – including the exploration of its use in functional devices and the search for similar materials," said Yulin Chen of the University of Oxford, who led the research.
The group's work builds on its earlier studies of a sodium bismuth compound that also mimics graphene but turns to powder when exposed to air. Both compounds had been predicted by co-authors Zhong Fang and Xi Dai, theoretical physicists from the Chinese Academy of Sciences, who suggested that cadmium arsenide, which is used in detectors and sensors, would provide the same properties in a much more stable form.
Their prediction proved correct, said Zhongkai Liu, the paper's first author and a graduate student at SIMES, the Stanford Institute for Materials and Energy Sciences at SLAC. "The environmental stability of cadmium arsenide allows us to explore it very systematically, and makes it easier to study," he said.
Graphene is a one-atom-thick sheet of carbon atoms peeled from a piece of graphite, which is familiar as the lead in pencils. One of its hallmarks is the weird behavior of its electrons: When confined to this thin layer of regularly spaced atoms, these lightweight particles act as if they have no mass at all. This allows them to zip through the material much faster than usual. The scientists who first isolated graphene in 2004 were awarded the Nobel Prize in Physics; and researchers have been racing to explore its properties and find practical uses for it ever since.
One such quest has been to find graphene-like materials that are three-dimensional, and thus much easier to craft into practical devices. Two other international collaborations based at Princeton University and in Dresden, Germany, have also been pursuing cadmium arsenide as a possibility. One published a paper on its results in the May 7 issue of Nature Communications, and the other has posted an unpublished paper on the preprint server arXiv.
Chen's group made samples of cadmium arsenide at Oxford and tested them at the Diamond Light Source in the United Kingdom and at Berkeley Lab's Advanced Light Source.
"We think this family of materials can be a good candidate for everyday use," Chen said, "and we're working with theorists to see if there are even better materials out there. In addition, we can use them as a platform to create and explore even more exotic states of matter; when you open a door, you find there are many other doors behind it."
The research team included Zhi-Xun Shen, a professor at SLAC and Stanford and SLAC's advisor for science and technology; Zahid Hussain, senior staff scientist at Berkeley Lab; and other researchers from SIMES, Berkeley Lab, Oxford University, Fudan University in Shanghai, the Chinese Academy of Sciences and Diamond Light Source. The work was partially funded by the U.S. Department of Energy Office of Science and the Defense Advanced Research Projects Agency (DARPA) Mesodynamic Architectures program.

http://phys.org/


Five or more blistering sunburns before age 20 may increase melanoma risk by 80 percent

Micrograph of malignant melanoma. Cytology specimen.
(Photo : Nephron/Wikipeida) Micrograph of malignant melanoma. Cytology specimen.

The risk of developing the most deadly form of skin cancer, melanoma, was more closely related to sun exposure in early life than in adulthood in young Caucasian women, according to a study published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
"Our results suggest that sun exposures in both early life and adulthood were predictive of nonmelanoma skin cancers, whereas melanoma risk was predominantly associated with sun exposure in early life in a cohort of young women," said Abrar A. Qureshi, M.D., MPH, professor and chair of the Department of Dermatology at Warren Alpert Medical School of the Brown University and Rhode Island Hospital in Providence.
After following 108,916 Caucasian registered nurses for about 20 years, this study found that those who had at least five blistering sunburns when they were 15 to 20 years old had a 68 percent increased risk for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin, and an 80 percent increased risk for melanoma. Those who were exposed to the highest amounts of cumulative ultraviolet (UV) radiation in adulthood had no increased risk for melanoma, but had a 2.35-fold and 2.53-fold increased risk for developing BCC and SCC of the skin.
"Pattern of sun exposure was not uniformly associated with the risk for all the three main skin cancers we see in the United States, suggesting that there are some differences in the pathophysiology of these skin cancers," said Qureshi. "An individual's risk of developing skin cancer depends on both host and environmental risk factors. Persons with high host-risk traits, such as red hair color, higher number of moles, and high sunburn susceptibility, should pay more attention to avoid excessive sun exposure, especially early in life."
Participants were from the Nurses' Health Study II. At the time of registration they were between the ages of 25 and 42 and resided in 14 different states. At registration, the participants responded to a baseline questionnaire about their medical histories and potential risk factors for skin cancers, including number of moles on legs, number of blistering sunburns between age 15 and 20, and family history of melanoma.
Updated health information was collected every two years for about 20 years. During this time, participants answered additional questions related to skin cancer risk, including updated family history, tanning bed use, smoking and alcohol consumption habits, and body mass index.
The researchers took into account the duration participants spent residing at different locations in the United States during follow-up to calculate the cumulative UV exposure for each individual, and then grouped the participants under three categories of UV exposure: low, medium, and high baseline annual UV flux.
About 24 percent of the participants had experienced painful blisters as a child or adolescent, about 10 percent had more than five blistering sunburns between ages 15 and 20, and about 24 percent had used tanning beds.
Of the study participants, 6,955 were diagnosed with BCC, 880 were diagnosed with SCC of the skin, and 779 were diagnosed with melanoma. Of those with melanoma, 445 had invasive cancer.
After adjusting for potential confounders, Qureshi and colleagues found a strong dose-response relationship between cumulative UV flux and risk for BCC and SCC of the skin, but no such association was seen for melanoma. Those who had at least five blistering sunburns between ages 15 and 20 had increased likelihood for developing any of the three types of skin cancers, but the greatest risk was for developing melanoma.
The researchers also found that the host-risk profile may alter an individual's risk for developing sun exposure-associated, nonmelanoma skin cancers.
"Parents may need to be advised to pay more attention to protection from early-life sun exposure for their kids in order to reduce the likelihood of developing melanoma as they grow up," said Qureshi. "Older individuals should also be cautious with their sun exposure, because cumulative sun exposure increases skin cancer risk as well."



World's best thermometer made from light

World’s best thermometer made from light
A computer generated image of the Light Thermometer. A slight difference in the
 speed of the green and red light can tell us the temperature. Credit: Dr James Anstie, 
IPAS and School of Chemistry and Physics, University of Adelaide.

    University of Adelaide physics researchers have produced the world's most sensitive thermometer – three times more precise than the best thermometers in existence.
Published in the journal Physical Review Letters, the researchers from the University's Institute for Photonics and Advanced Sensing (IPAS) report they have been able to measure temperature with a precision of 30 billionths of a degree.
"We believe this is the best measurement ever made of temperature − at room temperature," says project leader Professor Andre Luiten, Chair of Experimental Physics in IPAS and the School of Chemistry and Physics, pointing out that it is possible to make more sensitive measurements of temperature in cryogenic environments (at very low temperatures) near absolute zero.
"We've been able to measure temperature differences to 30 billionths of a degree in one second," says Professor Luiten.
"To emphasise how precise this is, when we examine the temperature of an object we find that it is always fluctuating. We all knew that if you looked closely enough you find that all the atoms in any material are always jiggling about, but we actually see this unceasing fluctuation with our thermometer, showing that the microscopic world is always in motion."
The paper – Nano-Kelvin Thermometry and Temperature Control: Beyond the Thermal Noise Limit – describes a new and very sensitive, but unorthodox, thermometer that uses light to measure temperature. PhD candidate Wenle Weng carried out the work.
The thermometer injects two colours of light (red and green) into a highly polished crystalline disk. The two colours travel at slightly different speeds in the crystal, depending on the temperature of the crystal.
"When we heat up the crystal we find that the red light slows down by a tiny amount with respect to the green light," Professor Luiten says.
"By forcing the light to circulate thousands of times around the edge of this disk in the same way that sound concentrates and reinforces itself in a curve in a phenomena known as a "whispering gallery" – as seen in St Paul's Cathedral in London or the Whispering Wall at Barossa Reservoir – then we can measure this minuscule difference in speed with great precision."
Professor Luiten says the researchers have developed a new technique which could be redesigned for ultra-sensitive measurements of other things such as pressure, humidity, force or searching for a particular chemical.
"Being able to measure many different aspects of our environment with such a high degree of precision, using instruments small enough to carry around, has the capacity to revolutionise technologies used for a variety of industrial and medical applications where detection of trace amounts has great importance," Professor Luiten says.
http://phys.org/


Tractor beam that can move objects


A TRACTOR beam familiar from sci-fi classics such 
as Star Wars and Star Trek, has become fact not fiction

Physicists at Dundee University have created a functioning acoustic ­tractor beam, using energy from an ultrasound array to exert force behind an object and pull it to the energy source.
"This is the first time anyone has demonstrated a working acoustic tractor beam and the first time such a beam has been used to move anything bigger than microscopic targets," said Dr Christine Demore, of the Institute for Medical Science and Technology at Dundee.
"We were able to show that you could exert sufficient force on an object around one centimetre in size to hold or move it, by directing twin beams of energy from the ultrasound array towards the back of the object."
The team used an ultrasound device that is already clinically approved for use in MRI-guided focused ultrasound surgery.
The Dundee researchers previously demonstrated that Dr Who's sonic screwdriver could be created using a similar ultrasound array.