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Science & Technology News.
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The weakness of gravity
The weakness of gravity | Sci-tech | DAWN.COM
The story goes that a young Newton was sitting beneath a tree when an apple fell to the ground, which he famously attributed to a force of attraction between the apple and the Earth called gravity. He went one step further to suggest that it is the same force that is responsible for the orbits of the moon around the Earth and the Earth around the Sun.
Whereas the story is most likely fictional, it illustrates an important concept that ideas are borne out of curiosity. Learning to ask the right questions is one of the cornerstones of scientific advancement. The lack thereof, I believe, has played a fundamental role in scientific decline in the Muslim world (as Ive previously discussed here).
One of such questions and indeed one of the biggest unsolved mysteries in our understanding of the Universe is; why is gravity so much weaker than the other forces of nature? It is questions like this that the Large Hadron Collider, the most powerful particle accelerator in the world, is designed to solve. This particular curiosity is also one of my primary research preoccupations and the reason for my somewhat long hiatus from the blogosphere.
Our current understanding of the Universe is embodied in a theoretical framework called the Standard Model. The theory describes the fundamental particles and their interactions with each other via four forces, the weakest of which is gravity. The weakness of gravity may come as a surprise since we hold gravity responsible for the Moon orbiting around the Earth, the Earth around the Sun, the motion of the galaxies and the fact that were not floating in space. However, it is actually extraordinarily weak compared to the other forces in nature.
How weak is gravity? It takes the entire mass of the Earth to pull that apple to the ground! The force of gravity becomes stronger the more mass objects have and the closer they are to each other. Its effects only become visible when we talk about objects as large as the Earth and are virtually unnoticeable if you consider for instance, the gravitational attraction between the individual apples on the tree.
So, what makes gravity so much weaker than all the other forces?
In 1998, Nima Arkani-Hamed, Savas Dimopoulos and Gia Dvali proposed the scenario of Large Extra Dimensions to solve this puzzle. The basic idea is that there are more dimensions in space than the three-dimensions that we live in and experience.
How does this explain why gravity is so weak? While the other forces of nature are constrained to our three-dimensional world, gravity is thought to be free to propagate in these extra dimensions, so its effect in our three-dimensional world is somewhat diluted. Hence we see it as being weak since it is thinly spread over all the dimensions, whereas its strength is probably comparable to the other forces.
It is proposed that these extra dimensions are un-observably small, since we dont witness objects vanishing into these higher dimensions and that they are compactified, for instance they may be tightly curled in a loop, such that even if you enter one of these dimensions, you wont get very far and end up right where you started.
At the Large Hadron Collider experiment at CERN, often referred to as the Big Bang machine, we accelerate bunches of protons in opposite directions around a 27 km ring and then collide them head-on. The collision produces an immense amount of energy that can create new particles. One of these could be the graviton, the particle thought to be responsible for transmitting the gravitational force. If gravity permeates through all of the extra dimensions, there may be times when graviton is produced in these high energy collisions and then escapes immediately into these other dimensions.
This disappearing act of the graviton would therefore be a tell-tale sign of the existence of extra dimensions and would produce an imbalance of energy in our detectors as the energy of the graviton would be missing.
We searched through scores of proton-proton collisions to find cases where a graviton may have been produced and then vanished immediately into these higher dimensions. So far, with the data available at the end of 2010, we have not found any evidence for these particles and as a result we were able to place constraints on the size and the number of these extra dimensions.
However, so far in 2011 we have accumulated 30 times more data than was available in 2010. With so many proton-proton collisions at the highest energies ever achieved, the likelihood of a scientific breakthrough has increased tremendously. Who knows what we may discover and what Pandoras Box it might open. The beauty of science is that there will always be one more question to answer.
-Sarah Alam Malik
Sarah Alam Malik
The weakness of gravity | Sci-tech | DAWN.COM
The story goes that a young Newton was sitting beneath a tree when an apple fell to the ground, which he famously attributed to a force of attraction between the apple and the Earth called gravity. He went one step further to suggest that it is the same force that is responsible for the orbits of the moon around the Earth and the Earth around the Sun.
Whereas the story is most likely fictional, it illustrates an important concept that ideas are borne out of curiosity. Learning to ask the right questions is one of the cornerstones of scientific advancement. The lack thereof, I believe, has played a fundamental role in scientific decline in the Muslim world (as Ive previously discussed here).
One of such questions and indeed one of the biggest unsolved mysteries in our understanding of the Universe is; why is gravity so much weaker than the other forces of nature? It is questions like this that the Large Hadron Collider, the most powerful particle accelerator in the world, is designed to solve. This particular curiosity is also one of my primary research preoccupations and the reason for my somewhat long hiatus from the blogosphere.
Our current understanding of the Universe is embodied in a theoretical framework called the Standard Model. The theory describes the fundamental particles and their interactions with each other via four forces, the weakest of which is gravity. The weakness of gravity may come as a surprise since we hold gravity responsible for the Moon orbiting around the Earth, the Earth around the Sun, the motion of the galaxies and the fact that were not floating in space. However, it is actually extraordinarily weak compared to the other forces in nature.
How weak is gravity? It takes the entire mass of the Earth to pull that apple to the ground! The force of gravity becomes stronger the more mass objects have and the closer they are to each other. Its effects only become visible when we talk about objects as large as the Earth and are virtually unnoticeable if you consider for instance, the gravitational attraction between the individual apples on the tree.
So, what makes gravity so much weaker than all the other forces?
In 1998, Nima Arkani-Hamed, Savas Dimopoulos and Gia Dvali proposed the scenario of Large Extra Dimensions to solve this puzzle. The basic idea is that there are more dimensions in space than the three-dimensions that we live in and experience.
How does this explain why gravity is so weak? While the other forces of nature are constrained to our three-dimensional world, gravity is thought to be free to propagate in these extra dimensions, so its effect in our three-dimensional world is somewhat diluted. Hence we see it as being weak since it is thinly spread over all the dimensions, whereas its strength is probably comparable to the other forces.
It is proposed that these extra dimensions are un-observably small, since we dont witness objects vanishing into these higher dimensions and that they are compactified, for instance they may be tightly curled in a loop, such that even if you enter one of these dimensions, you wont get very far and end up right where you started.
At the Large Hadron Collider experiment at CERN, often referred to as the Big Bang machine, we accelerate bunches of protons in opposite directions around a 27 km ring and then collide them head-on. The collision produces an immense amount of energy that can create new particles. One of these could be the graviton, the particle thought to be responsible for transmitting the gravitational force. If gravity permeates through all of the extra dimensions, there may be times when graviton is produced in these high energy collisions and then escapes immediately into these other dimensions.
This disappearing act of the graviton would therefore be a tell-tale sign of the existence of extra dimensions and would produce an imbalance of energy in our detectors as the energy of the graviton would be missing.
We searched through scores of proton-proton collisions to find cases where a graviton may have been produced and then vanished immediately into these higher dimensions. So far, with the data available at the end of 2010, we have not found any evidence for these particles and as a result we were able to place constraints on the size and the number of these extra dimensions.
However, so far in 2011 we have accumulated 30 times more data than was available in 2010. With so many proton-proton collisions at the highest energies ever achieved, the likelihood of a scientific breakthrough has increased tremendously. Who knows what we may discover and what Pandoras Box it might open. The beauty of science is that there will always be one more question to answer.
-Sarah Alam Malik
Sarah Alam Malik
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China has made its first supercomputer based on Chinese microprocessor chips, an advance that surprised high-performance U.S. computing specialists.
The announcement was made this week at a technical meeting held in Jinan, China, organised by industry and government organisations. The new machine, the Sunway BlueLight MPP, was installed in September at the National Supercomputer Center in Jinan, the capital of Shandong province in eastern China.
The Sunway system, which can perform about 1,000 trillion calculations per second a petaflop will probably rank among the 20 fastest computers in the world. More significantly, it is composed of 8,700 ShenWei SW1600 microprocessors, designed at a Chinese computer institute and manufactured in Shanghai.
Currently, the Chinese are about three generations behind the state-of-art chip making technologies used by world leaders such as the United States, South Korea, Japan and Taiwan.
“This is a bit of a surprise,” said Jack Dongarra, a computer scientist at the University of Tennessee and a leader of the Top500 project, a list of the world's fastest computers.
Last fall, another Chinese based supercomputer, the Tianhe-1A, created an international sensation when it was briefly ranked as the world's fastest, before it was displaced in the spring by a rival Japanese machine, the K Computer, designed by Fujitsu.
INTERNAL SYSTEM
But the Tianhe was built from processor chips made by U.S. companies, Intel and Nvidia, though its internal switching system was designed by Chinese computer engineers. Similarly, the K computer was based on Sparc chips, originally designed at Sun Microsystems in Silicon Valley.
Mr. Dongarra said the Sunway's theoretical peak performance was about 74 per cent as fast as the fastest U.S. computer the Jaguar supercomputer at the Department of Energy facility at Oak Ridge National Laboratory, made by Cray Inc. That machine is currently the third fastest on the list.
The Energy Department is planning three supercomputers that would run at 10 to 20 petaflops. And the United States is embarking on an effort to reach an exaflop, or 1 million trillion mathematical operations in a second, sometime before the end of the decade, although most computer scientists say the necessary technologies do not yet exist.
DESIGN PRINCIPLES
To build such a computer from existing components would require immense amounts of electricity roughly the amount produced by a medium-sized nuclear power plant.
In contrast, Mr. Dongarra said it was intriguing that the power requirements of the new Chinese supercomputer were relatively modest about 1 megawatt, according to reports from the technical conference. The Tianhe supercomputer consumes about 4 megawatts and the Jaguar about 7.
The ShenWei microprocessor appears to be based on some of the same design principles that are favoured by Intel's most advanced microprocessors, according to several supercomputer experts in the United States.
But there is disagreement over whether the machine's cooling technology is appropriate for designs that will be required by the exaflop-class supercomputers of the future.
Photos of the new Sunway supercomputer reveal an elaborate water-cooling system that may be a significant advance in the design of the very fastest machines.
“Getting this cooling technology correct is very, very difficult,” said Steven Wallach, chief scientist at Convey Computer, a supercomputer firm based in Richardson, Texas.
“This tells me that this is a serious design. This cooling technology could scale to exaflop. They are in the hunt to win.” — New York Times News Service
Source: The Hindu : News / International : China's supercomputer surprises U.S. experts
And China races ahead!
The announcement was made this week at a technical meeting held in Jinan, China, organised by industry and government organisations. The new machine, the Sunway BlueLight MPP, was installed in September at the National Supercomputer Center in Jinan, the capital of Shandong province in eastern China.
The Sunway system, which can perform about 1,000 trillion calculations per second a petaflop will probably rank among the 20 fastest computers in the world. More significantly, it is composed of 8,700 ShenWei SW1600 microprocessors, designed at a Chinese computer institute and manufactured in Shanghai.
Currently, the Chinese are about three generations behind the state-of-art chip making technologies used by world leaders such as the United States, South Korea, Japan and Taiwan.
“This is a bit of a surprise,” said Jack Dongarra, a computer scientist at the University of Tennessee and a leader of the Top500 project, a list of the world's fastest computers.
Last fall, another Chinese based supercomputer, the Tianhe-1A, created an international sensation when it was briefly ranked as the world's fastest, before it was displaced in the spring by a rival Japanese machine, the K Computer, designed by Fujitsu.
INTERNAL SYSTEM
But the Tianhe was built from processor chips made by U.S. companies, Intel and Nvidia, though its internal switching system was designed by Chinese computer engineers. Similarly, the K computer was based on Sparc chips, originally designed at Sun Microsystems in Silicon Valley.
Mr. Dongarra said the Sunway's theoretical peak performance was about 74 per cent as fast as the fastest U.S. computer the Jaguar supercomputer at the Department of Energy facility at Oak Ridge National Laboratory, made by Cray Inc. That machine is currently the third fastest on the list.
The Energy Department is planning three supercomputers that would run at 10 to 20 petaflops. And the United States is embarking on an effort to reach an exaflop, or 1 million trillion mathematical operations in a second, sometime before the end of the decade, although most computer scientists say the necessary technologies do not yet exist.
DESIGN PRINCIPLES
To build such a computer from existing components would require immense amounts of electricity roughly the amount produced by a medium-sized nuclear power plant.
In contrast, Mr. Dongarra said it was intriguing that the power requirements of the new Chinese supercomputer were relatively modest about 1 megawatt, according to reports from the technical conference. The Tianhe supercomputer consumes about 4 megawatts and the Jaguar about 7.
The ShenWei microprocessor appears to be based on some of the same design principles that are favoured by Intel's most advanced microprocessors, according to several supercomputer experts in the United States.
But there is disagreement over whether the machine's cooling technology is appropriate for designs that will be required by the exaflop-class supercomputers of the future.
Photos of the new Sunway supercomputer reveal an elaborate water-cooling system that may be a significant advance in the design of the very fastest machines.
“Getting this cooling technology correct is very, very difficult,” said Steven Wallach, chief scientist at Convey Computer, a supercomputer firm based in Richardson, Texas.
“This tells me that this is a serious design. This cooling technology could scale to exaflop. They are in the hunt to win.” — New York Times News Service
Source: The Hindu : News / International : China's supercomputer surprises U.S. experts
And China races ahead!
Audio
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Big Dog robot video (old)-skip to 0:35 for a really impressive show of stabilization.
Completed seismic protection system for the Tokamak reactor, filmed in early February.
Reactor cut-out.
Completed seismic protection system for the Tokamak reactor, filmed in early February.
Reactor cut-out.
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Dubious
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Yup, I had watched a documentary from Indonesia (some years back) where the study or observations were conducted in the city area where chimps got their food from tourists and crossed roads. One baby came under a car and the mother carried the baby for a few days or something...it was the saddest thing to watch!!
The SC
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Scientists Create 'Rubber-Band Electronics'
TEHRAN (FNA)- For people with heart conditions and other ailments that require monitoring, life can be complicated by constant hospital visits and time-consuming tests. But what if much of the testing done at hospitals could be conducted in the patient's home, office, or car?
Scientists foresee a time when medical monitoring devices are integrated seamlessly into the human body, able to track a patient's vital signs and transmit them to his doctors. But one major obstacle continues to hinder technologies like these: electronics are too rigid.
Researchers at the McCormick School of Engineering, working with a team of scientists from the United States and abroad, have recently developed a design that allows electronics to bend and stretch to more than 200 percent their original size, four times greater than is possible with today's technology. The key is a combination of a porous polymer and liquid metal.
A paper about the findings, "Three-dimensional Nanonetworks for Giant Stretchability in Dielectrics and Conductors," was published June 26 in the journal Nature Communications.
"With current technology, electronics are able to stretch a small amount, but many potential applications require a device to stretch like a rubber band," said Yonggang Huang, Joseph Cummings Professor of Civil and Environmental Engineering and Mechanical Engineering, who conducted the research with partners at the Korea Advanced Institute of Science and Technology (South Korea), Dalian University of Technology (China), and the University of Illinois at Urbana-Champaign. "With that level of stretchability we could see medical devices integrated into the human body."
In the past five years, Huang and collaborators at the University of Illinois have developed electronics with about 50 percent stretchability, but this is not high enough for many applications.
One challenge facing these researchers has been overcoming a loss of conductivity in stretchable electronics. Circuits made from solid metals that are on the market today can survive a small amount of stretch, but their electrical conductivity plummets by 100 times when stretched. "This conductivity loss really defeats the point of stretchable electronics," Huang said.
Huang's team has found a way to overcome these challenges. First, they created a highly porous three-dimensional structure using a polymer material, poly(dimethylsiloxane) (PDMS), that can stretch to three times its original size. Then they placed a liquid metal (EGaIn) inside the pores, allowing electricity to flow consistently even when the material is excessively stretched.
The result is a material that is both highly stretchable and extremely conductive.
"By combining a liquid metal in a porous polymer, we achieved 200 percent stretchability in a material that does not suffer from stretch," Huang said. "Once you achieve that technology, any electronic can behave like a rubber band."
TEHRAN (FNA)- For people with heart conditions and other ailments that require monitoring, life can be complicated by constant hospital visits and time-consuming tests. But what if much of the testing done at hospitals could be conducted in the patient's home, office, or car?
Scientists foresee a time when medical monitoring devices are integrated seamlessly into the human body, able to track a patient's vital signs and transmit them to his doctors. But one major obstacle continues to hinder technologies like these: electronics are too rigid.
Researchers at the McCormick School of Engineering, working with a team of scientists from the United States and abroad, have recently developed a design that allows electronics to bend and stretch to more than 200 percent their original size, four times greater than is possible with today's technology. The key is a combination of a porous polymer and liquid metal.
A paper about the findings, "Three-dimensional Nanonetworks for Giant Stretchability in Dielectrics and Conductors," was published June 26 in the journal Nature Communications.
"With current technology, electronics are able to stretch a small amount, but many potential applications require a device to stretch like a rubber band," said Yonggang Huang, Joseph Cummings Professor of Civil and Environmental Engineering and Mechanical Engineering, who conducted the research with partners at the Korea Advanced Institute of Science and Technology (South Korea), Dalian University of Technology (China), and the University of Illinois at Urbana-Champaign. "With that level of stretchability we could see medical devices integrated into the human body."
In the past five years, Huang and collaborators at the University of Illinois have developed electronics with about 50 percent stretchability, but this is not high enough for many applications.
One challenge facing these researchers has been overcoming a loss of conductivity in stretchable electronics. Circuits made from solid metals that are on the market today can survive a small amount of stretch, but their electrical conductivity plummets by 100 times when stretched. "This conductivity loss really defeats the point of stretchable electronics," Huang said.
Huang's team has found a way to overcome these challenges. First, they created a highly porous three-dimensional structure using a polymer material, poly(dimethylsiloxane) (PDMS), that can stretch to three times its original size. Then they placed a liquid metal (EGaIn) inside the pores, allowing electricity to flow consistently even when the material is excessively stretched.
The result is a material that is both highly stretchable and extremely conductive.
"By combining a liquid metal in a porous polymer, we achieved 200 percent stretchability in a material that does not suffer from stretch," Huang said. "Once you achieve that technology, any electronic can behave like a rubber band."
The SC
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The weakness of gravity
The weakness of gravity | Sci-tech | DAWN.COM
The story goes that a young Newton was sitting beneath a tree when an apple fell to the ground, which he famously attributed to a force of attraction between the apple and the Earth called gravity. He went one step further to suggest that it is the same force that is responsible for the orbits of the moon around the Earth and the Earth around the Sun.
Whereas the story is most likely fictional, it illustrates an important concept that ideas are borne out of curiosity. Learning to ask the right questions is one of the cornerstones of scientific advancement. The lack thereof, I believe, has played a fundamental role in scientific decline in the Muslim world (as I’ve previously discussed here).
One of such questions and indeed one of the biggest unsolved mysteries in our understanding of the Universe is; why is gravity so much weaker than the other forces of nature? It is questions like this that the Large Hadron Collider, the most powerful particle accelerator in the world, is designed to solve. This particular curiosity is also one of my primary research preoccupations and the reason for my somewhat long hiatus from the blogosphere.
Our current understanding of the Universe is embodied in a theoretical framework called the Standard Model. The theory describes the fundamental particles and their interactions with each other via four forces, the weakest of which is gravity. The weakness of gravity may come as a surprise since we hold gravity responsible for the Moon orbiting around the Earth, the Earth around the Sun, the motion of the galaxies and the fact that we’re not floating in space. However, it is actually extraordinarily weak compared to the other forces in nature.
How weak is gravity? It takes the entire mass of the Earth to pull that apple to the ground! The force of gravity becomes stronger the more mass objects have and the closer they are to each other. Its effects only become visible when we talk about objects as large as the Earth and are virtually unnoticeable if you consider for instance, the gravitational attraction between the individual apples on the tree.
So, what makes gravity so much weaker than all the other forces?
In 1998, Nima Arkani-Hamed, Savas Dimopoulos and Gia Dvali proposed the scenario of Large Extra Dimensions to solve this puzzle. The basic idea is that there are more dimensions in space than the three-dimensions that we live in and experience.
How does this explain why gravity is so weak? While the other forces of nature are constrained to our three-dimensional world, gravity is thought to be free to propagate in these extra dimensions, so its effect in our three-dimensional world is somewhat diluted. Hence we see it as being weak since it is thinly spread over all the dimensions, whereas its strength is probably comparable to the other forces.
It is proposed that these extra dimensions are un-observably small, since we don’t witness objects vanishing into these higher dimensions and that they are compactified, for instance they may be tightly curled in a loop, such that even if you enter one of these dimensions, you won’t get very far and end up right where you started.
At the Large Hadron Collider experiment at CERN, often referred to as the ‘Big Bang machine’, we accelerate bunches of protons in opposite directions around a 27 km ring and then collide them head-on. The collision produces an immense amount of energy that can create new particles. One of these could be the graviton, the particle thought to be responsible for transmitting the gravitational force. If gravity permeates through all of the extra dimensions, there may be times when graviton is produced in these high energy collisions and then escapes immediately into these other dimensions.
This disappearing act of the graviton would therefore be a tell-tale sign of the existence of extra dimensions and would produce an imbalance of energy in our detectors as the energy of the graviton would be ‘missing’.
We searched through scores of proton-proton collisions to find cases where a graviton may have been produced and then vanished immediately into these higher dimensions. So far, with the data available at the end of 2010, we have not found any evidence for these particles and as a result we were able to place constraints on the size and the number of these extra dimensions.
However, so far in 2011 we have accumulated 30 times more data than was available in 2010. With so many proton-proton collisions at the highest energies ever achieved, the likelihood of a scientific breakthrough has increased tremendously. Who knows what we may discover and what Pandora’s Box it might open. The beauty of science is that there will always be one more question to answer.
-Sarah Alam Malik
Sarah Alam Malik
If Gravity is weak and the galaxies are held by this force that is beyond our imagination, can we really speculate on the other 3 forces, be it in the microcosm or the macrocosm?
The problem is that the deeper you go the same things you will find, the best example is the Mandelbrot set.
The other problem is that humans are limited in all their 5 senses to begin with, and to go beyond those limits is the main challenge, since the machines used to measure things in the universe are man made, they are obviously at the limit of its senses; even imagination is limited to the amount of the information the brain or even brains can gather and input into supercomputers.
And I am not even talking about the effect of gravity on human beings themselves - being subject to it and wanting to observe and investigate it !!! -, plus the effects of the other forces.
A potent observer should be out of all these forces to see the truth, like this " GOD particle " or "Higgs Boson" these out of their minds scientists are falsely claiming they have or being on the verge of discovering ; the experiment was a failure.; a lot of applause for the effort but nothing to show off, even the variations they have noticed were found to be related to electrical malfunctions in CERN's Large Hadron Collider !!!
Neutrinos ARE the "particles" permeating all matter.
According to "Big Bang" theory, neutrinos, as noted, may permeate the universe almost to the extent of photons, and thus may be among the most common particles.
One reason that neutrinos supposedly fill all corners of the universe is because of their high speed. Neutrinos have supposedly travelled at light speed (and thus been "relativistic" according to quantum theory) till very recently. Many neutrinos today thus formed at the birth of the universe. Others are produced in the interiors of stars. Recent research (CERN, June 8th, 2012) suggests that neutrinos today may travel at near light speed but not faster.
http://suite101.com/article/elusive-neutrinos-clues-to-the-universe-a408499
The SC
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The CERN physicists did not see this new particle directly, because it disintegrates too quickly. Rather, they divined its existence from sifting through the debris of millions of high-energy subatomic collisions and then searching for clues that the Higgs had been there. It's like divining the presence of an elusive snow leopard by studying thousands of criss-crossed paw prints.
http://www.pressherald.com/news/tiny-particle-seen-as-key-to-universe-discovered_2012-07-05.html
-------------------------------------------------------------------------------------------------------
In a study in the April 19 issue of the journal Nature (published online today), the IceCube collaboration says that a search for neutrinos emitted from 300 gamma ray bursts, unexpectedly found none! Because neutrinos are believed to accompany cosmic ray production, this result contradicts 15 years of predictions and challenges one of the two leading theories for the origin of the highest energy cosmic rays.
The result of this neutrino search is significant because for the first time we have an instrument with sufficient sensitivity to open a new window on cosmic ray production and the interior processes of GRBs [gamma ray bursts]," said IceCube spokesperson and University of Maryland physics professor Greg Sullivan. The unexpected absence of neutrinos from GRBs has forced a re-evaluation of the theory for production of cosmic rays and neutrinos in a GRB fireball and possibly the theory that high energy cosmic rays are generated in fireballs."
Cosmic rays are electrically charged particles, such as protons, that strike Earth from all directions, with energies up to one hundred million times higher than those created in man-made accelerators. The intense conditions needed to generate such energetic particles have focused physicists' interest on two potential sources: the massive black holes at the centers of active galaxies, and the exploding fireballs observed by astronomers as gamma ray bursts (GRBs).
http://newsdesk.umd.edu/uniini/release.cfm?ArticleID=2672
http://www.pressherald.com/news/tiny-particle-seen-as-key-to-universe-discovered_2012-07-05.html
-------------------------------------------------------------------------------------------------------
In a study in the April 19 issue of the journal Nature (published online today), the IceCube collaboration says that a search for neutrinos emitted from 300 gamma ray bursts, unexpectedly found none! Because neutrinos are believed to accompany cosmic ray production, this result contradicts 15 years of predictions and challenges one of the two leading theories for the origin of the highest energy cosmic rays.
The result of this neutrino search is significant because for the first time we have an instrument with sufficient sensitivity to open a new window on cosmic ray production and the interior processes of GRBs [gamma ray bursts]," said IceCube spokesperson and University of Maryland physics professor Greg Sullivan. The unexpected absence of neutrinos from GRBs has forced a re-evaluation of the theory for production of cosmic rays and neutrinos in a GRB fireball and possibly the theory that high energy cosmic rays are generated in fireballs."
Cosmic rays are electrically charged particles, such as protons, that strike Earth from all directions, with energies up to one hundred million times higher than those created in man-made accelerators. The intense conditions needed to generate such energetic particles have focused physicists' interest on two potential sources: the massive black holes at the centers of active galaxies, and the exploding fireballs observed by astronomers as gamma ray bursts (GRBs).
http://newsdesk.umd.edu/uniini/release.cfm?ArticleID=2672
Al Bhatti
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August 21st, 2012
Star Wars-style speeder bike could be suitable for heavy-lift
Californian company Aerofex’ hover vehicle may look like a speeder bike from Star Wars but its real-world applications include heavy-left utilisation, according to one of its founders.
Mark De Roche, an aerospace engineer by training, told InnovationNewsDaily, that the prototype hover vehicle could eventually carry out heavy lift duties on rough terrain.
He said: “Think of it as lowering the threshold of flight, down to the domain of ATV’s (all-terrain vehicles).”
The Aerofex uses enclosed, ducted tandem rotor blades. Original designs for such vehicles date back to the 1960s but Aerofex believes it has solved problems regarding roll-over and stability which have prevented the technology progressing in the intervening decades.
The Aerofex bike solves a five-decade problem of controlling ducted rotors
-------
The Aerofex bike in action.
Star Wars-style speeder bike could be suitable for heavy-lift
Californian company Aerofex’ hover vehicle may look like a speeder bike from Star Wars but its real-world applications include heavy-left utilisation, according to one of its founders.
Mark De Roche, an aerospace engineer by training, told InnovationNewsDaily, that the prototype hover vehicle could eventually carry out heavy lift duties on rough terrain.
He said: “Think of it as lowering the threshold of flight, down to the domain of ATV’s (all-terrain vehicles).”
The Aerofex uses enclosed, ducted tandem rotor blades. Original designs for such vehicles date back to the 1960s but Aerofex believes it has solved problems regarding roll-over and stability which have prevented the technology progressing in the intervening decades.
The Aerofex bike solves a five-decade problem of controlling ducted rotors
-------
The Aerofex bike in action.
Last edited by a moderator:
Dubious
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Nothing new in Science?
Wonder if anyone is conducting molecular research in either cereals in Pakistan or fruits like grapes, berries...Would like to do some collaboration...I find people from every other corner of the world coming in my institute BUT PAKISTANIS...There was only 1 so far and I am the 2nd (in lets say 3-4 years can't find anyone who can tell me anything older than that!)
Wonder if anyone is conducting molecular research in either cereals in Pakistan or fruits like grapes, berries...Would like to do some collaboration...I find people from every other corner of the world coming in my institute BUT PAKISTANIS...There was only 1 so far and I am the 2nd (in lets say 3-4 years can't find anyone who can tell me anything older than that!)
Dubious
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I am not sure where to post this question:
Well, as a researcher I download loads of articles and sometimes I remember the context but not which paper...I recall 1 of my friend had a software where he had all his articles and he could search based on title of paper, author or words! For the life of me I can not remember the software, I got Mendeley desktop now...but I liked what my friend had....
Anyone knows of such a software?
Well, as a researcher I download loads of articles and sometimes I remember the context but not which paper...I recall 1 of my friend had a software where he had all his articles and he could search based on title of paper, author or words! For the life of me I can not remember the software, I got Mendeley desktop now...but I liked what my friend had....
Anyone knows of such a software?
Hyperion
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No idea, never used a PC. Why not use MBP@Apple. It's so easy, just command+F and you're done.
Blasphemy: So many people will come and bash me now for preaching @Apple ...
@Audio, you're really into robotics!
Mech or Electronics Engineer?
Dubious
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No idea, never used a PC. Why not use MBP@Apple. It's so easy, just command+F and you're done.
Blasphemy: So many people will come and bash me now for preaching @Apple ...
I was looking into article or word mining...sort of organizing my articles, managing them in folders and when I am done with that looking for words which are in my head but I can't remember which nerd wrote about it...Because I need to do referencing for a paper I would be writing in a few months...HEADACHE!
Apple is too costly and some softwares do not work with it! I just love softwares to play with genes and mapping populations...
Skies
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