“Nanotubes assemblies of various types are black and highly conductive,” said Dr. Mikhail Kozlov, a research scientist and the study’s lead author. “Their dark, conductive surface can be effectively heated with laser light or electricity to induce variations in the pressure of the air around the nanotubes — which we perceive as sound. It’s called the photo- or thermo-acoustic effect, and it’s the same principle Alexander Graham Bell used to produce sound on the first telephone.”
With laser excitation, no electrical contact with the nanotube speaker is required, making the speakers wireless.
“Speakers made with carbon nanotube sheets are extremely thin, light and almost transparent,” Kozlov said. “They have no moving parts and can be attached to any surface, which makes the surface acoustically active. They can be concealed in television and computer screens, apartment walls, or in the windows of buildings and cars. The almost invisible strands form films that can ‘talk.’”
In addition to filling a room with sound from invisible speakers, nanotube speakers could easily cancel sound from the noisiest neighbor or dim the roar of traffic rushing past a neighborhood, using the same principles as current sound-canceling technologies.
“The sound generation by nanotube sheets can help to achieve this effect on very large scales,” Kozlov said.
thinkahol * on 19 Oct 11Brain, bodily awareness, and the emergence of a conscious self: these entities and their relations are explored by Germanphilosopher and cognitive scientist Metzinger. Extensively working with neuroscientists he has come to the conclusion that, in fact, there is no such thing as a "self" -- that a "self" is simply the content of a model created by our brain - part of a virtual reality we create for ourselves. But if the self is not "real," he asks, why and how did it evolve? How does the brain construct the self? In a series of fascinating virtual reality experiments, Metzinger and his colleagues have attempted to create so-called "out-of-body experiences" in the lab, in order to explore these questions. As a philosopher, he offers a discussion of many of the latest results in robotics, neuroscience, dream and meditation research, and argues that the brain is much more powerful than we have ever imagined. He shows us, for example, that we now have the first machines that have developed an inner image of their own body -- and actually use this model to create intelligent behavior. In addition, studies exploring the connections between phantom limbs and the brain have shown us that even people born without arms or legs sometimes experience a sensation that they do in fact have limbs that are not there. Experiments like the "rubber-hand illusion" demonstrate how we can experience a fake hand as part of our self and even feel a sensation of touch on the phantom hand form the basis and testing ground for the idea that what we have called the "self" in the past is just the content of a transparent self-model in our brains. Now, as new ways of manipulating the conscious mind-brain appear on the scene, it will soon become possible to alter our subjective reality in an unprecedented manner. The cultural consequences of this, Metzinger claims, may be immense: we will need a new approach to ethics, and we will be forced to think about ourselves in a fundamentally new way. At
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