The paper "Living in a Void: Testing the Copernican Principle with Distant Supernovae" by Timothy Clifton, Pedro G. Ferreira, Kate Land, argues that if we are living in a giant void - that is, if our cosmic neighbourhood is significantly less dense than other parts of the universe, then that could account for the fact that the universe's expansion appears to be accelerating.
As the New Scienist notes, "In fact, if the void were big enough - roughly the size of our observable universe - it might account for the supernovae observations that imply acceleration, and do away with the need for dark energy."
Source: http://lanl.arxiv.org/abs/0807.1443
Sunday, 20 July 2008
Thursday, 19 June 2008
Nanotube Radio
"We have constructed a fully functional, fully integrated radio receiver, orders-of-magnitude smaller than any previous radio, from a single carbon nanotube. The single nanotube serves, at once, as all major components of a radio: antenna, tuner, amplifier, and demodulator."Moreover, the antenna and tuner are implemented in a radically different manner than traditional radios, receiving signals via high frequency mechanical vibrations of the nanotube rather than through traditional electrical means."
Source: http://www.physics.berkeley.edu/research/zettl/projects/nanoradio/radio.html
Source: http://www.physics.berkeley.edu/research/zettl/projects/nanoradio/radio.html
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