April 17, 2006 One of the more visually arresting wearables on display at the recent CTIA Fashion in Motion shows was this vertebral wireless interface to be worn around the head and neck. A distinct possibility for a sci-fi horror movie role, the vertebral form of the Synapse concept came to University of University of Bridgeport student David Salonen in a dream, and has created such interest that he is interested in discussing options on how to bring the idea to market. “It’s completely free from buttons, plugs, wires and doohickies,” says David, “and an ideal way to stand out from the masses of umbilically-connected techno babies."
The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes". Light is composed of photons so we could ask if the photon has mass. The answer is then definitely "no": The photon is a massless particle. According to theory it has energy and momentum but no mass and this is confirmed by experiment to within strict limits. Even before it was known that light is composed of photons it was known that light carries momentum and will exert a pressure on a surface. This is not evidence that it has mass since momentum can exist without mass. [ For details see the Physics FAQ article What is the mass of the photon? ]. Sometimes people like to say that the photon does have mass because a photon has energy E = hf where h is Planck's constant and f is the frequency of the photon. Energy, they say, is equivalent to mass according to Einstein's famous formula E = m...
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