'IBM has announced that they are gearing up to build the world's fastest supercomputer, more than four times faster than the reigning champ, IBM's BlueGene/L. Nicknamed 'Roadrunner,' the new machine will be a hybrid of off-the-shelf CPUs and Cell chips designed for the PS3. Roadrunner is to be installed at Los Alamos National Laboratory, occupying 1,100 square metres of floorspace (that's a square about 110 feet on a side). According to the BBC: 'The computer will contain 16,000 standard processors working alongside 16,000 Cell processors... each Cell is capable of 256 billion calculations per second.''
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
Comments