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20,000 Zombie PCs -- $3000

PhysicsExpert Re:Whose fault? (423 comments)

http://www.nd.edu/~jsmith30/xul/test/spoof.html

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Faster than light communication

PhysicsExpert PhysicsExpert writes  |  more than 11 years ago

Hello everybody

As you well know, here in the lab we are doing some interesting research to push back the boundaries of physics and inventing devices which will improve the world for all mankind. Our latest results are focused on speedy information transfer, which should pave the way for improved communication with deep space probes. Read on to learn more.

Now most people think that modern communication is pretty speedy: you can phone somebody on the opposite side of the world pretty much instantaneously for example, but in fact the speed at which information can be transferred is limited by the speed of light. This doesn't cause many problems while we're on earth, but once you start sending things into space the distances become much larger and the latency more of a problem. The communication lag between Earth and Mars is eight minutes for example, which is a big challenge for engineers wanting to control a robot on the planet's surface. Surely there has to be a better way.

Well, as with so much in life, modern physics has the answer. We in the lab propose the following faster than light method for communicating with deep space probes.

The solution relies on one of the properties of gravitons. Now as you keen physicists will be aware, the four forces (electromagnetism, gravity, strong, weak) are all caused by force carrying particles. For the electromagnetic force, for example the force carrying particle is the photon; particles under the influence of the electromagnetic force will emit and absorb photons thus changing their momentum and energy. Gravity uses the same mechanism and we call the force carrying particle the graviton.

Now gravity is different from the other forces in that it can be felt over long distances, a quality that tells us a great deal about the nature of gravitons. If 2 particles are 10 light minutes from each other, then any change in the gravity of one particle will not be felt by the other for 10 minutes. The traditional explanation for this is that the graviton can only travel at the speed of light and as such will take 10 minutes to travel from one particle to the other, so far so good. Unfortunately the situation breaks down if one of the particles is moving. As it won't be in the same position in 10 minutes time, the graviton should miss it and no gravity should be felt. As we know, however, gravity is always felt by moving bodies so the graviton must intercept the moving particle in order for the force to be expressed. By conventional theory the graviton must 'know' where the particle will be in ten minutes time.

Now perhaps that doesn't seem unreasonable but if you move the particles 10 light years apart then things get a bit more tenuous. As the graviton would take 10 years to travel the distance, this means that the particles must 'know' where each other are going to be in 10 years time. This is quite frankly ridiculous!

The explanation is in fact that the gravitons do not move at the speed of light but instead are exchanged instantaneously with their effects not being felt until a time equal to the distance between the 2 particles divided by the speed of light. In this way the rule limiting the exchange of information is kept intact and the rules of physics remain unchanged. We can however use this quality to solve our problem of communicating with deep space probes. Think of it as follows.

Here in the lab we have a massive ball which emits a large number of gravitons. As previously mentioned these gravitons will instantly arrive at our deep space probe regardless of how distant it actually is, but will not act on it until some time later. The key part is that we have a graviton detector on our probe which measures the number of gravitons received. By changing the mass of the ball (simple enough to do with a powerful laser) we can cause the number of gravitons detected by the probe to fluctuate and thus transmit a signal. As gravitons travel instantaneously the signal travels instantaneously and we have faster than light communication. Although the system is never going to carry gigabits (changing the mass of the ball is difficult to do on a picosecond time interval) it should be enough to perform simple operations such as steering the probe or powering on systems, thus revolutionising space travel.

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