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Virtual particles and velocities greater than C

  1. Oct 17, 2006 #1
    i know that virtual particles are a result of the uncertainty principle and that most of the time they are annihilated but i also think i read that sometimes they come into being when they receive an energy boost? im thinking maybe an errant photon?

    also ive read about velocities of greater than C observed with close proximity to a photon already traveling at C but that as soon as they (waves :confused: ) leave the vicinity of the photon that they evaporate and so essentially its pointless. the impression from the reading i got was that it was akin to being stationary versus moving a long with a cloud of gas and how being in the cloud would give you a higher kinetic energy... about this last topic i was just wonder if anyone remembers any research like this and could maybe point me in the right direction in finding it.


    forgive my n00bness
    Last edited: Oct 17, 2006
  2. jcsd
  3. Oct 17, 2006 #2


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    The idea of a virtual particle becoming real is indeed mystiftying. However, it the mechanism by which Black Holes are predicted to evaporate. Of course, this means mass from inside the Event Horizon of the Black Hole is getting outside, which pretty much demands that something has travelled faster than light.

    You probably already know the basic idea; that the energy always present everywhere in the universe is constantly producing VP's in pairs, one matter and one antimatter. The two are then drawn immediately into one another where they annihilate and become energy once again. The idea fo Black Hole Radiation (and I suppose this would work in any space that is curved by gravity) is that a particular packet of anergy produces a Virtual Particle Pair, at high energy (travelling at great velocity). This VPP might come into existance at just the right distance from the center of the gravitational field so that one is just barely too close, and their speed is less than Escape Velocity, while the other VP is just far enough out that their soeed is just barely above Escape Velocity. So one particle escapes and becomes real. Once this idea is accepted, any number of other phenomina may be applied to the theory (like one VP anihilating with something else before the pair can anihilate with each other, or on gaining an energy boost greater than the magnetic attraction between the two) and a whole Pandora's Box seems to open up.
  4. Oct 17, 2006 #3
    Is it possible to create regions of space with a lower amount of charged virtual particles? Maybe between two plane metal plates, as in the Casimir effect?

    In that case, would electromagnetic properties of space, namely mu_0 and epsilon_0, change? Having less charged particles, should epsilon_0 decrease? So should light's speed c increase?
    Last edited: Oct 18, 2006
  5. Oct 18, 2006 #4
    This may be off topic a bit, but is it possible that all objects are capable of velocities faster than C, if we assume C is a relative velocity? For example if an object is travelling at a velocity of 64 mi/s, is C actually 180,064 mi/s? Are objects just unable to have acceleration values approaching the "acceleration of light"? The only problem is the incredible amount of energy it takes to accelerate 99.9999% of the speed of light. Assuming X object weighs 100 units, and is travelling at 64mi/s, it would take alittle less than 3.2 trillion units of energy to accelerate approaching the speed of light if you were impatient.

    If you accelerated at a much smaller rate (half), couldn't you theoretically reach the relative speed of light, and exceed it, using the amount of energy halfway down the exponential graph of energy it takes to reach the acceleration of light? This would increase time, but decrease energy required significantly.
  6. Oct 18, 2006 #5
    M.q.: Whether you are stationary on earth, or on a train at 64mi/s, you will still measure the same speed for light. This is the basis of relativity theory.
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