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Consider the release of a single photon or electron into a vacuum. The particle will have an initial trajectory. How is it possible for this event to give rise to a wave that has a continuously changing trajectory?
Consider the release of a single photon or electron into a vacuum. The particle will have an initial trajectory. How is it possible for this event to give rise to a wave that has a continuously changing trajectory?
Will it have an initial trajectory? QM is not like that - you in general cant describe quantum systems that way. It will likely have a well defined momentum, but that has a different meaning than classically.
Unless observed it only has this thing called a state.
States sometimes when expanded in eigenfunctions of position are wave like, but are not a wave in the normal sense used in physics such as a water or EM wave. A single particle in a definite eigenstate of momentum is wave-like in eigenstaes of position.
Thanks
Bill
Does the state permit the particle to be in 2 locations simultaneously?
Of course not.
It is only ever observed to be in one place at a time.
What's going on when not observed is however anyone guess - the theory is silent about that.
Thanks
Bill
If we then consider an EM wave at its inception (where I assume it would have a specific trajectory as the result of the event that gave rise to it) how is it considered that the wave continues to oscillate? Is an EM wave considered to consist of matter?
If we then consider an EM wave at its inception (where I assume it would have a specific trajectory as the result of the event that gave rise to it) how is it considered that the wave continues to oscillate? Is an EM wave considered to consist of matter?
This is not a quantum question - its a classical EM question.
But basically changing electric fields create changing magnetic fields ad infinitum.
Quantum mechanically it consists of photons. Its purely a semantic issue if a photon is matter or not - for me the answer is no - matter has a rest mass - photons do not.
Thanks
Bill
This seems to be something of a chicken and egg scenario. How is it understood that the change in an electric field occurs in order to then cause the change in magnetic fields?
If we consider the EM wave or the electric field as consisting of zero mass particles then an individual particle will have a trajectory at a given instant. How can it be explained that such a particle can be influenced by another such particle to alter its trajectory?
This seems to be something of a chicken and egg scenario. How is it understood that the change in an electric field occurs in order to then cause the change in magnetic fields? If we consider the EM wave or the electric field as consisting of zero mass particles then an individual
If we then consider an EM wave at its inception (where I assume it would have a specific trajectory as the result of the event that gave rise to it) how is it considered that the wave continues to oscillate?
All waves (water waves, sound waves, any system whose behavior is described by the wave equation - google for "wave equation") have this chicken and egg problem. The answer to this chicken/egg question is also the same for all of them: there has to be some initial disturbance to start things going. In the case of an electromagnetic wave, the wave starts when a charged particle is accelerated; this causes a change in the electric field nearby, which causes a change in the magnetic field a bit further away, which causes a change in the electric field a bit further away... And we have a wave. If you can get hold of Purcell's E&M textbook you'll find a good explanation, less mathematically demanding than most, of how this happens.This seems to be something of a chicken and egg scenario. How is it understood that the change in an electric field occurs in order to then cause the change in magnetic fields?
It can't be explained, but all that proves is that you cannot think of an electrical field as consisting of zero mass particles. That's just not what it is, and the massless photons and other particles that appear in quantum field theories do not act anything like the classical particles that you're thinking of.If we consider the EM wave or the electric field as consisting of zero mass particles then an individual particle will have a trajectory at a given instant. How can it be explained that such a particle can be influenced by another such particle to alter its trajectory?