- #71
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The longer the thread gets, the more misconceptions are accumulated :-(.
Photons are massless quanta with spin 1. They are as relativistic as it can get, and you cannot apply naive one-particle wave-mechanics ideas from non-relativistic physics, let alone classical particle or wave concepts to them.
First of all, photons have no well-defined position observable in the strict sense. See Arnold Neumaier's Theoretical-Physics FAQ:
http://arnold-neumaier.at/physfaq/topics/position.html
It doesn't matter, in which of the different possible formulations of non-relativistic wave mechanics (position representation, matrix mechanics, or path integrals as integrals over single-particle trajectories) you try to treat photons. It doesn't work!
The only consistent way to treat photons is QED. That's very intuitive, because photons are created and destroyed all the time when interacting with other stuff, and quantum field theory is the way to describe precisely such annihilation and creation processes of quanta.
That QED actually works is demonstrated in many high-precision ways in both high-energy particle physics, where it is part of the Standard Model of elementary particles, which hitherto is the most successful theory ever, and in quantum optics experiments, where particularly photons are used to demonstrate all the features of quantum theory that appear "most weird" from the point of view of classical physics and our every-day schooled intuition like entanglement ("hypercorrelations").
A very nice article on the topic (particularly on the socalled "wave-particle dualism", which is another outdated point of view, which seems to be impossible to kill in the popular-science literature) is the following article on phys.org:
http://phys.org/news/2014-07-particle-optical-qubit-technique-photons.html
Photons are massless quanta with spin 1. They are as relativistic as it can get, and you cannot apply naive one-particle wave-mechanics ideas from non-relativistic physics, let alone classical particle or wave concepts to them.
First of all, photons have no well-defined position observable in the strict sense. See Arnold Neumaier's Theoretical-Physics FAQ:
http://arnold-neumaier.at/physfaq/topics/position.html
It doesn't matter, in which of the different possible formulations of non-relativistic wave mechanics (position representation, matrix mechanics, or path integrals as integrals over single-particle trajectories) you try to treat photons. It doesn't work!
The only consistent way to treat photons is QED. That's very intuitive, because photons are created and destroyed all the time when interacting with other stuff, and quantum field theory is the way to describe precisely such annihilation and creation processes of quanta.
That QED actually works is demonstrated in many high-precision ways in both high-energy particle physics, where it is part of the Standard Model of elementary particles, which hitherto is the most successful theory ever, and in quantum optics experiments, where particularly photons are used to demonstrate all the features of quantum theory that appear "most weird" from the point of view of classical physics and our every-day schooled intuition like entanglement ("hypercorrelations").
A very nice article on the topic (particularly on the socalled "wave-particle dualism", which is another outdated point of view, which seems to be impossible to kill in the popular-science literature) is the following article on phys.org:
http://phys.org/news/2014-07-particle-optical-qubit-technique-photons.html