Stimulated Emission & Emitted photon direction

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RobbyQ
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Stimulated Emission & Emitted photon direction
I always understood that a photon of correct wavelength would raise the energy level of an electron (which is the case)
But reading about lasers and stimulated emission I read the following where the electron drops a level upon absorption:-
"A photon with the correct wavelength to be absorbed by a transition can also cause an electron to drop from the higher to the lower level, emitting a new photon. The emitted photon exactly matches the original photon in wavelength, phase, and direction. This process is called stimulated emission."

How is this possible i.e dropping to a lower energy level and how/why is the photon wavelength, phase, and direction preserved?
 
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Stimulated emission-absorption equations would be exchanged if performing CPT symmetry, suggesting they are CPT analogs - also through B_{12}=B_{21} symmetry for their Einstein's coefficients.

If so, and absorption is from positive radiation pressure, pushing photons into a target (from given direction) ... maybe we should think about stimulated emission through negative radiation pressure, pulling of photons (in given direction)?
https://scholar.google.pl/scholar?q=negative+radiation+pressure
https://www.physicsforums.com/threads/negative-radiation-pressure.1053657/
 
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