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SemM
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I was wondering if anyone has worked with non-Hermitian wavefunctions, and know of an approach to derive real and trivial values for their observables using numerical calculations?
Cheers
Cheers
SemM said:I was wondering if anyone has worked with non-Hermitian wavefunctions, and know of an approach to derive real and trivial values for their observables using numerical calculations?
Cheers
PeroK said:Your posts are fascinating. You seem to be ploughing through QM without having learned the basics - and having no intention of learning the basics. Perhaps eventually you will be able to put things together consistently without ever having learned, say, the definition of and difference between a vector and an operator!
Personally, I doubt it. I recommend a first course in linear algebra.
DrClaude said:What's a non-Hermitian wave function?
I'm not aware of any significant work on the hermicity of wave functions. In QM, what is important is the hermicity of operators, which is what the link you posted above is about. This is also, I think, what has triggered @PeroK's reply. You seem to be confusing operators and wave functions.SemM said:
This notation doesn't make sense to me. If you are using the Dirac notation, then there is no particular basis, so the ##d/dx## of a ket doesn't make sense. Likewise for the inclusion of a ##^*## in the ket, if it is to mean complex conjugation.SemM said:##\langle \psi | d/dx | \psi*\rangle##
It is difficult to use a common language here, because some are physicsts and some are mathematicians. This Dirac notation can also be given asDrClaude said:I'm not aware of any significant work on the hermicity of wave functions. In QM, what is important is the hermicity of operators, which is what the link you posted above is about. This is also, I think, what has triggered @PeroK's reply. You seem to be confusing operators and wave functions.
To come back to the OP, most often the eigenfunctions of Hamiltonians can be chosen purely real, so they are definitely not Hermitian functions.This notation doesn't make sense to me. If you are using the Dirac notation, then there is no particular basis, so the ##d/dx## of a ket doesn't make sense. Likewise for the inclusion of a ##^*## in the ket, if it is to mean complex conjugation.
This ha nothing to do with it. What you wrote simply does not make any sense. It is definitely not the same as you wrote in your last post. I would suggest taking three steps back and learn the fundamentals of Hilbert spaces and Dirac notation to represent elements in the Hilbert space.SemM said:because some are physicsts and some are mathematicians
I don't get it. The most common wave packet, a Gaussian wave packet, can be purely real, hence non-Hermitian.SemM said:Anyway, the solution to this problem is to construct wavepackets,
The problem is the questions you ask, along with the replies you give, show a lack of basic knowledge. It is extremely pedagogical for people to reply that you must take steps back and try and get proper basic knowledge first.SemM said:These conversations must yield an answer and not just critics, otherwise PF becomes a gladiator arena, with no pedagogic or informational role.
DrClaude said:I don't get it. The most common wave packet, a Gaussian wave packet, can be purely real, hence non-Hermitian.The problem is the questions you ask, along with the replies you give, show a lack of basic knowledge. It is extremely pedagogical for people to reply that you must take steps back and try and get proper basic knowledge first.
Let me translate what these threads of yours sound to me. OP: "What is the colour of a hydrogen atom?" Followed up by question asking what do you mean by color of an atom, and a back and forth about basic principles, to be concluded by you saying "You should simply have answered blue."
Non-Hermitian wavefunctions are mathematical functions that describe the behavior of a quantum system that does not satisfy the Hermitian property. This means that the wavefunction is not equal to its complex conjugate, leading to non-conservation of probability.
Non-Hermitian wavefunctions differ from Hermitian wavefunctions in that they do not obey the fundamental law of quantum mechanics, the conservation of probability. This is because the Hermitian property ensures that the total probability of finding a particle in a system is always equal to 1, while non-Hermitian wavefunctions do not have this property.
The solutions to non-Hermitian wavefunctions are complex-valued functions, as opposed to the real-valued solutions of Hermitian wavefunctions. These complex solutions must be interpreted differently, as they do not represent the physical state of the system, but rather the probability amplitudes of the system.
Non-Hermitian wavefunctions are used in quantum mechanics to describe systems that exhibit non-conservation of probability, such as open quantum systems. They are also used in studies of non-Hermitian Hamiltonians and non-unitary time evolution operators.
Non-Hermitian wavefunctions have applications in various fields, including quantum optics, solid-state physics, and quantum information processing. They are also being studied in relation to topological insulators and other novel quantum phenomena.