Can Quantum Mechanics Ket and Bra Methods Solve Scalar Equations?

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SUMMARY

The discussion focuses on solving scalar equations using quantum mechanics' ket and bra methods. The participants explore the normalization of kets, specifically ##\left|m\right\rangle = \frac{1}{\sqrt{A}}\binom{1-2i}{\alpha}## and ##\left|n\right\rangle = \frac{1}{\sqrt{14}}\binom{-3+2i}{\beta}##, and the implications of their orthogonality. Key equations include ##\langle n \mid n \rangle = \dfrac{1}{\sqrt{14}} \begin{pmatrix} -3-2i & \beta^* \end{pmatrix} \dfrac{1}{\sqrt{14}} \begin{pmatrix} -3+2i \\ \beta \end{pmatrix}##. The user confirms that the kets are orthogonal and is currently solving for the unknown constants A, α, and β.

PREREQUISITES
  • Understanding of quantum mechanics, specifically ket and bra notation.
  • Familiarity with normalization of quantum states.
  • Knowledge of complex numbers and their properties.
  • Basic linear algebra concepts, particularly matrix multiplication and transposition.
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  • Study the process of normalizing quantum states in detail.
  • Learn about the implications of orthogonality in quantum mechanics.
  • Research methods for solving scalar equations using matrix representations.
  • Explore the relationship between kets and bras in quantum mechanics, focusing on inner products.
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Homework Statement
##\left|m\right\rangle = \frac{1}{\sqrt{A}}\binom{1-2i}{\alpha} , \left|n\right\rangle = \frac{1}{\sqrt{14}}\binom{-3+2i}{\beta}##
Relevant Equations
Find unknown constants A, α and β, we know that β is real positive integer , α has both real and imaginary parts
Not really even sure how to approach this problem , I would guess if we need scalar answer we would need to combine these two given equations together but I'm unfamiliar with such methods, in the book there is methods to make a ket to a bra and then matrix part transposes and multiplies with the original while constant squares like:
##\left\langle m \right|\left|m\right\rangle = ({\frac{1}{\sqrt{A}}}^2)*\binom{1-2i}{\alpha}*(1-2i ,\alpha)##

Would that be an approach?
 
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Ugnius said:
Homework Statement: ##\left|m\right\rangle = \frac{1}{\sqrt{A}}\binom{1-2i}{\alpha} , \left|n\right\rangle = \frac{1}{\sqrt{14}}\binom{-3+2i}{\beta}##
Relevant Equations: Find unknown constants A, α and β, we know that β is real positive integer , α has both real and imaginary parts

Not really even sure how to approach this problem , I would guess if we need scalar answer we would need to combine these two given equations together but I'm unfamiliar with such methods, in the book there is methods to make a ket to a bra and then matrix part transposes and multiplies with the original while constant squares like:
##\left\langle m \right|\left|m\right\rangle = ({\frac{1}{\sqrt{A}}}^2)*\binom{1-2i}{\alpha}*(1-2i ,\alpha)##

Would that be an approach?
If you normalize ##\mid n \rangle##, then yes, you can find ##\beta##. But you would write this as
##\langle n \mid n \rangle = \dfrac{1}{\sqrt{14}} \begin{pmatrix} -3-2i & \beta^* \end{pmatrix} \dfrac{1}{\sqrt{14}} \begin{pmatrix} -3+2i \\ \beta \end{pmatrix}##
(You wrote your bra and ket in the wrong order for ##\langle m \mid m \rangle## in your OP.)

We know that ##\beta## is real, so ##\beta^* = \beta##, and you can go from there.

To find A and ##\alpha## we need to know something about how ##\mid m \rangle## and ##\mid n \rangle## relate to each other. Are they orthogonal? ie. ##\langle n \mid m \rangle = 0##?

-Dan
 
Thank you.
They are orthogonal yes , I'm brute forcing the solution right now , I solved for \beta. Now I need to solve \langle n \mid m \rangle = 0 and i'll get back to you for confirmation if I did it correctly
 

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