Bra-ket notation and other linear algebra stuff

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SUMMARY

The discussion focuses on the application of bra-ket notation in linear algebra, specifically addressing the use of complex conjugates and unit matrices in matrix operations. Participants clarify that the row vector should indeed represent complex conjugates, and the second unit matrix is necessary for converting a column vector into a transposed form. The confusion surrounding the hermitian property of vector 'a' in the expression < a | b > is also highlighted, emphasizing the importance of understanding these concepts in quantum mechanics and linear algebra.

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  • Understanding of bra-ket notation in quantum mechanics
  • Familiarity with complex conjugates in linear algebra
  • Knowledge of matrix operations, including unit matrices
  • Basic principles of hermitian matrices
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  • Study the properties of hermitian matrices in linear algebra
  • Learn about complex conjugates and their significance in quantum mechanics
  • Explore the implications of bra-ket notation in quantum state representations
  • Investigate matrix multiplication and the role of unit matrices in transformations
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Students of quantum mechanics, linear algebra enthusiasts, and anyone seeking to deepen their understanding of bra-ket notation and matrix operations.

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forgive the messiness; i take bad notes in class.

http://i.imgur.com/VmW8Ubg.jpg

towards the middle of the page where it says "this is equivalent to..." and then my professor wrote what follows but i thought the row vector should be complex conjugates? ie, the red writings are not actually part of the notes, i just wrote them because i was confused as to why they weren't there.
http://i.imgur.com/5zGGBe3.jpg

towards the bottom right, where it has a(hermitian)IbI, which are all matrices by the way, i don't understand where the second 'I' (unit matrix) came from (where i stated my confusion in the notes).btw, does anyone know how to shrink an image when i do ['img']link['/img']? sometimes these images are too large
 
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Your first remark is correct. They should be complex conjugates.

For the second part if you have numbers like a\cdot u^{-1} \cdot u \cdot b.
Than you get a\cdot 1\cdot b. you can freely multiply this entire expression with 1.

I believe the second unit matrix is added to convert the vector b in the transposed vector b since otherwise you have the product of 2 column vectors.
 
towards the bottom of the page where i wrote "where'd this one come from?", to the RHS of that, i have 'ab'.

but if this is to become < a | b > , then shouldn't the 'a' in 'ab' be hermitian?
 

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