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Ahmed1029
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What's the difference between a bra vector and ket vector in specifying spin states except for notational convenience when calculating probablility amplitudes? Are they equivalent?
A ket is a vector and a bra is a vector in the dual space:Ahmed1029 said:What's the difference between a bra vector and ket vector in specifying spin states except for notational convenience when calculating probablility amplitudes? Are they equivalent?
Ahmed1029 said:What's the difference between a bra vector and ket vector in specifying spin states except for notational convenience when calculating probablility amplitudes? Are they equivalent?
The dual space (bras) is isomorphic to the space of kets. But, conceptually and notationally there are still two vector spaces here. Especially if we are using Dirac notation.andresB said:In the case of spin states, there answers is that there is no difference. This is because we are dealing with finite-dimensional vector spaces.
Well, yes. Still, you can use one or the other space to compute probabilities and expected values in a very similar way, and that was the op question.PeroK said:The dual space (bras) is isomorphic to the space of kets. But, conceptually and notationally there are still two vector spaces here. Especially if we are using Dirac notation.
Expressed in a fixed basis, the bra is a row vextor and the ket is a column vector.Ahmed1029 said:What's the difference between a bra vector and ket vector in specifying spin states except for notational convenience when calculating probablility amplitudes? Are they equivalent?
Bra and ket notation is a mathematical notation used in quantum mechanics to represent vectors and operators. The bra notation represents a vector in a complex vector space, while the ket notation represents the dual vector.
Bra and ket notation is used in quantum mechanics to represent the state of a quantum system. The bra notation is used to represent the state of the system before a measurement is made, while the ket notation is used to represent the state after a measurement is made.
The main difference between bra and ket notation is that the bra notation represents the dual vector, while the ket notation represents the vector itself. This allows for a more compact and elegant representation of quantum states and operators.
Bra and ket notation is a part of Dirac notation, which was developed by physicist Paul Dirac to simplify the mathematical description of quantum mechanics. Dirac notation includes the use of bras, kets, and the inner product