Rough Description of State Space

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SUMMARY

The discussion centers on the concept of state space in quantum mechanics, specifically addressing the nature of state vectors and their representation within a vector space. It is established that state space is a complex vector space with potentially infinite dimensions, contrary to the initial assumption of a finite number of discrete points. The importance of orthonormal bases, particularly eigenstates of observables, is emphasized, as they ensure orthogonality and facilitate the definition of the inner product, which is crucial for quantum mechanics.

PREREQUISITES
  • Understanding of complex vector spaces
  • Familiarity with quantum mechanics terminology
  • Knowledge of eigenstates and observables
  • Basic grasp of inner product and orthogonality concepts
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  • Study the properties of complex vector spaces in quantum mechanics
  • Learn about the role of eigenstates in quantum measurements
  • Explore the mathematical formulation of inner products in Hilbert spaces
  • Investigate the implications of orthonormal bases in quantum state representation
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Students of quantum mechanics, physicists, and anyone interested in the mathematical foundations of quantum theory will benefit from this discussion.

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I have done only a small bit of reading/studying of quantum mechanics. So, from what I have gathered thus far, I have the following rough semi-graphical description of state space:

Imagine a space in which you have a lot, but a definite number of discrete points. Each of those points (state vectors) can be described using a combination of base states with appropriate coefficients, provided that the dot/inner product between any two base states (base vectors) i, j is orthogonal (i.e. defined by the Kronecker delta function).

So, what I am wondering is if this is correct by any means. As aforementioned, my exposure to QM is minimal and therefore I may have this completely wrong. Thanks in advance.
 
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You're not that far off. The state space is just an ordinary (complex) vector space. It has an infinite number (in fact, a continuum) of points, just like an ordinary vector space, and often has in fact an infinite number of dimensions.

Like any vector space, it has many bases, not all of which are orthonormal, and while its not necessary to take an orthonormal basis, this is almost always done in practice because we usually take as a basis the eigenstates of some collection of observables, and such states are always orthogonal. Of course, since this space doesn't have an obvious geometric interpretation, you should be wondering where the inner product comes from, and a rough answer is that its define so that the last sentence I said is true.
 
Thank you for the clarification.
 

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