I Physical parameters for spin 1/2 particles

[lazayama]

I am having trouble to understand what it means by "physically relevant real parameters" and how does it help us to specify a quantum system.

Let say, we have a state of k half spin electrons? My guess is about the local phase of the spin, and this would make it 2^k parameters since each electron has 2 parameters?

What am I missing?

 

[PeroK]

Could you give an example of what you mean by parameters here? Perhaps for a system of 2 or 3 electrons.

Are you talking about the dimension of the Hilbert space of spin states?

 

[lazayama]

Thanks for helping!
The book I am looking has mentioned something like global phase / local phase but I don't quite understand, and how does it related to physical REAL parameter and also describe the state of k half spin electron quantum system?

 

[Nugatory]

The book I am looking

Which book? You will get way better and more helpful answers if we have more context here.

 

[lazayama]

This is not a published book but a material our instructor gave us, and there is a problem asking us about this, so I am quite confused.
Sorry about the confusion as well!

 

[PeterDonis]

I am having trouble to understand what it means by "physically relevant real parameters"

If we are unable to look at what "it" says directly, I have no idea how to help with this. Are the materials you refer to online? Or can you at least quote more context from them?