Stern Gerlach Experiment, bra(c)kets etc

[bugatti79]

Hi all,

This is my first post to the physics forum. I am completely new to quantum physics and have just gone through lecture notes on the Schrödinger equation, infinite square well, hydrogen atom and angular momentum etc.
I am currently starting on the Stern-Gerlach experiment, bras and kets via Sakurai’s Modern Quantum mechanics book. In general terms,

• Why do we have to use kets, bras and operators (Vectors Spaces) and for what?
• What’s their significance both mathematically and physically?
I suspect that as I study it further it might become clearer but at the moment I am going in blind.

Thanks

 

[vanhees71]

Dirac's bra-ket formalism is first of all an ingenious invention of a very helpful notation.

Also one should emphasize that quantum theory is not well understood, if one thinks in terms of wave mechanics only about it, and older textbooks overemphasize the wave-function approach. A full understanding of quantum theory can imho only be reached when learning the abstract formalism in terms of the abstract Hilbert-space formalism. The textbook by Sakurai is excellent. So just go ahead!

 

[bugatti79]

Ok Thanks