Where can I find information on solving for new energies using Dirac notation?

theFuture
Messages
80
Reaction score
0
So in my problem set I'm asked to solve for the "new energies of the system" I'm given the initial energies of this system and told a new potential is added. I know all the matrix elements. I solved for H|psi> so where do I go from here for the energies?
 
Physics news on Phys.org
I'm not sure, but can't you just solve H|psi> = E |psi> for the new Hamiltonian which is defined by

H=-hbar^2/2m Laplacian +Vold+Vnew
 
That's what I was thinking but I was curious if there was some other trick buried in the Dirac stuff. Thanks.
 
The lecturer might be asking you to use pertubation theory - is the new potential small compared to the old?


Kane
 
I think Kane is right.

You can check wikipedia about the Dirac notation.
 
Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
Is it possible, and fruitful, to use certain conceptual and technical tools from effective field theory (coarse-graining/integrating-out, power-counting, matching, RG) to think about the relationship between the fundamental (quantum) and the emergent (classical), both to account for the quasi-autonomy of the classical level and to quantify residual quantum corrections? By “emergent,” I mean the following: after integrating out fast/irrelevant quantum degrees of freedom (high-energy modes...

Similar threads

Replies
9
Views
2K
Replies
3
Views
1K
Replies
10
Views
2K
Replies
82
Views
10K
Replies
5
Views
3K
Back
Top