Difference between Hamiltonian operator and Total energy operator?

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The Hamiltonian operator and the total energy operator are often considered equivalent in quantum mechanics, both representing total energy in different contexts. The confusion arises from their presentation in textbooks, where they may appear distinct despite serving the same purpose in equations like H ψ = E ψ. The time-dependent Schrödinger equation includes a term (ih ∂/∂t) that describes the evolution of the wave function, but it is not the energy operator. This term has different implications in various formulations of quantum mechanics, such as the Heisenberg and interaction pictures. Understanding these nuances clarifies their roles without implying they are fundamentally different operators.
annms
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What is the difference between the Hamiltonian operator and the Total energy operator? If both is used when working with total energy, why are there two different operators?
 
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They are both sides to the same equation. Hamiltonian = H and total energy = E.
H \psi = E \psi
 
annms said:
What is the difference between the Hamiltonian operator and the Total energy operator? If both is used when working with total energy, why are there two different operators?

As far as I am aware, they are one and the same. What was the context that led you to think they might be different?
 
Thank you for the responses guys. Forgive me for asking such a stupid question, I am a newbie to quantum mechanics. I was just reading my textbook and it first listed the total energy operator, then a few pages later it listed the Hamiltonian operator. It just looked very different than the total energy operator to me so I guess I was confused. Thanks again for the responses.
 
In the time-dependent Schrodinger Equation (ih ∂/∂t) ψ = H ψ, people sometimes mistakenly refer to the left hand side ih ∂/∂t as the energy operator. It is not, of course, it merely describes how ψ(x, t) evolves with time. It does not appear in the time-independent Schrodinger equation H ψ = E ψ, and it appears but has a different meaning in other "pictures", e.g. the Heisenberg picture in which (ih ∂/∂t) ψ = 0 and the time evolution is cast onto the operators themselves, or the interaction picture in which (ih ∂/∂t) ψ = Hint ψ where Hint is the interaction Hamiltonian.
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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