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1 vote
1 answer
42 views

Find self-adjoint of $P=|a \rangle \langle b |$

Let $P$ be an operator s.a. $P=|a \rangle \langle b |$ and $P|f \rangle = \langle b | f \rangle | a \rangle $. Find the self-adjoint and the $P^2$ operator. My attempt: We know to find the self ...
lebong66's user avatar
  • 463
0 votes
1 answer
437 views

Show that the adjoint of two operators is the sum of the adjoints

Problem Show that for any two operators $\hat{A}$ and $\hat{B}$, the adjoint $(\hat{A} + \hat{B})^\dagger = \hat{A}^\dagger + \hat{B}^\dagger$. Do so using the integral form of the definition of ...
10GeV's user avatar
  • 1,381
0 votes
0 answers
27 views

Question regarding conjugate operators and the harmonic operator.

Let us consider the operator $\hat{n}=\hat{a}^\dagger\hat{a}$ as the number operator of the harmonic oscillator. Let $|n\rangle$ be the eigenstates. Then we can say : $$\hat{n}|n\rangle=n|n\rangle$$ I'...
Nakshatra Gangopadhay's user avatar
3 votes
2 answers
4k views

Definition of Adjoint Operator for Quantum Mechanics

While learning about adjoint operators for quantum mechanics, I encountered two definitions. The first definition is given by Shankar in The Principle of Quantum Mechanics: Given a ket $$ A\lvert ...
TaeNyFan's user avatar
  • 771
0 votes
0 answers
17 views

Necessary condition for Hermician lin operators

Let $H$ be a Hilbert space and define $T: H \to H$ as a linear unbounded operator. Say that the spectrum of $T$ is real and the eigenvectors are orthogonal and span the space. Does that imply that $...
Piotr Benedysiuk's user avatar
5 votes
1 answer
423 views

Schrodinger with real potential is self-adjoint?

Suppose I define the operator $$ -\frac{d^2}{dx^2}+V(x) $$ on the space of Schwartz class functions $\mathcal{S}(\mathbb{R})$ and take its closure to form the operator $H$ acting on a domain in $L^2(\...
Mathmo's user avatar
  • 1,035