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University Quantum Mechanics I

University Quantum Mechanics I · The Schrödinger Equation · 2.03

Separation of variables and the constant E

Try Ψ(x, t) = ψ(x) f(t) and divide by it: each side then depends on one variable alone, so both equal a constant, and f(t) = exp(−iEt/ℏ) follows.

Course-map guide · not a complete lesson or simulation

Scope & orientation

What this subsection covers

Try Ψ(x, t) = ψ(x) f(t) and divide by it: each side then depends on one variable alone, so both equal a constant, and f(t) = exp(−iEt/ℏ) follows.

A strong response uses level ladders beside their eigenfunctions and states where the model stops being reliable.

Reasoning checklist

Evidence, assumptions and limits

01

Assumptions to state

State the system, observable, approximation, and conditions held fixed before using a model.

02

Evidence to collect

Does a numerically evolved packet hold its norm constant, and does the probability lost from an interval match the current integrated through its two edges?

Read the complete note

Does a numerically evolved packet hold its norm constant, and does the probability lost from an interval match the current integrated through its two edges? Useful evidence includes ψ(x, t) from a stated integrator and grid, total norm against time, interval norm compared with the integrated flux at both edges, the drift traced to the time step, and the box edge named as the leak..

03

Limits to state

This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus.

Read the complete note

This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus. It is a first dedicated quantum-mechanics course, distinct from University Physics V, which covers quantum mechanics alongside atomic, nuclear and particle physics in twenty units: this course is narrower, slower, and teaches the linear algebra it needs rather than assuming it. Hydrogen appears here as an introduction, with the full radial derivation belonging to a second course. A midterm examination is assumed around week 8. Follow your institution's published scope, notation, laboratory programme, and assessment rules. A result should be checked against units, signs, limiting cases, and the conditions under which its model was derived.

Diagram & examples

Work the claim before choosing an equation

Interactive concept map

Follow the model from claim to evidence.

01 · Physical claimSeparation of variables and the constant E

Try Ψ(x, t) = ψ(x) f(t) and divide by it: each side then depends on one variable alone, so both equal a constant, and f(t) = exp(−iEt/ℏ) follows. The trick needs V independent of t, and it returns special solutions, not the general one.

02 · RepresentationThe subsection's claim

Model, evidence, and boundary

03 · TestPrediction before measurement

What must be stated before selecting an equation for Separation of variables and the constant E?

04 · Evidence & boundaryDecide, then qualify

Does a numerically evolved packet hold its norm constant, and does the probability lost from an interval match the current integrated through its two edges?

Read the complete note

Does a numerically evolved packet hold its norm constant, and does the probability lost from an interval match the current integrated through its two edges? Useful evidence includes ψ(x, t) from a stated integrator and grid, total norm against time, interval norm compared with the integrated flux at both edges, the drift traced to the time step, and the box edge named as the leak..

Interactive diagram for Separation of variables and the constant E: follow the physical claim through its representation, proposed test, evidence, and model boundary.

modelModel, evidence, and boundary turns the stated idea into a representation that can make a prediction.

Example questions

Try the reasoning before revealing the structure.

Diagram check

What must be stated before selecting an equation for Separation of variables and the constant E?

Quick check

Test the reasoning, not recall

What must be stated before selecting an equation for Separation of variables and the constant E?

Choose an answer to test the model.