Graph theory: minors vs topological minors
By Daniel Rodriguez •
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This is related to a previous question, Robertson-Seymour fails for topological minor ordering? (I.e., subgraphs and subdivision), but is much simpler.
What is a simple example of two graphs $G$ and $H$ such that $G$ is a minor of $H$ but not a topological minor? This would help me understand the difference between the two concepts.
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$\begingroup$Consider the standard cube $Q^3$ on $8$ vertices as $H$. Choose as $G$ the wheel $W^4$ on $5$ vertices. See also the following picture:
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Then, $G$ is a minor of $H$ but not a topological minor.
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