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Sorry if this is too trivial:

I need an actual working definition of the term: Hopf band. I see references to it

in many searches, but never an actual precise definition. All I know so far is that it

is a Seifert surface for the Hopf link ( the disjoint union of two unknots $S^1$) , but this obviously

does not narrow things enough to an actual definition, since there is more than one

Seifert surface for every unknot. I've spent around an hour looking for a precise working definition.

How do people actually find these definitions?


EDIT: I found a "definition" ( a picture, aka, 1000 words ) in page 135 of:

I did not know one could do a search over all books. I'll try to remember that.

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It's a band with a full $2\pi$ twist in it. – Grumpy Parsnip May 9 '14 at 0:43
@Grumpy Parsnip .Thanks; a meta-question: how does one find a precise definitions for these terms? I searched for this for around one hour. And I've had similar problems finding precise technical definitions. – user99680 May 9 '14 at 0:45
I think girls call it a "skipping rope". – Pedro Tamaroff May 9 '14 at 0:55
@Pedro, Grumpy: Thanks; I found the answer in Google books; I did not know one could search for the term over all books. It is here:… – user99680 May 9 '14 at 0:57
By band, I assume this is a twisted 2-handle, right? – user99680 May 9 '14 at 1:01

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