Timeline for What is "van Dyck's theorem"

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Nov 15 at 7:42	comment	added	Bruno Stonek		@GregorSamsa: the homomorphism constructed by Jeremy is not an epimorphism in general. Hungerford supposes that the $h_i$ are generators of $H$, which is not a hypothesis in what Jeremy wrote above.
Dec 2, 2013 at 20:47	comment	added	Gregor Samsa		Hungerford attributes a slightly stronger theorem in his algebra text to Van Dyck, see Theorem 9.5 on page 67. It says that the homomorhpism above is in fact an epimorphism. This means that group given by generators and relations is largest possible such group in a sense.
Dec 1, 2013 at 20:12	comment	added	Jim Humphreys		@Jeremy: My understanding (from the historical study by Chandler and Magnus, Springer, 1982) is that W. van Dyck was a foounder of combinatorial group theory: Math. Ann. 20 (1882), 1-44. In particular, he helped to make rigorous the initial ideas about free groups and groups given by generators and relations, as you indicate. Those with access to MathSciNet can find somewhat more detail than Google, though of course there is no review of van Dyck's old paper as such.
Dec 1, 2013 at 11:45	comment	added	Victor		Thank you, Jeremy! It is hard to beleive that Hickin used phrasing "Dyck theorem" for this fact since it would strangely match his tricks he uses in the proof; and also it's quite hard to see any projection from one group in another. But may be it's exactly what he meant
Dec 1, 2013 at 11:11	history	answered	Jeremy Rickard	CC BY-SA 3.0