Questions tagged [hardy-fields]
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4 questions
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In surreal numbers, what exactly is $\omega_1$?
This answer refers to $\omega_1$ in context of surreal numbers, and calls it "first uncountable ordinal".
But what exactly does it mean? How can it be represented in the $\{L|R\}$ form?
How ...
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Representing the set of rationals $\mathbb{Q}$ as a germ or surreal number
Let us define natural equivalence between elements of Hardy fields and integrals of Dirac comb-like functions.
Let us assume a natural embedding of Hardy field into surreal numbers ($[x]=\omega$). ...
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Why is it said that all surreal numbers with birthdate $<\omega_1$ are isomorphic to a Hardy field?
In this answer I have encountered with the following statement:
Assuming CH, every maximal Hardy field is isomorphic to
$(\bf{No}(\omega_1), \partial_{\omega_1})$, where $\bf{No}(\omega_1)$
is the ...
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In surreal numbers, do the automorphisms allow us to define $\omega_2=\partial(\omega_1)$?
Consider surreal numbers as an H-field with operation of derivation.
In such setting for any surreal number $\alpha$ such that $0<\alpha<e^\omega$, $\partial(\alpha)<\alpha$ and for $\alpha&...