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| bio | website | wildcatsformma.wordpress.com |
|---|---|---|
| location | Somewhere over the rainbow | |
| age | ||
| visits | member for | 1 year, 6 months |
| seen | 9 hours ago | |
| stats | profile views | 145 |
My scientific interests:
- Mathematics: Category Theory, Algebra, Logic (Model-Theory, ATP), Control Systems
- Physics: General Relativity, QFT
- Amateur Astronomer and Astrophotographer
- Mathematica programming
My Website:WildCats
Premiere Mathematica package for category theory
Visit the newly launched Mathematica.SE!
My non-scientific interests:
- Skiing, Sailing, Windsurfing
- Argentine Tango dancer
More or less fluent in (random order):
Italian, English, German, French, Spanish, Dutch and struggling with Russian
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Jan 7 |
answered | First-order vs. set-theoretic group theory |
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Jan 7 |
revised |
Applications of Logic and Algebra in Computer Science Edited some small typos |
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Jan 7 |
revised |
Constructing a semigroup from a small category Added a clarification |
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Jan 7 |
revised |
Applications of Logic and Algebra in Computer Science Edited small typos |
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Jan 7 |
suggested | suggested edit on Applications of Logic and Algebra in Computer Science |
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Jan 7 |
suggested | suggested edit on Applications of Logic and Algebra in Computer Science |
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Jan 7 |
suggested | suggested edit on Constructing a semigroup from a small category |
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Jan 5 |
revised |
In search of proof that $\widetilde{e^{ix}}:\mathbb{R}\to S^1$ is not epic in $\mathbf{hTop}$ Edited and better formatted smnall part of text |
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Jan 5 |
suggested | suggested edit on In search of proof that $\widetilde{e^{ix}}:\mathbb{R}\to S^1$ is not epic in $\mathbf{hTop}$ |
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Dec 25 |
revised |
Can someone explain the Yoneda Lemma to an applied mathematician? replaced they with their, Grp in boldface |
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Dec 25 |
suggested | suggested edit on Can someone explain the Yoneda Lemma to an applied mathematician? |
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Dec 21 |
answered | Lawvere category of categories for foundations |
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Dec 21 |
comment |
Lawvere category of categories for foundations yes I also looked for it unsuccessfully. |
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Dec 19 |
comment |
(First order predicate calculus) Show that the theory of the equality axioms isn’t complete You seem to be good at model-theory. You might like to take a look at my other question math.stackexchange.com/q/92258/19609 |
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Dec 19 |
comment |
(First order predicate calculus) Show that the theory of the equality axioms isn’t complete I agree with you. Actually, by the same argument, ∀x∀y φ(x,y) is unprovable. Yet I am a bit puzzled...This question looks like a problem from a textbook and it looks like there is more to it then what is described here. Let's see if the OP comes up with a comment |
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Dec 19 |
awarded | Commentator |
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Dec 19 |
comment |
(First order predicate calculus) Show that the theory of the equality axioms isn’t complete I would like to edit my previous comment, but i do not see how.So - in my previous comment - please replace the sentence:"if you allow...." with "If you alllow φ to be any other binary relation (that is different from "=") , then your signature has infinite binary relations, so it is in fact a scheme". |
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Dec 19 |
comment |
(First order predicate calculus) Show that the theory of the equality axioms isn’t complete Well...is it or is it not? Can someone please formally prove that it is unprovable? |
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Dec 19 |
comment |
(First order predicate calculus) Show that the theory of the equality axioms isn’t complete What is the signature of your model? if it is just "=" as a binary relation, then φ(x,y) (being atomic) can only be x=y, it seems to me. If you allow φ to be any (also non atomic) formula, then your signature has infinite binary relations. Also: the sentence "And any model of these axioms is an equivalence relation" simply means that the "=" theory also has the axioms of an equivalence theory (for ex. x=y and y=z → x=z). Am I correct? |
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Dec 17 |
comment |
Logic and Sets Expressions @asaf there are set theories that use urelementen (that is non sets). But this is beside the question of the OP. What i wanted to stress is that "set" has nowadays a technical meaning. A "set" is supposed to obey to some axiomatic set theory. But in general logic you may have collections that do not obey any (well-known) set theory. Or if it satisfies one theory, it may not satisfy another one. |
