11,491 reputation
33798
bio website boolesrings.org/asafk
location Israel
age 29
visits member for 4 years, 6 months
seen 2 hours ago

Born and raised in Israel. Ph.D. student in the Hebrew university in Jerusalem; studying set theory.


Dec
22
comment Sierpinski's construction of a non-measurable set
If you want to be correct, $[\Bbb R]^{\aleph_0}$, since $|\Bbb R|^{\aleph_0}=|\Bbb R|$ requires no choice whatsoever.
Dec
22
comment Sierpinski's construction of a non-measurable set
@Avshalom: Thank you! I'll look up the reference in the answer. If I can find it (or maybe if you can find it) and it is not in English, I'll let you know.
Dec
22
comment Complete resolutions of GCH
Interesting, thanks. I had the impression that there were some problems there, but maybe I was wrong.
Dec
22
comment Complete resolutions of GCH
As for the final part, are you sure that these are all the restrictions? I think that with those you need to restrict $F$ to regular cardinals, or at least add some additional restriction for limit cardinals. I'm not sure that you can get every possible function like that.
Dec
22
asked Sierpinski's construction of a non-measurable set
Dec
20
comment What's so special about $1$-categories?
It's been said that $1$ is the loneliest number. That's pretty special.
Dec
20
comment Application of the Riemann hypothesis and the ABC conjecture to independence results
@Todd: Thanks in advance! (And in retrospect, I suppose.)
Dec
20
revised Complete resolutions of GCH
added 76 characters in body
Dec
20
comment Complete resolutions of GCH
You asked a good question, which has several sub questions, none of which is trivial. It is usually not the best idea to accept an answer after an hour or so.
Dec
18
answered Is there a “natural” bijection between models of $ZFC$ and $ZF\neg C$?
Dec
18
comment When does Skolemization require the axiom of choice?
Everyone knows that second-order logic is set theory in sheep clothing. "Bahhh... baahhhh..."
Dec
18
revised When does Skolemization require the axiom of choice?
edited tags
Dec
18
answered When does Skolemization require the axiom of choice?
Dec
14
comment Existential statement without witness
"Shape without form, shade without colour, Paralysed force, gesture without motion" -- T.S. Eliot, The Hollow Men.
Dec
10
comment Are there known ways to posit definable global choice in ZF without positing V=L?
@Mohammad: To be accurate, global choice can be forced over models of $\sf NBG+AC$ without adding sets. Doing this over models of $\sf ZFC$ requires us to extend the language by adding a the generic class. Sure, this is not an actual issue, but it's more accurate this way.
Dec
9
comment Does a left basis imply a right basis, without AC?
I have to admit, that on a normal day I'd have jumped into some books to better my understanding of the objects in question, many of which I haven't actually met on the mathematical playground. But nowadays I'm too darn busy with my own work to do that. So I apologize, perhaps some other day!
Dec
8
comment countable OD sets in the Solovay model
Sorry, it just really bugged me, I had to edit it. :-)
Dec
8
revised countable OD sets in the Solovay model
added 23 characters in body
Dec
8
comment First-order definable bijection between $P(On)$ (or $No$) and $V$? (Is this equivalent to $V = HOD$?)
Yeah, given the edit it's less duplicate. :-)
Dec
8
comment First-order definable bijection between $P(On)$ (or $No$) and $V$? (Is this equivalent to $V = HOD$?)
Essentially a duplicate, maybe, mathoverflow.net/questions/110799/…