658 reputation
57
bio website math.huji.ac.il/…
location Jerusalem
age 28
visits member for 2 years, 10 months
seen 5 hours ago

May
26
awarded  Enlightened
May
26
awarded  Nice Answer
May
21
answered Graph on the set of all functions $f:\mathbb{N}\to\mathbb{N}$
May
20
awarded  Enlightened
May
20
awarded  Nice Answer
May
20
awarded  Yearling
May
20
awarded  Editor
May
20
revised Graph $G$ with $\omega(G) = 2$ but $\chi(G) \geq \aleph_0$
added 293 characters in body
May
20
answered Graph $G$ with $\omega(G) = 2$ but $\chi(G) \geq \aleph_0$
May
9
answered monochromatic cycle-free colouring of the complete graph on R?
Apr
24
comment name for an intermediate notion between huge and 2-huge
In Magidor and Shelah's paper, "The tree property at successors of singular cardinals," a cardinal $\kappa$ is called $\tau$-huge if there is an elementary embedding $j:V \rightarrow M$ with critical point $\kappa$ such that $\kappa < \tau < j(\kappa) < j(\tau)$ and $M^{j(\tau)} \subseteq M$.
Nov
6
awarded  Yearling
Nov
5
answered A Special Pair of Models for ZFC (New Version)
Oct
28
accepted Square and stationary reflection
Oct
28
comment Square and stationary reflection
Yes, a Harrington-Shelah style forcing construction works for every regular, uncountable $\kappa$. In fact, it can be shown that, in the generic extension, we have a $\square(\kappa^+)$ sequence whose clubs avoid a stationary subset of $S^{\kappa^+}_\kappa$. I'm not sure about the situation for singular $\kappa$, though.
May
26
awarded  Enthusiast
Jan
31
awarded  Scholar
Jan
31
accepted Existence of scales with special properties
Jan
30
answered Existence of scales with special properties
Jan
23
comment Existence of scales with special properties
Also, re."having a small cofinally interleaved sequence implies that it holds", are you talking about a sequence cofinally interleaved with the entire scale or with an initial segment of the scale? In either case, I don't see how such a sequence contradicts the failure of my property. It seems quite possible that there is a small cofinally interleaved family and $\kappa$-many $\alpha$ such that $f_\alpha <_i f_\beta$. For example, a member of this cofinally interleaved family could be $<^*$-above $\kappa$-many of the relevant $f_\alpha$s.