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4h

comment 
Namba forcing and semiproperness
Thank you very much for closing this loop! 
4h

accepted  Namba forcing and semiproperness 
Apr
13 
answered  Can There be RudinKeisler Immediate Sucessors? 
Jan
7 
answered  Can Sacks forcing add a Cohen generic real over $L$? 
Jan
5 
comment 
Forcing the negation of CH without adding Cohen reals over L
Does this work if the ground model is something other than L? Can Sacks forcing over a model of CH containing no LCohen reals add an LCohen real? 
Dec
14 
awarded  Custodian 
Nov
17 
awarded  Popular Question 
Nov
13 
accepted  Clubguessing at $\omega_2$ 
Nov
13 
comment 
Clubguessing at $\omega_2$
Nice! This is exactly what I needed. 
Nov
13 
asked  Clubguessing at $\omega_2$ 
Nov
8 
answered  Is there a modification of Martin's Axiom which admits nonmeasurable sets of size less than continuum? 
Oct
30 
comment 
PCF conjecture and fixed points of the $\aleph$function
Mohammed, do you know off hand if the cardinal involved can be the least fixed point? 
Oct
29 
comment 
PCF conjecture and fixed points of the $\aleph$function
That would be a huge advance for sure, and much more difficult! 
Oct
21 
comment 
The cofinality of $(\mathbb{N}^\kappa,\le)$ for uncountable $\kappa$?
@BoazTsaban: Jech's Chapter 29 mentions that the question of whether $f(\aleph_1)<2^{\aleph_1}$ is consistent is open, and I seem to recall that the question was also mentioned in the original "green version" of his book from 1978. 
Oct
18 
comment 
The cofinality of $(\mathbb{N}^\kappa,\le)$ for uncountable $\kappa$?
Should have said "stronger implication" as the assumption is weaker... 
Oct
18 
comment 
The cofinality of $(\mathbb{N}^\kappa,\le)$ for uncountable $\kappa$?
Just observe that the cofinality of $([\aleph_1]^{\aleph_0},\subseteq)$ is $\aleph_1$, as witnessed by initial segments. Same holds for all the $\aleph_n$ by induction. 
Oct
18 
comment 
The cofinality of $(\mathbb{N}^\kappa,\le)$ for uncountable $\kappa$?
If the weakened implication in (2) holds then we would have $f(\aleph_1)=2^{\aleph_1}$ in ZFC. 
Oct
16 
comment 
$\kappa$support iterations of $<\kappa$strategically closed forcing
That would indeed be silly: the result is folklore, and they include in a section recalling some standard facts. They prove the result for the same reason I asked for a reference: we need that the canonical strategy has some nice properties, and it is convenient to have a place to send a reader wanting to see some details. 
Oct
15 
answered  $\kappa$support iterations of $<\kappa$strategically closed forcing 
Oct
1 
comment 
$\kappa$support iterations of $<\kappa$strategically closed forcing
Sure. I was hoping to just be able to point somewhere if it were already written up. 