I am used to being called a mezalzel b’chvod chachomim, and I can handle that. But this time, I in no way was referring to the Mechaber, nor do I think his position is ridiculous or logically untenable.
My understanding of the Mechaber is totally different.The mechaber states, ?????? ?????? ???? ???? ???? ?? ????
Those are the words. Whereas you are interpreting shkias hachamah to mean sunset, I do not. I already showed how Rabbeinu Tam postulated two different shkiot hachamah, when neither of them referred to sunset.
Furthermore, if the Mechaber understood like you, all he had to say was , ???? ????? ????? and we would all yell, Of course! Sunset!. But no, he talks about a hatchalah. What hatchalah? The sun sets and it’s gone! Beginning and end within a minute or two! Second, why the explanation ???? ???? ???? ?? ???? ? Any child can see that after the sun sets it is no longer seen on the land!
The answer is that the Mechaber is not talking about the sun setting, but rather the point in time, way before the sun sets, where it’s light does not shine brightly on the earth ??? ???? ???? ?? ????, where it’s effectiveness is very muted, but before it sets. This is hatchalat hashkiah, and is exactly the way I (not me, but the sources I mentioned) explained Rabbeinu Tam. This period is 3.25 mil and is still vadai yom. Bein hashmashot is after this period, some time after the sun sets, and is only 0.75 mil. How are these periods related to sunset? They are not related. Bein hashmashot is simply 0.75 mil before three stars. Tchilat shkiah is 4 mil before three stars. The Mechaber holds like Rabbeinu Tam, but not the Satmar version. That is pshat, and it answers all problems, at least according to Rabbeinu Tam.
Again, according to this line of reasoning, Rabbenu Tam’s tzet is three stars, just like everyone else. I reiterate, calling darkness vadai yom is ridiculous and logically untenable. Neither Rabbeinu Tam nor the Mechaber hold that darkness is day.
To Sam the Scholar and Anav, I hope this explanation helped to understand the Mechaber and Rabbeinu Tam.