I was with my aunt in a domed white building. Apparently we were in Rome, and the building was Catholic (at some point I had a little a-ha! moment when I realized it was Roman Catholic, though I'm not sure whether the Roman or the Catholic was the revelation). The interior was completely white, and benches of some sort wrapped the entire perimeter of the building, essentially floor to ceiling. Other people were also touring the building, and when I looked up I saw that people appeared to be walking, in some sort of gravity-defying illusion, on the ceiling. This was somehow explained, in bizarre dream-logic, by the fact that although we generally think of gravity as merely "down," it of course refers to the pull of a smaller object toward a much more massive one.
I totally wanted to climb on the ceiling, so my aunt and I went out to a narrow passageway where there was a staircase with a red wooden banister. At first it was easy to climb the stairs, but then I felt a strong pull back down the stairs, like I was losing my balance and the stairs were being pulled out from under me. It was a very unpleasant, vertiginous feeling, and I realized I just didn't have the fortitude to climb on the ceiling.
So we sort of slid back down the stairs, holding on to the banister, and then went outside to continue our tour of Rome.
Later I dreamed that there was a cute little boy in a highchair, who was rocking back and forth so that if I hadn't stepped in and caught him, he would have fallen over backward. He pointed down and said "Floor!" so I undid his little safety belt so that he could play on the floor. Then I noticed that Barack Obama was giving some sort of speech in the other corner of the room. He left, and I knew that he was going to come back in the entrance right beside us. He did, and I said to the little boy, "There he is!" and he waved at us.