I've been having these freaky experiences recently where out of the corner of the eye, I spot my cat or hear my cat coming down the stairs. But she's not there. And she's a live. But when she's not in the house, I keeping thinking I see her doing the things she commonly does.
Time warp, OP. Very common for cats, disconcerting for us because we're not used to it.
Ge rid of the yellow wallpaper, OP.
Time warp? LOL! What utter bullshit. You're joking, right? Time travel is not possible.
This is clearly inter-dimensional phenomena, OP. Tread carefully.
She's Gaslighting you, OP. Is she in the will?
My cat does that - she's not there, and then she is there, in the blink of an eye. Masters at stealth. But it sounds more like she's in your head, OP, and making you think thoughts about her.
Btw, there is a theory that cats actually think they can make themselves invisible. They can't, of course, but they think they can, which leads them to master skills that even a trained ninja couldn't accomplish.