My brain hurts, but;
The first one is actually a spiral.
Second and third one are possible.
Gradient magic is also a lie.
-At this point I'm wondering why I'm still doing the others.
Okay, these are all fakes. Nice one though Imp
I wonder if you put this on Facebook or another stupid social medium how many people would actually like and believe this.
The first one, as Mave said, are spirals...
The second one is possible, but the actual illusion is not.
The third one is easily possible, but again the actual illusion isn't.
The gradient is fake.
The arrows aren't, that's a proper optical illusion.
And I can't tell the circles one, but looks fake.