I am just choosing a branch , I am not destroying the branch in wich I choose not to sign up.
Actually… you are. The physical implementation of making the choice involves shifting weight from not-signed-up branches to signed-up branches (note, the ‘not-signed-up-yet’ branch is defined in a way that lets it leak amplitude). That implementation is contained within you, and it involves processes we describe as applying operators on that branch which reduce its amplitude. This totally counts as destroying the branch.
If you sign up for cryonics at time T1, then the not-signed-up branch has lower amplitude after T1 than it had before T1. But this is very different from saying that the not-signed up branch has lower amplitude after T1 than it would have had after T1 if you had not signed up for cryonics at T1. In fact, the latter statement is necessarily false if physics really is timeless.
I think this latter point is what the other posters are driving at. It is true that if there is a branch at T1 where some yous go down a path where they sign up and others don’t, then the amplitude for not-signed-up is lower after T1. But this happens even if this particular you doesn’t go down the signed-up branch. What matters is that the branch point occurs, not which one any specific you takes.
In other words, amplitude is always being seeped from the not-signed-up branch, even if some particular you keeps not leaving that branch.
Actually… you are. The physical implementation of making the choice involves shifting weight from not-signed-up branches to signed-up branches (note, the ‘not-signed-up-yet’ branch is defined in a way that lets it leak amplitude). That implementation is contained within you, and it involves processes we describe as applying operators on that branch which reduce its amplitude. This totally counts as destroying the branch.
Okay, we need to be really careful about this.
If you sign up for cryonics at time T1, then the not-signed-up branch has lower amplitude after T1 than it had before T1. But this is very different from saying that the not-signed up branch has lower amplitude after T1 than it would have had after T1 if you had not signed up for cryonics at T1. In fact, the latter statement is necessarily false if physics really is timeless.
I think this latter point is what the other posters are driving at. It is true that if there is a branch at T1 where some yous go down a path where they sign up and others don’t, then the amplitude for not-signed-up is lower after T1. But this happens even if this particular you doesn’t go down the signed-up branch. What matters is that the branch point occurs, not which one any specific you takes.
In other words, amplitude is always being seeped from the not-signed-up branch, even if some particular you keeps not leaving that branch.