Hi,

One more question regarding the implementation.

Isn't it better to check if the reconnection move is feasible? (same like the close/open move in which IRA and MASHA should be on the same site).
I understand that the ALPS implementation keeps the jump and reconnection process symmetric. But essentially they are not because a regular jump (where the kink is inserted before MASHA) is always possible unlike the reconnection process.
Is there is something I missing?

Thanks again for the assistance.

snir

On Wed, Dec 30, 2009 at 11:31 AM, Snir Gazit <snirgaz@tx.technion.ac.il> wrote:

Thanks for the quick and helpful reply!

Snir

On Wed, Dec 30, 2009 at 11:24 AM, Matthias Troyer <troyer@phys.ethz.ch> wrote:

On 30 Dec 2009, at 10:08, Snir Gazit wrote:

> Hi,
>
> I am implementing the worm algorithm for the Bose Hubbard model.
> On of the "worm moves" is to insert a kink after the MASHA head this can cause a reconnection of the worm.
> I think that this move is possible only when there is a world line in the target site, other wise there is nothing to connect to.
> I tried to see were this condition is implement in the code but I failed to find it.
> I'll be grateful if someone can direct me to the location of this condition in the code, or tell me were my reasoning is wrong (may be there is some other way to close the world line).
>
> Thanks in advance
>
> Snir

We calculate the matrix element for the proposed insertion. In the case you mention the matrix element is 0, and the proposed update is rejected immediately.

Matthias