portelli/Grid
1
0
Fork 0
mirror of https://github.com/paboyle/Grid.git synced 2024-11-10 07:55:35 +00:00
Code Releases Activity

Default tau spacing should be longer c.f. Zbigniew Srocinsky thesis

Browse Source
This commit is contained in:
Peter Boyle 2019-02-24 14:43:22 +00:00
parent 196c9e4a4a
commit 048397d880
2 changed files with 24 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
Grid/qcd/action/gauge/GaugeImplTypes.h
View File

@ -87,12 +87,32 @@ public:
/////////////////////////////////////////////////////////// ///////////////////////////////////////////////////////////
// Move these to another class // Move these to another class
// HMC auxiliary functions // HMC auxiliary functions
static inline void generate_momenta(Field &P, GridParallelRNG &pRNG) { static inline void generate_momenta(Field &P, GridParallelRNG &pRNG)
// specific for SU gauge fields {
// Zbigniew Srocinsky thesis:
//
// P(p) = N \Prod_{x\mu}e^-{1/2 Tr (p^2_mux)}
//
// p_x,mu = c_x,mu,a T_a
//
// Tr p^2 = sum_a,x,mu 1/2 (c_x,mu,a)^2
//
// Which implies P(p) = N \Prod_{x,\mu,a} e^-{1/4 c_xmua^2 }
//
// = N \Prod_{x,\mu,a} e^-{1/2 (c_xmua/sqrt{2})^2 }
//
// Expect c' = cxmua/sqrt(2) to be a unit variance gaussian.
//
// Expect cxmua variance sqrt(2).
//
// Must scale the momentum by sqrt(2) up to invoke CPS and UKQCD conventions
//
LinkField Pmu(P._grid); LinkField Pmu(P._grid);
Pmu = zero; Pmu = Zero();
for (int mu = 0; mu < Nd; mu++) { for (int mu = 0; mu < Nd; mu++) {
SU<Nrepresentation>::GaussianFundamentalLieAlgebraMatrix(pRNG, Pmu); SU<Nrepresentation>::GaussianFundamentalLieAlgebraMatrix(pRNG, Pmu);
RealD scale = ::sqrt(2) ;
Pmu = Pmu*scale;
PokeIndex<LorentzIndex>(P, Pmu, mu); PokeIndex<LorentzIndex>(P, Pmu, mu);
} }
} }

2
Grid/qcd/action/gauge/PlaqPlusRectangleAction.h
View File

@ -75,7 +75,7 @@ namespace Grid{
virtual void deriv(const GaugeField &Umu,GaugeField & dSdU) { virtual void deriv(const GaugeField &Umu,GaugeField & dSdU) {
//extend Ta to include Lorentz indexes //extend Ta to include Lorentz indexes
RealD factor_p = c_plaq/RealD(Nc)*0.5; RealD factor_p = c_plaq/RealD(Nc)*0.5;
RealD factor_r = c_rect/RealD(Nc)*0.5; RealD factor_r = c_rect/RealD(Nc)*0.5;
GridBase *grid = Umu._grid; GridBase *grid = Umu._grid;