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Update of tests to compile with the sRNG addition.

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Audited the code conventions (again) with the CPS momentum denominator
and added anti periodic in time to the Test_mobius_force.cc and
tested the Test_dwf_gpforce.

Promoted thesee to test full HMC hamiltonian, tr P^2/2 + phidag MdagM phi

with the same pdot and Udot as audited in the Integrator.h etc...

With full comments and sources for factors.
This commit is contained in:
Peter Boyle
2021-03-18 09:10:02 -04:00
parent 9c2b37218a
commit 49b0af2c95
7 changed files with 188 additions and 60 deletions
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109
tests/forces/Test_mobius_force.cc
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@ -69,7 +69,14 @@ int main (int argc, char ** argv)
RealD M5=1.8;
RealD b=0.5;
RealD c=0.5;
MobiusFermionR Ddwf(U,*FGrid,*FrbGrid,*UGrid,*UrbGrid,mass,M5,b,c);
WilsonImplParams p;
p.boundary_phases[0] = 1.0;
p.boundary_phases[1] = 1.0;
p.boundary_phases[2] = 1.0;
p.boundary_phases[3] =- 1.0;
MobiusFermionR Ddwf(U,*FGrid,*FrbGrid,*UGrid,*UrbGrid,mass,M5,b,c,p);
Ddwf.M (phi,Mphi);
ComplexD S = innerProduct(Mphi,Mphi); // pdag MdagM p
@ -82,24 +89,44 @@ int main (int argc, char ** argv)
Ddwf.MDeriv(tmp , Mphi, phi,DaggerNo ); UdSdU=tmp;
Ddwf.MDeriv(tmp , phi, Mphi,DaggerYes ); UdSdU=(UdSdU+tmp);
// *****************************************************************************************
// *** There is a funny negative sign in all derivatives. This is - UdSdU. ***
// *** ***
// *** Deriv in both Wilson gauge action and the TwoFlavour.h seems to miss a minus sign ***
// *** UdSdU is negated relative to what I think - call what is returned mUdSdU, ***
// *** and insert minus sign ***
// *****************************************************************************************
UdSdU = - UdSdU ; // Follow sign convention of actions in Grid. Seems crazy.
LatticeFermion Ftmp (FGrid);
////////////////////////////////////
// Modify the gauge field a little
////////////////////////////////////
RealD dt = 0.0001;
RealD dt = 0.001;
RealD Hmom = 0.0;
RealD Hmomprime = 0.0;
LatticeColourMatrix mommu(UGrid);
LatticeColourMatrix forcemu(UGrid);
LatticeColourMatrix mUdSdUmu(UGrid);
LatticeGaugeField mom(UGrid);
LatticeGaugeField Uprime(UGrid);
for(int mu=0;mu<Nd;mu++){
SU<Nc>::GaussianFundamentalLieAlgebraMatrix(RNG4, mommu); // Traceless antihermitian momentum; gaussian in lie alg
PokeIndex<LorentzIndex>(mom,mommu,mu);
// Momentum Hamiltonian is - trace(p^2)/HMC_MOM_DENOMINATOR
//
// Integrator.h: RealD H = - FieldImplementation::FieldSquareNorm(P)/HMC_MOMENTUM_DENOMINATOR; // - trace (P*P)/denom // GaugeImplTypes.h: Hloc += trace(Pmu * Pmu);
// Sign comes from a sneaky multiply by "i" in GaussianFundemantalLie algebra
// P is i P^a_\mu T^a, not Pa Ta
//
// Integrator.h: H = Hmom + sum S(action)
Hmom -= real(sum(trace(mommu*mommu)))/ HMC_MOMENTUM_DENOMINATOR;
// fourth order exponential approx
autoView( U_v , U, CpuRead);
autoView( mom_v, mom, CpuRead);
@ -115,6 +142,7 @@ int main (int argc, char ** argv)
;
});
}
std::cout << GridLogMessage <<"Initial mom hamiltonian is "<< Hmom <<std::endl;
Ddwf.ImportGauge(Uprime);
Ddwf.M (phi,MphiPrime);
@ -125,32 +153,87 @@ int main (int argc, char ** argv)
// Use derivative to estimate dS
//////////////////////////////////////////////
LatticeComplex dS(UGrid); dS = Zero();
LatticeComplex dSmom(UGrid); dSmom = Zero();
LatticeComplex dSmom2(UGrid); dSmom2 = Zero();
for(int mu=0;mu<Nd;mu++){
mommu = PeekIndex<LorentzIndex>(UdSdU,mu);
mommu=Ta(mommu)*2.0;
mommu=Ta(mommu);
PokeIndex<LorentzIndex>(UdSdU,mommu,mu);
}
for(int mu=0;mu<Nd;mu++){
forcemu = PeekIndex<LorentzIndex>(UdSdU,mu);
mUdSdUmu= PeekIndex<LorentzIndex>(UdSdU,mu);
mommu = PeekIndex<LorentzIndex>(mom,mu);
// Update PF action density
dS = dS+trace(mommu*forcemu)*dt;
//
// Derive HMC eom:
//
// Sdot = - 2 trace( p p^dot ) / D - trace( p [ mUdSdU - h.c. ] ) = 0
//
//
// Sdot = 0 = - 2 trace( p p^dot ) / D - 2 trace( p Ta( mUdSdU ) = 0
//
// EOM:
//
// pdot = - D Ta( mUdSdU ) -- source of sign is the "funny sign" above
//
// dSqcd_dt = - 2.0*trace(mommu* Ta(mUdSdU) )*dt -- i.e. mUdSdU with adjoint term -> force has a 2x implicit
//
// dH_mom/dt = - 2 trace (p pdot)/Denom
//
// dH_tot / dt = 0 <= pdot = - Denom * mUdSdU
//
// dH_mom/dt = 2 trace (p mUdSdU )
//
// True Momentum delta H has a dt^2 piece
//
// dSmom = [ trace mom*mom - trace ( (mom-Denom*f*dt)(mom-Denom*f*dt) ) ] / Denom
// = 2*trace(mom*f) dt - Denom*dt*dt * trace(f*f).
// = dSmom + dSmom2
//
dS = dS - 2.0*trace(mommu*mUdSdUmu)*dt; // U and Udagger derivs hence 2x.
dSmom = dSmom + 2.0*trace(mommu*mUdSdUmu) * dt; // this 2.0 coms from derivative of p^2
dSmom2 = dSmom2 - trace(mUdSdUmu*mUdSdUmu) * dt*dt* HMC_MOMENTUM_DENOMINATOR; // Remnant
mommu = mommu - mUdSdUmu * dt* HMC_MOMENTUM_DENOMINATOR;;
Hmomprime -= real(sum(trace(mommu*mommu))) / HMC_MOMENTUM_DENOMINATOR;
}
ComplexD dSpred = sum(dS);
ComplexD dSm = sum(dSmom);
ComplexD dSm2 = sum(dSmom2);
std::cout << GridLogMessage << " -- S "<<S<<std::endl;
std::cout << GridLogMessage << " -- Sprime "<<Sprime<<std::endl;
std::cout << GridLogMessage << "dS "<<Sprime-S<<std::endl;
std::cout << GridLogMessage << "predict dS "<< dSpred <<std::endl;
std::cout << GridLogMessage <<"dSm "<< dSm<<std::endl;
std::cout << GridLogMessage <<"dSm2 "<< dSm2<<std::endl;
std::cout << GridLogMessage <<"Initial mom hamiltonian is "<< Hmom <<std::endl;
std::cout << GridLogMessage <<"Final mom hamiltonian is "<< Hmomprime <<std::endl;
std::cout << GridLogMessage <<"Delta mom hamiltonian is "<< Hmomprime-Hmom <<std::endl;
std::cout << GridLogMessage <<"predict Delta mom hamiltonian is "<< dSm+dSm2 <<std::endl;
std::cout << GridLogMessage << "Initial S "<<S<<std::endl;
std::cout << GridLogMessage << "Final S "<<Sprime<<std::endl;
std::cout << GridLogMessage << "Delta S "<<Sprime-S<<std::endl;
std::cout << GridLogMessage << "predict delta S"<< dSpred <<std::endl;
std::cout << GridLogMessage << "defect "<< Sprime-S-dSpred <<std::endl;
std::cout << GridLogMessage << "Total dS "<< Hmomprime - Hmom + Sprime - S <<std::endl;
std::cout << GridLogMessage << "dS - dt^2 term "<< Hmomprime - Hmom + Sprime - S - dSm2 <<std::endl;
assert( fabs(real(Sprime-S-dSpred)) < 1.0 ) ;
std::cout<< GridLogMessage << "Done" <<std::endl;
Grid_finalize();
}