limitten.mws

limitten.mws

The special case v(theta)=-1 , with constraints,

Notation diff(v(thtea),theta$n)=v[n]

>    restart:

the following substitution is made.

>    P(t,theta) = P[infinity](theta)-v(theta)*ln(t)+1/4*exp(P[infinity](theta))^2*diff(Q[infinity](theta),`$`(theta,2))^2*t^2*ln(t)^2+V[1](theta)*t^2+(exp(2*P[infinity](theta))*psi[Q](theta)*diff(Q[infinity](theta),`$`(theta,2))-1/4*diff(Q[infinity](theta),`$`(theta,2))^2-1/4*diff(v(theta),`$`(theta,2)))*t^2*ln(t),Q(t,theta) = Q[infinity](theta)+psi[Q](theta)*t^(2*v(theta))+1/2*diff(Q[infinity](theta),`$`(theta,2))*t^(2*v(theta))*ln(t);

P(t,theta) = P[infinity](theta)-v(theta)*ln(t)+1/4*exp(P[infinity](theta))^2*diff(Q[infinity](theta),`$`(theta,2))^2*t^2*ln(t)^2+V[1](theta)*t^2+(exp(2*P[infinity](theta))*psi[Q](theta)*diff(Q[infinity...

>    grtw();

Scalar invariant library.

Last modified 25 March 1997.

`Differential Invariants`

`Last modified Jan. 20, 1995`

`Basis/tetrad related object definitions`

`Last modified 23 January 2001`

`Last built 27 May, 1999`

`Last built 27 May, 1999`

`GRTensorII Version 1.79 (R4)`

`6 February 2001`

`Developed by Peter Musgrave, Denis Pollney and Kayll Lake`

`Copyright 1994-2001 by the authors.`

`Latest version available from: http://grtensor.phy.queensu.ca/`

`c:/Grtii(6)/Metrics`

>    qload(gowdy);

`Default spacetime` = gowdy

`For the gowdy spacetime:`

Coordinates

x(up)

`x `^a = vector([t, theta, x1, x2])

`Line element`

` ds`^2 = -exp(-1/2*gamma(t,theta))/t^(1/2)*` d`*t^`2 `+exp(-1/2*gamma(t,theta))/t^(1/2)*` d`*theta^`2 `+t*exp(P(t,theta))*` d`*x1^`2 `+2*t*exp(P(t,theta))*Q(t,theta)*` d`*x1^` `*`d `*x2^` `+(t*exp(P(t...

Constraints = [diff(gamma(t,theta),t) = -t*exp(P(t,theta))^2*diff(Q(t,theta),t)^2-t*diff(P(t,theta),t)^2-t*exp(P(t,theta))^2*diff(Q(t,theta),theta)^2-t*diff(P(t,theta),theta)^2, diff(gamma(t,theta),the...
Constraints = [diff(gamma(t,theta),t) = -t*exp(P(t,theta))^2*diff(Q(t,theta),t)^2-t*diff(P(t,theta),t)^2-t*exp(P(t,theta))^2*diff(Q(t,theta),theta)^2-t*diff(P(t,theta),theta)^2, diff(gamma(t,theta),the...

>    grcalc(WeylSq);

`CPU Time ` = .94e-1

>    gralter(_,13,6,7);

Component simplification of a GRTensorII object:

Applying routine `Apply constraints repeatedly` to object WeylSq

Applying routine expand to object WeylSq

Applying routine factor to object WeylSq

`CPU Time ` = .31e-1

>    grmap(_,subs,P(t,theta) = P[infinity](theta)-v(theta)*ln(t)+1/4*exp(P[infinity](theta))^2*diff(Q[infinity](theta),`$`(theta,2))^2*t^2*ln(t)^2+V[1](theta)*t^2+(exp(2*P[infinity](theta))*psi[Q](theta)*diff(Q[infinity](theta),`$`(theta,2))-1/4*diff(Q[infinity](theta),`$`(theta,2))^2-1/4*diff(v(theta),`$`(theta,2)))*t^2*ln(t),Q(t,theta) = Q[infinity](theta)+psi[Q](theta)*t^(2*v(theta))+1/2*diff(Q[infinity](theta),`$`(theta,2))*t^(2*v(theta))*ln(t),`x`);

Applying routine subs to WeylSq

Keep all derivatives of Q[infinity](theta)

>    grmap(_,subs,diff(Q[infinity](theta),theta$4)=Q[4],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(Q[infinity](theta),theta$3)=Q[3],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(Q[infinity](theta),theta)=Q[1],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(Q[infinity](theta),theta$2)=0,`x`);

Applying routine subs to WeylSq

Keep all derivatives of v(theta)

>    grmap(_,subs,diff(v(theta),theta$4)=v[4],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(v(theta),theta$3)=v[3],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(v(theta),theta$2)=v[2],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(v(theta),theta$1)=v[1],`x`):

Applying routine subs to WeylSq

Keep all derivatives of psi[Q](theta)

>    grmap(_,subs,diff(psi[Q](theta),`$`(theta,2))=psi[Q2],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(psi[Q](theta),`$`(theta,3))=psi[Q3],`x`);

Applying routine subs to WeylSq

>    grmap(_,subs,diff(psi[Q](theta),`$`(theta,4))=psi[Q4],`x`);

Applying routine subs to WeylSq

Apply constraints

>    grmap(_,subs,diff(psi[Q](theta),theta)=0,`x`):

Applying routine subs to WeylSq

>    grmap(_,subs,psi[Q](theta)=0,`x`):

Applying routine subs to WeylSq

>    grmap(_,subs,v(theta)=-1,`x`):

Applying routine subs to WeylSq

>    gralter(_,6,7);

Component simplification of a GRTensorII object:

Applying routine expand to object WeylSq

Applying routine factor to object WeylSq

`CPU Time ` = .657

>    denom(grcomponent(WeylSq,[]));

16384*exp(-1/2*gamma(t,theta))^2*t^3

>    factor(subs(t=0,numer(grcomponent(WeylSq,[]))));

-64*exp(P[infinity](theta))^2*exp(0)^2*Q[3]^2*(Q[3]^4*exp(0)^4*exp(P[infinity](theta))^4*ln(0)^6+256*ln(0)^2-256*ln(0)+256-32*Q[3]^2*exp(0)^2*exp(P[infinity](theta))^2*ln(0)^3-96*Q[3]^2*exp(0)^2*exp(P[...

>    core:=limit(factor(t^3*grcomponent(WeylSq,[])/(log(t)^6*exp(gamma(t,theta)))),t=0);

core := -1/256*exp(P[infinity](theta))^6*Q[3]^6

>    Ww:=core*log(t)^6*exp(gamma(t,theta))/t^3;

Ww := -1/256*exp(P[infinity](theta))^6*Q[3]^6*ln(t)^6*exp(gamma(t,theta))/t^3

>    subs(Q[3]=diff(Q[infinity](theta),theta$3),Ww);

-1/256*exp(P[infinity](theta))^6*diff(Q[infinity](theta),`$`(theta,3))^6*ln(t)^6*exp(gamma(t,theta))/t^3

>    latex(%);

-{\frac {1}{256}}\,{\frac { \left( {e^{P_{{\infty }} \left( \theta

 \right) }} \right) ^{6} \left( {\frac {d^{3}}{d{\theta}^{3}}}Q_{{

\infty }} \left( \theta \right)  \right) ^{6} \left( \ln  \left( t

 \right)  \right) ^{6}{e^{\gamma \left( t,\theta \right) }}}{{t}^{3}}}

>