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Would appreciate any help on the following in mathematica I cant figure it out. I have a system of equations that I am trying to solve symbolically. I have 9 equations and 8 unknowns (I have also tried a version of this with 6 equations and 6 unknowns with same result :(
Note this is after I had quit all applications and had mathematica running alone for about 20hours.
No more memory available. Mathematica kernel has shut down. Try quitting other applications and then retry. Below I am showing the version with 6eqns and 6 unknowns

(*setting these to reduce equations to 6 equations and 6 unknowns*)
Subscript[b, 11] = 1;
Subscript[b, 21] = 0;

y11 = (Subscript[a, 11] *Subscript[b, 11]) - (Subscript[a, 21]* 
 Subscript[b, 21]) ;
y21 = (Subscript[a, 21] *Subscript[b, 11]) + (Subscript[a, 11]* 
 Subscript[b, 21]);

y13 = ((Subscript[K, 1 R]*Subscript[a, 11]) *
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(3\)]\)) + (Subscript[a, 11]
  Subscript[b, 13]) - ((Subscript[K, 1 L]*Subscript[a, 21])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) *Subscript[b, 
 21]) + ((Subscript[K, 1 R]*Subscript[a, 11])* Subscript[b, 11] 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) - ((Subscript[K, 
   1 L]*Subscript[a, 21])* 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(3\)]\)) - (Subscript[a, 21]
  Subscript[b, 23]);
y23 = ((Subscript[K, 1 L]*Subscript[a, 21])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(3\)]\)) + (Subscript[a, 21]
  Subscript[b, 13]) + ((Subscript[K, 1 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) Subscript[b, 
 21]) + ((Subscript[K, 1 L]*Subscript[a, 21])* Subscript[b, 11] 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) + ((Subscript[K, 
   1 R]*Subscript[a, 11]) *
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(3\)]\)) + (Subscript[a, 11]
  Subscript[b, 23]);

y15 = ((Subscript[K, 2 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(5\)]\)) + (3 *(Subscript[K, 
   1 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) Subscript[b, 
 13]) + (Subscript[a, 11] Subscript[b, 
 15]) - ((Subscript[K, 2 L]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(4\)]\) Subscript[b, 
 21]) - (2 *(Subscript[K, 1 L]*Subscript[a, 21])* Subscript[b, 11]
  Subscript[b, 13] Subscript[b, 
 21]) + (2 *(Subscript[K, 2 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(3\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) + ((Subscript[K, 
   1 R]*Subscript[a, 11])* Subscript[b, 13] 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) - (2 *(Subscript[K, 
   2 L]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(3\)]\)) + ((Subscript[K, 
   2 R]*Subscript[a, 11])* Subscript[b, 11] 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(4\)]\)) - ((Subscript[K, 
   2 L]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(5\)]\)) - ((Subscript[K, 
   1 L]*Subscript[a, 21])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) Subscript[b, 
 23]) - (2 *(Subscript[K, 1 R]*Subscript[a, 11])* Subscript[b, 11]
  Subscript[b, 21] Subscript[b, 
 23]) + ((Subscript[K, 1 L]*Subscript[a, 21])* 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\) Subscript[b, 
 23]) - (Subscript[a, 21] Subscript[b, 25]);
y25 = ((Subscript[K, 2 L]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(5\)]\)) + (3* (Subscript[K, 
   1 L]*Subscript[a, 21])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) Subscript[b, 
 13]) + (Subscript[a, 21] Subscript[b, 
 15]) + ((Subscript[K, 2 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(4\)]\) Subscript[b, 
 21]) + (2 * (Subscript[K, 1 R]*Subscript[a, 11])* Subscript[b, 
 11] Subscript[b, 13] Subscript[b, 
 21]) - (2*(Subscript[K, 2 L]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(3\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) + ((Subscript[K, 
   1 L]*Subscript[a, 21])* Subscript[b, 13] 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) + (2  *(Subscript[K, 
   2 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(3\)]\)) + ((Subscript[K, 
   2 L]*Subscript[a, 11])* Subscript[b, 11] 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(4\)]\)) + ((Subscript[K, 
   2 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(5\)]\)) - ((Subscript[K, 
   2 L]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(5\)]\)) + ((Subscript[K, 
   1 R]*Subscript[a, 11])*
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) Subscript[b, 
 23]) - (2 * (Subscript[K, 1 L]*Subscript[a, 21])* Subscript[b, 
 11] Subscript[b, 21] Subscript[b, 
 23]) - ((Subscript[K, 1 R]*Subscript[a, 11])* 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\) Subscript[b, 
 23]) + (Subscript[a, 11] Subscript[b, 25]);

h11 = A1*y11 + ((3/4)*(A1)^3*y13) + ((5/8)*(A1)^5*y15) + 
I*(A1*y21 + ((3/4)*(A1)^3*y23) + ((5/8)*(A1)^5*y25));

h31 = ((A1^3)/4)*y13 + ((5/16)*(A1)^5*y15) + 
I*(((A1^3)/4)*y23 + ((5/16)*(A1)^5*y25));

h51 = ((A1^5)/16)*y15 + I*((A1^5/16)*y25);

h12 = A2*y11 + ((3/4)*(A2)^3*y13) + ((5/8)*(A2)^5*y15) + 
I*(A2*y21 + ((3/4)*(A2)^3*y23) + ((5/8)*(A2)^5*y25));

h32 = ((A2^3)/4)*y13 + ((5/16)*(A2)^5*y15) + 
I*(((A2^3)/4)*y23 + ((5/16)*(A2)^5*y25));

h52 = ((A2^5)/16)*y15 + I*((A2^5/16)*y25);


h11g = Expand[(A1*
    y11 + ((3/4)*(A1)^3*y13) + ((5/8)*(A1)^5*y15))^2 + (A1*
    y21 + ((3/4)*(A1)^3*y23) + ((5/8)*(A1)^5*y25))^2];
h12g = Expand[(A2*
    y11 + ((3/4)*(A2)^3*y13) + ((5/8)*(A2)^5*y15))^2 + (A2*
    y21 + ((3/4)*(A2)^3*y23) + ((5/8)*(A2)^5*y25))^2];
h31g = Expand[(((A1^3)/4)*
    y13 + ((5/16)*(A1)^5*y15))^2 + (((A1^3)/4)*
    y23 + ((5/16)*(A1)^5*y25))^2];
h32g = Expand[(((A2^3)/4)*
    y13 + ((5/16)*(A2)^5*y15))^2 + (((A2^3)/4)*
    y23 + ((5/16)*(A2)^5*y25))^2];
h51g = Expand[(((A1^5)/16)*y15)^2 + ((A1^5/16)*y25)^2];
h52g = Expand[(((A2^5)/16)*y15)^2 + ((A2^5/16)*y25)^2];


Solve[{h11g - (A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(11\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) + A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(21\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) + A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(11\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\) + A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(21\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) == 0,
h12g - (A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(11\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) + A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(21\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(11\), \(2\)]\) + A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(11\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\) + A1^2 
\!\(\*SubsuperscriptBox[\(a\), \(21\), \(2\)]\) 
\!\(\*SubsuperscriptBox[\(b\), \(21\), \(2\)]\)) == 0,
h31g == 0, h32g == 0, h51g == 0, h52g == 0}, {Subscript[a, 
11], Subscript[a, 21], Subscript[b, 13], Subscript[b, 23], 
Subscript[b, 15], Subscript[b, 25]}]
share|improve this question

migrated from scicomp.stackexchange.com Sep 4 '13 at 16:48

This question came from our site for scientists using computers to solve scientific problems.

    
Yes please go ahead and migrate the question there. –  user5087 Sep 4 '13 at 7:06
1  
Welcome to the site. If you could just add the code of the equations you are running someone might be able to help you. At the moment only God knows what the problem could be, and he is not registered at Mathematica.SE. –  István Zachar Sep 5 '13 at 8:23

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