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Sunday, August 3, 2014

What Thermal Gravity? Too Hot To Handle...

From the post "Heat Wave"

Tt=xgT3T3t

T=xgT3T3tt

T(t)T(x)=xgT(2Tt2+C(x)+C) ---(*)

where C(x) is a function only in x and C is a numerical constant.

If we insist that T propagate as a wave at velocity v,

2Tt2=v22Tx2

Substitute the above into (*)

T(t)T(x)=xgT(v22Tx2+C(x)+C)

when we let T=T(t)T(x).

If  T(t) has no constant term,

C(x)=C=0,

T(t)T(x)=v2xgTT(t)d2T(x)dx2

gT=v2xT(x)d2T(x)dx2

The biggest assumption here is that T propagate as a wave at velocity v.  We know that gT0   as  x.    Thermal gravity is positive, and points away from higher temperature.  It is in the same direction as x.  T(x) as a product with T(t) satisfies the wave equation.  Just on the boundary of the hot spot, gT is maximum.   Thereafter,  gT   decreases monotonously.

Still looking for gT(x)...

Because the immediate answer is,

 T(x)=eAx

where

A=1vgTL

which leads right back to

gT=v2x(1vgTL)2

gT=xgTL

x=L

which is undeniable.  Very Hot...