What are Strings made of???

[AntonioLao]

membranes are two-dimensional equivalent of strings postulated by Michael Duff of Texas A&M University in the late 1980's.

[Guille]

Antonio Lao,

Maybe you misunderstood my question..........

What are membranes made of??

Or are membranes compeltely fundamental?

[AntonioLao]

one-dimensional strings are made of energy whose modes of vibrations are constraint to two degrees of freedom. But for two-dimensional strings (membranes), their vibrational modes have an infinite degrees of freedom in an infinitely extended 2D plane. In cylindrical surfaces, spherical surfaces, and many other curvilinear closed surfaces, the degrees of freedom are finite. But the spherical surface, which is a closed membrane has the optimal Lagrangian at absolute minimum. Lagrangian is the difference between kinetic and potential energy. When these two energy functions are equal then and only then is the Lagrangian equal to zero.

[Guille]

What defines the Langrangian??

[AntonioLao]

Lagrangian (L) is the different between kinetic energy (T) and potential energy (V)

[math] L = T - V [/math]

the Hamiltonian is the sum of T and V.

[math] H = T + V [/math]

[dipayankar]

Antonio;
Hence does it mean that membranes are actually infinite number of strings 'amalgamated' together?? If yes then their individulity would be lost (rather like atoms in a molecule). So does strings actually exist in their individual capacity?

[AntonioLao]

dipayankar
In mathematics, we are allowed to take slices of n-dimensional spacetime for analysis. So, if we cut a slice of a membrane the cross-section appears as a 1D string embedded in higher dimensional spacetime. The looker is always at a higher dimension than the lookee.

[Guille]

Lagrangian (L) is the different between kinetic energy (T) and potential energy (V)

[math] L = T - V [/math]

the Hamiltonian is the sum of T and V.

[math] H = T + V [/math]

Does this mean something...........


T*V=????

or

T/V=???

or

V/T=???

I don't think so, but I'm not sure.

[AntonioLao]

Does this mean something...........
T*V=???? or T/V=??? or V/T=???
I don't think so, but I'm not sure.

the 1st is the square of energy very similar to my quantized space theory
the 2nd and 3rd ar both dimensionless ratio of energies. But a dimensional ratio of electric field and magnetic field is the speed of something.

[math]\mathbf{v}=\frac{\mathbf{E}}{\mathbf{B}}[/math]

but vector division still is undefined in mathematics.

[Guille]

I want to post that I have been thinking about what strings are made of, and...

I've concluded that I can't simply imagen something to be conpletely fundamental. Try to think about it, something that isn't made up of smaller things? I can't think about it as a fisical thing.