# String Theory questions. (1 Viewer)

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#### lowing99

Hi

In string theory, as I understand it, a frequency between two points creates a particle, different frequencies make different particles.

If say the points were arranged in a cube there would be 8 points with twelve strings between them, would this lead to twelve particles or would one particle be produced from the harmonic frequency of the entire cube?

Second question, what is the explanation for the points, are they just an imaginary point at the end of each string or do they have attractive or repulsive effects? Is the frequency of the string a product of say a + value at one end and a - value at the other?

Last question, If the strings are one dimensional would the cube described above be 3 dimensional?

Hope somene can help

Best

Colin

#### Kevin_Axion

Yes, the cube would be 3-dimensional, as the edges of a cube are one-dimensional objects in a 3-dimensional space. Your idea of strings being coupled into a cubic shape isn't really physical. This isn't how things interact in the physical world. But if you could describe a structure such as a exotic quark in such a way it would be the product of individual particles appearing as one because the colour charges cancel out and other quantities which make it appear as a point particle.

#### lowing99

Yes, the cube would be 3-dimensional, as the edges of a cube are one-dimensional objects in a 3-dimensional space. Your idea of strings being coupled into a cubic shape isn't really physical. This isn't how things interact in the physical world. But if you could describe a structure such as a exotic quark in such a way it would be the product of individual particles appearing as one because the colour charges cancel out and other quantities which make it appear as a point particle.
Hi Kevin

Thanks for the post, the cube above is a purely theoretical shape I needed some kind of structure to form the question.

Could you clarify further, do you mean that the point particle would be in effect the product of the frequencies within the cube (i.e. producing a larger or smaller freq), or do you mean the single or multiple harmonics of all twelve frequencies make the point particle.

Did you have any answer to the +- question, or is that way out :)

Thanks for the 3d bit I can tick that off the list now.

Best

Colin

#### Kevin_Axion

The frequencies of the string determine the properties of particles. For instance the amount of harmonic partials along the string determine the energy and also its mass, mass-energy equivalence. The 'rotation' of the string determines its spin, the charge, other fundamental properties of the string are determined by these attributes, such as colour charge - quarks and gluons. What I'm saying is that the coupling of quarks that are confined by Asymptotic Freedom (Asymptotic Freedom is an idea predicted by QCD and says that quarks and gluons interact and as the distance increases the force diverges. Therefore since quarks are close they appear to be free particles within the Hadrons/Mesons) create a particle such as a proton in which the charges cancel out to appear to create another particle. In a proton the colour charge is neutral because the quark colour charges cancel out. Where as the electric charge doesn't cancel because a proton is $$up$$$$+$$$$up$$$$+$$$$down$$, and an up quark has a charge of $$\frac{2}{3}$$ and a down quark has a charge of $$-\frac{1}{3}$$therefore this creates a total charge of $$\frac{3}{3}$$ or $$1$$. Alike, the strings will cancel out in the cubic shape to create another particle like a proton or exotic particles in which the properties cancel and couple in a fashion that appears to be another particle. About the end points. I think you're talking about D0-Branes.

#### lowing99

Thanks Kevin

I'm new to the quantum world. I'm going to have to do some reading on quantum particles. I'll try and find some threads on D0-Branes.

best

Colin

#### Kevin_Axion

You should private message someone on this forum by the name of surprised. He's a string theorist so he'd be able to help you.

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