Electromagnetic and weak interaction unification

[ghery]

Hi:

The electromagnetic and weak interactions were unified in what is called the electroweak interaction, but as long as I know they are different classes of interactions, what I mean is that in weak interactions, there are particles that transform in others (like neutron's beta decay) and in electromagnetic interactions, particles repel or are atracted to each other...

If they are so different, how can they be unified ? or is it just that the interactions have almost the same strenght?

And by the way is there any chance that we can observe the electroweak interaction unified with the strong interaction at the Large Hadron Collider??

Thanks

 

[blechman]

Hi:

The electromagnetic and weak interactions were unified in what is called the electroweak interaction, but as long as I know they are different classes of interactions, what I mean is that in weak interactions, there are particles that transform in others (like neutron's beta decay) and in electromagnetic interactions, particles repel or are atracted to each other...

If they are so different, how can they be unified ? or is it just that the interactions have almost the same strenght?

I don't understand this question. Historically, it WAS something of a surprise that the weak nuclear force could be unified with electromagnetism. But it could! The math works out, and the predictions were confirmed by later experiments. I wasn't alive in the 1960's when these models were being published, so I can't comment on what Weinberg was THINKING when he decided that this might work... But that's what separates the smart people from the geniuses!

To understand precisely how this happens, you need to have a firm understanding of Quantum Field Theory. I'm not sure what your background is, so I won't say any more about that here.

And by the way is there any chance that we can observe the electroweak interaction unified with the strong interaction at the Large Hadron Collider??

Thanks

Nope. Strong-EW unification is predicted to happen at an energy scale of around 10^{16} GeV, which is 10^{12} orders of magnitude above the energy scales of the LHC. So any predictions of GUT's would be dramatically suppressed (naively 1 part in 10^{24}), unless there was something totally unexpected. People are looking, but no one expects to find any direct evidence of GUT physics...

 

[ophase]

In Standard Model, Electromagnetism is not just particles repel or are attracted each other ..etc.
Electroweak Theory actually takes electromagnetism as a perturbation theory of the electromagnetic quantum vacuum (QED). So according to Quantum ElectroDynamics one has to deal with "electron and photon interactions" like compton scattering. I think It is important to understand QED theory to understand the electroweak theory soon.

I don't believe that LHC datas will show the GUT directly. For this kind of Unification theory, one should complete the mathematical background behind the GUT. It won't be a big surprise for me if the whole GUT theory constructed inside out.