Only e-, e+, photons. String theory more simple?

In summary, the possibility of a Universe with only electrons, positrons, and photons is dependent on the type of interaction between these particles. If the interaction is similar to regular electromagnetism, then it would not be possible due to QED diverging at extreme energies. However, in simpler toy theories, this could be a possibility. As for string theory, while it can explain multiple particles with a single parameter, it would not work without the presence of high energy scalars. A potential theory that could result in only electrons, positrons, and photons is a quantum theory of Kaluza-Klein's original work in 4+1 dimensions, but it would likely have issues as a quantum theory.
  • #1
Spinnor
Gold Member
2,216
430
I'm guessing string theory might get a lot simpler if there were only electrons, positrons, photons, and gravitons around?

Mathematically could there be a Universe with only electrons, positrons, and photons? If so, how many dimensions would such a string theory need?
 
Physics news on Phys.org
  • #2
Spinnor said:
Mathematically could there be a Universe with only electrons, positrons, and photons?

If the force between the electrons and positrons resembles regular electromagnetism, then the answer is no. This is because QED diverges at extreme energies, and so we know that it must only be the low-energy limit of another, which turns out to be electroweak.

It is possible, however, if we replace the electromagnetic interaction with a simpler interaction. These 'toy' theories are widely used in teaching.

As for string theory, one of its primary strengths is that it can explain a large number of particles in terms of a single parameter. Historically strings were first considered as a model of the strong force, until they predicted gravity (which is much more difficult).
 
  • #3
String theory would be a lot simpler, it wouldn't work at all. There are high energy scalars that must be present in the theory for consistency reasons. Likewise you cannot add or subtract interactions willy nilly like in qft.

Instead you are looking for something more like a quantum theory of Kaluza-Kleins original work in 4+1 dimensions, where its just EM and gravity that drop out. It would definitely be badly behaved as a quantum theory though.
 

1. What is the difference between e- and e+ in string theory?

In string theory, e- refers to an electron, which is a fundamental particle with a negative charge. On the other hand, e+ refers to a positron, which is the antiparticle of an electron and has a positive charge. In string theory, these two particles are described as vibrations of a string.

2. How do photons fit into string theory?

Photons, which are particles of light, are also described as vibrations of a string in string theory. These vibrations or oscillations of the string give rise to the electromagnetic force, which is responsible for interactions between charged particles.

3. Why is string theory considered simpler than other theories?

String theory is considered simpler because it attempts to unify all of the fundamental forces of nature (gravity, electromagnetism, strong and weak nuclear forces) into one theory. This is in contrast to the Standard Model which requires separate theories for each force.

4. What is the role of e-, e+, and photons in string theory?

In string theory, e- and e+ are considered to be the building blocks of matter, while photons are the carriers of the electromagnetic force. These particles are described as vibrations of a string, which is the fundamental object in string theory.

5. How is string theory related to the concept of a unified theory?

String theory is often referred to as a "theory of everything" because it attempts to unify all of the fundamental forces of nature and explain the properties of matter. This includes unifying gravity with the other three forces, which has been a major challenge for physicists. While string theory is not yet proven, it is a step towards achieving a unified theory.

Similar threads

Roughly how many people in this world actually know about string theory?
    • Beyond the Standard Models
Replies
10
Views
2K
A String Theory in N dimensions?
    • Beyond the Standard Models
Replies
1
Views
1K
B Balancing theories and empirical data, especially concerning string theory
    • Beyond the Standard Models
2
Replies
47
Views
4K
I What Shapes Can Extra Dimensions Take in String Theory?
    • Beyond the Standard Models
Replies
2
Views
2K
A The double copy of (2,0) theory
    • Beyond the Standard Models
Replies
1
Views
2K
A Different symmetries or no symmetries in string theory?
    • Beyond the Standard Models
Replies
4
Views
1K
A Branes with any number "n" of dimensions and laws of physics?
    • Beyond the Standard Models
Replies
1
Views
1K
A Sum over backgrounds in String Theory
    • Beyond the Standard Models
Replies
4
Views
2K
I What maps are considered in the Polyakov path integral?
    • Beyond the Standard Models
Replies
0
Views
1K
A What is the Best Resource for Learning String Theory as a Side Project?
    • Beyond the Standard Models
Replies
2
Views
1K

Hot Threads

Recent Insights

Back
Top