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Understanding Electron and Neutrino Mass Relationships

Examining the connection between electron mass and neutrino mixing behaviors.

― 5 min read


Electron Mass andElectron Mass andNeutrino Mixing Insightsmass generation.A deep dive into electron and neutrino
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In the world of particle physics, we try to understand why certain particles have mass and how they interact. One area of interest is the behavior of electrons and their Neutrinos. Electrons are fundamental particles that carry a negative electric charge, while neutrinos are nearly massless particles that interact very weakly with other matter. The relationship between their masses and Mixing angles is complex and intriguing.

In standard models, we often see protection mechanisms for keeping certain particles massless. When applied to electrons, a specific symmetry can lead to their mass being zero. However, this same symmetry causes the mixing angles of their neutrinos to vanish. This poses a challenge because, in reality, we observe that neutrinos do mix, and they are believed to have mass.

Chiral Symmetry and Particle Mass

Chiral symmetry is a concept in physics that refers to how particles behave differently based on their handedness, or chirality. For instance, left-handed and right-handed particles interact with forces differently. In our context, if we impose a chiral symmetry on electrons, we find that it protects them, making their mass zero. However, this also leads to the result that their corresponding neutrinos cannot mix, which contradicts observations.

To resolve this contradiction, we must find a way to break the chiral symmetry without completely losing the benefits it provides. By doing so, we can allow for the existence of neutrino mixing while still maintaining a small electron mass. This creates a pathway to understand how the mass of the electron can be generated through a process involving the mixing of other particles.

The Role of Higgs Fields

Higgs fields play a crucial role in particle mass generation. In our model, we can introduce particles called Higgs triplets alongside the typical Higgs doublet. When these Higgs fields interact with the leptons (which include electrons and neutrinos), they can give mass to these particles through different mechanisms.

In one of the approaches, the Higgs triplet can be broken in such a way that maintains the small mass of the electron, while simultaneously allowing neutrinos to mix freely. This mixing is essential because it leads to the observed behavior of neutrinos in experiments.

Mixing and Mass Generation Process

When we explore how neutrinos mix, we often refer to a mechanism called the seesaw mechanism. This mechanism essentially explains why neutrinos are so much lighter than other particles, like electrons. Through this process, we use heavy particles to indirectly influence the mass of lighter particles.

In our scenario, when we break the symmetry in a specific way, the heavy Higgs fields influence their lighter counterparts. This influence results in the generation of mass for the electron and large mixing angles for the neutrinos.

Challenges in Model Building

Despite the promising framework, challenges remain. One significant issue is that in some models, a symmetry meant to protect the electron's mass can unintentionally suppress neutrino mixing. This creates a contradiction within the model that needs to be resolved.

To address this, we can introduce additional structures to the model, such as adding another type of Higgs field. This addition allows for the symmetry to be broken in a way that benefits both the electron and the neutrinos, covering the complexities of their interactions without compromising their mass relationships.

Renormalization Group Equations (RGE)

Renormalization Group Equations (RGE) are essential tools used in particle physics to study how physical quantities change with energy scales. By applying RGE to our model, we can track how the properties of particle masses evolve as we move between different energy levels.

In our case, as we analyze the underlying structures of the model, RGE calculations reveal how the different Yukawa couplings of particles interact with each other at varying scales. This study helps us predict the behavior of the electron mass and the neutrino mixing angles more accurately.

The Electron and Muon Mass

While we focus heavily on the electron, the muon, a heavier cousin of the electron, also plays a critical role in this discussion. We can develop a consistent framework in which both particles can acquire mass through similar mechanisms.

By taking into account the interactions of the muon and its specific properties, we can adjust the parameters in our model to ensure that both the muon and the electron achieve their respective masses.

Testing the Model

One of the most exciting aspects of any theoretical model is its potential to be tested through experiments. In our case, we can look forward to upcoming neutrino experiments, which may provide crucial insights into the validity of our model.

Experiments are designed to detect the nuances of neutrino behavior, including their mixing angles and any potential violations of symmetry, such as Charge Parity (CP) violation. By carefully analyzing the data from these experiments, we can either support or challenge our theoretical predictions.

Implications for CP Violation

CP violation is a critical concept in particle physics, as it helps explain the asymmetry between matter and antimatter in the universe. Our model suggests that the strong CP phase, which is generated through the interactions of leptons, can provide insights into whether CP violation occurs in the neutrino sector.

If our model is correct, we can expect specific relationships between the observed values of electron and muon masses and the presence or absence of CP violation in neutrinos. Further experiments will be vital in clarifying these relationships.

Conclusion

The relationship between the masses of electrons, muons, and their neutrinos is a complex but fascinating topic in particle physics. By breaking chiral symmetry in a controlled manner, we can generate mass for these particles while allowing their neutrinos to mix in accordance with experimental observations.

Our model provides a comprehensive approach that integrates various elements, like Higgs fields and RGE, to create a coherent framework for understanding particle mass and mixing. Future experiments will ultimately determine the viability of our predictions and help illuminate one of the fundamental mysteries of the universe: the origin of mass.

Original Source

Title: Parity and lepton masses in the left-right symmetric model

Abstract: Curiously in the minimal left right symmetric model, chiral symmetry that protects the electron's mass ($m_e$), due to parity (P), implies in the symmetry limit the vanishing of its neutrino mixing angles. We break the chiral symmetry softly (or spontaneously if it is gauged) to generate the observed large neutrino mixing angles at the tree-level. The electron then acquires its mass on renormalization group equation (RGE) running due to its neutrino's mixing, and in turn determines the $B-L$ gauge symmetry breaking scale ($v_R$) to be $10^{10} GeV \lesssim v_R \leq 10^{15} GeV.$ If the muon's mass is also generated radiatively, the $B-L$ breaking scale is $\sim 10^{14-15}$ GeV. Regardless of the high scale of $v_R$, this is a testable model since on RGE running and P breaking, a large strong CP phase ($\bar{\theta} >> 10^{-10}$) which depends logarithmically on $v_R$ is generated if there is $\mathcal{O}(1)$ CP violation in leptonic Yukawa couplings. Hence we expect that leptonic CP phases including the Dirac CP phase $\delta_{CP}$ of the PMNS matrix must be consistent with $0$ or $180^o$ to within a degree, which can be verified or excluded by neutrino experiments such as DUNE and Hyper-Kamiokande. In lieu of P, if charge conjugation C is used, the same results follow. However with C and no P, axions would likely need to be added anyway, in which case there is no constraint on $\delta_{CP}$.

Authors: Ravi Kuchimanchi

Last Update: 2024-12-13 00:00:00

Language: English

Source URL: https://arxiv.org/abs/2406.14480

Source PDF: https://arxiv.org/pdf/2406.14480

Licence: https://creativecommons.org/licenses/by/4.0/

Changes: This summary was created with assistance from AI and may have inaccuracies. For accurate information, please refer to the original source documents linked here.

Thank you to arxiv for use of its open access interoperability.

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