How Is the Lower Bound of Neutrino Mass Calculated?

[frazzle]

I was wondering if anyone could help clarify this problem I am having.

Upon reading a section in a paper, I am a bit stuck as to how this value of the lower bound of the neutrino mass is reached here. I have highlighted the relevant part in the snapshot below:http://img487.imageshack.us/img487/3...inomass3fk.jpg Is there something missing from this passage, or am I just missing something blindingly obvious? I can't seem to understand how the two squared mass differences coupled with the assumption of hierarchy lead to the quoted value!

in case you're curious, the paper is:

http://arxiv.org/abs/astro-ph?papernum=0407207

thank you for reading!

 

[frazzle]

no worries, I've figured it out now.

 

[sir-pinski]

The lower bound of the neutrino mass is a topic that has been extensively studied and debated in the scientific community. It is a value that is still not fully understood and is subject to ongoing research and discoveries.

From the passage you highlighted, it seems that the authors are discussing the lower bound of the neutrino mass in the context of the cosmological model they are working with. They mention that the value of the lower bound is related to the squared mass differences and the assumption of hierarchy.

To understand this, we need to first understand the concept of neutrino mass hierarchy. Neutrinos come in three different types or flavors - electron, muon, and tau. The squared mass differences mentioned in the passage refer to the differences in the squared masses of these different flavors of neutrinos. The assumption of hierarchy refers to the order in which these squared mass differences are arranged - either in an increasing or decreasing order.

Based on current experimental data, scientists have observed that the squared mass differences are not equal for all three flavors of neutrinos. This implies that there is a hierarchy in the masses of these neutrinos. Now, based on this hierarchy and the assumption of a minimum value for the squared mass differences, scientists can calculate the lower bound for the neutrino mass.

However, it is important to note that this lower bound is still a theoretical calculation and there is no direct experimental evidence to support it. It is also subject to change as we continue to study and understand neutrino properties.

I hope this explanation helps clarify the concept of the lower bound of the neutrino mass. It is a complex topic and it is completely understandable to have doubts and questions about it. Keep exploring and learning, and don't be afraid to reach out for clarification when needed.