Neutrino mass problem

Let us recall the problem of neutrino mass. Immediately after receiving... 

Despite all these impressive progress, we are still too far from the ultimate theory of everything. I listed some obvious avenues for future research in particle physics and cosmology. If I am allowed to say my personal prejudice, I would say that the flavor problem is beyond our reach for years to come, but our understanding of the law of force may further be advanced by a new discovery of violation of empirical conservation laws. The Majorana nature of neutrino masses and proton decay are just manifestation of violation of lepton and baryon numbers, and in my view there is no fundamental obstacle against these being discovered in future, however remote it might be. 

Note that reaction (3) will be induced by v, v, and v, although with different rates. Measurement of the rates of reactions (l)-(3) should go far toward a definitive solution of the neutrino oscillation problem and, ultimately, toward absolute numerical values of neutrino masses. 

In Chap. 1, we introduced the book with a quote from Albert Einstein (Schilpp 1949), which read in part that classical thermodynamics... is the only physical theory of universal content concerning which I am convinced that, within the framework of the applicability of its basic concepts, it will never be overthrown. An important qualification to this statement is the phrase within the framework of the applicability of its basic concepts. The laws of thermodynamics are based on laboratory-scale experiments. To assume that such laws are applicable to the Universe is a big assumption. However, we have no evidence yet that contradicts this assumption on the scales of problems relevant to life. Moreover, there remain vast cosmological questions with no answers and definitely no understanding of implications even if we knew the answers. For instance, does the proton have a very long but finite radioactive half-life Does the neutrino have a very small but finite mass Is the Universe opened or closed with respect to expansion and gravitational contraction Also, the Universe may not be isolated with respect to matter/energy or it could be isolated and cyclical. 

Neutrinos can be cold dark matter if their masses are around few GeV or a TeV. However, fourth-generation heavy neutrinos lighter than 45 GeV are excluded by the measurement of the Z-boson decay width at the Large Electron-Positron collider at CERN. Moreover, direct searches for WIMP dark matter in our galaxy exclude Dirac neutrinos heavier than 0.5 GeV as the dominant component of the galactic dark halo (see Figure 3). Thus although heavy Dirac neutrinos could still be a tiny part of the halo dark matter, they cannot solve the cold dark matter problem. 

Whatever the outcome, great repercussions on science resultfrom the solar neutrino problem. The implications may be for our Sun, or for the nature of neutrinos, or both. Recent evidence is convincing that the problem is in the nature of the neutrino itself namely, that during transit it spontaneously transforms (oscillates) to a neutrino of different flavor, and to which the detector is insensitive. This is possible because of the small rest mass of neutrinos. 

Decay-Induced Rearrangement of the Molecular Electron Shell and the Problem of Determining the Neutrino Rest Mass... 

The admission that mv 0 solves the problem of the concealed mass. The mass of a galaxy determined by its rotation as a whole considerably exceeds the sum of the observed stellar masses. This difference must be attributed to the unobserved black holes. However, according to the motion of galaxies, the main part of the concealed mass is distributed along their peripheries. The nonzero mass of the neutrino explains such a distribution of masses. 

The problem of the nonzero rest mass of neutrinos cannot be considered as solved at present. The results obtained by the ITEP group are under active... 

In Section I we made a brief excursion into the history of studies devoted to the estimation of the neutrino rest mass in this regard we pointed out the importance of the problem, first raised by Bergkvist (1971, 1972), of taking... 

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