Transcript ECRS2016-Alavi

Neutrino oscillations and
Lorentz invariance violation
`Standard Model’ Neutrinos
Two families of elementary particles …
Neutrinos:
• Come in three `flavors’ (e,)
• Are massless
• Interact weakly
• Cannot change flavor
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Brief history of neutrinos
Pauli postulated neutrinos to explain how beta decay could
conserve energy, momentum, and spin 1930.
Detection of the neutrino (1995 Nobel prize）
μ-neutrino discovery（1988 Nobel prize ）
Pontecorvo proposed neutrino oscillation 1957
Detection of cosmic neutrinos (2002 Nobel prize ）
Discovery of neutrino oscillations（2015 Nobel prize ）
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Neutrino oscillation :
⧫. is a quantum mechanical phenomenon
⧫ ⧫. A neutrino created with a specific lepton flavor
(electron, muon, or tau) can later be changed to a
different flavor.
⧫ ⧫ ⧫ . The probability of measuring a particular flavor for a
neutrino varies periodically as it propagates through space.
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Neutrino Oscillation in Vaccum
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Neutrino oscillations in normal media
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Neutrino Oscillation in nuclrar media
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Lorentz invariance is one of the main and basic concepts in special
relativity (for more than one century).
It states that :
The laws of physics are invariant under Lorentz transformation.
Lorentz invariance imply that spacetime structure is the same at all
scales; that is, Lorentz symmetry assumes a scale-free nature of
spacetime. there is no fundamental length scale associated with the
Lorentz group.
A departure from Lorentz invariance can therefore lead to discontinuous
spacetime framework and vice versa.
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But the existence of fundamental length and discreteness of space
are predicted by some theories including, quantum gravity, string
theory and noncommutative geometry.
So there is possibility of Lorentz invariance violation (LIV) in nature.
A question :
Can we check Lorentz invariance violation by neutrino
oscillations?
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To formulate the neutrino oscillation in a discrete space
(lattice) we follow the method proposed in :
K. G. Wilson, Phys.Rev. D 10 (1974) 2445.
J. B. Kogut, Rev. Mod. Phys. 55 (1983) 775.
I. Motie, She-Sheng Xue, IJMPA 19 (2012) 1250104.
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In conclusion, high energy
neutrinos oscillations may
help us to get information
about LIV.
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Thank you and the organizing committee
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