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4

Firstly: *in a vaccuum *inertial Einstein's Special Theory of relativity postulates that the speed of light in a vacuum is same for all inertial frames. suppose a neutrino is there moving at the speed of light For a neutrino to move at $c$, it has to be a massless particle. We're not sure of that yet. Apparently the existence of neutrino ...

10

Cute question! For a neutrino with mass $m$ and energy $E\gg m$, we have $v=1-\epsilon$, where $\epsilon\approx (1/2)(m/E)^2$ (in units with $c=1$). IceCube has detected neutrinos with energies on the order of 1 PeV, but that's exceptional. For neutrinos with mass 0.1 eV and an energy of 1 PeV, we have $\epsilon\sim10^{-32}$. The time of flight for ...

-3

Because the neutrinos follow a straighter line. The visible light that reaches your eye/telescope has been pulled back and forth by various influences such as gravitational pull along its long path to you. The neutrinos have taken a straighter route because they are much less influenced.

3

Here's the reported article on the neutrino detection which has the phrase. To answer your title, neutrinos have a very small mass. They don't carry charge which makes them invulnerable to EM radiation. But, they still interact with charged particles such as electrons, protons and muons. Fast neutrinos can interact with electrons in some medium (like water) ...

19

They are probaby talking about supernovae, like how SN1987A was first detected by neutrinos before the light arrived. In that case neutrinos and photons are both produced in the core of the supernovae explosion, but they have dense clouds of gas to get through before they get to empty space and travel freely to us. Since the neutrinos are weakly interacting ...

2

You can generate Dirac neutrino masses through the Higgs mechanism by introducing right handed neutrinos (in the same way you generate masses for the upper quarks). Since neutrino masses are at the sub-$eV$ scale, this means that the Yukawa couplings have to be unnaturally small, of order $10^{-12}$. People prefer to keep $\mathcal{O}(1)$ Yukawa's and ...

11

Possible extragalactical sources for high energy neutrinos is still an open question. There are several candidates, look at this paper on arXiv. By the way, astrophysical neutrinos have been already detected more than 20 year ago by Kamiokande in Japan. They came from supernova SN 1987A, and helped to set an upper bound (of about $10\ \text{eV}$) on the sum ...

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