Neutrinos are light, uncharged leptons. The neutrino tag should be applied to question relating to neutrino properties or interactions involving neutrinos.
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713 views
How do we know Dark Matter isn't simply Neutrinos?
What evidence is there that dark matter isn't one of the known types of neutrinos?
If it were, how would this be measurable?
0
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1answer
95 views
Neutrinos and Speed of light
Einstein's Special Theory of relativity postulates that the speed of light is same for all frames.
Suppose a neutrino is there moving at the speed of light. Then will that neutrino also be flowing ...
25
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1answer
463 views
Neutrinos vs. Photons: Who wins the race across the galaxy?
Inspired by the wording of this answer, a thought occurred to me. If a photon and a neutrino were to race along a significant stretch of our actual galaxy, which would win the race?
Now, neutrinos ...
5
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3answers
564 views
How can neutrinos “beat light”?
Article in the CERN newsletter "symmetry breaking" has the following statement:
"Neutrinos are often the first particles to bring news of events in space to Earth, beating even light.". What does this ...
5
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1answer
100 views
Mechanisms of mass generation for Dirac neutrinos
If neutrinos are Majorana particles, one way of explaining their small masses is the seesaw mechanism.
Now say I'd like my neutrinos to be Dirac, for symmetry to the quark sector. What mechanisms ...
16
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1answer
277 views
Where do high-energy neutrinos come from?
Last week the IceCube South Pole Neutrino Observatory published a press release reporting the possible discovery of two neutrinos with energies of over 1 PeV.
Would anyone here be willing to help me ...
2
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0answers
28 views
Do small-angle coherent scattering experiments really see coherent effects over arbitrarily large distances?
Short version
After integrating over all possible outgoing angles, the total cross-section of coherent elastic scattering from a fixed target of characteristic length $L$ scales like $L^4$. Does ...
2
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0answers
60 views
About the seesaw mechanism
I was reading about the seesaw mechanism in my Lecture notes and got a technical question. See for example
http://www.lhep.unibe.ch/img/lectureslides/9_2007-11-30_SeeSawMechanism.pdf
page 13.
There ...
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0answers
24 views
Effective amplitude in Neutrinoless double beta decay
Can someone give me the value of the effective amplitude($A$) of $\bar{\nu_\mu}\rightarrow\nu_\mu$ oscillation of Neutrinoless double beta decay? The expression is like this:
...
5
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2answers
116 views
Do neutrinos of any flavor get trapped in black holes?
This question has been bothering me a bit. I know that neutrinos have super small mass and they interact via the weak force. Since they have a non-zero mass, they should be affected by black holes and ...
2
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0answers
37 views
How to get from angular velocity to acquired phase for neutrino oscillations in matter?
I am reading Akhmedovs 2000 paper on parametric resonance, and I cannot figure out the math of this particular passage:
The difference of the neutrino eigenenergies in a matter of density $N_i$ is ...
1
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2answers
98 views
Can the speed of an electromagnetic wave be measured in the absence of neutrinos?
Let me explain better: from what I understand neutrinos are so pervasive they are literally everywhere. And since they have such a tiny electric charge they barely interact with anything and cannot be ...
8
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4answers
409 views
strange modulation of radiactive decay rates with solar activity
Recently i found out this uber strange article about nuclear decay rates being somehow showing seasonal variations with a high correlation with sun activity. Two very precise questions:
1) has this ...
2
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2answers
102 views
How much energy is carried away by neutrinos in matter-antimatter annihilation?
Some people say that neutrinos carry away most of the energy, some others say just a fraction. So what is the truth ? what is the percentage of energy lost due to neutrinos ?
8
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1answer
254 views
Are right handed neutrinos actually antineutrinos and vice versa?
Is it experimentally ruled out that right-handed neutrinos are actually antineutrinos, and left-handed antineutrinos are neutrinos ?
31
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5answers
145 views
Models of neutrinos consistent with OPERA's results
I guess by now most people have heard about the new paper (arXiv:1109.4897) by the OPERA collaboration which claims to have observed superluminal neutrinos with 6$\sigma$ significance. Obviously this ...
12
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3answers
91 views
If neutrinos travel faster than light, how much lead time would we have over detecting supernovas?
In light of the recent story that neutrinos travel faster than photons, I realize the news about this is sensationalistic and many tests still remain, but let's ASSUME neutrinos are eventually proven ...
2
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0answers
79 views
Question on “new CNGS/OPERA measurement of neutrino velocity” (hep-ex/1212.1276)
A "new measurement of the limit on muon neutrino velocity with respect to the speed of light " by the OPERA neutrino experiment in collaboration with CERN has become public recently, as preprint ...
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2answers
241 views
How neutrinos can be harmful?
What are the circumstances in which neutrinos can harm humans or even kill them.?
2
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2answers
107 views
What is difference between the different 'flavours' of neutrinos?
Moreover, how-come scientist know that muon-neutrino are different from electron-neutrino when they didn't even know what the difference was? Did they interact differently with other particles?
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0answers
122 views
Neutrino mass with Dirac and Majorana
Why both Dirac mass and Majorana mass terms are needed to explain the mass of a neutrino?
4
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4answers
412 views
Neutrino versus Anti-neutrino Detection
Is there a that detection method in use that can distinguish between a neutrino from its anti-neutrino?
0
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1answer
133 views
“Conceptualizing” neutrinos
Layman here. EE and BS physics. I am "content" in viewing photons/electromagnetic radiation as an "emergent" property of spacetime? due to the electrons ("particles..?") and all their activity jumping ...
2
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1answer
225 views
How 'Faster Than Light' Neutrino Was Product of Loose Cable at CERN?
A "faster than light" neutrino discovery was actually the result of a loose cable.
A fiber-optic cable in a GPS receiver at the European Center for Particle Physics ( CERN) near Geneva
Can someone ...
9
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3answers
635 views
Why do or don't neutrinos have antiparticles?
This was inspired by this question. According to Wikipedia, a Majorana neutrino must be its own antiparticle, while a Dirac neutrino cannot be its own antiparticle. Why is this true?
4
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1answer
55 views
Is it proven that all “solar” neutrinos are coming from the Sun direction?
In "Observation of 8B solar neutrinos in the Kamiokande-II detector" (Phys.Rev.Lett., 63, 16(1989), http://prl.aps.org/pdf/PRL/v63/i1/p16_1) the Figure 2 shows that only small percentage of registered ...
15
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6answers
4k views
What would be the effects on theoretical physics if neutrinos go faster than light?
Earlier today, I saw this link on Facebook about neutrinos going faster than the speed of light, and of course, re-posted. Since then, a couple of my friends have gotten into a discussion about what ...
0
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1answer
184 views
Does a coronal mass ejection change solar neutrino emission rates?
Does the CME and neutrinos have any relation? CME is measured by Corona graphs.. How do they measure neutrinos coming from the sun? Does any of these have effects on earth's magnetic field or ...
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1answer
103 views
Why is neutrino beam not considered light?
I am trying to understand why physicists consider a neutrino beam not to be light.
Here's the research that I did to find the answer:
...
10
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1answer
130 views
The transit of Venus and solar neutrino rates
The following question was posed at the end of Maury Goodman's June 2012 long-baseline neutrino newsletter.
During the Venus transit of the sun, were more solar neutrinos
absorbed in Venus, or ...
9
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2answers
87 views
Can neutrino detectors tell what direction the neutrinos came from?
I was reading this question and got to thinking. Can neutrino detectors give us any clue where the neutrinos came from or when a supernova may occur? I was unsure and decided to ask that here.
1
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3answers
167 views
Neutron decay and electron anti neutrino $n\to p + e + \bar{\nu}_e$
Why do we need neutrino to explain neutron decay?
Is there any evidence regarding existence neutrinos in the context of
$n\to p + e + \bar{\nu}_e$?
0
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0answers
29 views
Can neutrinos be the dark matter [duplicate]
Possible Duplicate:
How do we know Dark Matter isn't simply Neutrinos?
If there are primardian neutrinos and since they have some mass however low, could neutrinos form the dark matter ...
0
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0answers
24 views
Neutrinos and the Cosmic Speed Limit [duplicate]
Possible Duplicate:
Superluminal neutrinos
An article in the newspaper a few months ago said that Neutrinos travel faster than Light. Another article then said that this observation was ...
2
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3answers
148 views
When a high speed neutrino just misses an old neutron star, why isn't it trapped?
Suppose a neutrino is seen travelling so fast that its Lorentz gamma factor is 100,000. It races past an old, no longer active neutron star, narrowly missing it. As far as the neutrino is concerned, ...
9
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1answer
233 views
Neutrino Oscillations and Conservation of Momentum
I would like to better understand how neutrino oscillations are consistent with conservation of momentum because I'm encountering some conceptual difficulties when thinking about it. I do have a ...
8
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2answers
624 views
How can neutrinos oscillate though the lepton flavors have differing masses?
Since the total mass-energy for the neutrino presumably does not change when a neutrino changes lepton flavor, though the mass is different, what compensates for the gain or loss of mass? Does the ...
2
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0answers
162 views
Neutrino path bent by gravity? [duplicate]
Possible Duplicate:
Neutrino unaffected by gravity
Other probably closely related questions here:
Link Neutrinos unaffected by gravity
Link Superluminal Neutrinos
My question is subtly ...
3
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1answer
84 views
Neutrino Oscillation and their gravitational implications
As I understand neutrinos, there are three different flavors, all with different masses. Although the masses of these neutrinos have not been directly measured, their mass differences have been. ...
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2answers
171 views
When Physicists thought neutrinos were faster than the speed of light [duplicate]
Possible Duplicate:
Superluminal neutrinos
I remember not too long ago hearing very much speculation about a discovery that perhaps neutrinos are faster than the speed of light.
I've heard ...
2
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2answers
601 views
Are neutrinos affected by gravity?
Layman here, but EE and BS physics. I know that light is affected by gravity. But are neutrinos? During the collapse of a star into a neutron star, as the electrons join protons to form neutrons ...
1
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1answer
370 views
How to calculate the density of relic neutrinos?
May be not neutrinos, but antineutrinos? Or both types?
In the last case, why they didn't annihilate and what is the ratio of relic neutrinos to relic antineutrinos? Is that ratio somehow related to ...
1
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1answer
88 views
Neutrino beam energy
Neutrino is one of the most mysterious particles in todays physics. Even when values of some parameters like for example mass associated with it are not known (or there is great range of possible ...
4
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1answer
706 views
What do “tachionic” neutrinos mean for QG?
Reading about the spectacular Opera claim, I`m (again ;-P) wondering if a confirmation of superliminous neutrinos could help settle some still open quantum gravity issues ...?
In this post, Lumo ...
0
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3answers
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Units describing the behavior of neutrinos
http://proj-cngs.web.cern.ch/proj-cngs/Download/CNGSDGVE/cngsdgve.pdf
on page 13 I read that "the present plan is to provide nu_mu neutrinos with an energy between 5 and 30 GeV."
Wikipedia neutrino ...
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0answers
92 views
OPERA' s chief resigns [closed]
It was said that the chief of the experiment (that proposedly demonstrated faster than light behavior) resigned after a vote. What good justification could there be for voting him out of his position? ...
59
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13answers
6k views
Superluminal neutrinos
I was quite surprised to read this all over the news today:
Elusive, nearly massive subatomic particles called neutrinos appear to travel just faster than light, a team of physicists in Europe ...
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2answers
206 views
Neutrino and electromagnetic forces
I learned from Wikipedia that neutrinos "are not affected by the electromagnetic forces". How was this identified experimentally?
6
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2answers
321 views
Neutrino oscillations versus CMK quark mixing
I wish to describe in simple but correct terms the analogy between the Cabibbo–Kobayashi–Maskawa (CMK) and Pontecorvo–Maki–Nakagawa–Sakata (PMNS) matrices.
The CMK matrix describes the rotation ...
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2answers
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“Dear radioactive ladies and gentlemen” - Letter by Wolfgang Pauli
In 1930, Wolfgang Pauli wrote a letter to Lise Meitner for a convention in Tübingen, considering the problem of beta decay.
Does anybody know, where to find the original letter online ?
