Speed of neutrinos - latest results?

  • Context: High School 
  • Thread starter Thread starter DaveC426913
  • Start date Start date
  • Tags Tags
    Neutrinos Speed
Click For Summary

Discussion Overview

The discussion revolves around the speed of neutrinos, particularly in light of past controversies regarding measurements that suggested they might exceed the speed of light. Participants inquire about recent studies or confirmations of neutrino speeds since the OPERA experiment and express uncertainty about the current understanding of neutrino mass and speed.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants note that the OPERA experiment's findings were later debunked, but they question whether the issue is conclusively settled.
  • There is a suggestion that neutrinos are predicted to travel very close to the speed of light, but recent measurements are lacking.
  • One participant argues that there is no singular "speed of neutrinos," as it depends on their mass, which is still a matter of debate.
  • Another participant emphasizes that if neutrinos have mass, their speed cannot be defined as a single value.
  • Some express frustration over the lack of recent articles confirming the speed of neutrinos, despite the belief that they have mass.
  • There are discussions about the challenges of measuring low-energy neutrinos and the implications for special relativity.
  • Participants mention that astrophysical observations and supernova emissions provide some bounds on neutrino speeds and masses.
  • There is speculation about the possibility of neutrinos having a tachyonic nature, though this is not widely accepted.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the current understanding of neutrino speeds or the implications of their mass. Multiple competing views remain regarding the interpretation of past measurements and the current state of research.

Contextual Notes

There are unresolved questions regarding the mass of neutrinos and how it affects their speed. Participants highlight the limitations of existing measurements and the challenges in obtaining new data.

  • #31
We have never seen a neutrino from a supernova. We have only seen antineutrinos.

Neutrinos have a short emission time - a time scale of tens of milliseconds. Antineutrinos have a time scale of tens of seconds.

So a nearby galactic supernova would be 1000x better than 1987a? Not exactly - while we know the start time ~1000x better, it would also be ~1000x closer,. so the time difference is ~1000x smaller. And we're right back where we were. Maybe we'll do two or four times better, but not a thousand.
 
  • Like
Likes   Reactions: vanhees71
Physics news on Phys.org
  • #32
Hornbein said:
Is the idea that the higher energy neutrinos will be faster. Then if we can detect the pulses and the model for timing of the pulse origin is correct we can then calculate the rest mass. I suppose the problem is that at highly relativistic speeds the difference in velocity is tiny. Well, it's not my problem. Let someone else earn their PhD doing this.
The idea is that neutrinos get spewed out in advance of the the explosion itself fully manifesting in a particular pattern, and you need to model the process properly to make meaningful comparisons of different signals arriving from a distant source. You also need to model properly different routes that the neutrino could have taken to get from the source to Earth where it is detected.
 
  • #33
Vanadium 50 said:
We have never seen a neutrino from a supernova. We have only seen antineutrinos.

True but pretty pedantic. Obviously, in this context, one is talking about both neutrino and antineutrino observations when one is talking about what neutrino telescopes on Earth are seeing.

Vanadium 50 said:
Neutrinos have a short emission time - a time scale of tens of milliseconds. Antineutrinos have a time scale of tens of seconds.

So a nearby galactic supernova would be 1000x better than 1987a? Not exactly - while we know the start time ~1000x better, it would also be ~1000x closer,. so the time difference is ~1000x smaller. And we're right back where we were. Maybe we'll do two or four times better, but not a thousand.
This tradeoff is indeed a big deal and creates a sweet spot that is not too near and not too far.
 

Similar threads

High School Where Can I Find The New Daya Bay Results?
  • · Replies 7 ·
Replies
7
Views
2K
Undergrad How do the collider experiments measure the mass of the W boson?
  • · Replies 4 ·
Replies
4
Views
4K
High School Could Neutrinos Challenge Our Understanding of Physics?
  • · Replies 1 ·
Replies
1
Views
2K
Graduate Was the faster-than-light neutrino result a mistake caused by a loose cable?
  • · Replies 16 ·
Replies
16
Views
3K
Graduate The neutrinos of anomalous speed
  • · Replies 8 ·
Replies
8
Views
2K
High School Is the case for a Universal Speed Limit experimental or theoretical?
  • · Replies 41 ·
2
Replies
41
Views
5K
Undergrad Some questions about Cosmic Microwave Background radiation
  • · Replies 13 ·
Replies
13
Views
6K
High School Can an Object Exceed the Speed of Light?
  • · Replies 12 ·
Replies
12
Views
2K
Undergrad What false hints of new physics were most notable?
  • · Replies 30 ·
2
Replies
30
Views
9K
High School Why does it require an infinite amount of energy to reach the speed of light?
  • · Replies 130 ·
5
Replies
130
Views
15K