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Physicists detect signs of neutrinos at Large Hadron Collider

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Re: Physicists detect signs of neutrinos at Large Hadron Collider

#61

Post by hinkley »

lnauta wrote: post #14
xwdv wrote: post #7

What happens if a neutrino interacts with something?

That depends on the energy of the neutrino, for lower energies there will be some momentum exchange, but since neutrinos are extremely light, this may be neglected depending on your experimental setup. At higher energies (>GeV) depending on the interaction type (whether a W-boson or a Z-boson is exchanged), a charged lepton comes out, which can be an electron, muon or tau (the tau decays very fast) and this is the sa…

Do we calculate the weight of all neutrinos in the Known mass of the universe? Or is that part of Dark Matter?

What is the mass of all the neutrinos in a cubic meter of “vacuum”?

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#62

Post by dr_dshiv »

Koshkin wrote: post #55
LegitShady wrote: post #48

Earlier quoted context omitted.

It's not yet clear if gravitons exist at all.

I have a hard time imagining a particle associated with the curvature of spacetime.

I had a really hard time imagining a particle associated with mass (Higgs boson)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#63

Post by retrac »

wyldfire wrote: post #59
tehsauce wrote: post #47

Earlier quoted context omitted.

I think this would be impossible without truly alien materials.

Really? Seems like if we were motivated to do it, we could have a network of Earth satellite detectors in ~a century or so.

"If the sensitivity gets high enough" is the big if to my conjecture. We may never be able to detect enough neutrinos to be reliably detect multiple coming from the same source passing through multiple detectors.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#65

Post by [deleted] »

traeregan wrote: post #42
dmitrybrant wrote: post #28

Earlier quoted context omitted.

While neutrinos are not very difficult to generate, they are extremely, astoundingly difficult to detect. Unless we discover a new type of matter that interacts more strongly with neutrinos, we're stuck with cavern-sized detectors that can detect single-digit numbers of neutrinos (out of many trillions), unreliably.

> Unless we discover a new type of matter that interacts more strongly with neutrinos How about astrophage? :)

[deleted]

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#66

Post by jahnu »

idontwantthis wrote: post #25

Would there be any good reason or theoretically practical way to use neutrinos for communication? Asking because in 3 Body Problem it’s seen as a “civilized” way to communicate compared to radio waves.

We can collect enough over hundred of days to make a picture of the sun*. Bear in mind the absolutely unimaginable quantities of neutrinos the sun is producing every femtosecond just in our direction and we can barely detect them with a giant apparatus.

https://apod.nasa.gov/apod/ap980605.html

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#67

Post by whatshisface »

Ma8ee wrote: post #5
aardvark179 wrote: post #4

Earlier quoted context omitted.

It’s interesting that you class dark energy (the thing accelerating universal expansion) as, “We don’t know,” but don’t put gravity into that same category. They are both aspects of general relativity that we have failed to integrate with our other most successful fundamental theories, but if you asked an average person on the street I’m sure they’d put them in very different categories of understanding, as you did.

The thing with gravity is that it is kind of easy to detect, even for a layperson, while dark energy and dark matter haven't been detected at all, by anyone, but only used as mathematical devices to make indirect measurements of large scale structures align with our models. So, it isn't only the "average man on the street" that thinks there are good reasons to put them in very different categories of understanding.

Curiously... In the way dark matter has never been detected (no particle has been found), gravity has never been detected, and in the way gravity has been detected (through its influence on the trajectories of detectable matter), dark matter has been as well.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#68

Post by LegitShady »

dr_dshiv wrote: post #62
Koshkin wrote: post #55

Earlier quoted context omitted.

I have a hard time imagining a particle associated with the curvature of spacetime.

I had a really hard time imagining a particle associated with mass (Higgs boson)

note that the Higgs is not responsible for all mass as is understood by a layperson. The Higgs field gives mass to subatomic particles but it doesn't translate directly into the mass of objects as we know them.

The mass of the three quarks (one up quark and two down quarks) making up a neutron is only about 1% of the mass of a neutron. The rest of the mass comes from strong nuclear force interactions via gluons which are themselves massless.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#69

Post by rowanG077 »

postalrat wrote: post #49
YakBizzarro wrote: post #36

Earlier quoted context omitted.

your "opponent" is the sun that is bombarding us with tons of neutrinos. your SNR would be probably bad

Not so bad if your detector can detect the direction the neutrino came from.

As long as you have multiple detectors and a neutrino stream crosses them you can obtain the direction. I assume this is what the poster meant.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#70

Post by dclowd9901 »

WitCanStain wrote: post #29
hn_throwaway_99 wrote: post #27

Earlier quoted context omitted.

Neutrinos are produced by radioactive decay, and they interact very weakly with ordinary matter, making them extremely difficult to detect. Seems like the exact opposite qualities of something you'd want to use for communication.

If there were a way to reliably detect neutrinos in sufficient quantities they'd be ideal since you could send messages through the earth and at near light speed, I suppose.

This is important because… line of sight has somehow stymied us?

I feel like quantum entangled communication would be a better direction to head. Not that they’re mutually exclusive development paths.

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