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Physicists detect signs of neutrinos at Large Hadron Collider

phys.org

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Re: Physicists detect signs of neutrinos at Large Hadron Collider

#31

Post by JProthero »

pvg wrote: post #21
kordlessagain wrote: post #2

It’s always bugged me that science claims there are trillions of neutrinos going through me, yet can hardly detect them with a nearly trillion dollar machine and a doctorate. Then there’s dark energy, which just seems like a lame excuse for saying “we don’t know”. Nobody says what goes through my body but me! (I’m being funny, y’all! Happy holidays!)

John Updike wrote a poem about the crassness of neutrinos: http://www.physics.mcgill.ca/~crawford/PSG/PSG21/204_97_L21....

Excellent. I give this 10^14 / 10^14.

The pedant in me wants to point out that they are now known to have some mass and do interact a bit, but this was written in 1960.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#33

Post by JProthero »

adrian_b wrote: post #18
xwdv wrote: post #16

Earlier quoted context omitted.

So if we could force neutrino interactions at scale we could make any element we want in large quantities?

Using neutrinos is far less efficient than using gamma radiation or neutrons or high energy electrons or ions for transmutations. The photons/neutrons/electrons/ions have a high probability of interaction with the target, while the neutrinos have a very low probability of interaction. All the elements that do not exist in nature due to low lifetime have been produced by transmutation, but this can be done only for ve…

Thanks for a great couple of replies. I'd just add that there are almost certainly more superheavy elements not thought to exist in nature which have yet to be produced artificially, but probably will be at some point.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#34

Post by blablabla123 »

xwdv wrote: post #16
adrian_b wrote: post #15

Earlier quoted context omitted.

Usually the neutrino will interact with a nucleus and what happens is the reverse of a beta decay, i.e. either a proton will be changed into a neutron or a neutron into a proton, with the emission of an electron or a positron. So one atom will be converted into an atom of another element, which is a neighbor to it in the periodic table. Because one neutral lepton goes in and one charged lepton goes out, you might say…

So if we could force neutrino interactions at scale we could make any element we want in large quantities?

In some sense this is how particle collisions works. You collide something and with certain probability you get something else at the other end under the physical constraints. Probably you want to use bigger particles and lower energy though to go from subatomic to atomic/molecular scale. The laser ignition fusion experiments would be closer to that. (Mind the costs though :))

https://en.wikipedia.org/wiki/Stellar_nucleosynthesis

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#35

Post by mrfusion »

dmitrybrant wrote: post #28
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.

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.

I guess if we found a way to provide say a trillion times more neutrinos than normal we could detect that more easily.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#36

Post by YakBizzarro »

mrfusion wrote: post #35
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.

I guess if we found a way to provide say a trillion times more neutrinos than normal we could detect that more easily.

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

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#37

Post by R0b0t1 »

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.

Just generate inordinate amounts of neutrinos. Doable for something akin to a undersea cable. If we could focus the output of the reaction then I see this being feasible, otherwise maybe not.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#38

Post by DrBazza »

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.

The 'good reason' to use them for communication, if it were practical, is that they interact so weakly, you don't have to worry about pesky things like planets or stars getting in the way of your signal (though gravity is still a thing).

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#39

Post by JProthero »

jiggawatts wrote: post #26
lookatme wrote: post #19

Earlier quoted context omitted.

In all seriousness, I found myself wondering about those numbers before; but consider that there's on the order of 10^27 atoms in your body. So, if we assume a trillion neutrinos in your body, that indicates that for each neutrino in your body, there are 10^15 atoms - that's one part per quadrillion! A machine capable of detecting neutrinos in your body would need to be _unimaginably_ sensitive, before even consideri…

Look at it this way: Solar neutrinos carry away approximately 1% of the total fusion power output of the Sun. This works out to about 14 Watts per square meter at the distance of the Earth. The area of a human adult body front-on is about a square meter. It's pretty easy to detect 14 W of typical forms of radiation at those scales! If it were light, it would be equivalent to the light put out by something like a lapt…

This is a great analogy, I'd never seen it translated into tangible terms like that before.

I remember reading that, at close enough range, the neutrino emissions from a supernova would be intense enough to be dangerous to structures made of ordinary matter, despite the weakness of their interactions, and that they would reach an observer earlier than other forms of radiation due to their ability to escape the collapsing star relatively unimpeded. Neutrinos would be the least of your problems if you were the observer of course.

As I was trying to find a source for this, I discovered there is a unit [1] for the amount of energy released by a supernova called the Foe, which seems apt (it's an acronym derived from 'ten to the power of Fifty-One-Ergs').

[1] https://en.wikipedia.org/wiki/Foe_(unit)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#40

Post by chasil »

dmitrybrant wrote: post #28
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.

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.

From the article:

"Casper said that there have only been about 10 observations of tau neutrinos in all of human history but that he expects his team will be able to double or triple that number over the next three years."

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