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Record-breaking neutrino is most energetic ever detected

nature.com

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Re: Record-breaking neutrino is most energetic ever detected

#31

Post by ars »

the_arun wrote: post #30
AnimalMuppet wrote: post #26

Earlier quoted context omitted.

This particle spread this energy through a volume of seawater a few km deep in the Mediterranean. It's going to raise the temperature of that volume a few billionths of a degree, if that. So, no, we can't.

What if our existing solar panels are optimized to detect these? Then will it improve the quality of solar panels to capture more energy from sunlight as well? Sorry, I'm no expert in this - asking more of a curiosity.

It's an enormous amount of energy packed into a single tiny particle.

But it's still just a single tiny particle, so it's not a lot of total energy.

It's like how you can lift a heavy weight for a second, but that's all you can do. You would need to be able to lift it for hours to be useful as a replacement for a crane. Same idea: Intensity vs total work.

Re: Record-breaking neutrino is most energetic ever detected

#32

Post by dahousecat »

GuB-42 wrote: post #25
antognini wrote: post #7

For context, 120 PeV is about 10% the kinetic energy of a ping pong ball during typical play.

Now, what will happen if you get hit by a ping-pong ball mass of 120 PeV neutrinos? 120 PeV is about 2e-16 grams, so a ping-pong ball will have about 1e16 of them. From nothing, to detectable, to lethal, to big boom? My intuition would be "detectable" but I don't know enough to do the maths. And by the way, I am using the mass-energy, not proper mass, because the question is crazy enough not to even consider what wou…

Sounds like a great topic for an xkcd video

Re: Record-breaking neutrino is most energetic ever detected

#34

Post by antognini »

GuB-42 wrote: post #25
antognini wrote: post #7

For context, 120 PeV is about 10% the kinetic energy of a ping pong ball during typical play.

Now, what will happen if you get hit by a ping-pong ball mass of 120 PeV neutrinos? 120 PeV is about 2e-16 grams, so a ping-pong ball will have about 1e16 of them. From nothing, to detectable, to lethal, to big boom? My intuition would be "detectable" but I don't know enough to do the maths. And by the way, I am using the mass-energy, not proper mass, because the question is crazy enough not to even consider what wou…

The mean free path of neutrinos through lead is around one light-year. So, taking the thickness of the body to be 1/2 a meter, you would expect the probability of any individual neutrino to interact with the body to be ~5 x 10^-17. So you'd ballpark have around a 20--40% chance that a single neutrino interacts with your body. It would probably cause a localized radiation burn. Detectable, but probably not lethal unless you got really unlucky with where it hit you.

Re: Record-breaking neutrino is most energetic ever detected

#35

Post by bauruine »

dahousecat wrote: post #32
GuB-42 wrote: post #25

Earlier quoted context omitted.

Now, what will happen if you get hit by a ping-pong ball mass of 120 PeV neutrinos? 120 PeV is about 2e-16 grams, so a ping-pong ball will have about 1e16 of them. From nothing, to detectable, to lethal, to big boom? My intuition would be "detectable" but I don't know enough to do the maths. And by the way, I am using the mass-energy, not proper mass, because the question is crazy enough not to even consider what wou…

Sounds like a great topic for an xkcd video

There is a what if about it. https://what-if.xkcd.com/73/

Re: Record-breaking neutrino is most energetic ever detected

#36

Post by queuebert »

ge96 wrote: post #33

What's faster than satellite communication? Neutrinos baby Not even sure if that's worth doing, either create/emit or use encode data into them as they fly by to be received by someone else Edit: that's cool people have tried though

Neutrinos can go straight through the Earth, yes, but since they have mass their velocity is less than c.

Re: Record-breaking neutrino is most energetic ever detected

#37

Post by shagie »

ge96 wrote: post #33

What's faster than satellite communication? Neutrinos baby Not even sure if that's worth doing, either create/emit or use encode data into them as they fly by to be received by someone else Edit: that's cool people have tried though

That's covered in RFC 1217. https://www.rfc-editor.org/rfc/rfc1217.html

Its in section 4: Jam-Resistant Underwater Communication

Re: Record-breaking neutrino is most energetic ever detected

#38

Post by h0l0cube »

A_D_E_P_T wrote: post #10
lnauta wrote: post #8

Earlier quoted context omitted.

One of the lead researchers in KM3NeT mentioned that the particle was emitting 2 horse power in light during detector transit. A typical body builder expends about 1 horse power while performing, so its 2 body builders in a single particle.

> typical body builder expends about 1 horse power while performing Close, but ackshually... Bodybuilders just oil up and pose in beauty pageants. 1 horsepower is basically one 250-pound bench press in one second. (550 foot pounds of work; the aforementioned bench press assumes a 2.2-foot stroke length.) Most bodybuilders and serious weight lifters can do that, but they can't keep it up for long.

So the neutrino is just doing a PB 1RM?

Re: Record-breaking neutrino is most energetic ever detected

#39

Post by queuebert »

GuB-42 wrote: post #25
antognini wrote: post #7

For context, 120 PeV is about 10% the kinetic energy of a ping pong ball during typical play.

Now, what will happen if you get hit by a ping-pong ball mass of 120 PeV neutrinos? 120 PeV is about 2e-16 grams, so a ping-pong ball will have about 1e16 of them. From nothing, to detectable, to lethal, to big boom? My intuition would be "detectable" but I don't know enough to do the maths. And by the way, I am using the mass-energy, not proper mass, because the question is crazy enough not to even consider what wou…

Total energy of impact would be 120 PeV x 10^16 = 120 x 10^31 eV = ~60 kilotons TNT, or 4 Hiroshimas.

So BIG boom.

Since the velocity is so close to the speed of light, you can think of this like the energy released by annihilating a ping pong ball made of antimatter.

Edit: Commenter asked what would happen if they "hit", so I'm assuming a hypothetical 100% collision. But yes to stop 1/e of a neutrino beam with normal matter, you'd need a light year of lead.

Re: Record-breaking neutrino is most energetic ever detected

#40

Post by PaulHoule »

ge96 wrote: post #33

What's faster than satellite communication? Neutrinos baby Not even sure if that's worth doing, either create/emit or use encode data into them as they fly by to be received by someone else Edit: that's cool people have tried though

Would have really been faster if this result was true

https://en.wikipedia.org/wiki/2011_OPERA_faster-than-light_n...

which was something that would have happened in

https://en.wikipedia.org/wiki/Steins;Gate

Funny the idea that the neutrino might be a tachyon never seems to go away. The best fit of OPERA results is within error bars of the speed of light but towards the superluminal side. Superluminal neutrinos of the energy they were generating with the kind of mass we expect wouldn't be going measurably faster than the speed of light.

I visited the site of this experiment

https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lar...

where the best fit for the squared mass was just a tiny bit negative but within bounds of zero. There is the classic 1985 Chodos paper

https://www.academia.edu/27606971/The_neutrino_as_a_tachyon?...

and people still keep writing papers about it

https://www.mdpi.com/2073-8994/14/6/1172

somebody is going to have to measure a positive mass squared to really put a stake in its heart.

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