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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

#91

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.

There have been (theoretical) proposals to use them to communicate with submarines: http://www.physics.ucla.edu/~hauser/neutrino_communication_p...

> Neutrinos have many properties that would make them superior even to the extremely low radio frequencies. Because neutrinos are nearly unaffected by matter, a neutrino beam could traverse directly through the earth from the transmission site to the submarine. A directional beam would allow confidential information to be passed only to the intended recipient. Neutrino communications would also be totally jam-proof. As an additional benefit, a neutrino message could be received in the deepest of waters, leaving a submarine less vulnerable to enemy attacks.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#92
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?

I imagine like a lot of the nuclear alchemy the cost is much higher than just getting the existing material you want.

But for something like a kardashev type 2 or 3 civilization with abundant energy, it would be trivial and saves time searching for and accumulating the material? It would also be conflict free.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#93

Earlier quoted context omitted.

Unless I orient the thin edge of my thumbnail so I’m presenting the smallest possible cross section towards the sun!

I'm not embarrassed to admit I just tried this. I will walk around with thumbnail oriented thusly and make my observations. Perhaps the origin of the thumbs up? If anyone asks I will casually explain that I'm reducing my thumbail cross section to minimise the unknown effects of solar neutrinos.

If you can detect neutrinos below your thumb, I’m officially impressed!

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#94
post #43

Earlier quoted context omitted.

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

The same problem is faced by optical communication during the day with the sensors exposed to sunlight. SNR can be increased a fair bit with even slight directionality. If sensitivity of detection is one day high enough, I think it would be theoretically possible to obtain directional information about neutrinos, by building a whole network of sensors and synthesizing an aperture.

For conventional electronic and optical purposes this isn't a huge deal. You "just" modulate the signal to be transmitted onto a fixed-frequency carrier, and have the receiver ignore everything that's not a sideband of that particular carrier frequency.

It's one of those cases where "just" really does apply. IR remote controls work this way, using a slow bitstream to key a 40 kHz carrier that drives the IR LED. Scientific applications that need even greater sensitivity can take advantage of the fact that the expected phase of the carrier is known as well as its frequency. Devices called lock-in amplifiers are used to run a wide variety of experiments and processes using that principle.

Doing this stuff with neutrinos rather than photons, however, is one of those * * * * * exercises that the textbook authors put in as a joke.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#95
post #85

Earlier quoted context omitted.

It’s a rather novel and very strange to say that something hasn’t been detected because you haven’t found a particle responsible for it, even though our whole existence and all our everyday experiences are grounded in it. Gravity is the effect. It’s there. Whether you explain it with force carrying particles or the geometry of space time won’t change it. Dark matter is one hypothetical explanation of an effect (or ra…

> In other words, gravity and dark matter have very different ontological status. I get what you're saying, but you can make them the same again by transposing Dark Matter to Dark Matitation, by analogy to Gravitons->Gravitation.

No, they are still not the same. If I understand you correctly, you are saying that Dark Matter would correspond to Gravitons. But that would just prove my point, because Gravitons is just a hypothetical explanation of gravity, in the same way as Dark matter is a hypothetical explanation of, e.g., the rotation profiles of galaxies.

(And here we have so far left out that the only reason Dark matter makes sense is because we are trying to not have to modify our current understanding of gravity.)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#97
post #52

Earlier quoted context omitted.

Relevant xkcd: https://xkcd.com/1489/ The mouseover-text is the important bit: "Of these four forces, there's one we don't really understand." "Is it the weak force or the strong--" "It's gravity." That's even though it's the one with the simplest equations.

Is that an attempt to appeal to authority?

Worse than that: an appeal to the reader’s sense of humour.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#98

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.

Do neutrino's have a wavelength? If not then there'd be one channel and almost no way to prevent crosstalk.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#99

Earlier quoted context omitted.

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

[deleted]

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#100
post #61
post #14

Earlier quoted context omitted.

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”?

The mass of the neutrinos is not known with any reasonable precision.

It is known only that it is not likely to be zero (because the commonly accepted explanation for the so-called neutrino oscillations requires a non-null mass, even if there are alternative theories) and that it must be small because various experiments have determined some upper limits for the masses of the 3 kinds of neutrinos.

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