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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

#101

Post by godelski »

ForHackernews wrote: post #91
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.

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 directio…

There's also research into using neutrinos as probes to detect things in the earth (oil, mineral deposits, etc). Different materials have different neutron absorption rate. Obviously this is pretty hard to pull off and expensive, but possible.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#102

Post by hungryforcodes »

zodiac wrote: post #53
hungryforcodes wrote: post #46

Earlier quoted context omitted.

As opposed to how we communicate now globally?

Communication via EM waves travel around the earth, not through it. (eg radio waves, fibre optic cables, satellite...)

But it's at pretty near the speed of light and how would there be an advantage to doing it the way the GP says?

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#103

Post by chasil »

make3 wrote: post #88
chasil wrote: post #40

Earlier quoted context omitted.

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."

so 30

At the maximum.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#104

Post by steve76 »

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!)

Nothing goes through you like air through your screen door or water out your faucet. What you are made of is the medium of interaction. The outside of your atoms stays the same while the stuff on the inside interacts. Conduction and convection act with just space mediums like air and water. Electromagnetic radiation acts with space mediums and time mediums. Nature does this because it has no mind. It does things as easy and lazy as possible without the need to make sense.

When you do the double slit experiment with an interference pattern, little bits of matter are not emitting. The light bulb filament and the projection screen are using their own internals as a medium of interaction. They're called particles because they have a definite start and a definite end. The temperature knob sticks while the visible color frequency stays the same. With neutrinos, the atom is staying the same temp and color, but it's loosing mass. Nature can do this as well as a bunch of other things because once again, it has no mind.

Why this matters in the real world:

There's a lot of things held back because of medical ethics. Porcine organ transplants for one. We don't know what diseases would occur in the real world. Genetics are today's microprocessors. Won't be surprised to see organic pharmaceuticals to follow the typewriter. It would be really nice to predict genetic mutations with a really good measurement of the sun.

It would be even better to control them with absolute certitude. Emit a particle beam around the earth. Interact it with a leaky heart valve, blood in the brain, a tumor, or the cellular mitosis of a porcine organ transplant like a really good radiation machine hooked up to an antennae. The earth sees tissue bonded together with hydrogen bonds at 98.6 degrees F. The universe sees tiny little bits of quark matter and sucks it right out in a beam of plasma vapor. It would negate a lot of ethical concerns and make them trivial. Humans won't be betting on that we covered all our bases. We would have built something very real outside of nature.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#105

Post by alok-g »

ericbarrett wrote: post #56
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

Yea, this. 100,000,000,000 solar neutrinos pass through your thumbnail every second. This number is not substantially different at night, either.

What would be the number of photons falling per second on the same? :-)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#106

Post by ericbarrett »

alok-g wrote: post #105
ericbarrett wrote: post #56

Earlier quoted context omitted.

Yea, this. 100,000,000,000 solar neutrinos pass through your thumbnail every second. This number is not substantially different at night, either.

What would be the number of photons falling per second on the same? :-)

Good question! I can't find a truly authoritative source, but a few calculations on the web put photon flux at the earth's surface at 10^21/m^2/s, give or take. Assuming your thumbnail is one square centimeter, that would be 10^17 photons per second, or 100,000,000,000,000,000, but only during the day :)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#107

Post by alok-g »

ericbarrett wrote: post #106
alok-g wrote: post #105

Earlier quoted context omitted.

What would be the number of photons falling per second on the same? :-)

Good question! I can't find a truly authoritative source, but a few calculations on the web put photon flux at the earth's surface at 10^21/m^2/s, give or take. Assuming your thumbnail is one square centimeter, that would be 10^17 photons per second, or 100,000,000,000,000,000, but only during the day :)

Interesting! So much higher than for neutrinos.

One follow up question. When reading about low-light cameras, the number of photons per pixel seem much smaller. I guess the following factors are involved:

Several orders of magnitude reduction under low light.

Pixel area likewise much smaller than thumb.

Exposure time less than a second.

Visible light vs. all spectrum.

Well, the question: Do the numbers fit? :-)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#108

Post by zodiac »

hungryforcodes wrote: post #102
zodiac wrote: post #53

Earlier quoted context omitted.

Communication via EM waves travel around the earth, not through it. (eg radio waves, fibre optic cables, satellite...)

But it's at pretty near the speed of light and how would there be an advantage to doing it the way the GP says?

Let the radius of the earth be R. Say you want to send a message from the north pole to the south pole.

If you use radio waves that travel around the earth, the shortest distance they can travel is πR ≈ 20,000km.

If you use neutrinos that travel through the earth, the shortest distance is 2R ≈ 12,700km.

So the advantage is about 7,300km (or in time units, 25ms ≈ 7,300km / (the speed of light))

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#109

Post by astrange »

Ma8ee wrote: post #95
whatshisface wrote: post #86

Earlier quoted context omitted.

> 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 beca…

Well, one reason dark matter is winning over modified gravity theories is that there seem to be some galaxies that don't have dark matter. So MOND needs more special pleading there, unless the observations are wrong.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#110

Post by hungryforcodes »

zodiac wrote: post #108
hungryforcodes wrote: post #102

Earlier quoted context omitted.

But it's at pretty near the speed of light and how would there be an advantage to doing it the way the GP says?

Let the radius of the earth be R. Say you want to send a message from the north pole to the south pole. If you use radio waves that travel around the earth, the shortest distance they can travel is πR ≈ 20,000km. If you use neutrinos that travel through the earth, the shortest distance is 2R ≈ 12,700km. So the advantage is about 7,300km (or in time units, 25ms ≈ 7,300km / (the speed of light))

Fair enough, your calculation seems valid. But my point still stands -- are we going to build enormous LHCs all over the world to get a (maximum) 24 millisecond advantage in global communications via neutrinos?!
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