And these are the massive tanks used to detect them

Irvine-Michigan-Brookhaven Detector: Located in an abandoned salt mine, this detector contains 2.5 million gallons of ulta-pure water. To give an idea of the scale of the tank, the object in the middle of the tank is a diver.  Joe Stancampiano via National Geographic
Of all the subatomic particles that make up matter, neutrinos are the smallest. So small, in fact, that a billion neutrinos pass through your body every second without hitting a single atom. However, a new study postulates that some ancient neutrinos, born shortly after the Big Bang, may now be as large as some galaxies.

The study, first reported by National Geographic, claims that as the universe expanded, the neutrinos generated by the Big Bang stretched along with the fabric of space-time. Now, after being distorted by 13.7 billion years of cosmic expansion, those original neutrinos could be as large as ten billion light years across.

Unfortunately, those predictions bump up against the limits of modern physics. All of the equations dealing with neutrinos are calculated with the assumption that each particle is smaller than an atom. Those equations cease to make sense when applied to a particle larger than an entire galaxy.

Additionally, designing an experiment to look for these super neutrinos would be incredibly difficult. Super neutrinos contain ten billion times less energy than regular neutrinos, which themselves are so hard to detect that for decades physicist called them "the ghost particle."

To detect those elusive particles, scientists build giant tanks filled with super pure water and lined with photo-amplifying detectors. Every once in a while, one of the billions of neutrinos streaming through the tanks strikes a water molecule. That collision causes the water molecule to emit a photon, which is then picked up by one of the detectors that line the tank. To isolate the detectors from interference, scientists built the tanks deep beneath the ground in old mine shafts, or float them above the Earth on weather balloons. To get an idea of what these detectors look like, and to see the sheer size of some of the tanks, check out this gallery of important neutrino detectors around the world.

[via National Geographic]

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6 Comments

I think scientist pull this stuff out they're a$$... that's just my opinion.

It's an interesting thought, but it would seem awfully difficult to assess even with these super tanks. The incidence of collision is so rare for the tinies. As for the new extremes -- apparently they almost don't leave a mark.

Seems a similar task to the old saw about sorting pepper from fly droppings while wearing boxing gloves. Possibly blindfolded as well.

Good luck to them

"I think scientist pull this stuff out they're a$$... that's just my opinion."

The stuff talked about in this article is real, and wasn't pulled out of anyone's arses. They're real concepts, real theories, real science and mathematics. Do some research into subatomic particles, and neutrinos, and you'll understand this article more.

cookiees453:

Did you read the article?
Neutrinos come in 3 flavors, and none of them are "10 billion light years across", which is what the article states.

"The study, first reported by National Geographic, claims that as the universe expanded, the neutrinos generated by the Big Bang stretched along with the fabric of space-time. Now, after being distorted by 13.7 billion years of cosmic expansion, those original neutrinos could be as large as ten billion light years across."

Every Atom in this universe(Atoms are made up of particles)was created during the big bang.
Since it has been proven that space in the universe is uniform, every particle must have expanded at the same rate.
How can you have different sized particles, in a uniform universe?

"Every Atom in this universe(Atoms are made up of particles)was created during the big bang."
Not quiet correct.
The fundamental forces of the universe came about from the Big Bang, not atoms. These forces brought about fundamental particles like quarks and neutrinos, which in turn brough about protons, neutrons, and electrons. Which then formed hydrogen. The hydrogen fused to form helium. The helium and hydrogen gravitated together to form stars, and from the stars came about the heavier atoms on the periodic table.

"Since it has been proven that space in the universe is uniform, every particle must have expanded at the same rate."
Hardly correct.
Space is far from uniform. Anything with mass exerts gravity, which in turn distorts space. There are clumps of mass everywhere in the universe, and they are all distorting space.
The measurement of cosmic background radiation showed that even at its earliest stages, the universe had parts of low enegery density and high energy density and most definitely not uniform.

"How can you have different sized particles, in a uniform universe?"
We have different sized particles now. Electrons are smaller and protons, and quarks smaller still.

Before you claim that "scientist pull this stuff out they're a$$" think about how the scientific method works and the checks and balances inherent in it. Think how those checks and balances make it very hard for people to just make stuff up. Finally, I suggest you read up on quantum mechanics and wave/particle duality.

Lastly, it might be advantageous for you to reconsider how literal one should take the hype-making scientific headlines from a popular publication like National Geographic.

aadailey I think it's important that we remember that this is only a theory. None of this has actually been proven but could possibly be sometime in the near future. Let's wait to share our opinions until the truth comes through.

"Since it has been proven that space in the universe is uniform, every particle must have expanded at the same rate.
How can you have different sized particles, in a uniform universe?"

This is like saying all apples are the same size. It's important to look at all the factors affecting different particles. Closeness to sources of heat may have have huge impacts on the size of objects.



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