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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

#71

Earlier quoted context omitted.

I've wondered the same about gravitons. Notwithstanding the need for likely-huge sensing equipment for the first N years of development...

It's not yet clear if gravitons exist at all.

Isn't that what the higgs is?

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#72
post #58

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…

Maybe we could start with processing nuclear waste though.

Having a big pile of random heavy elements can be a worse environmental issue.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#73

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.

https://www.nature.com/articles/s41567-018-0319-1

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#74

Earlier quoted context omitted.

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.

... but which instantly decay. So not interesting.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#75
post #55

Earlier quoted context omitted.

I have a hard time imagining a particle associated with the curvature of spacetime.

I had a really hard time imagining a particle associated with mass (Higgs boson)

Doesn't this simply follow from the mass-energy equivalence (the energy being that of interaction with the Higgs in this case)? Not to say that said equivalence is intuitively obvious, of course.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#76

Earlier quoted context omitted.

I think this would be impossible without truly alien materials.

Really? Seems like if we were motivated to do it, we could have a network of Earth satellite detectors in ~a century or so.

We need to put a few kilotons of extremely pure water (or maybe other transparent substance) into each satellite.

Not impossible, but likely this amount of orbital lift capacity is better used for other projects.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#77

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.

> That's even though [gravity]'s the one with the simplest equations. Aren't the equations for gravity non-linear, while the other 3 are linear?

They're linear to the first-order, but everything is linear to first order by the definition of first order.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#78
post #5

Earlier quoted context omitted.

The thing with gravity is that it is kind of easy to detect, even for a layperson, while dark energy and dark matter haven't been detected at all, by anyone, but only used as mathematical devices to make indirect measurements of large scale structures align with our models. So, it isn't only the "average man on the street" that thinks there are good reasons to put them in very different categories of understanding.

Curiously... In the way dark matter has never been detected (no particle has been found), gravity has never been detected, and in the way gravity has been detected (through its influence on the trajectories of detectable matter), dark matter has been as well.

Well, scientists would argue that general relativity (I.e. gravity the way we understand it now) does predict a lot of things really well.

Now, the problem is that its predictions fall apart at quantum scale and cosmological scale. Dark thingies are just a way to make the equations work at cosmological scale.

There's always modified gravity, which takes an alternative approach by changing the equations.

That's how they taught me 15 years ago, so give or take:-)

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#79

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.

> Unless we discover a new type of matter that interacts more strongly with neutrinos How about astrophage? :)

Amaze.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#80

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.

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