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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

#81

Earlier quoted context omitted.

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.

This is important because… line of sight has somehow stymied us? I feel like quantum entangled communication would be a better direction to head. Not that they’re mutually exclusive development paths.

(un?)fortunately quantum entanglement cannot be used to send information any faster than classical communications. Entanglement is a good way to share bits for encrypting secrets, but you still need to be send entangled photons over a <c channel like a fiber optic or microwave cable.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#83

Earlier quoted context omitted.

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.

There are definitely unstable superheavy elements that have never yet been produced, or at least detected, but the interesting prediction (widely accepted, but far from proven) is that there are some stable ones.

[0] https://en.wikipedia.org/wiki/Island_of_stability

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#84

Earlier quoted context omitted.

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

Isn't that what the higgs is?

No. The higgs is a field that gives some elementary particles themselves (the W and Z bosons) mass, but doesn't necessarily say anything about gravity or how gravitic 'force' is transferred.

There was a lot of media hype about 'the god particle' that doesn't really translate into reality. I've said this in another comment, but if you add up the mass of the constituent quarks of a neutron, you get approximately 1% of a neutron's mass. The majority of the mass comes from interactions with strong nuclear force which are mediated by gluons, which are themselves massless.

There is no current agreed upon understanding of quantum gravity or if gravitons exist. I think the big contenders right now are String Theory (which seems to be having issues progressing in a way that is useful) and loop quantum gravity, but there are a lot more theories than that.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#85
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.

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 rather several). It’s possible to find another explanation for the same phenomena without changing the phenomena.

In other words, gravity and dark matter have very different ontological status.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#86
post #85

Earlier quoted context omitted.

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.

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.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#88
post #40

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.

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

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#89

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.

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.

Re: Physicists detect signs of neutrinos at Large Hadron Collider

#90

Earlier quoted context omitted.

> seems like a lame excuse for saying “we don’t know”. Dark matter/energy aren’t excuses, they’re labels for things that behave like matter and energy but whose nature is unknown.

Well, dark matter at least to this layperson’s eye a label for observations that are most easily explained by matter, which is not quite the same as a “thing that behaves like matter”.

Not exactly. Dark matter might reasonably considered a label for observations that are most easily explained by matter that only interacts with anything gravitationally. That’s really a quite strange property compared to all the other matter we see, but it does seem to explain a lot of things rather well.
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