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Biggest dark matter detector spots a single weird particle

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Re: Biggest dark matter detector spots a single weird particle

#121

Post by ourmandave »

kypro wrote: post #118
jesse_dot_id wrote: post #94

Earlier quoted context omitted.

Probably never. We've only mapped like 29% of the seafloor, actually explored like %5 of it, and we've barely pierced the earth's crust.

I never understood why people cite this as a demonstration for how little we humans understand about our world. The reason we haven't mapped the seafloor is because why would we? It's like arguing we know nothing about biology because we've only sequenced the genome of a fraction of humans or something. It's not that we can't do it, the reason we haven't done it is because there's no good compelling reason to do it.…

I'm a complete layman but it seems like we've got a long way to go and history will look back on us like we do on Newtonian Physics.

Just given dark matter and energy, things the standard model doesn't answer, and our evolving tools (e.g. Grace telescope, etc.).

Re: Biggest dark matter detector spots a single weird particle

#122

Post by GuB-42 »

SaberTail wrote: post #5

I read their preprint[1] and they did a thorough job. They investigated a number of the things I'd suspect if I were looking for mis-reconstructed events or weird backgrounds. So it's certainly interesting! That said, particle physics history is full of 3 sigma particle "discoveries" that disappeared with more data. They're collecting more, so hopefully we'll learn more in a few more years. [1] https://lz.lbl.gov/wp-…

> That said, particle physics history is full of 3 sigma particle "discoveries" that disappeared with more data.

The idea is that because 3 sigma means a ~1/1000 chance of the thing being explained by random chance, 1 in 1000 experiments will produce a bogus 3 sigma result, and we do many thousands of experiments.

Re: Biggest dark matter detector spots a single weird particle

#123

Post by narnarpapadaddy »

retsibsi wrote: post #120
birdland wrote: post #99

Earlier quoted context omitted.

I don't think Gödel is necessarily what is meant here, there are very good information theoretical(and other) reasons you can never describe a system with truly perfect accuracy. The map has to be become the territory for genuinely perfect accuracy.

> The map has to be become the territory for genuinely perfect accuracy. Why couldn't the territory be losslessly compressible?

The currently accepted answer to that is “the territory appears to be randomized” (quantum mechanics)

Re: Biggest dark matter detector spots a single weird particle

#125

Post by retsibsi »

narnarpapadaddy wrote: post #123
retsibsi wrote: post #120

Earlier quoted context omitted.

> The map has to be become the territory for genuinely perfect accuracy. Why couldn't the territory be losslessly compressible?

The currently accepted answer to that is “the territory appears to be randomized” (quantum mechanics)

Makes sense, but is it relevant to the upthread claim that "All provable models (theories, explanations) that we have, or could have, are by definition wrong or incomplete"? (Not being rhetorical and snide here, I'm curious and aware I may be missing something.)

If reality has irreducible randomness (an open question afaik), and we're talking about theories and explanations (so we're not necessarily trying to describe the actual state of every particle in the universe, but only the rules governing their interactions), couldn't we have a complete, correct theory that was much smaller than the universe and contained terms for the random elements?

There would always be the possibility that it would turn out to be wrong, but it could be complete and correct, so it seems like the original claim must depend heavily on the word 'provable' and not on the impossibility of describing a system via a map smaller than the territory.

edit: but also, surely 'the territory is randomized' is a contingent physical fact, and not a necessary truth of information theory. Until we know for sure that there is irreducible randomness, we can't know that the information content of the universe (including the actual state of all particles at all times) isn't losslessly compressible, right?

Re: Biggest dark matter detector spots a single weird particle

#126

Post by hershkumar »

scotty79 wrote: post #95
hershkumar wrote: post #84

Earlier quoted context omitted.

I actually saw one of the authors present the data yesterday, one of the audience comments was indeed that this could be explained by an astrophysical neutrino striking the detector (all other neutrino sources have energy thresholds much lower than the detected data), but the data on astrophysical neutrinos is sparse (in part why detectors like IceCube exist), so I believe the argument is that the chances that an ast…

Thank you very much for this first hand info. One might argue that chances of theoretical particle existing and showing up are at least as negligible.

I think the WIMP interaction process via the models they tested and the data on astrophysical neutrinos from other detectors gives at least several(?) orders of magnitude of separation in the rate at which each would strike the detector. Of course this would not fully rule out the possibility that it is a stray neutrino.

Re: Biggest dark matter detector spots a single weird particle

#127

Post by kypro »

ourmandave wrote: post #121
kypro wrote: post #118

Earlier quoted context omitted.

I never understood why people cite this as a demonstration for how little we humans understand about our world. The reason we haven't mapped the seafloor is because why would we? It's like arguing we know nothing about biology because we've only sequenced the genome of a fraction of humans or something. It's not that we can't do it, the reason we haven't done it is because there's no good compelling reason to do it.…

I'm a complete layman but it seems like we've got a long way to go and history will look back on us like we do on Newtonian Physics. Just given dark matter and energy, things the standard model doesn't answer, and our evolving tools (e.g. Grace telescope, etc.).

To expand a little, my prediction is based on the fact that we can already explain the vast majority of physical processes with extreme procession. The things we can't explain tend to be very small, very large or very quick. But there's almost nothing in our day to day lives that we can't explain anymore.

This means that today to make new discoveries we tend to have to invest huge sums of money and build experiments that we'll increasingly struggle to scale significantly beyond. For example, maybe humans could just about build something 10x the size of the LHC if we really wanted, but 100x seems near-impossible. Maybe we can build slightly larger telescopes, but again, this is becoming harder due to the scale we're already working at.

So while I agree there's probably lots of physics out there to discover, the physics we humans are actually likely to be able to discover is rapidly diminishing. And the physics which is likely to revolutionise our daily lives is presumably even smaller more due to scale and energy levels where mysteries remain.

But ultimately who knows, this is just my opinion – an opinion I'm being downvoted for because apparently HN discussions these days are a place for us circlejerk around the consensus view rather than discuss differences in opinion.

Re: Biggest dark matter detector spots a single weird particle

#129

Post by I_am_tiberius »

lirolero wrote: post #119
I_am_tiberius wrote: post #81

i have zero knowledge of physics, but I just can't believe something like dark matter exists. My intuition is that some math just isn't correct and falls apart at the scales of the observable universe. No idea what equations are used for getting to the reslut of having 85% unexplained matter in the universe, but I really assume there's just a constant missing or our math in general just inaccurate or not considering…

> i have zero knowledge of physics > My intuition > I really assume hmmmm

I used these phrases to make sure nobody takes it too serious, as it's only my intuition, as written.

Re: Biggest dark matter detector spots a single weird particle

#130

Post by narnarpapadaddy »

retsibsi wrote: post #125
narnarpapadaddy wrote: post #123

Earlier quoted context omitted.

The currently accepted answer to that is “the territory appears to be randomized” (quantum mechanics)

Makes sense, but is it relevant to the upthread claim that "All provable models (theories, explanations) that we have, or could have, are by definition wrong or incomplete"? (Not being rhetorical and snide here, I'm curious and aware I may be missing something.) If reality has irreducible randomness (an open question afaik), and we're talking about theories and explanations (so we're not necessarily trying to describ…

The “elements for randomness” are carve-outs for the parts of territory the map can’t contain. The more granular the map, the larger relative proportion that falls into that set. Nobody can predict the layout of my basement from a globe of the world.

We know with a high degree of certainty the universe contains things we can’t predict or observe, see Bell’s Theorem.

“Truth” doesn’t exist outside reality. There’s no substrate to hang it in. Information theory is likewise a subset of the territory, part of the universe, not apart from it. For these things to exist independently, you need something other than or bigger than the universe to put them in. If such a thing existed, sure, from that perspective maybe a lossless compression could exist. But that’s a metaphysical argument.

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