SaberTail

Joined 13 years ago

Karma
1,106
Submissions
192
Member since
Oct 17
Ex-physicist. I now make my living writing software in biotech.

Email: my username here at physicsdog dot org

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Recent submissions

Comment · 1 month ago
The contradiction between capitalism needing consumers and automating labor out of work has arisen before in the industrial revolution. The solution back then was imperialism and using the profits from the colonies to subsidize a middle class to consume things. Maybe capitalism has still got a few tricks up its sleeve, but the world is finite so you might be right.
Comment · 1 month ago
For example, Safeway (and the rest of the Albertsons stores) offer coupons that are only available online. You use them in person in the store, via the loyalty card, but you have to use their website or app to get them. Some of these get offered to everyone, but others are personalized based on whatever data they have on you.
Comment · 1 month ago
> The "Status" LED flashes some kind of code - long long, short short short. I assumed the number of flashes would correspond to the time but apparently not. We didn't have time to figure this out before we had to leave.

long-long-short-short-short is 7 in morse code. They don't say what time they tried this or if it ever changed, though, so that's just a hypothesis.

Comment · 1 month ago
If the AI wrote the article, and with no code, how do we know this even happened?
Comment · 2 months ago
They have a lot of shielding for the detector, and also if there were a significant source of neutrons they'd expect to see other evidence, both in the detector and in the separate "veto" detector that surrounds the main detector.

That's not to say it can't be a neutron, but it would be surprising if it were.

Comment · 2 months ago
Detectors like this work on exposure. They're always on (except for calibration and maintenance), waiting for events to happen. This paper was written with 2.8 tonne-years of data. That is, 4.7 tonnes of liquid xenon for a little mmore than half a year. The detector has 7 tonnes, and the 4.7 number reflects cuts they made on parts of the detector that either they don't understand as well, or have higher backgrounds.

As they better understand the detector, they can use more of that mass. They have data from it, but they just didn't use it. And they're always collecting more data, too, as time passes.

So the 3x is saying they have something like 8.5 tonne-years of data.

Comment · 2 months ago
In one sense anything that passed all their background rejection is a WIMP. To interact with a nucleus through so much matter, it's not interacting electromagnetically. The main candidate for a strong force interaction would be a neutron, and they did a lot of work to model that and eliminate it as a background. So definitionally it would be a WIMP.

They were pretty model agnostic in what they were looking for. They modeled and simulated a number of different ways a WIMP could interact with normal matter. If this is a discovery, more data will be needed to figure out the nature of that interaction and how it fits into particle physics.

But there's always a chance it's something completely new, or some extremely rare manifestation of things we already know about, but have never seen before. And even if it is WIMP, it may not be the right type of WIMP (wrong mass, or wrong interaction strength) to explain cosmological dark matter.

Comment · 2 months ago
To start with, they do a lot of work to eliminate radioactive backgrounds in the materials they're using, and they put the detector deep underground to shield from cosmic rays.

Additionally, when a particle interacts with the nucleus, the ratio of how much energy ends up as scintillation light versus ionization is different than when a particle interacts with an electron, which is most of the background processes.

Then, whatever is left, they try to model using known processes. After all that, there's one event that they can't account for. And that's what the news is about.

Comment · 2 months ago
Comment · 2 months ago
It's mostly about signal-to-noise. The drawback to those detectors is that because the nuclei are heavy, when the neutrino interacts with them, they don't end up moving very fast and so there isn't much of a signal produced in the detector. They have to be cooled to cryogenic temperatures to even have a chance of seeing a coherent scattering event above thermal noise. Yes, the interaction cross section for the neutrinos is larger, but you can't pick out individual events very easily.

The 2017 paper you linked is the first observation of the process. They had to do it statistically; there's no smoking gun event. It took them almost a year with the thing sitting next to a neutron beam to get enough statistics. With a beam, they were able to do extra noise rejection based on the beam timing. It's still a lot of experimentation and engineering work to go from that to something that can operate in a lower signal-to-noise environment.

Also, growing large scintillator crystals is a very specialized process and so they are expensive. The cost is going to limit how large you can make such a detector. You can scale up a water-based detector much more easily, and that extra mass can make up for the reduced cross section, depending on what you are trying to observe.

Comment · 3 months ago
The name is misleading. The glyphs are showing individual chord shapes. I can't write out a song using this. At best I can use this at the top of a tab to remind myself how the chords are meant to be shaped. But that doesn't appear to work much beyond the basic cowboy chords. For example, I tried 577655 which is an A major barre chord, and it didn't render. I realize a font can only do so much, but I wouldn't pay for this.
Comment · 7 months ago
I said to a few friends that the recent trailer felt like it could be for a House of Leaves movie. Different overall setting, but the "found footage" aspects, and the narrative over it, felt like they could be right out of the Navidson Record.

I don't have any real proof for this, but it feels like House of Leaves inspired a lot of the people making "found footage" and "creepypasta" stuff one the internet in the 2000s and early 2010s (SCP, Marble Hornets, Slender Man), and then that stuff came together to inspire the Backrooms.

Comment · 7 months ago
Comment · 8 months ago
The "figure out what you want to say" is key. I've started to think of LLMs, at least in a business setting, as misunderstanding amplifiers.

How many times at work have you been talking to someone else where they're using common words as jargon? Maybe it's something like "the online system" or "the platform". And it's perfectly clear to them what they mean, but everyone else in the company either doesn't know what that actually is, or they have a distorted idea based on the conventional definitions of the words. Even without LLMs in the mix, this can lead to people coming out of meetings with completely different understandings of what's going on.

My experience is few people are actually providing the relevant context to the LLM to explain what they mean in situations like this. Or they don't have the actual knowledge and are using the LLM in the hopes it'll fill in for their ignorance. The LLMs are RLHFed to sound confident, so they won't convey that they don't know what a piece of jargon means. Instead they'll use a combination of the common meaning and the rest of the context to invent something. When this gets copy/pasted and sent around, it causes everyone who isn't familiar to get the wrong idea. Hence "misunderstanding amplifier".

To the point of the article, this is soluble if people take the time to actually figure out what they are trying to convey. But if they did that, they wouldn't need the LLM in the first place.

Comment · 8 months ago
as far as MSHA is concerned it is. They take salt out of the ground to make room for the waste.

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