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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

#61

Post by XorNot »

gizmo686 wrote: post #46
hyperhello wrote: post #40

Earlier quoted context omitted.

It's possible that there could be an entirely different charge mechanism that works exactly like ours but they don't interact at all; but the whole premise of dark matter is that it doesn't seem to have any self-interaction outside of gravity.

The premise of dark matter is that it is something with gravity that does not otherwise interact with any of our detectors (e.g. "normal" matter); or that any such interactions are weak enough that it is plausible we have not noticed. By itself, that does not exclude the possibility of dark matter having other interactions which do not interfere with our detectors.

But it does bound it: if dark matter has self-interactions then the apparent distribution would be different. Regular matter forms stars and galaxies and all the structures we see because it can self-interact.

Since where we see dark matter mass shadows we don't see structure formation, what self interaction it may have must be very, very limited.

Re: Biggest dark matter detector spots a single weird particle

#62

Post by mr_mitm »

cogman10 wrote: post #53
cwmma wrote: post #48

Earlier quoted context omitted.

Probably not, they have a pretty good handle on why atoms decay, to the point they can predict some to be radioactive before it's actually observed to be (like Bismuth-209). Also even if something is REALLY REALLY long lasting, you can still check for the halflife by observing enough of it, they've been able to rule out proton halflives under 10^34 years (the universe is on the order of 10^10 years old) but by observ…

> they have a pretty good handle on why atoms decay Oh, they actually don't. Radioactive decay, AFAIK, is still an open physics mystery. We know it happens, we don't know why, what causes it, or if there even is a cause. We can predict factors that make it more likely. > to the point they can predict some to be radioactive before it's actually observed to be (like Bismuth-209). Right, but Xenon 124 wasn't predicted t…

Where is the mystery? Any system can spontaneously transform into a new state with a probability greater than zero unless some conservation law prevents it. In a sense it's just quantum tunneling.

Re: Biggest dark matter detector spots a single weird particle

#63

Post by Charon77 »

tomrod wrote: post #55
ajkjk wrote: post #23

Earlier quoted context omitted.

You think that people's findings should be communicated by email? that their email chains are what should go into the permanent record and be cited and printed out and included in journals and such? would you include all the quoted text in the reply-alls, or is that too much?

That's how Linux is built. Science has too many threads to do it successfully though

> would you include all the quoted text in the reply-alls, or is that too much?

Only quote the relevant part and reply to it, just like this very comment.

And Linux has a large mailing archive of various lists and threads that are searchable and available to everyone and get this: free access

Re: Biggest dark matter detector spots a single weird particle

#64

Post by stouset »

matthewdgreen wrote: post #21
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-…

This sort of thing is really useful for helping people to understand what the purpose of scientific publication is. It's not about presenting finished products to society, it's more like a Discord where you communicate new findings with other authors. Often the reason for a communication is because you found something weird, and you want other people to know about it so they can help you confirm or rule it out as bad…

Yep. Publishing like this gives a heads up to those operating similar observatories to keep an eye out for similar events. And it gives a nudge to theorists that might help them start looking in a more fruitful direction, appropriately caveated that it may be a statistical fluke.

Re: Biggest dark matter detector spots a single weird particle

#65

Post by stouset »

gizmo686 wrote: post #46
hyperhello wrote: post #40

Earlier quoted context omitted.

It's possible that there could be an entirely different charge mechanism that works exactly like ours but they don't interact at all; but the whole premise of dark matter is that it doesn't seem to have any self-interaction outside of gravity.

The premise of dark matter is that it is something with gravity that does not otherwise interact with any of our detectors (e.g. "normal" matter); or that any such interactions are weak enough that it is plausible we have not noticed. By itself, that does not exclude the possibility of dark matter having other interactions which do not interfere with our detectors.

Our observations are much more consistent with a form of dark matter which does not self-interact, or which does so incredibly weakly.

Don’t ask me how or why, but this is essentially the universal (pun intended) consensus amongst cosmologists.

Re: Biggest dark matter detector spots a single weird particle

#67

Post by terminalbraid »

stouset wrote: post #65
gizmo686 wrote: post #46

Earlier quoted context omitted.

The premise of dark matter is that it is something with gravity that does not otherwise interact with any of our detectors (e.g. "normal" matter); or that any such interactions are weak enough that it is plausible we have not noticed. By itself, that does not exclude the possibility of dark matter having other interactions which do not interfere with our detectors.

Our observations are much more consistent with a form of dark matter which does not self-interact, or which does so incredibly weakly. Don’t ask me how or why, but this is essentially the universal (pun intended) consensus amongst cosmologists.

That doesn't rule out "dark matter having other interactions which do not interfere with our detectors" Dark sector theories which include other dark particles or new particle interactions are not controversial amongst cosmologists in this space. For example there's a whole area of study around "dark photons" which would mix with our photons and interact with dark matter.

Re: Biggest dark matter detector spots a single weird particle

#68

Post by ajkjk »

Charon77 wrote: post #63
tomrod wrote: post #55

Earlier quoted context omitted.

That's how Linux is built. Science has too many threads to do it successfully though

> would you include all the quoted text in the reply-alls, or is that too much? Only quote the relevant part and reply to it, just like this very comment. And Linux has a large mailing archive of various lists and threads that are searchable and available to everyone and get this: free access

The linux developers' mailing lists are not producing anything like scientific papers...

Re: Biggest dark matter detector spots a single weird particle

#69

Post by bdamm »

ajkjk wrote: post #68
Charon77 wrote: post #63

Earlier quoted context omitted.

> would you include all the quoted text in the reply-alls, or is that too much? Only quote the relevant part and reply to it, just like this very comment. And Linux has a large mailing archive of various lists and threads that are searchable and available to everyone and get this: free access

The linux developers' mailing lists are not producing anything like scientific papers...

Kind of arrogant no? Linux kernel development mailing lists are producing something immensely valuable with a much clearer impact on economic indicators than your average scientific paper. Comparing them is hard, but it's patently absurd to say there's nothing being produced compared to scientific papers.
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