Jump to content

Science News Thread (for articles that don't relate to ongoing discussions)


Recommended Posts

20 hours ago, DDE said:

...Russian pro-state outlet: "Readers of The Sun criticize British authorities for inadequate response to extraterrestrial threats"

Sorry, this dead horse needs kicking.

Considering the average readership of The Sun, I'm not sure if that counts as propaganda. It may just be true :D

 

Link to comment
Share on other sites

Ars has an interesting interview with Moriba Jah, a foremost expert on space debris: https://arstechnica.com/science/2022/12/space-debris-expert-orbits-will-be-lost-and-people-will-die-later-this-decade/

Quote

Jah: I'm also pro-business in space. The thing is the manner in which we do it. At the end of the day, based on international law codified in treaties and conventions from 1967 to 1972, liability for damage and harmful interference falls squarely on the shoulders of states party to the treaty. So governments are responsible, ultimately. Companies bear no liability for their behavior. Countries do.

 

Link to comment
Share on other sites

26 minutes ago, Beamer said:

So governments are responsible, ultimately. Companies bear no liability for their behavior. Countries do.

And that's where the pesky word "regulation" comes in. Depending on who you ask, private companies exist entirely at the mercy of their parent governments, and so it's not illogical to hold the license-issuing authority accountable. But, unfortunately, this area is prone to ideological bias - "Our plucky rule-abiding private enterprise against their nefarious front for an unfriendly state who'd never hold them accountable".

Link to comment
Share on other sites

A meteorite fell in Pujiang Conty, Jinhua City, Zhejiang Province.

CCTV footage of the meteorite as it crossed the sky

image.png

The meteorite itself has been found, but the local dialect spoken by the video shooter is "an unspeakable alien language" even for me, so I won't put the source.

Add: translator in the comment who understands the local dialect said that the video shooter was saying that this was part of the meteorite she had found and that the stone weight about '3 Jin 4 Liang' (which translates to around 1700g)

one more video, she was making a video and...

Edited by steve9728
Link to comment
Share on other sites

2 probable water worlds found, Kevin Costner rejoices: https://arstechnica.com/science/2022/12/scientists-revisit-kepler-findings-learn-two-planets-are-water-worlds/

Quote

Matching the density of the two planets produces a model that has a bit over 10 percent of the planet's mass composed of water. This, however, means that about half the planet's volume is water. While some of that might be incorporated into the rocky core, it likely means a planet-wide ocean that's kilometers deep. And, unlike the icy moons, the planet is close enough that much of the water would be liquid, and the atmosphere would be filled with water vapor.

 

Link to comment
Share on other sites

Juno going for some flybys

Jupiter’s moon Io, dotted with hundreds of volcanoes, set for a close-up (nbcnews.com)

The volcano-laced surface of Jupiter’s moon Io was captured in infrared by the Juno spacecraft’s Jovian Infrared Auroral Mapper (JIRAM) imager as it flew by at a distance of about 50,000 miles July 5.

221215-Jupiter-moon-Io-al-1053-d4e8b4.jp

Now we know where Darth got that face

Link to comment
Share on other sites

Breaking news: Marketing Drones were always right, sum of everything is not necessarily 100% :D - Physicists Rewrite a Quantum Rule That Clashes With Our Universe

Quote

Unitarity, as the principle is called, says that something always happens. When particles interact, the probability of all possible outcomes must sum to 100%. Unitarity severely limits how atoms and subatomic particles might evolve from moment to moment. It also ensures that change is a two-way street: Any imaginable event at the quantum scale can be undone, at least on paper. These requirements have long guided physicists as they derive valid quantum formulas. “It’s a very restrictive condition, even though it might seem a little bit trivial at first glance,” said Yonatan Kahn, an assistant professor at the University of Illinois.

But what once seemed an essential scaffold may have become a stifling straitjacket preventing physicists from reconciling quantum mechanics and gravity. “Unitarity in quantum gravity is a very open question,” said Bianca Dittrich, a theorist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.

(OK not exactly breaking, originally printed on September 26th on Quanta Magazine, but reprinted yesterday on wired.com to a presumably larger audience).

 

Link to comment
Share on other sites

33 minutes ago, Beamer said:

Breaking news

I'm going to have to read it a second time - but I got a distinct 'QM doesn't align with LCDM... let's fudge it' vibe.

Interestingly, one of the companion articles suggests Asymmetry Detected in Distribution of Galaxies

Asymmetry Detected in the Distribution of Galaxies | Quanta Magazine

Isotropic or not?


 

Spoiler


The ΛCDM model has been shown to satisfy the cosmological principle, which states that, on a large-enough scale, the universe looks the same in all directions (isotropy) and from every location (homogeneity); "the universe looks the same whoever and wherever you are."[18] The cosmological principle exists because when the predecessors of the ΛCDM model were first being developed, there wasn't sufficient data available to distinguish between more complex anisotropic or inhomogeneous models, so homogeneity and isotropy were assumed to simplify the models,[19] and the assumptions were carried over into the ΛCDM model.[20] However, recent findings have suggested that violations of the cosmological principle, especially of isotropy, exist. These violations have called the ΛCDM model into question, with some authors suggesting that the cosmological principle is now obsolete or that the Friedmann–Lemaître–Robertson–Walker metric breaks down in the late universe.[13][21][22] This has additional implications for the validity of the cosmological constant in the ΛCDM model, as dark energy is implied by observations only if the cosmological principle is true.

 

Lambda-CDM model - Wikipedia

 

Link to comment
Share on other sites

2 hours ago, JoeSchmuckatelli said:

I'm going to have to read it a second time - but I got a distinct 'QM doesn't align with LCDM... let's fudge it' vibe.

I think it's an elegant solution to a number of problems which immediately suggests the ability for observational predictions. That gives it an edge to just about... 99% of all quantum related theories? I mean people are still talking about string theory and many worlds, which not only have failed to satisfy the latter half of that statement, but (depending on who you ask) actually state that they are inherently untestable. I'm sure there's a lot of work to be done before they get to that point (and then observations might show it's incorrect) but at least it's not principally impossibly right out of the gate.

 

Link to comment
Share on other sites

5 minutes ago, Beamer said:

still talking about string theory

Grin!

I remember getting all excited about reading that stuff in the late 80s... then M theory and then...  well, this is just weird and doesn't work... and while no one can disprove it... you can't prove it either... so maybe shelve it?

OTOH - lots of money and time have been spent on CDM, and while its a nice theory - we just can't find proof; and there's frequent handwavium whenever something doesn't align with its predictions... which makes me suspicious.*  I'm certainly not qualified to disprove or even disapprove of it... but what I don't care for is how strident a lot of people got (way back when) on the BadAstronomy boards whenever anyone posted research papers that did not conform to that dogma.  Admittedly, a lot of that hostility was directed at MOND - but what I found disquieting was how no one even wanted to allow questions about possible other explanations.

Dan Hooper's book "At the edge of Time" was great - but his evident frustration at having sought for proof of DM throughout his career was telling; he's convinced its there... but frustrated that none of the extremely sensitive experiments can even find a glimmer. (a good read, along with "Gravity's Century, by Ron Cowen)

 

*Mind you, I'm aware of all the ways that it does work and does explain some things we are seeing.

Link to comment
Share on other sites

9 hours ago, JoeSchmuckatelli said:

OTOH - lots of money and time have been spent on CDM, and while its a nice theory - we just can't find proof; and there's frequent handwavium whenever something doesn't align with its predictions... which makes me suspicious.*  I'm certainly not qualified to disprove or even disapprove of it... but what I don't care for is how strident a lot of people got (way back when) on the BadAstronomy boards whenever anyone posted research papers that did not conform to that dogma.  Admittedly, a lot of that hostility was directed at MOND - but what I found disquieting was how no one even wanted to allow questions about possible other explanations.

Well, you know, Internet fora... :D I don't think any physicist considers Lambda-CDM a complete theory, they just don't want to replace it with something that is less complete and doesn't even solve the problems that LCDM has, and that's understandable. Whenever I hear someone complain that LCDM "doesn't work" for some observational data, I am reminded of Gall's law (arguably more popular in my line of work than in physics, but it's quite universal IMO): “A complex system that works is invariably found to have evolved from a simple system that worked.”

Of course you can say MOND is trying to do exactly that, but they clearly aren't at the point yet where the system is complex enough to rival with LCDM/GR in terms of observational predictions, and AFAIK that goes for all alternative proposals. A lot of these alternative proposals are designed specifically around the shortcomings of LCDM. To me that doesn't seem like a good way to go about it. LCDM describes a lot of things we do know, and fails to explain some things we don't know. If you want to propose an alternative, it's probably a good idea to make sure it can at least describe the things we do know, and not just provide an explanation for the things we don't know. Otherwise, you're probably better off trying to extend the LCDM model rather than coming up with something that rejects it.

A lot of the 'shouting contests' in physics boil down to funding of course, and the way that is done nowadays is to a large extent driven by the nature of the post-internet world. In the old days, no matter how hard you shouted, the only ones who would hear it were your colleagues in the field who read your research papers. It wouldn't appear in the science section of the Saturday edition of your favourite printed newspaper until you had managed to convince a considerable portion of those colleagues. Nowadays all you need is a youtube account and a call to Curiosity Stream or Raid Shadow Legends for the sponsoring, and all the world will know about your ideas and have opinions about it. That's good for people like me, who don't work in the field but like to follow it as a 'hobby', but among the professionals it often seems to lead to some unsavoury discussions and animosities.

 

Link to comment
Share on other sites

This actually deserves its own post:

UniverseStructureSlice_byDanielEisenstei

Each dot in this picture, which covers about one-twentieth of the sky, represents the location of a galaxy mapped by the Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey. A statistical analysis of 1 million galaxies in the survey has found evidence of parity violation.

(Emphasis mine)

Physicists believe they have detected a striking asymmetry in the arrangements of galaxies in the sky. If confirmed, the finding would point to features of the unknown fundamental laws that operated during the Big Bang.

“If this result is real, someone’s going to get a Nobel Prize,” said Marc Kamionkowski, a physicist at Johns Hopkins University who was not involved in the analysis.

As if playing a cosmic game of Connect the Dots, the researchers drew lines between sets of four galaxies, constructing four-cornered shapes called tetrahedra. When they had built every possible tetrahedron from a catalog of 1 million galaxies, they found that tetrahedra oriented one way outnumber their mirror images.

Asymmetry Detected in the Distribution of Galaxies | Quanta Magazine

TETRAHEDRON_FIGUREbyMerrillSherman_560-D

The tetrahedron is the simplest shape that has parity, or handedness. It looks different when reflected in a mirror.

Edited by JoeSchmuckatelli
Link to comment
Share on other sites

On 12/19/2022 at 1:17 PM, kerbiloid said:

It should be a triangular prism. Usually.

Tetrahedron is the Greek platonic name for it given by Plato.  Triangular prism is correct also, but is stripped of history and is more common in places where a political attempt to strip away history has occurred.   

I enjoy following the historical threads of language and terminology and find the embedding of history (or lack thereof) in common parlance to be probably the most profoundly accessible and omnipresent history lesson in existence. It is the "blockchain" record of civilization distributed across individuals

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...