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submitted 7 hours ago by Delta_V@lemmy.world to c/space@mander.xyz

...New research examines the issue. It's titled "The Life and Death of Stars That Capture Primordial Black Holes," and it's available at arxiv.org...

...When a star captures a PBH, the PBH finds its way to the stellar core. Once there, it accretes material from the star's interior, having a dramatic effect on the star's evolution. "The resulting object, a “Hawking star”...

There are two diverging paths post engulfment, and both are terminal...

It's all about disk formation, which is governed largely by angular momentum. Above a certain threshold, accretion is rapid, and powerful feedback destroys the star. If accretion is slow and steady, the Hawking star can survive...

The quiet terminal branch potentially produces gravitational waves (GWs). While the explosive branch leaves behind a low-mass, rapidly spinning BH..."Any future GW detection of a compact binary containing a subsolar or otherwise anomalous low-mass BH would be a striking signature of nonstandard compact-object formation."

The remnants from both branches are valuable probes of PBH. "Their rates, environments, and electromagnetic signatures could constrain the PBH contribution to dark matter," write the authors...

214

Commonwealth Fusion Systems (CFS) has verified the core plasma physics assumptions for its upcoming ARC fusion power plant following a peer-reviewed study published in the Journal of Plasma Physics.

The research confirms the ARC reactor design aligns with known physics, allowing the company to shift its focus toward detailed hardware engineering...

According to the validated models, the ARC plant will produce approximately 1.1 gigawatts (GW) of fusion power to generate 400 megawatts (MW) of net electricity for the grid...

CFS engineers are using this simulation framework to optimize upcoming design iterations, adjusting dimensions like tokamak width and divertor length to refine reactor performance before manufacturing begins.

[-] Delta_V@lemmy.world 2 points 1 day ago
[-] Delta_V@lemmy.world 22 points 2 days ago

H A U L I N G A S S ! ! !

Each is moving at ~6% of the speed of light!

69
submitted 2 days ago by Delta_V@lemmy.world to c/space@mander.xyz

...the two black holes orbit one another every 121 days. Their separation is roughly 250 to 540 times the Earth-Sun distance...

3
submitted 3 days ago* (last edited 3 days ago) by Delta_V@lemmy.world to c/Science@europe.pub

...In the new study, the researchers also found signs in the same set of samples of an extended fungal bloom tens of thousands of years before the asteroid impact. This coincides with intense volcanic activity in what is now India and supports the idea that volcanism was a factor in the mass extinctions in that period.

Fungal surges are presumably due to the availability of dead plants and animals as food sources following disasters and disruptions...

“If you ask most people what killed the dinosaurs, they’ll say it was that asteroid, but our fungal microfossil-based results suggest that the world already had been undergoing a cataclysm when the asteroid struck,”...

[-] Delta_V@lemmy.world 8 points 3 days ago* (last edited 3 days ago)

The paper linked to in the article says the thrusters have a specific impulse of 600s, and a thrust-to-power ratio of about 50 mN/kW.

Compared to the xenon ion thrusters used on the Dawn spacecraft, these new multi-mode thrusters produce more thrust, but are significantly less efficient. Dawn's thrusters have a specific impulse of 3,100s and a thrust-to-power ratio of about 36 mN/kW.

Even so, it means satellites can be built with one small fuel tank that can power high efficiency electrospray thrusters to make slow maneuvers, or use the same fuel as a monopropellant to quickly get out of (or into) the way of something. ASCENT monopropellant thrusters can have a specific impulse slightly better (240 Isp) than traditional hydrazine monopropellant thrusters (235 Isp).

21
submitted 3 days ago* (last edited 3 days ago) by Delta_V@lemmy.world to c/space@mander.xyz

...The key to the new system is a special propellant that can power both chemical and electrical thrusters...

...a type of “green monopropellant” originally developed by the U.S. Air Force for use in chemical propulsion in space can also effectively power tiny “electrospray” thrusters. Electrospray thrusters are dime-sized rockets that use electric fields to charge up a liquid propellant’s particles, which are then shot into space as a thrust-generating spray...

128

The Justice Department’s $1.776 billion “anti-weaponization” fund, which would pay out public money in compensation for alleged overreach in federal prosecutions, including for the insurrectionists who stormed the Capitol on January 6, 2021, has been accurately described as one of the most nakedly corrupt actions in American history. It would give a tacit endorsement from every American taxpayer to the notion that the Capitol Riot’s only transgression, for example, came from those who tried to punish its perpetrators for attempting to halt the outcome of an election...

...if a judge can be convinced that this fund, established with no transparency and no congressional or judicial oversight, which emerged from a lawsuit between a sitting president and his own government, and is arguably contrary to the purpose of the Judgment Fund from which it derives authority, is an unconstitutional scheme to defraud the government by its very structure, then anyone can sue to recoup the money, and then some, under the False Claims Act of 1863...

...Anyone found guilty of a false claim must not only pay back the ill-gotten funds, but three times the amount in damages. That means that anti-weaponization fund recipients would risk having to pay much more back in the future, while going through years of litigation. Debts incurred by FCA violations are not even dischargeable in bankruptcy...

62
submitted 1 week ago by Delta_V@lemmy.world to c/space@mander.xyz

...That something has been named Phoebe. And working out what it actually is turns out to be one of the most intriguing puzzles in modern astronomy. The phenomenon at the heart of the story is called gravitational microlensing and it’s one of the most elegant predictions of Einstein's general theory of relativity. When a massive compact object passes between us and a distant star, its gravity acts like a lens, briefly magnifying the star's light in a very characteristic way. The shape of the brightening is distinctive and entirely unlike anything produced by a variable star, a flare, or an asteroid...

The team calculated the probability of the lensing object belonging to each possible population — Milky Way stars, Large Magellanic Cloud stars, or the dark matter halo between and around them. The dark matter halo wins by a factor of 100,000. Phoebe is five orders of magnitude more likely to be a dark matter object than anything associated with normal stellar matter...

40

Puerto Rico’s representative in Congress and four other members of the House of Representatives have asked the Department of Justice’s Office of the Inspector General to investigate why a federal probe into a prison drugs-for-votes scheme was abandoned after the 2024 elections...

Their request follows a ProPublica investigation that published earlier this month detailing how prosecutors had uncovered a drugs-for-votes scheme being run by a violent gang in Puerto Rican prisons and were deep into looking at whether now-Gov. Jenniffer González-Colón or her campaign were involved. In the days following President Donald Trump’s election in 2024, as prosecutors prepared the indictment, they were told by supervisors in the U.S. Attorney’s Office for the District of Puerto Rico to exclude the voting-related charges against inmates and prison staff, four sources with knowledge of the investigation told ProPublica. Then, once Trump took office, they were told to abandon the probe into potential political ties entirely, the sources said.

In their letter, the members of Congress urged the inspector general to examine the Justice Department’s decision to not pursue charges related to election fraud “despite reported findings and evidence.” They added that the failure to further investigate contradicts the Trump administration’s “repeated emphasis on prioritizing election integrity and election security as federal enforcement priorities,” in addition to deeming drug traffickers threats to public safety and democratic institutions...

13

...While conventional LED‑based visible light communication (VLC) systems typically operate over only a few meters, the novel photonic engine can move data over 1.2 kilometers...

...“This work also provides compelling experimental support for the application of laser lighting in scenarios such as drone logistics and low‑altitude air travel,” said Xia...

...Scientists revealed that previously researchers have faced barriers to developing 6G technology, including the need for ultra-dense base stations with high energy and infrastructure costs, as well as challenges in combining high-performance lighting materials and high-speed photodetectors into compact devices that can be mass-produced at low cost...

...6G networks built into future smartphones and other objects such as streetlamps would not only allow information to move through networks an order of magnitude faster–they would be able to “see,” “hear,” and “think,” detecting people and objects and their subtle movements...

124
submitted 2 weeks ago by Delta_V@lemmy.world to c/world@lemmy.world

When people think about the Strait of Hormuz, they think about oil tankers, LNG carriers, naval escorts, insurance premiums, and the price of gasoline. They generally do not think about yellow piles of sulfur beside gas plants, phosphate fertilizer complexes, or the acid circuits that keep copper and nickel processing running. They should. The current sulfur price spike is not just another commodity-market twitch. It is a preview of a future in which the cheap sulfur system created by oil and gas cleanup is much smaller, while much of the demand for sulfur remains...

For roughly fifty years, sulfur has been cheap for a strange reason. Oil refineries and sour gas plants had to remove it anyway. Sulfur in fuels is a pollution problem. Regulations forced the oil and gas industry to take sulfur out of refined products and gas streams, and the industry recovered it as elemental sulfur. The sulfur was not the main product. It was the cleaned-up contaminant. That is a very different cost structure from opening a mine, building a roaster, managing residues, and producing sulfur deliberately...

The old low-price regime put sulfur in the $50 to $150 per ton range for long stretches. That world was built on fossil byproduct abundance. A managed transition world might put sulfur in the $250 to $350 per ton range. A structurally tighter oil and gas-light world could easily live in the $400 to $600 per ton range. Regional crises, shipping disruptions, export restrictions, or sudden HPAL nickel demand can push sulfur into the $800 to $1,200 per ton range. The point is not that every future year looks like a crisis. The point is that the old fossil byproduct floor is unlikely to be the future floor...

The logistics problem is the part that deserves more attention. Today’s model works because elemental sulfur moves better than sulfuric acid. A fertilizer producer can import sulfur, burn it on site, integrate the acid plant . . . and ship finished fertilizer...

That means the future sulfur constraint is geographical as much as chemical. The winners are likely to be integrated hubs with two or three of the required pieces in the same place. Phosphate rock plus sulfur access plus port logistics is powerful. Smelter acid plus local mining demand is powerful. Pyrite waste plus acid demand plus permits can be powerful. A lonely inland fertilizer plant that depends on imported acid is not powerful. It is exposed...

Policy makers should be paying attention because sulfur sits in the awkward space between agriculture, mining, trade, and decarbonization. Countries should map sulfur and sulfuric acid dependency. They should identify where smelter acid, pyrite, tailings recovery, phosphate fertilizer, and mineral processing can be linked in real industrial hubs. They should stress-test fertilizer and critical-mineral projects against sulfur prices far above the old fossil byproduct norm...

...Modern agriculture and mining were built in part on cheap sulfur from oil and gas. As the world moves away from oil and gas, sulfur does not disappear, but the cheap arrangement does. The future price of sulfur is unlikely to be the old $50 to $150 per ton world. It is more likely to sit structurally closer to today’s stressed market than most fertilizer, mining, and policy models assumed a few years ago. The sooner that is treated as a supply-chain design problem instead of a temporary commodity spike, the less painful the adjustment will be.

167
submitted 2 weeks ago* (last edited 2 weeks ago) by Delta_V@lemmy.world to c/world@lemmy.world

...Trump also suggested during the high-level meeting with Xi Jinping that the US, China and Russia should join forces to challenge the International Criminal Court, noting that their interests align.

26
submitted 3 weeks ago by Delta_V@lemmy.world to c/politics@lemmy.world

The question of why the U.S. government began a war with Iran is unsettled. The ostensible reasons, blocking Iran from developing nuclear weapons and protecting Iranians’ human rights, are not enough. Iran’s agreement not to build a nuclear arms program was in force...

...a U.S. government that so easily tolerates human rights abuses within the United States and in certain allied nations would seemingly have little zeal to fight Iran on that account, unless there were other inducements.

Strategic considerations as to U.S. economic sustainability and U.S. economic and political power in the world very likely impelled nervous U.S. decision-makers to start a war...

...The effective closure of the Strait of Hormuz might not be a strategic “mistake,” but rather a deliberate feature of the conflict...

...The argument is that the blockade of the straits is a deliberate move by Washington to choke off China’s energy “lifeline” and, in doing so, halt its geopolitical rise...

...“Because oil was and is so fundamental to nearly every industry, the ‘petrodollar’ became ubiquitous, and the dollar became the cornerstone of the global economy.” To preserve the petrodollar arrangement and predictability of the dollar’s value becomes a principal objective of this war...

[-] Delta_V@lemmy.world 73 points 4 weeks ago

sloppy/paste

[-] Delta_V@lemmy.world 84 points 5 months ago

Every once in a while, declare sausage. It confuses the hell out of your enemies.

--Rule of Acquisition #76

[-] Delta_V@lemmy.world 160 points 7 months ago

"I have never wished a man dead, but I have read some obituaries with great pleasure."

--Abraham Lincoln

[-] Delta_V@lemmy.world 74 points 7 months ago

The purchase price was historically low due to the libelous accusations of acetaminophen causing autism.

Investing in corruption pays off bigly when Republicans manage to ooze their way into office.

[-] Delta_V@lemmy.world 168 points 8 months ago* (last edited 8 months ago)
[-] Delta_V@lemmy.world 74 points 11 months ago

The eggs are from these flappy guys:

[-] Delta_V@lemmy.world 143 points 1 year ago* (last edited 1 year ago)

This is a Bash fork bomb, a malicious function definition that recursively calls itself:

:() — defines a function named : (yes, just a colon).

{ :|:& } — the function's body:

    :|: — pipes the output of the function into another call of itself, creating two processes each time.

    & — runs the call in the background, meaning it doesn’t wait for completion.

; — ends the function definition.

: — finally, this invokes the function once, starting the bomb.
[-] Delta_V@lemmy.world 81 points 1 year ago

lol, as if Harvard were liberal

they're infamously, thuggishly conservative

[-] Delta_V@lemmy.world 106 points 2 years ago

Ukrainian farmer: "How do I put this hunk of junk into Neutral so I can load it onto my trailer?" *starts an argument on War Thunder forums*

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Delta_V

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