ED: "But it doesn't work for gravity with linear curvature"

Relativity = gravity is represented by the curvature of spacetime. Curvature is linear, R. The formula treats curvature linearly. As things get closer and curvature spikes, the math just scales at a 1:1 rate

Quadratic gravity = Squares the curvature. Doesn't really change things much when everything is far apart, but heavily changes things when everything is close together.

Pros: prevents infinities and other problems when trying to reconcile quantum theory with relativity ("makes the theory renormalizable"). E.g. you don't want to calculate "if I add up the probabilities of all of these possible routes to some specific event, what are the odds that it happens?" -> "Infinity percent odds". That's... a problem. Renormalization is a trick for electromagnetism that prevents this by letting the infinities cancel out. But it doesn't work with linear curvature - gravitons carry energy, which creates gravity, which carries more energy... it explodes, and renormalization attempts just create new infinities. But it does work with quadratic curvature - it weakens high-energy interactions and allows for convergence.

Cons: Creates "ghosts" (particles with negative energies or negative probabilities, which create their own problems). There's various proposed solutions, but none that's really a "eureka!" moment. Generally along the lines of "they exist but are purely virtual and don't interact", "they exist but they're so massive that they decay before they can interact with the universe", "they don't exist, we're just using the math out of bounds and need a different representation of the same", "If we don't stop at R^2 but also add in R^3, R^4, ... on to infinity, then they go away". Etc.

The theory isn't new, BTW. The idea is from 1918 (just a few years after Einstein's theory of General Relativity was published), and the work that led to the "Pros" above is from 1977.

In short, Java was invented for a reason, and while it has become a victim of legacy cruft as well, the underlying concept of truly portable apps, with a minimum of fuss to jump from platform to platform, still ought to be the preferable path. The problem is that that true platform neutrality/ambiguity pretty much kills Microsoft in all but a few niches, like gaming, but only because hardware vendors put less effort into drivers for other operating systems.

Yes, Office is still king, although I think that crown is beginning to slip, and it may end up being Excel, with its large list of features, that may last the longest. But it isn't 1990, or even 2000 anymore. Developers have multiple ways of developing portable applications, and while MS may (for the nth time) update or swap out its toolchains, the real question is will developers really care?

A bit more about the latter. Beyond organophosphates, the main other alternative is pyrethroids. These are highly toxic to aquatic life, and they're contact poisons to pollinators just landing on the surface (some anti-insect clothing is soaked in pyrethrin for its effect). Also, neonicotinoids are often applied as seed coatings (which are taken up and spread through the plant), which primarily just affect the plant itself. Alternatives are commonly foliar sprays. This means drift to non-target impacts as well, such as in your shelterbelts, private gardens, neighbors' homes, etc. You also have to use far higher total pesticide quantities with foliar sprays instead of systematics, which not only drift, but also wash off, etc. Neonicotinoids can impact floral visitors, with adverse sublethal impacts but e.g. large pyrethroid sprayings can cause massive immediate fatal knockdown events of whole populations of pollinators.

Regrettable substitution is a real thing. We need to factor it in better. And that applies to nanoplastics as well.

So, when we say microplastics, we really mainly mean nanoplastics - the stuff made from, say, drinking hot liquids from low-melting-point plastic containers. And yeah, they very much look like a problem. The strongest evidence is for cardiovascular disease. The 2024 NEJM study for example found that for patients with above-threshold levels of nanoplastics in cartoid artery plaque were 4,5x more likely to suffer from a heart attack. Neurologically, they cross the brain-blood barrier (and quite quickly). A 2023 study found that they cause alpha-synuclein to misfold and clump together, a halmark of Parkinsons and various kinds of dementia. broadly, they're associated with oxidative stress, neuroinflammation, protein aggregation, and neurotransmitter alterations. Oxidative stress is due to cells struggling to break down nanoplastics in them. They're also associated with immunotoxicity, inflammatory bowel disease, and reproductive dysfunction, including elevating inflammatory markers, impairing sperm quality, and modulating the tumor microenvironment. With respect to reproduction, they're also associated with epigenetic dysregulation, which can lead to heritable changes.

And here's one of the things that get me - and let me briefly switch to a different topic before looping back. All over, there's a rush to ban polycarbonate due to concerns over a degradation product (bisphenol-A), because it's (very weakly) estrogenic. But typical effective estrogenic activity from typical levels of bisphenol-A are orders of magnitude lower than that of phytoestrogens in food and supplements; bisphenol-A is just too rare to exert much impact. Phytoestrogens have way better PR than bisphenol-A, and people spend money buying products specifically to consume more of them. Some arguments against bisphenol-A focus on what type of estrogenic activity it can promote (more proliferative activity), but that falls apart given that different phytoestrogens span the whole gamut of types of activation. Earlier research arguing for an association with estrogen-linked cancer seems to have fallen apart in more recent studies. It does seem associated with PCOS, but it's hard to describe it as a causal association, because PCOS is associated with all sorts of things, including diet (which could change the exposure rate vs. non-PCOS populations) and significant hormonal changes (which could change the clearance rate of bisphenol-A vs. non-PCOS populations). In short, bisphenol-A from polycarbonate is not without concern, but the concern level seems like it should be much lower than with nanoplastics.

Why bring this up? Because polycarbonate is a low-nanoplastic-emitting material. It is a quite resilient, heat tolerant plastic, and thus - being much further from its glass transition temperature - is not particularly prone to shedding nanoplastics. By contrast, its replacements - polyethylene, polypropylene, polyethylene terephthate, etc - are highly associated with nanoplastic release, particularly with hot liquids. So by banning polycarbonate, we increase our exposure to nanoplastics, which are much better associated with actual harms. And unlike bisphenol-A, which is rapidly eliminated from the body, nanoplastics persist. You can't get rid of them. If some big harm is discovered with bisphenol-A that suddenly makes the risk picture seem much bigger than with nanoplastics, we can then just stop using it, and any further harm is gone. But we can't do that with nanoplastics.

People seriously need to think more about substitution risks when banning products. The EU in particular is bad about not considering it. Like, banning neonicotinoids and causing their replacement by organophosphates, etc isn't exactly some giant win. Whether it's a benefit to pollinators at all is very much up in the air, while it's almost certain that the substitution is more harmful for mammals such as ourselves (neonicotinoids have very low mammalian toxicity, unlike e.g. organophosphates, which are closely related to nerve agents).

While it is an enormous problem, possibly the most significant, we know how to shield against radiation, but it's going to take mass in the form of hydrogen-rich molecules like water or polyethylene (as examples). To solve that problem we are either going to have to make launches a lot cheaper, or figure out how to do it all in orbit.

It's at the edge of our technological capacity to produce such a spacecraft now, so the barrier is economic. That's a massive barrier, but in theory we definitely could, if we put a significant percentage of GDP of the wealthiest nations towards the project, produce a spacecraft that keep astronauts alive and relatively protected from ionizing radiation both on the journey and while on Mars.

As to your general assholery, I guess everyone has to have an outlet, though why Slashdot is a bit mysterious.

The Second Amendment was intended to be a check on federal power. None of the amendments were incorporated into jurisprudence about what individual states could do until arguably 1890 and not certainly until the early 1920s. Many states had laws around firearm storage for decades. In the 1830s, Massachusetts was the first among several states to generally bar carriage of firearms in public. Texas would follow suit in 1871.

The Heller decision written by Scalia was a sea change in constitutional law, but it laid down important limits that were respected in the MacDonald decision that followed soon after and which incorporated the Second Amendment as applying to states as well as the federal government. Scalia wrote that firearm law limitations were presumptively lawful, and essentially laid down an opportunity for the federal government to prohibit future types of weapons sales by preventing them from becoming publicly available. Here's what he wrote (citations removed).

We also recognize another important limitation on the right to keep and carry arms. Miller said, as we have explained, that the sorts of weapons protected were those "in common use at the time." We think that limitation is fairly supported by the historical tradition of prohibiting the carrying of "dangerous and unusual weapons."

It may be objected that if weapons that are most useful in military service—M-16 rifles and the like—may be banned, then the Second Amendment right is completely detached from the prefatory clause. But as we have said, the conception of the militia at the time of the Second Amendment’s ratification was the body of all citizens capable of military service, who would bring the sorts of lawful weapons that they possessed at home to militia duty. It may well be true today that a militia, to be as effective as militias in the 18th century, would require sophisticated arms that are highly unusual in society at large. Indeed, it may be true that no amount of small arms could be useful against modern-day bombers and tanks. But the fact that modern developments have limited the degree of fit between the prefatory clause and the protected right cannot change our interpretation of the right.

Scalia had no problem with regulating or even banning public availability of broad classes of weapons as long as those available to the public continued to be available to the public. In his view, existing weapons like missiles and new weapons like portable lasers could be banned because they were not "in common use." However, Scalia died in 2016, and the Court has moved to a substantially broader view than he had.

What are you going to do when Nazi Trump really ramps up the persecution? Oh right, sit back and protest and hope the government doesn't murder you all, ie just like Iran did to it's protesters two months ago.

The people who have clamored most over the last 40 years about government overreach are largely those most supportive of Trump's tyrannical behavior. However, the fastest growing segment of gun owners in the last couple of years are those on the left, with even more disproportionate growth among minorities. There are a lot of former military who are very unhappy with the direction that he's taken, too. There are a lot of guns on both sides and not nearly enough police or military to handle them all.

So far, the Trump administration's own overreach has been embarrassing enough to force them to back off. The videos of the deaths of Renee Good and Alex Pretti were bad enough, but the responses by almost everyone up to and including Trump in labeling them terrorists and declaring that the ICE and CBP agents did no wrong before we even had multiple views of what happened caused them to backpedal (even the NRA chimed in against the administration). Bovino was removed from Minnesota and demoted, resulting in him either deciding or being forced to retire. They sent Tom Homan in, and the first thing he did was withdraw half of the agents assigned there, and most of the rest have returned to their assigned jurisdictions. Noem's constant bluster and media presence have sidelined her in the administration, destroyed almost any chance of a political future and cast a permanent pall over the brutal enforcement actions under her watch. Her replacement, Markwayne Mullin, isn't much better in terms of policy goals, but he has said that he doesn't like and doesn't want the constant press from extreme actions. The GOP, including Trump, is being forced to negotiate on things in the DHS budget bill that Trump declared just a couple of weeks ago were nonnegotiable. Trump's actions in Iran have backfired, and so far, the only negotiations happening seem to be in his own imagination, leaving him looking even worse, even among his own supporters.

They're weak and they know it, and their support isn't as solid as it was a year ago. Whether this means they continue to back down or they suddenly lash out, I don't know. But if they do move to mass violence, it isn't going to be against a group of unarmed pansies entirely incapable of shooting back. I hope it doesn't come to that, because it will become impossible to predict the outcome.

Trump has issued 101 pardons in his first 13 months of office, many of whom were very obviously guilty of serious crimes and for which Trump was expecting a quid pro quo. The Cuellars are a prime example. The evidence against them was overwhelming, yet Trump pardoned them and then got angry that he registered to run as a Democrat for office in his district. And there's Changpeng Zhao, whom Trump didn't know anything about but pardoned on the idea that his prosecution was a "Biden witch hunt." We're supposed to ignore that Peng's company made the Trump family $2 billion richer a few months before.

Mikrotik has manufacturing in Europe and China, as well as Vietnam and Malaysia. Their higher-end stuff seems to be made in Europe, but that doesn't necessarily mean that parts of those aren't made in China.

I hate all of this sales pressure BS - that the instant anyone hears your name you have to try to "convert" them to sales - and I literally run a webstore.

It's all so deeply anti-consumer, and I want no part in it.

I'm not fond of Musk, but this part about SpaceX is just blatantly untrue. Falcon 9 has an enviable record, with only two full failures and one partial failure out of 619 launches. Of the 602 attempted recoveries, they've made 589 of them using 53 boosters for an average of 11 launches per booster, with at least one (B1067) completing 33 landings.

NASA has most certainly not given up on reusable rockets. They continue to plan for the Falcon line to be used, and New Glenn has some contracts with more likely coming as it demonstrates reliability. Vulcan is supposed to eventually get reuse capability (we'll see), and NASA uses that, too. Even most of the smaller rockets have or are developing reuse capability.

Tesla is a mess, Musk had to get SpaceX to buy Twitter and Grok, and Starship is clearly having more problems than expected, but SpaceX's core Falcon operations are working just fine.

For power, he will likely divert a bunch of solar panels and grid-scale batteries from Tesla.

The bigger issue is that he wants to put this close to sources of vibration, like the Tesla gigafactory that uses high impact tools to shape metal. Apparently reputable commenters elsewhere have said that these impacts, while invisible to human sensations, are likely enough to affect high-sensitivity chip manufacturing operations. Existing fabs all over the world have to take into account traffic from nearby highways, and the gigafactory will be even closer and involve sharper impacts.

He has also dismissed concerns about clean rooms in the past, saying that they're overblown, and that he'll be able to eat a cheeseburger and smoke a cigar in the same rooms that are running manufacturing operations.

He was good as an idea man for a while, but his ideas have lost contact with reality.

ASML uses the calendar year for its fiscal year, so it's the same thing.

This debate has been going on for at least a couple of decades. I remember back in the Usenet days, when AOL and other early ISP users first started showing up in droves with whacked out untraceable bang paths that people were trying to sort out technical solutions, usually involving some servers tarpitting some domains, with the inevitable consequence that valid users (by whatever definition any given Usenet group had) were blocked.

In a way, AI bots aren't any different than the spam problem on fax machines and email; universal low-barrier delivery meets large scale programmatic swill. AI allows complexity that earlier spambots couldn't dream of, when the most sophisticated way of defeating filters was spelling "porn" as "pr0n" and a bit of header fuckery. In the end there is only two ways to go; either do what filtering you can and accept some degree of false positives, or go to identification systems that will, one way or the other, compromise anonymity, because make no mistake, once you start storing any kind of data linking an account to an actual human being; biometric, picture ID, phone number, mailing address or whatever, it won't take long for the court order to show up demanding you hand over all the de-anonymized account data to find the person distributing child porn, drugs, or calling their local political representative dirty names.

Firstly, I see you have this notion that martian rocks must all be igneous.

You're not talking about rock, you're talking about regolith.

Depending on where the regolith is sourced

Regolith is not "sourced", it's blown across the whole planet. It's not simply "whatever the underlying strata is made out of".

But, since we are playing 'name the ignorance' in this exchange, your attestation stat perchlorate is 0.5% liberatable oxygen says 'Say i'm ignorant of basic chemistry without saying i'm ignorant of basic chemistry, and am bad at reading too.' The 0.5% statistic comes from the publication at bottom, and is the proportion of the regolith that is perchlorates.

I am the one who mentioned that regolith is 0.5% perchlorates, not that "perchlorates are 0.5% oxygen". *facepalm*

"Saying we'll get oxygen from the 0,5-1% of a poison in martian regolith, rather than bulk ice or CO2, is..."

For God's sake, learn to fucking read.

Washing the regolith to remove the perchlorate is a requirement for *any* other use of that regolith

Which is why you shouldn't be celebrating its existence. It is a problematic contaminant, not a resource.

As you have rightly pointed out, the water ice on mars is more 'frozen mud'. Cleaning the melt is going to be a necessary first step to using it *regardless*. That means either vacuum distillation, thermal distillation, or reverse osmosis filtration. Again, NOT OPTIONAL. This is necessary equipment that you need to bring, regardless.

And this just to get water, the most basic of offworld resources. And all of that equipment (especially the mining hardware itself) requires maintenance and spare parts, which impose more dependencies. And the TRL for use on Mars is low regardless.

You've gone from talking up the ease of operating on Mars to talking it down, yet your self-righteousness hasn't shifted at all in the process.

RO filtration is the least energy intensive of these.

Except, it isn't. 0,5-1% perchlorates. RO typically removes 90-95% of perchlorates. So you're down to ~500ppm. Human safety levels** are in the low parts per billion. You're five orders of magnitude off. Yes, you can purify water that far - and the more perchlorates, the easier - but you're talking an over millionfold reduction. It is not at all trivial. You're talking first RO to get it down to levels where it won't hinder bacterial growth, then bioreactor bacterial remediation, then filtration, then RO, then ion exchange. This is not some little, simple system.

** Plants can tolerate much more perchlorates than humans, but they also bioaccumulate perchlorates of exposed to them, so you have to reduce the water to low ppb levels.

The end products are clean water and perchlorate contaminated mud, and clean mud, with contaminated water.

Viola! *eyeroll*

And your "plan" for dealing with waste perchlorate doesn't just magically produce pure O2 and NaCl in the real world. First off, molten sodium perchlorate, which is what it becomes before it decomposes, is an extremely corrosive oxidizer. Exactly what are you planning to make the furnace out of, platinum? Secondly, you never get perfect decomposition. Apart from residual perchlorates, you have residual sodium chlorate, which is also corrosive, and is a literal herbicide. And your gas stream will contain contaminant chloride and chlorine dioxide, which, news flash, you don't want to breathe.

There is no way on Earth anyone would ever prefer this to just conducting electrolysis on the water that you've already purified.