The news you hear about helium supply is not (or shouldn't be) about extractable amounts on the planet — it's about what's commercially available.

Extraordinary amounts of helium are just discarded during things like natural gas extraction because helium isn't profitable enough for those companies to extract, store, and sell. That means commercial supply goes down and, with constant or increasing demand, price goes up. At some point, it becomes profitable to separate and sell it again, at which point supply increases, price goes down, and the cycle repeats.

This process is being intensified, especially in creating lower price floors, by long-standing selloffs of nationalized helium reserves that were created when we thought dirigibles were the future of warfare.

https://medium.com/a-microbiome-scientist-at-large/science-monday-are-we-really-running-out-of-helium-c5365852cbd3

Helium is effectively a non-renewable resource (decay products are created very slowly and need to accumulate over millions of years to be harvestable, besides) and we will run out of it someday, but that day is still very far off and unlikely to happen in the lifetime of anyone alive barring major life extension advancements (yes, please!).

What we will see is continued boom/bust cycles as reserves are depleted and markets stabilize on current real extraction costs. And it'll likely be a steady increase over time as the long-term depressive effect of stockpile release dwindles.

Helium can be synthesized via nuclear reactions and, in a hypothetical situation where the Earth really "ran out," that's what we'd likely end up doing. It'd just be many orders of magnitude more expensive than today and probably make asteroid capture look very appealing. But that hypothetical day is very far off past much more prominent existential threats.

I'm not impressed by my toaster's computational capacity, either.

ChatGPT isn't meant to replace search by itself. https://help.openai.com/en/articles/6783457-chatgpt-general-faq

> ChatGPT is not connected to the internet, and it can occasionally produce incorrect answers. It has limited knowledge of world and events after 2021 and may also occasionally produce harmful instructions or biased content.

Using a magic language model like this together with a search index, though, has a lot of potential. Which is not so coincidentally exactly what the Bing thing is working towards.

You know how salt has historically been used as a de-icer? That's because salt water has a lower freezing point than normal water, meaning it has to get colder to freeze.

When it gets cold enough anyway, salt water forms something with the cool name of a "eutectic frigorific mixture," which establishes crystals of high-heat-transfer ice crystals on skin at much, much lower temperatures than normal ice. That means really bad frostburn with no sensitivity to know you're even being burned.

This has apparently been idiotically embraced as an "internet challenge" enough to merit a Wikipedia page: https://en.m.wikipedia.org/wiki/Salt_and_ice_challenge

>The mixture of ice and salt create eutectic frigorific mixture which can get as cold as −18 °C (0 °F).[3]

>The salt and ice challenge can quickly cause second- and third-degree injuries similar to frostbite or being burnt with the metal end of a lighter, as well as causing painful open sores to form on the skin. Due to the numbing sensation of the cold and possible nerve damage during the stunt, participants are often unaware of the extent of any injuries sustained during the challenge, only feeling pain once the salt on their skin enters lesions created during the challenge. Skin discoloration from the challenge may remain after the challenge has been attempted.[4][5][6]

Or perhaps people with such behavioral patterns idly check their phones more.

Causation is an enormous and unwarranted leap. The correlation is interesting and valuable, but that's still all it is.

Sometimes. "Aging" is a remarkably complex set of processes and still in its very early stages of being properly understood. Some causes of aging, when treated and addressed, really do "reverse" apparent age — in reality, this is addressing flaws in replication process and moving that function back towards normal, but from the outside it does appear that the new tissue is functionally "younger" than the old.

One special case (telomerase deficiency) induced and exercised in mice: https://www.nih.gov/news-events/nih-research-matters/aspects-aging-might-be-reversed

Everything in your body (almost) is continuously replacing itself at various speeds. If there's a problem that's causing replicated cells to behave as if they're more degraded ("older") than they otherwise would be, then treating that and having the next replacement round be more functional than its precessor is effectively "reducing age" as an apparent and functional measure.

If the source cells have accumulated replication errors or otherwise been intrinsically "damaged," however, you need much more intensive and hitherto "exotic" treatments to make all the trillions of pieces of "future human" to look and act younger than "current human," and "slowing aging" is a lot more readily attainable in those circumstances.

Potatoes are a lot better food than they get credit for, but in a world where the majority of people are overweight we need to look at micronutrient density relative to calories before food weight.

A modest bunch of spinach packs almost 2g of potassium for under 100 calories. That sounds like a lot of spinach until you cook it--it shrinks a ton. You'd need like 500 calories worth of potatoes (or 700+ calories from a nice bunch of those overrated bananas) to match.

In general, all those leafy green and cruciferous vegetables that people hate are very favorable in micronutrient density to macronutrient content, potassium included.

Meat, beans, and potatoes are all "decent" potassium sources, but particularly in the context of sodium/potassium balance (which seems to have at least as much bearing as raw intakes do) and how hard it is to keep sodium intake down, it's hard to get enough potassium without at least a little bit of veggie love.

Sir, would you like that steak medium, well-done, or plasma?

A potential crude analogy to this with a healing process that's much more visible to us is with sunburns.

While your skin is actively damaged by overexposure, you may or may not experience a certain set of symptoms with flushing, itching, irritation and sensitivity. For a long time afterwards, even with no active damage continuing to happen, you then deal with itchiness, sensitivity, flaking, peeling, and all the other delights of dermal repair.

Respiratory infections damage respiratory tissue in a parallel way to the sunburn. Once infection has been fought off, a lot of inflamed, compromised structure needs to be repaired and replaced and we respond to inflammation and debris by coughing.

>Hydrogen has one fourth the energy density of jet fuel

Just to call out: as density decreases, fuel requirement goes up a lot worse than linearly. You have to burn fuel at the beginning of the flight to transport the fuel you'll use for the rest of the flight, and the more fuel you need, the more dire that picture looks.

The exact numbers would depend on a lot of variables (weight and distance chief among them) but most flights, even the smaller and shorter ones that are feasible with hydrogen's energy density, will need way more than four times the fossil fuel amount in hydrogen.

I do think that hydrogen (and even BEV in narrow situations) might have a place in limited aviation scenarios (very short/light flights) but completely agreed that the math just doesn't work for either of these electric modalities to replace fossil fuels in-place for long, heavy flights — and that's not a "point in time, technology will keep getting better" thing.

Asymptomatic infections can create damage and it's a very real problem.

For example, it's a concern that there are observed, enduring differences/abnormalities in the lungs of even asymptomatic COVID-19 convalescents that could greatly complicate future treatments, e.g. here in radiation therapy for certain cancers:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7462877/

Along with more publicized "long COVID" sequelae, these kinds of things are why the myopic focus on fatality rates throughout the pandemic has been so stupid; for every already-at-risk person killed by a primary infection, there are hundreds, thousands, or even more who are going to experience some degree of complexity in the onset, management, and treatment of future problems, many of those patients having noted little or no acute symptomology during primary infection.

We spend way, way more on healthcare than defense. If you diverted every penny from defense into healthcare, you'd see one of three outcomes:

1. The optimistic one: modest but meaningful improvements take hold in healthcare outcomes; nothing revolutionary, but good enough evidence that dumping more money into healthcare without systemic changes can still improve things.
2. The pessimistic one: corruption and inefficiency in distributing new influxes of funding into healthcare results in a situation where everything is even more corrupt and less efficient, and the extra money results (at least indirectly) in worsened outcomes and accessibility while accelerating the deterioration as those windfall profits are internalized.
3. The mixed one: some small gains are offset by some small screw ups and the net impact of the monetary infusion is ambiguous, with some dimensions of healthcare getting some measurable improvements and others actually getting worse.

In all three cases, the consequences would likely be irrelevant fairly quickly because the geopolitical vacuum left by the US military vanishing would destabilize global economies (even more) and likely spark wars we no longer had any defense against.

Reducing the US role as world police and improving US healthcare need to be tackled as separate problems with different timelines.

• For defense, we need phased handoff of accountabilities to trusted allies who step up to the plate; Russia is a really clear reminder of why the lifetimes of comparative peace (and outsourced violence) that most readers from Western countries enjoy is not a given — and with continuing pressure building from developing world population growth and climate change, the backdrop of instability isn't realistically going to improve all that much over time. If the US is going to pull back its defense spending, it needs to do it slowly and methodically. In reality, it may be better to just spend it more intelligently, which is something that e.g. semi-autonomous warfare initiatives like the drones discussed in this article could actually do.

• For healthcare, we really need to fix the money-leaking system before we just dump more money into it. We already pay way, way more than anyone else in the world for "good but not always the best, highly inaccessible care" and we should expect vastly diminishing returns if we just throw extra funding at it. It's a lot more complicated than just wholesale switching to a single-payer system, but most of the "exponential profit machines" do need to be removed from the equation; without checks, free market is going to naturally converge towards highest cost for least-quality acceptable product, and even if that anti-capitalist sentiment is exaggerated and oversimplified there's still clearly some hard truth to it in what we see happening.

If we find a way to cross the streams and divert some incrementally and intelligently pulled back military spending into a reformed healthcare system that actually makes good use of that money? Then fantastic. But this is far, far more layered than "military bad, healthcare good, give military money to healthcare, good!" ... Which is unfortunately a prevailing sentiment.

It's a continuum with bigger, denser, and otherwise harder to consistently rewarm and perfuse ramping the difficulty up, likely on a non-linear scale.

We may well see cryonically frozen lab rats fully resuscitated in the coming years (likely still with lots of complications at first), but we should contain our optimism given there's probably at least at much of a gap between cycling an embryo or tardigrade and cycling a rat as there will be between cycling a rat and cycling a human. We have notoriously hungry brains!

Speed and perfusion. Big problems both during freezing and thawing:

For freezing, water is the enemy. It expands and forms crystals as it freezes, which together rupture cell membranes and effectively ravage tissues. If you just drop someone into a cryonic vat as-is, the brick of icy cellular mush you get will be far too damaged to ever be viable again. If you're familiar with freezer-burned meat, imagine that happening to everything in your body, including your heart and brain. Not pretty.

The workaround for that is antifreeze. Yes, seriously. Get all the water out of a person that you can and replace it with something that won't crystallize and thaws early enough to allow replacement during resuscitation. But that's where speed and perfusion are nightmares: every minute you're waiting to freeze someone while you replace water is a minute that tissues are dying from anoxia. This is the worst with the brain: it dies really, really fast without oxygen and yet the blood-brain barrier makes it one of the hardest places to achieve non-water perfusion with.

That said, there have been advancements with this where cooling the body to just about freezing to slow neuronal cellular death combined with better antifreezes and techniques might get us close to reaching "frozen" with something that's still viable. A rabbit brain was successfully frozen and thawed using some of these -- though, notably, not yet in a rabbit: https://www.newscientist.com/article/2077140-mammal-brain-frozen-and-thawed-out-perfectly-for-first-time/

So we might be kinda-sorta close to getting cryonically frozen humans that are damaged lightly enough bring back. Very doubtful anyone frozen today is, but we might be there within a few decades.

Thawing is even harder, though. Even in the best-case scenario, you have a bunch of critically oxygen-starved tissue frozen; every second of anoxia counts once things unfreeze, and the brain in particular really needs to go from frozen to "warm and oxygen-perfused" very, very quickly. Human brains are really dense and, as mentioned, really hard to permeate -- we don't currently have much of any clue about how we'd warm a brain out of cryonic suspension enough to restore blood and oxygen without having orders of magnitude more anoxic duration than those brains can take. Exotic ideas abound about blood replacements that can achieve oxygen transport while still perfusing a very cold brain, but it's all total conjecture at this point.

And that aside, the dance when you restart everything else in the body is hard, too. You need to swap all of the liquid in the entirety of very complex human vasculature -- including at least most of what exists intercellular media and the like -- and restore circulation with oxygen very, very quickly and very, very consistently. Simplifying a bit, but if you hand reaches 1C while your arm is still -2C, you're going to have a bunch of things in your hand die while your arm is waiting.

We don't have any real line of sight on how to achieve this super-fast, super-consistent, super-precise reoxygenation of a big, complex organism with all of the systemic coordination that's necessary. There's nothing to say it shouldn't be achievable someday, but let's just say we have no reason to believe it'll come sooner than commercial fusion.

But why are embryos OK? Because they're small and easy to perfuse! You can get all of the damaging water out of embryonic structures and flash freeze it way before the lighter anoxic time constraints kick in, and it's not (comparatively) hard to warm and reoxygenate them quickly and consistently enough to have them in a good, healthy state years and years later. Smaller organisms -- especially ones that evolved resilient structures -- can already be revived that way, too: tardigrades and other similar animals have been thawed after tens of thousands of years: https://www.smithsonianmag.com/smart-news/scientists-revive-tiny-animals-spent-24000-years-ice-180977928/