It's hard to know how to take this given that their first example (function call overhead) seems deeply flawed -- you'd never have a 'compare' strings function take std::string by value. (Maybe const string& or string_view). Also, the alternative would have to have a destructor of some type (unless it is a string_view analog) to make it an apples to apples comparison.
the entire article rests on a shorter String that can be fit on registers reliably. If you have bytes in registers, it is not clear that passing bytes by value is "deeply flawed."
You'd never have a `compare(std::string a, std::string b)` function in your code base. It would make copies of the strings (and destroy them). So it seems to me the article is comparing their new thing to a straw man.
Does being the destroyer in the dark forest scenario not reveal yourself to other destroyers?
Also while I'm sure a relativistic kill vehicle could neutralize a planet, will it also get all the populated moons/orbitals in the system? What if the target species is already multi-system?
Accelerating a rock to intercept a separate star system doesn’t need to generate any particularly noticeable emissions.
If it was intercepted someone could work backward from its trajectory and determine an origin, but the odds of noticing a cold, small, dark rock at relativistic speeds early enough to do anything about it seems slim.
It is a nice scheme, but what if your target is not bound to gravity wells anymore and the most of its economy is artificial structures orbiting its sun?
You will hit some ancient rocks orbiting the star, and even if people there dont need them anymore they are bound to become curious of the origin of your missiles.
Sending a relativistic chunk of tungsten is something we could accomplish at essentially current technology levels. Hell we could send a hundred of them. It’d be expensive and it would take awhile to get there but we could do it in a decade given sufficient motivation.
If caveman-level weaponry is sufficient to take out anyone not well on their way to becoming a Type II civilization, I’m betting on the cavemen.
I don't think we could do this at all, even theoretically.
If we took all the proven petroleum reserves in the world, and magically converted them into kinetic energy with 100% efficiency— With zero overhead for transportation, launch, agriculture, or obeying conservation of momentum— That still wouldn't be enough to launch even a single planet killer. At most you could crater a small country, but not kill a civilization:
So let's say you do nuclear pulse propulsion like Project Orion. You've still got Tsiolkovsky's rocket equation to deal with. Assuming a speculative fusion bomb ISP of 75,000s, you would need a rocket with… over 50 orders of magnitude more mass than the entire observable universe, in order to accelerate a single proton to 0.9c:
Light sails will be huge, obvious/visible, and slow. Beamed power will run into issues with diffraction.
In fact, reaching 0.9c while you're still in the solar system plainly implies maintaining multiple hundreds of g's of acceleration over many dozen astronomical units of distance. That doesn't seem feasible at all. It's wildly beyond not only our best existing ion drives, but probably also any remotely feasible existing concept for space propulsion.
This probably isn't true: we don't even have enough conventional weapons to destroy our own planet, and we've been optimizing that for centuries. A relativistic missile is a conventional weapon scaled up.
We couldn't accomplish this. Theoretically speaking, yes we could, but "theoretocally" means "ignoring the half of the reality". We can't even travel to Moon now practically.
To send a chunk of tungsten at a relativistic velocity would mean an effort for trillions of dollars. Don't forget that it is not enough to just get a chunk of tungsten moving, you want it to hit a moving target, and you'd better add some thrusters to it and a guidance system. Is there anyone willing to pay for that?
Any civilization will need to concentrate a lot of efforts to fire a chunk of tungsten, but why might it do it? There are better ways to utilize that effort. Maybe it is a rational thing to go aggressive nevertheless, but the benefits will be in a far future while politicians needs to justify spending now. People and societies are not rational. There is no real examples of rational agents, but people still insist on treating rational agents as something real. Theoretically speaking AGI might become a rational agent, but I doubt it from a practical standpoint: AGI will be limited by a computational power and by its abilities to gather data. So it will use heuristics, and it will be not rational. It can be closer to a platonic ideal of a rational agent then human, but even that is not free of doubt. People surpisingly well do with all their heuristics and when they appear irrational it is mostly due to inability of observers to understand the real motivation of people.
You need a much more advanced civilization to be as aggressive. A civilization that can do it by spending maybe 0.1% GDP for 10 years. At least looking at humanity, I'd say that any cost higher than that will not work definitely.
Such unprovoked and costly agression having no observable results easily could end a lot of political careers.
Theoretically speaking we can ignore all these difficulties and start with the assumption that it is possible to concentrate 100% GDP on a one task for years or even decades. Practically it is impossible.
Maybe another civilization will have another structure and will be able to concentrate efforts on a larger scale then humanity? Maybe. But could you imagine such a hypothetical civilization and estimate chances of it to get to a sufficiently advanced level? I cant neither. So while I keep in mind this theoretical dreams of rational civilization purging each other, I do not assign any credibility to them. I keep myself in an uncertain state, the best state to have an open mind, to be ready to absorb any evidence or reasoning.
They might notice the bits of interstellar dust that at the upper size range hit at 0.99c with kinetic energy on the order of magnitude of tactical nuclear weapons yield. This also makes targeting interesting without thrusters and fuel to correct their probably regularly perturbed trajectories. Those cold, small, dark rocks may not be quite so cold or dark if they're going to actually try to hit their targets.
It might be better to say raw_ptr<T> is a dumb pointer wrapper. raw_ptr is discouraged in favor of unique_ptr/WeakPtr/RefCounted; but it is used in places where you'd have a T* at rest.
IMO the friendly fire on his camp was a cover/false flag to begin the "march for justice". The coordination/speed his coup attempt had couldn't be set up in such a short amount of time (since the "friendly fire" incident), so it was planned for at least a few weeks.
I don't think this logic applies to the demographics of today. The total number of humans to have ever lived is calculated to be ~105 billion. So assuming you're applying that logic to today, you're one of the most recent ~7%, which doesn't seem that remarkable -- at least not to the point of assuming fatalistic scenarios.
If humanity continues like this with no new discoveries then in ten million years we would have 200 million per year * 10 million years = 2 quadrillion people. Getting a human who lived at the start of that peak is very improbable.
But you are right, civilization lasting another few thousand years isn't that improbable. Just that it is strange that it would last a thousand years but not a million, seems like humanity should have figured out how to stabilize things if civlization lasts that long.
Edit: Or maybe our ultimate downfall will just be lack of evolutionary pressure so at some point nobody can sustain civlization. That wouldn't happen in a thousand years but a million years is definitely enough.
Edit2: Or we solve our lifespan issue very soon and people no longer die, so people also no longer can procreate or they would exhaust available resources.
I'm pretty sure the issue with Spectre/Meltdown is about an OS process reading other processes' (or kernel) memory. These are fundamentally chip issues, not developer issues.
No, Spectre is always about reading your own memory. Your link is about exploiting MDS aka Zombieload — a separate hyper-threading vulnerability, specific to Intel CPUs.
The issue with Meltdown is about an OS process reading other processes' (or kernel) memory - this is caused by the CPU not enforcing its protection boundaries properly and is mitigated by CPU microcode or firmware updates.
The issue with Spectre is about an OS process (or kernel) reading its own memory - this is why in contrast to Meltdown it can't be fully fixed by CPU microcode or firmware updates, it requires mitigation in any code that enforces security boundaries, such as kernels or sandboxing VMs.
it's not that the algorithm "breaks"; it's just that it stops being a convenient notation for humans.
the "short" notation relies on the ability to squeeze the remainder in between the digits of the dividend. if you have a divisor greater than ten, it's possible to have a remainder with more than one digit. two or more remainder digits is a lot harder to write legibly between the digits of the dividend. you also end up subtracting larger numbers in your head, which is error prone. finally, most people only memorize the multiplication table up to 12x12 or so. once they can't simply do a lookup into their memorized table, they switch to more of a "guess and check" approach, where they will inevitably have to cross out or erase their previous work.
in the end, it introduces a lot of unnecessary opportunities to make mistakes and hides stuff that people can't do reliably in their heads.
A web search says your approach (which I admit I don't follow) is off by a factor of 40 -- the Sun moves approximately 500k mph around the galactic center. A speed 8x slower than the star mentioned in the article.
The GP is talking about the sun’s apparent speed in Earth’s sky, which is dominated by Earth’s rotation. Another way of stating it:
The sun is 1 AU distant and appears to revolve around Earth once a day from our perspective so it has apparent speed of 6.28 AU / day or 2.4 million mph.
Their point is that unless this star was very close to us it wouldn’t appear to move quickly across the sky, because the sun has similar apparent velocity and looks stationary to our eyes.
"Quick" being relative to your expectations, of course.
If OP is right, and it moves six times faster than the sun, then it would go from one side of the sky to the other in just three nights, right? That's extremely fast for any star gazer. Faster than any planet we can see. Someone who was familiar with the night sky and who could see this star would notice its speed quickly.
If UBI is just printed, then sure there would be economic problems; but I think the idea is you redistribute it via taxation.