archgoon

Why are you accusing the parent poster, who mostly agrees with you, of making an argument comparable to perpetuating slavery?

Sadly, but unsurprisingly, searching for "Crypto 2.0" does not yield information about a shift in cryptography. What time period was this around when this phrase was being used? Where could I find more info on it? What was the shift primarily about?

Chess has a well defined set of correct solutions. The rules are well known and understood.

Connections is much less so.

> Once you know speed of light is the maximum possible speed

But he didn't postulate this at all. He simply postulated (as per Newton) that light is made of particles with mass, which could thus be affected by gravity. Since they are moving at a finite speed, the light particles would be slowed down by gravity, and eventually completely stopped.

He further proposed, based on this model, that the mass of an object could potentially be determined by determining how much slower the particles were moving.

This doesn't work. Light doesn't really get slowed down by gravity, and you definitely don't have any slow light that was created from stars trillions of miles away.

It's a cool idea, but doesn't work with how light actually propagates.

The word 'system' is ambiguous and has multiple meanings. In general, and as per HN guidelines, you should assume good faith, and when someone guesses incorrectly about your assumed meaning clarify your definition.

That said, I'm shadow banned so you should probably ignore my advice on HN guidelines.

It iterates across sibling comment elements, hides them, until it encounters one whose indent level is less than or equal to the initial indent level.

> Woolf led himself astray with an entirely unsound theoretical model for the inner workings of his engine: he believed that steam at twenty pounds per square inch (psi) would expand to twenty times its volume before equaling the pressure of the atmosphere, steam at thirty psi would expand thirty times, and so on ad infinitum.

This seems to to exaggerate the incorrectness of Woolfs model. Assuming that the temperature is held constant (which apparently was stipulated in Woolf's patent) this is true according to the ideal gas law.

It is not clear where Woolf's model breaks down, but this part seems reasonable.

It is possible that the temperature was not held constant in his device, and, working off of the caloric theory of heat, assumed that the issue was leakage of either the original steam gas or of the caloric. In a sense, losing heat (caloric) would be to Woolf's model the same thing as having a leak.

I'm pretty sure they were just putting it in quotes because it was the expression you used, and they thus were referencing it.

But we aren't writing down people's IDs when they enter a bar/adult shops and sending it to a database that can later be queried by governments.

If you insist that `len` shouldn't be defined on strings, and the default iterator should be undefined in python then:

  for c in "Hello":
    pass

should throw an exception. Also

  if word[0] == 'H':
     pass

should throw an exception.

This would have been an extremely controversial suggestion when python3 came out to say the least.

Codepoints is a natural way of defining unicode strings in python, and it mostly works the way you expect once you give it a bit of thought. It is lower level than, say, grapheme clusters, but its more well defined and it provides the proper primitives for dealing with all use cases.

> If current quantum computers were scaled up to more qubits

That depends on what you mean by "scaled up". There is a concept of "Quantum Volume" that exists, which basically means the depth of the longest qubit circuit you can pull off.

https://en.wikipedia.org/wiki/Quantum_volume

'Simply' (it's never simple ;) ) adding qubits to a machine does not necessarily increase its Quantum Volume. Decreasing the noise typically will.

However, there is a threshold at which point you can scale up mostly indefinitely. This is what the whole Quantum Error Correction is all about.

https://en.wikipedia.org/wiki/Quantum_error_correction

There is a paper

https://arxiv.org/abs/1905.09749

That goes into a clear discussion of how to build a quantum computer and the associated thresholds that would allow you to do so. There is a minimum number of qubits needed (that work perfectly), but the paper analyzes how many qubits you'd need under realistic assumptions about how many noisy qubits you'd need to get error correcting qubits at the needed reliability.

I had never heard of this particular aspect of demanufacturing, that's fascinating. Do you know of any products where this was a deciding factor, or at least a major consideration? (I recognize you probably can't easily cite internal corporate documents)

This is a fiction. I'm not sure if it is pushed by corporate apologists, or by people trying to convince others the system is completely broken and must be destroyed (and replaced with system X).

An analysis of this claim:

https://www.nytimes.com/roomfordebate/2015/04/16/what-are-co...

In general, corporations are given a large leeway as to what is 'in the best interest of the coporation'. Fidiciuary duty basically means CEO's just can't run the company into the ground and spend all the cash on cocaine parties.

If we don't vary the sentence ("begins with, starts with, is prefixed with" etc...) and only consider the final part, then the number of english sentences is (unsurprisingly) equal to the number of possible hashes.

So for each distinct sentence, we pick randomly from the n different hashes, and we attempt to brute force this n times. So the probability of not getting this is:

(1-1/n)^n

As n increases, this will yield e^-1, so we have about a 36.7% chance of this not happening for any given length. So this has a probability of happening of 63.3%.

So there is a decent chance that there exists a sentence "The sha256 of this sentence is ..." for even the full sha256. If you are allowed to modify the sentence to be something like "'Begins with', 'starts with', 'OMG guys, check this out':" you can get this up to almost 1. Finding it would be mildly hard though barring some novel discovery about sha256.

Note, NASA has a copy of the original 2010 funding legislation here:

https://www.nasa.gov/pdf/649377main_PL_111-267.pdf

Which can also be found here:

https://www.congress.gov/bill/111th-congress/senate-bill/372...

The key part is:

> (2) MODIFICATION OF CURRENT CONTRACTS.—In order to limit NASA’s termination liability costs and support critical capabilities, the Administrator shall, to the extent practicable, extend or modify existing vehicle development and associated contracts necessary to meet the requirements in paragraph (1), including contracts for ground testing of solid rocket motors, if necessary, to ensure their availability for development of the Space Launch System.

Which explains why NASA isn't necessarily getting engines from Blue Origin or other cheaper new comers for example. The senate law dictates that they should continue using existing contracts. Now, could a NASA administrator argue that they should drop Aerojet (as cited in the ars technica article)? Potentially, but Aerojet could possibly sue, claiming that NASA is in violation of the law.

-- From the Shadows

> Honestly, that's like asking for a source for the fact that people need oxygen to live.

I find this attitude "It's just obvious" to be generally unhelpful. Your sibling comments do a much better job at helping the grandparent get up to speed with context about the SLS program, and associated Senate Legislation.

Being able to cite documents in support of your position is a valuable skill and both helps your own understanding, by clarifying what your understanding is based on, and that of the questioner.

-- From the shadows

This proposal is itself a nonsolution and distraction. You're not going to pull 7 billion people along with this.

We saw what a fairly massive reduction in consumption looked like during the pandemic. It basically put CO2 levels back to what they were in 2016. That's no where nearly enough.

Right; but the point is that the optimizations didn't require an entirely new language; you just take the core logic and write it in an existing language that has decades of optimizations. If you're doing math; there's likely a natural, well defined interface that can be used, so you just call that interface from Python, which has historically always been the point of 'glue' languages :)

Spiffy! Do you remember what were you using as your model?

(Btw, 'moot' not 'mute' :) )

The ctf community is fairly active.

Http://ctftime.org

Yes, the Rutherford gold foil experiment was basically where we went from "It's a positive sphere with some electrons stuck in it" to "Oh, looks like there's a super dense positive center and the rest is mostly empty space".

The author of the article is welcome to compute the mass density of the atom's periphery to the nucleus, and return to speculating whether it's fair to argue that the atom is mostly empty space or not.

For myself, I'm happy to refer to ethereal probabalistic cobwebs as "mostly" empty space.

So there are 5 observed bosons, and one postulated graviton.

The strong force is associaed with the gluon.

The Electromagnetism gets the photon.

The Weak force gets the Z and W+/- bosons.

Gravity gets the graviton, but that's mostly a placeholder since we don't know how to properly model gravitational effects with QFT.

Higgs doesn't get associated with a force (yet).

> Even this sample could be marginal, going by the original paper.

If the sample they claim is superconducting isn't superconducting; why should we assume that this material is a superconductor at all? Because of some vague idea that their prof thought it might be more than 2 decades ago?

It is not a trivial extension. If you need all infinite number of derivatives to predict motion than your theory is non predictive.

He works for Setec Astronomy.

It's not glomming on when these things are basically the core aspects of reality.

You haven't really come to grips with what a world that was mostly inconsistent would look like.

> What determines the amount of information?

Noise. Your ability to distinguish between states.

> If you have a carbon atom, does it have unlimited information because it theoretically could instead have been some other number of atom

You don't even need that. A single hydrogen atom has an infinite number of bounded energy states. In principle, you could store infinite information by putting an electron in the nth energy state and keeping it there.

In practice, you can't, due to noise.

This is not the first university where grad students have unionized. Most of the UC's have been unionized for decades.

It is not that strict. Many years ago machine code was directly loaded into memory and wherever the cpus program counter was, that's what it'd execute.

These days, a page of memory can be set to

Read Write Execute

The exploit mitigation you refer to is having the program typically set pages of memory to never have both write and execute set at the same time.

However, this is ultimately controlled by the program. On Linux, the program can invoke the os call 'mprotect' to change the permissions on a page (though a program can also voluntarily use seccmp routines to forego ever invoking this ever again)

And this is basically what browsers do. They compile the code into memory that has been set to 'write' (but not execute) and proceed to then set it to execute (but not write).

The effectiveness of this mitigation is mitigated by the existence of ROP techniques, which is why Intel started introducing Control-flow Enhancemnent Technology (CET), which is intended to ensure you can only branch to certain locations in memory.

The US government did not murder Aaron Schwartz. The story is tragic enough without misrepresenting his mistreatment by the government.