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stoperaticless commented on Antimatter production, storage, control, annihilation applications in propulsion   sciencedirect.com/science... · Posted by u/belter
codethief · 9 months ago
One obstacle is momentum conservation: You can't just turn a single massless particle (a photon, say) into a massive one or vice versa because that would violate conservation of 4-momentum. The way out is to involve more than one massless particle in that interaction, e.g. convert two massless particles into one or more massive ones, or vice versa. (If a single massive particle is produced, the 3-momentum of the two massless particles cancels out in the center-of-mass frame, while their energy / p_0 adds up to the rest mass of the particle that's produced.)

Which interactions exactly are possible depends on the particles & forces involved, and further conservation laws for quantum numbers (e.g. charge) that the force obeys.

TL;DR Turning a single massless particle into a single massive one is not possible, you always need at least two.

stoperaticless · 9 months ago
Could two particles be: anti proton and anti electron?

(What conservation law would it violate?)

stoperaticless commented on The Depths of Wikipedians   asteriskmag.com/issues/08... · Posted by u/Brajeshwar
cxr · 9 months ago
> Wiki, open source projects, stackoverflow and democratic country, all are different, but they definitely have similarities.

A unicycle and a hula hoop have similarities.

As I said, the distinction matters. The argument by metaphor in your previous comment is off-base.

Feel free to address concretely what I wrote in my previous comment.

(Though I have doubts about the quality of any insights that might be offered; no one referring to Wikipedia as "Wiki" is informed enough about Wikipedia to be informative about it.)

stoperaticless · 9 months ago
I think you want me to address the policy, that you linked to.

Well, the wiki’s policy is irrelevant. Or only 50% relevant.

I see that the policy tries to provide some “spirit of the law” and/or hints to avoid edit wars and such, but evidently many follow the policy only in letter and just know what not to mention, i.e. to not trigger the policy. (instead of rejecting edits with “I own this” or “I know this better”, edits get rejected with “citation needed”)

> As I said, the distinction matters.

I see you sincerely believe that it does, but I’m of different opinion.

People in any group form a hierarchy, and have (frequently unwritten) “traditions”. And those are features, not bugs.

Hierarchy is not necessarily strict or formal, but it helps with coordination.

“Tradition” is the actual way how things are done. “Tradition” can be changed by policies, it may even implement the policy to the letter, but it always encompasses more than the policy contains. Because it’s almost impossible and most undesirable to have policies for each breath we take.

> Feel free to address concretely what I wrote in my previous comment.

Somebody has older account then me here and is feeling authoritative I see. Thanks for good practical illustration.

stoperaticless commented on The Depths of Wikipedians   asteriskmag.com/issues/08... · Posted by u/Brajeshwar
cxr · 9 months ago
Editing Wikipedia is not the same as developing software, and they're different enough for the distinction to matter. Wikipedia is not Nupedia, and the comparison in this comment between Wikipedia and open source software maintenance is simply flawed from the start.

Wikipedia explicitly does not have owners.

<https://en.wikipedia.org/wiki/Wikipedia:Ownership_of_content>

The statement that "one must earn the right to discuss" alone has the minor problem that it is totally antithetical to the actual policies and guidelines that Wikipedia aims to adhere to.

stoperaticless · 9 months ago
Wiki, open source projects, stackoverflow and democratic country, all are different, but they definitely have similarities.

Established old-timers have significantly more authority than newbies in any organisation.

Trust built over time matters.

stoperaticless commented on The Depths of Wikipedians   asteriskmag.com/issues/08... · Posted by u/Brajeshwar
Timwi · 9 months ago
> established editors should try to do a better job helping people learn the ropes

Translation: you're not welcome unless you adhere precisely to established editors’ views and practices. There is no room for introspection, civilized discussion that questions the status quo, and hence, no room for improvement.

stoperaticless · 9 months ago
Maintainer stance is understandable. They are the ones taking on the risks and who will be left dealing with consequences.

Flyby contributors don’t know how much effort there is to keep things going even at good enough level. It’s up to the newcomer to convince that the new opinion matters and new risk is worth taking.

Maintainers can’t distinguish between troll and flyby-contributor-never-to-be-seen-again and genius-that-will-sacrifice-everything-for-the project.

I get that you can’t convince of anything if they don’t discuss, but that means one must earn the right to discuss, by becoming part of current organisation.

Illustrative analogy from open source project (not mine).

Project had top level directories like “ext” and “external” and “vendor” (which is confusing at the first glance). Potential contributor made PR to rectify it (memory slips on how; but seemed reasonable at first glance). Owner/Maintainer rejected this help. The would be contributor got frustrated, later complained here that the project did not care about code quality and best practices and is hostile to new contributors. I see Chesterton’s fence here and a bit of entitlement on the would-be-contributor’s side.

stoperaticless commented on Boltzmann brain   en.wikipedia.org/wiki/Bol... · Posted by u/josephwegner
quantadev · 9 months ago
It's about quantum mechanics and the fact that "empty space" is not really empty. Particles do pop into existence (from nothing), according to QM, so there's a non-zero probability for any "pattern" to pop into existence. Sort of like if you have an infinite number of coin flips then at some place and time you'll land on heads a million times in a row, no matter how unlikely. And for any million-bit sequence you're guaranteed to hit it too. So a human "brain" is just a pattern that's likewise guaranteed to be "encountered".

A similar concept is how the first replicator RNA/DNA got created as the beginning of life. If RNA can exist in large numbers of random sequences, then a sequence that can replicate itself only has to "happen" once and then life is started and will never slow down but will grow in complexity, as long as the environment can support it.

stoperaticless · 9 months ago
> Sort of like if you have an infinite number of coin flips then at some place and time you'll land on heads a million times in a row, no matter how unlikely.

If random event result is any real (i.e. not limited integers and fractions) number from interval 0-1, then no number will appear twice even after infinite number of throws.

Open question surely follows: Time and space, are they integer or real?

stoperaticless commented on JSON parsers that can accept comments   douglascrockfordisnotyour... · Posted by u/todsacerdoti
MathMonkeyMan · 9 months ago
It's true that Douglas Crockford is not my dad. My dad is a different person entirely.

It's a bad idea to write JSON parsers that can accept comments. Comments are not part of JSON.

There are plenty of extensions to JSON, and they have parsers. Use them. Or, use a language that is already an extension to JSON, like JavaScript or YAML.

stoperaticless · 9 months ago
I want to highlight, that extra bad part is keeping the name “json parser”.

(Naming it my-custom-format parser would circumvent ambiguity)

stoperaticless commented on JSON parsers that can accept comments   douglascrockfordisnotyour... · Posted by u/todsacerdoti
avodonosov · 9 months ago
If and when commas improve readability for you, feel free to use them in EDN.
stoperaticless · 9 months ago
That possible when you control the creation process. Frequently you can’t control the creation (e.g.external system)
stoperaticless commented on South Korean president declares martial law, parliament votes to lift it   apnews.com/article/south-... · Posted by u/Inocez
cameldrv · 9 months ago
Perhaps that could have been true for the shipments of shells, but I can't see NK sending tens of thousands of troops to a meatgrinder that they have absolutely no stake in just for some fertilizer and oil. NK has the ability to demand much more strategic things and I'd be virtually certain that they have.
stoperaticless · 9 months ago
Also, “well being of people” < “military stuff”
stoperaticless commented on Python type hints may not be not for me in practice   utcc.utoronto.ca/~cks/spa... · Posted by u/ingve
scoofy · 9 months ago
My objection to strong types in python is philosophical. Python mimics natural language, and natural language rejects strong types for context resolved ambiguity.

In the way we resolve these issues in natural language, we can resolve bugs in python, that is, “do you mean integer ’3’ or string’3’” instead of insisting we define everything always forever.

To me, people who use type hinting are just letting me know they have written code that doesn’t check in line.

stoperaticless · 9 months ago
Strong/weak types and static/dynamic typing are orthogonal things.

Strong type system limits things like 1+”1”.

Static type system requires type declarations (“int i”).

Python always had strong dynamic types.

stoperaticless commented on Hey, wait – is employee performance Gaussian distributed?   timdellinger.substack.com... · Posted by u/timdellinger
diggan · 9 months ago
> the first is they assume employees are (or should be) paid according to how much they earned the company

From the perspective of a employee and/or human, that does seem like the most fair way of distributing what the company earns, sans the money that gets reinvested straight back into the business itself. But I'd guess that'd be more of a co-operative, and less like the typical for-profit company most companies are today.

stoperaticless · 9 months ago
There is no way to unambiguosly decide who is responsible for which earnings.

Hipothetical two people cooperative that produces simple hammers. One specializes on wooden part, the other on metal part. How much each of them earned to the company? (Or producing and selling; or one spending his lifesavings to buy pricey hammer-making-equipment while other presses buttons on said equipment)

u/stoperaticless

KarmaCake day290April 14, 2024View Original