Not sure I follow your comment exactly, perhaps I am misunderstanding it but Hawking radiation doesn't involve anything escaping a black hole.
The radiation never originates from within the event horizon. Furthermore the radiation itself does not encode any information about what fell into the black hole apart from the electric charge, angular momentum, and mass (all of which must remain conserved).
It's been ages since I read it and I am 99% sure I'm remember horribly wrong, but I was thinking it's something like this? Also - your "the only information" is precisely what we can measure of quantum states, so information is still preserved. That's more a limit of what we know?
I think that with Hawking radiation you have quantum entanglement of two pairs. You have a matter-antimatter pair production near the horizon. When the antimatter falls into the blackhole without being destroyed via mutual annihilation, the matter particle at the boundary now "radiates" away. HOWEVER.
The matter inside boundary which the anti-matter DOES interact with is destroyed, and the information of that interaction is is "passed" to the outside via the the anti-matter's entanglement with its co-created pair.
Something like that, isn't it? Please any physicists clarify :)
> I think that with Hawking radiation you have quantum entanglement of two pairs. You have a matter-antimatter pair production near the horizon. When the antimatter falls into the blackhole without being destroyed via mutual annihilation, the matter particle at the boundary now "radiates" away. HOWEVER.
That's not how Hawking radiation actually works. It's just a "lies-to-the-children" explanation. Antiparticles have positive mass, so the black hole would be _growing_ as a result. This mechanism also violates the equivalency principle, as you shouldn't be able to detect the event horizon with only local observations.
Reality is more interesting. In flat space, the ground state of quantum fields is actually non-zero. But black holes "bias" the fields in such a way that their ground state becomes _negative_ from the viewpoint of a remote observer.
This in turn permits it to create new particles from just nothing. This in turn adds _negative_ energy to that space, resulting in the black hole decreasing in mass.
But crucially, the event horizon itself is NOT involved. Particle creation can happen anywhere in the vicinity of the black hole, not just on the event horizon.
The only caveat that I'd ask about is the death of a black hole after it evaporates away too much mass. If that explosion does occur, is that matter/energy that was from inside the singularity itself?
AFAICT nobody has a consistent theory proven by observations. Some theories offer an explosion in which the singularity vanishes, but this has trouble with information / entropy. Some say a microscopic remnant stops radiating because the original assumptions of Hawking radiation mechanism do not apply at near-Planck scale. Some say that as the curvature grows with the diameter shrinking, the black hole pops off from "our" spacetime and forms a parallel universe, without an explosion.
The current age of the Universe is way small compared to the time needed for evaporation, so observing anything like that happening (or not) is hardly possible.
Indeed All Hawking radiation takes from a black hole is some mass. It's a bit like radiation resulting from annihilation of matter and antimatter: it does not "escape", it "gets born" in the process.
I don't know the slightest about this but... That list looks like it is supposed to be limited but that sounds like infinitely more information than zero?
Hawkings radiation doesn't tell you anything about the contents of the black hole, just that it lost energy/mass. That reduces the event horizon, so there is now a (miniscule) amount of space that has become "visible". It'll be empty space, no extra mass is leaked in that way.
>> Not sure I follow your comment exactly, perhaps I am misunderstanding it but Hawking radiation doesn't involve anything escaping a black hole.
>> The radiation never originates from within the event horizon. Furthermore the radiation itself does not encode any information about what fell into the black hole apart from the electric charge, angular momentum, and mass (all of which must remain conserved).
> I don't know the slightest about this but... That list looks like it is supposed to be limited but that sounds like infinitely more information than zero?
I don't know about electric charge, but can't you observe mass and angular momentum of a black hole from outside? I think the "no information" thing means the Hawking radiation won't let you tell you if the black hole was made from a dead star or just a really big pile of meat or what's going on inside of it.
IIRC, all Hawking radiation does is provide a mechanism for a black hole to eventually decay.
We can play with words all day, but in the sense of a particle entering into the event horizon of a black hole and then at some point in the future exiting from inside of the event horizon, that simply never happens and Hawking radiation does not propose that.
People who actually did the original work care because this guy appears to be strip mining their content, running it through LLMs, and repackaging the result as if it were his own expertise. He also leans on inflated credentials to sell the illusion that he independently understands or developed the material. He's laundering other people's work through AI and personal branding, then taking the credit, so yeah that can piss people off and if you don't care then by all means continue supporting this hack.
It's not that physics feels no responsibility to explain why, it's that all other fields of science answer the why by punting to some lower level of science that is taken as an assumption until you get down to physics which has nothing lower level to punt to.
Psychology explains why you feel tired by pointing to biology. Biology explains why cells need ATP by pointing to chemistry. Chemistry explains why ATP releases energy by pointing to physics. Physics explains that by pointing to some higher level form of physics like thermodynamics, which points to statistical mechanics, which point to quantum laws. When you get down to a certain level you simply have nothing left to punt to. You simply accept it because it's what's observed and makes reproducible predictions or you don't and go study philosophy or religion or something.
Yeah you’re right. And also part of it is that I simply don’t know enough deep physics to maybe start to get a more “intuitive” grasp on things.
But on the other hand I do feel there are cases where other fields have true explanations without punting. It’s not all the time but sometimes. My favorite example is evolution. We observe evidence that species evolve over long periods. Why? Natural selection. It’s the entire explanation. And I suppose in some senses it punts on the mechanisms of natural selection - genes and molecular biology rest on physics and chemistry after all. But in terms of the why, why does evolution happen, I feel we have a complete answer that has that feeling of intellectual satisfaction and completeness that is, at least from my lay perspective, lacking in physics.
There is philosophy, but common physicists does not like going there, unless for rare cases like the author or Max Tegmark or Roger Penrose...
So they goes round and round, using more and more "dials" to stay within their framework, always kicking the can down the road a bit (its turtles all the way down), but never really answering the core questions...
> += deferred concatenation requires lazy strings and that didn't come until 10-15 years later.
CPython's += does not perform deferred concatenation and CPython does not use lazy strings. The optimization uses an eager in-place realloc if the string's ref-count is 1. This remains the optimization used even to this day and was introduced in 2005:
>However, concatenating string lists with sum() was a common Python idiom at the time
It could not possibly have been a common Python idiom since sum() explicitly rejected strings by throwing a TypeError. This was explicitly special cased to avoid the degenerate performance and the TypeError even has an error message saying "TypeError: sum() can't sum strings [use ''.join(seq) instead]".
>Gvr's reduce dislike was more about its syntax. It doesn't mesh well with Python's lambda syntax.
No it had nothing to do with mixing with lambda syntax, on the contrary GvR actually wanted to remove reduce and lambda (and map and filter as well). Here is the actual article by GvR regarding removing reduce, absolutely nothing in it involves how it mixes with lambda expressions.
>So now reduce(). This is actually the one I've always hated most, because, apart from a few examples involving + or *, almost every time I see a reduce() call with a non-trivial function argument, I need to grab pen and paper to diagram what's actually being fed into that function before I understand what the reduce() is supposed to do. So in my mind, the applicability of reduce() is pretty much limited to associative operators, and in all other cases it's better to write out the accumulation loop explicitly.
Yes thanks for finding the Python 2.4 release page which shows the optimization! So I remembered correctly -- Python already had that optimization back then. (There seems to be a large amount of confusion on that in this subthread)
And the March 2005 Artima post is also a very good reference! That actually predates my story, since Guido hadn't joined Google by then. I recall that he joined in December 2005.
So maybe the bug I remember was more of a "push" in the direction he had already thought of, not the direct inspiration.
It's clear from the blog post that he disliked all of map / filter / reduce, and then I'm sure that users or python-dev pushed back on removing them, so he settled for banishing reduce() to the stdlib.
The study addresses it. You don't walk into an ER and say "Doctor I have a gambling addiction.", rather you typically present as having a suicide attempt, intoxication or drug overdose, psychosis, or panic attack. During the assessment the treating team identifies the main contributing reason for one of the above listed conditions and there are two specific codes available if gambling is one of the primary contributors.
Where can I find an oven made with entirely US parts (or even ~85-90%+)?
I'll tell you in advance that I haven't been able to locate one in a few years of looking. Most major appliances are, at best, 60-80% american with no accurate accounting, even if they're "assembled in the USA". Cars are the only thing with accurate sourcing labels due to legislation.
Entirely US parts is a very high bar. Isn't it the final product design and assembly that counts in the end? If China has a comparative advantage making resistors, who cares, let them.
Not that you've explicitly claimed it's authentic, but the very idea of a pirate hunting tour is a hoax that resurfaces across the Internet every so often in different forms:
The radiation never originates from within the event horizon. Furthermore the radiation itself does not encode any information about what fell into the black hole apart from the electric charge, angular momentum, and mass (all of which must remain conserved).
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