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Is it correct that there is a difference between an umbrella and a unique solution, despite the vowel?
Umbrella and unique solutions ?fresh_42 said:Is it correct that there is a difference between an umbrella and a unique solution, despite the vowel?
Any Tim's son, however, should probably keep his head down.WWGD said:If auto ( in)correct is at the cutting edge of A.I, there should be no fear of machines rebelling and taking over any time soon.
Astronuc said:It appears from the last paragraph that there was evidence of 'the crack' from May 2019. It's not clear to me at present, if they are saying the crack was partial or fully through the beam. If it was clear that there was a crack, then there was a complete failure in the inspection process that allowed continued operation of the bridge in that condition.
MEMPHIS, Tenn. (AP) — Photos taken by a Mississippi River kayaker about five years before a crack was found in the Interstate 40 bridge linking Tennessee and Arkansas appear to show the fracture that led transportation officials to close the span indefinitely last week.
Arkansas transportation officials said they cannot confirm or refute what’s shown in the 2016 photos, which raise questions about how early the crack appeared.
I have and I have. Thanks.WWGD said:I suggest if you have a clear, specific idea of your research topic you can start looking for someone to work with
WWGD said:Confusing-enough, Python's Linear Algebra contains...Modules.
lambda f: c/f
By the way modules. I tried to figure out the English term for the sum of simple submodules, which in German is Sockel. It turned out to be socle. Now is this a loanword and who borrowed from whom, or is it a parallel development from some medieval word?WWGD said:Confusing-enough, Python's Linear Algebra contains...Modules.
Lambada? You're out of Sync, Ibix.Ibix said:It's the lambda lambda.Python:lambda f: c/f
Ask Ibix, it seems to see with the Lambada Calculus.fresh_42 said:By the way modules. I tried to figure out the English term for the sum of simple submodules, which in German is Sockel. It turned out to be socle. Now is this a loanword and who borrowed from whom, or is it a parallel development from some medieval word?
Socle? Never heard of it.fresh_42 said:By the way modules. I tried to figure out the English term for the sum of simple submodules, which in German is Sockel. It turned out to be socle. Now is this a loanword and who borrowed from whom, or is it a parallel development from some medieval word?
I hadn't either, but Wikipedia has: Socle (mathematics)WWGD said:Socle? Never heard of it.
The German word is very common, in its meaning of the pedestal where statues are placed upon, not the submodule.WWGD said:Socle? Never heard of it.
I'd call that a plinth, if I didn't call it the thingy a statue stands on. I'd never heard socle as far as I'm aware. The English etymology is here, from Latin indirectly. I suspect German got it the same way.fresh_42 said:The German word is very common, in its meaning of the pedestal where statues are placed upon, not the submodule.
This sounds as if a German mathematician named the submodule Sockel and the English word socle was taken from that rather than the other way around.Ibix said:I'd call that a plinth, if I didn't call it the thingy a statue stands on. I'd never heard socle as far as I'm aware. The English etymology is here, from Latin indirectly. I suspect German got it the same way.
That's a skirting board in English.fresh_42 said:this is a 'Sockelleiste',
The other two descriptions are more telling:Ibix said:That's a skirting board in English.
I don't really understand what a mathematical socle does - could it be seen as a supporting entity for a larger or more general construction? If so, someone probably borrowed the architectural term
In the U.S. the term I am most familiar with would be "baseboard".Ibix said:That's a skirting board in English.
wiki said:(also called skirting board, skirting, wainscoting, mopboard, floor molding, or base molding)
Guns almost give the same result, so I don't think we need that.etotheipi said:I wonder if there will ever be commercially available tiny black hole pellets that you could just throw at people and it sucks them up. Some things to consider would be manufacturing the black hole pellets in situ, keeping them stable before ejection and the mechanism of the absorption on impact. Also I don't know how the resulting body would interact with the Earth. But anyway I think black holes can eventually be weaponised.
"Black holes have no hair". They radiate gravitational waves and very rapidly sink into a state completely characterised by mass, angular momentum, and charge. So you can have weird shapes (e.g. during a merger - you can find LIGO-authored animations online) but only transiently.etotheipi said:Actually, does anyone know if there are more exotic shapes that black holes can take other than just the boring spherically symmetric one?
Black holes have no hair.etotheipi said:Wonder if anyone knows how to find the vibrational modes of a black hole
Ignoring the question of how one would go about "throwing" such a thing, there's a bigger problem that any black hole with the mass of mere pellet would almost instantly, after the moment of creation, explode rather cataclysmically due to Hawking radiation. It wouldn't be sucking anything in; rather it would be blowing things apart.etotheipi said:I wonder if there will ever be commercially available tiny black hole pellets that you could just throw at people and it sucks them up. Some things to consider would be manufacturing the black hole pellets in situ, keeping them stable before ejection and the mechanism of the absorption on impact. Also I don't know how the resulting body would interact with the Earth. But anyway I think black holes can eventually be weaponised.
I did not study at all this phenomenon of Hawking radiation yet, because first it is necessary to study the Bogoliubov transformations. So I take your word for this. But why will this process be violent, I was under the impression Hawking radiation was a slow process?collinsmark said:Ignoring the question of how one would go about "throwing" such a thing, there's a bigger problem that any black hole with the mass of mere pellet would almost instantly, after the moment of creation, explode rather cataclysmicly due to Hawking radiation. It wouldn't be sucking anything it; rather it would be blowing things apart.
I believe it is the Sponge Bogoliubuv transformation.etotheipi said:I did not study at all this phenomenon of Hawking radiation yet, because first it is necessary to study the Bogoliubov transformations. So I take your word for this. But why will this process be violent, I was under the impression Hawking radiation was a slow process?
It's very, very slow for stellar mass black holes or larger. But for hypothetical black holes with masses on the order of a human (tens or even hundreds of kilograms) it's very fast -- more akin to a thermonuclear weapon's energy discharge type of fast.etotheipi said:I did not study at all this phenomenon of Hawking radiation yet, because first it is necessary to study the Bogoliubov transformations. So I take your word for this. But why will this process be violent, I was under the impression Hawking radiation was a slow process?
Well they don't have actual hair either. But there are "no hair" theorems showing that black holes have no identifying characteristics beyond mass, angular momentum and charge. They radiate everything else away in extremely short time. Ask Peter for details...etotheipi said:What does it mean "no hair"? I guess you don't mean actual hair, because I'm pretty sure there's no keratin in a black hole...
I don't know much either, but I do know that the temperature of the radiation scales inversely with mass, so small black holes radiate more, becoming smaller so radiating yet more. Positive feedback.etotheipi said:But why will this process be violent, I was under the impression Hawking radiation was a slow process?
Ah okay, yes I see in the textbook the relation ##\tau \sim M^3##collinsmark said:It's very, very slow for stellar mass black holes or larger. But for hypothetical black holes with masses on the order of a human (tens or even hundreds of kilograms) it's very fast -- more akin to a thermonuclear weapon's energy discharge type of fast.
In fact, their Hawking temperature is below the CMB temperature, so even an isolated black hole will net absorb energy and increase in mass and will continue to do so for a long time until the CMB has cooled.collinsmark said:It's very, very slow for stellar mass black holes or larger.
Probably. You're reaching the point where I know facts but don't know the reasoning. Talk to Peter...etotheipi said:These are all Komar integrals yes? So the no hair theorem is to say this is a maximal set of independent Komar integrals that fully characterise the black hole, is that correct?
I don't know the origin of the expression, but that's what they're called.etotheipi said:But I do not see the connection to hair