Tag: nuclear
What makes a nuclear winter so extreme and destructive?
This may be a sort of, pertinent to the times, and disturbing question, inspired by the difficulties surrounding North Korea and the situation with it and nuclear weapons.
I’ve heard of this idea of “nuclear winter” that can result from a nuclear exchange, and more interestingly, very surprisingly, and disturbingly, that a major winter could be caused by even a “small” nuclear exchange, like on this paper:
http://climate.envsci.rutgers.edu/pdf/WiresClimateChangeNW.pdf
suggests that only “150 teragrams” of “smoke” released from a Nuclear exchange, would be able to produce a HUGE temperature drop of 7 degrees C for a couple of years or so, with attendant devastating effects on agriculture – indeed there’s another version of this I saw with a map showing far greater temperature drops, like 20 degrees C or more, in places like Europe and North America (the USA) over land, right where the breadbaskets would be. Considering that it’s not just crops but other plants as well that would be affected, its would seem to be a geologically significant event for a fair number of life forms, not just humans.
But the thing I’m having trouble with is just how is this possible, in particular, this magnitude, because it seems to be comparable to, if not greater than, natural events that would seemingly be of far greater magnitude. The 150 teragrams of carbon soot is only like a cube 400 meters on a side when solid, which is then vaporized and spread throughout the atmosphere, but that seems utterly tiny compared to the release of thousands of cubic kilometers of ash and other materials from volcanic and supervolcanic eruptions(*), much more asteroid strikes like Chicxulub releasing doubtless millions of cubic kilometers of material of all sorts. Is the soot really tens or hundreds of thousands of times more powerful per unit mass at cooling than anything released from any of these events would be? Or what? Further, especially considering that an event like Chicxulub would no doubt have ignited at least continentscale areas of of forests in the area around it if nowhere else from the ejecta storm, which doubtless would have produced far more black carbon soot than burning down all the cities in a nuclear war, no? Yet this suggests effects that, while not equal, seem almost comparable – and this is considered for a much diminished set of arsenals, compared to what they were at their peak, suggesting the peak could perhaps even eclipse the Chicxulub at a tiny fraction of the total energy release from the latter. What would have happened to the Earth in an imaginary scenario where the 100 million megatons (400 zettajoules) of Chicxulub asteroid energy were replaced with 100 million megatons of hydrogen bomb mushroom clouds exploding over a comparable area of forests (alien attack? 🙂 ) to those that the asteroid would have burned, 6566 million years ago?
(*) See, e.g.
https://en.wikipedia.org/wiki/Toba_catastrophe_theory
https://en.wikipedia.org/wiki/Toba_catastrophe_theory#Volcanic_winter_and_cooling
where it is mentioned how that the Toba super volcanic eruption was first thought to have produced a big cooling, but more recent evidence suggests it may not have. Yet the nuclear war seems able to almost match it, with only 150 teragrams of carbon vs. 6 000 teragrams of SO2. Now of course maybe the former is better absorber (gas vs. fine dark solid), but literally so much better that the latter could barely move the meter (according to observational evidence, not the simulation mentioned), while the former would drop it 7 degrees C, 20+ in some areas? And that’s just the SO2 component, what about all the other material released by the eruption to no doubt similar very great heights? And furthermore, how does this all fit in with Chicxulub? Is there any data on the “anti greenhouse” power of C soot versus SO2 and other materials released by volcanoes and asteroid strikes?
In short, what makes nuclear weapons so damn good at being destructive, compared to everything that nature seems to have in its arsenal short of the death of the Sun itself, despite seemingly the much greater raw power in terms of energy of the latter?
Convex mixed linear integer programming with real nuclear norm objective and linear integer objective
Khachiyan and Porkolab in ‘Integer optimization on convex semialgebraic sets’ gave an $O(ld^{ O(k^4)})$ algorithm to minimize a degree $d$ form with integer coefficients of binary length at most $l$ over integer points in a convex set in $Bbb R^k$. Is similar parametrization possible with nuclear norm?
This is my reasoning nuclear norm is convex and algebraic and therefore there has to be a semialgebraic convex representation. Then by Heinz https://core.ac.uk/download/pdf/81196255.pdf it should be fixed parameter polynomial time.
The precise problem is as follows:

We have $n$ integer variables

We have $r$ real variables

We have $m$ constraints

We have a linear or semi algebraic convex objective function that depends only on integer variables

We have a nuclear norm minimization objective function that depends only on real variables
Is it possible to find a feasible solution in $O(n^{poly(n)}poly(rm))$ time?
Translation of “A car powered by nuclear fuel.”: zero article or partitive article
(J’ai rencontrÃ© le terme “zÃ©ro article” dans le livre: A student grammar of French by M. Offord, p. 204.)
Comment peuton traduire la phrase ciaprÃ¨s ?
A Car Powered by Nuclear Fuel.
Une voiture alimentÃ©e par combustible nuclÃ©aire
ou
Une voiture alimentÃ©e par du combustible nuclÃ©aire.
How to determine isospin $T$ (not just $T_z$) of a nuclear ground state
Iâm trying to work out the total isospin and the $z$component of the isospin for specific elements like $^{20}O$ and $^{20}F$ in the ground state. Iâve worked out the $z$component, as I concluded this is just
$$T_z=(1/2) (ZN).$$
My question is how do I work out the total isospin? I had a look at the nndc and found the isospin of $^{20}O$ to be $T=2$, but how do i calculate this?
I tried adding the 8 proton (isospin 1/2) and the 12 neutron (isospin 1/2) but itâs wrong and I am unsure of how the total isospin itself is calculated.
Question: How long would it take for america to recover if the major USA Cities were hit with Nuclear…
Convex integer programming with nuclear norm
Khachiyan and Porkolab in ‘Integer optimization on convex semialgebraic sets’ gave an $O(ld^{ O(k^4)})$ algorithm to minimize a degree $d$ form with integer coefficients of binary length at most $l$ over integer points in a convex set in $Bbb R^k$. Is similar parametrization possible with nuclear norm?
This is my reasoning nuclear norm is convex and algebraic and therefore there has to be a semialgebraic convex representation. Then by Heinz https://core.ac.uk/download/pdf/81196255.pdf it should be fixed parameter polynomial time.
What makes a nuclear winter so extreme and destructive?
This may be a sort of, pertinent to the times, and disturbing question, inspired by the difficulties surrounding North Korea and the situation with it and nuclear weapons.
I’ve heard of this idea of “nuclear winter” that can result from a nuclear exchange, and more interestingly, very surprisingly, and disturbingly, that a major winter could be caused by even a “small” nuclear exchange, like on this paper:
http://climate.envsci.rutgers.edu/pdf/WiresClimateChangeNW.pdf
suggests that only “150 teragrams” of “smoke” released from a Nuclear exchange, would be able to produce a HUGE temperature drop of 7 degrees C for a couple of years or so, with attendant devastating effects on agriculture – indeed there’s another version of this I saw with a map showing far greater temperature drops, like 20 degrees C or more, in places like Europe and North America (the USA) over land, right where the breadbaskets would be. Considering that it’s not just crops but other plants as well that would be affected, its would seem to be a geologically significant event for a fair number of life forms, not just humans.
But the thing I’m having trouble with is just how is this possible, in particular, this magnitude, because it seems to be comparable to, if not greater than, natural events that would seemingly be of far greater magnitude. The 150 teragrams of carbon soot is only like a cube 400 meters on a side when solid, which is then vaporized and spread throughout the atmosphere, but that seems utterly tiny compared to the release of thousands of cubic kilometers of ash and other materials from volcanic and supervolcanic eruptions(*), much more asteroid strikes like Chicxulub releasing doubtless millions of cubic kilometers of material of all sorts. Is the soot really tens or hundreds of thousands of times more powerful per unit mass at cooling than anything released from any of these events would be? Or what? Further, especially considering that an event like Chicxulub would no doubt have ignited at least continentscale areas of of forests in the area around it if nowhere else from the ejecta storm, which doubtless would have produced far more black carbon soot than burning down all the cities in a nuclear war, no? Yet this suggests effects that, while not equal, seem almost comparable – and this is considered for a much diminished set of arsenals, compared to what they were at their peak, suggesting the peak could perhaps even eclipse the Chicxulub at a tiny fraction of the total energy release from the latter. What would have happened to the Earth in an imaginary scenario where the 100 million megatons (400 zettajoules) of Chicxulub asteroid energy were replaced with 100 million megatons of hydrogen bomb mushroom clouds exploding over a comparable area of forests (alien attack? 🙂 ) to those that the asteroid would have burned, 6566 million years ago?
(*) See, e.g.
https://en.wikipedia.org/wiki/Toba_catastrophe_theory
https://en.wikipedia.org/wiki/Toba_catastrophe_theory#Volcanic_winter_and_cooling
where it is mentioned how that the Toba super volcanic eruption was first thought to have produced a big cooling, but more recent evidence suggests it may not have. Yet the nuclear war seems able to almost match it, with only 150 teragrams of carbon vs. 6 000 teragrams of SO2. Now of course maybe the former is better absorber (gas vs. fine dark solid), but literally so much better that the latter could barely move the meter (according to observational evidence, not the simulation mentioned), while the former would drop it 7 degrees C, 20+ in some areas? And that’s just the SO2 component, what about all the other material released by the eruption to no doubt similar very great heights? And furthermore, how does this all fit in with Chicxulub? Is there any data on the “anti greenhouse” power of C soot versus SO2 and other materials released by volcanoes and asteroid strikes?
In short, what makes nuclear weapons so damn good at being destructive, compared to everything that nature seems to have in its arsenal short of the death of the Sun itself, despite seemingly the much greater raw power in terms of energy of the latter?
Feasibility of running a fast food restaurant after a nuclear war?
So, nukes are falling outta the sky, and the apocalypse is here. After, slavery makes a comeback, mutants are created, and raiders plague the land.
Youâre a manager, who operates a well known Waffle Serving outlet. The CEO of the company has demanded that, nukes or otherwise, you will continue serving food indefinitely. Would it somehow be feasible to keep doing so, if your Waffle Residenceâs employs were committed enough to try?
This is a joke, donât take it too seriously. Just curious
Is there a “nuclear option” regarding the election of a constitutional judge in Germany?
In Germany, the parliament has just agreed on a successor for one of the judges of the constitutional court. The candidate has to be elected in parliament with 2/3 of the votes as well as the majority of all members.
As smaller parties can therefore have a blocking minority, this lead to informal agreements of the parliament fractions who alternatingly support the candidate of the others (it’s a bit more complicated as this, see BPB – “HandwÃ¶rterbuch des politischen Systems der Bundesrepublik Deutschland” / Bundesverfassungsgericht, Section 4, Par. 4, and also sometimes disregarded (Legal Tribune Online, 12.02.2008).
However, as far as I could find in the laws (see below), this required 2/3 of the votes is not mandated by the constitution, but in the “Law about the federal constitutional court” (BVerfGG). Laws can be changed with simple majority in parliament.
 Could a simple majority in parliament and state chamber (Bundesrat) therefore replace this requirement and elect a candidate by altering the BVerfGG as a “nuclear option” similar to the US?
 If the parliament cannot agree within 2 months, the court itself proposes three candidates (BVerfGG Â§7a (1)). What happens if the parliament cannot agree with 2/3 of the votes on one of them?
Laws I could find:
Art. 94(1) GG (Constitution)
(1) Das Bundesverfassungsgericht besteht aus Bundesrichtern und anderen Mitgliedern. Die Mitglieder des Bundesverfassungsgerichtes werden je zur HÃ¤lfte vom Bundestage und vom Bundesrate gewÃ¤hlt. Sie dÃ¼rfen weder dem Bundestage, dem Bundesrate, der Bundesregierung noch entsprechenden Organen eines Landes angehÃ¶ren.
BVerfGG Â§6 (1) (normal law)
(1) Die vom Bundestag zu berufenden Richter werden auf Vorschlag des Wahlausschusses nach Absatz 2 ohne Aussprache mit verdeckten Stimmzetteln gewÃ¤hlt. Zum Richter ist gewÃ¤hlt, wer eine Mehrheit von zwei Dritteln der abgegebenen Stimmen, mindestens die Mehrheit der Stimmen der Mitglieder des Bundestages auf sich vereinigt.
BVerfGG Â§7a (1)
Kommt innerhalb von zwei Monaten nach dem Ablauf der Amtszeit oder dem vorzeitigen Ausscheiden eines Richters die Wahl eines Nachfolgers auf Grund der Vorschriften des Â§ 6 nicht zustande, so hat das Ã¤lteste Mitglied des Wahlausschusses unverzÃ¼glich das Bundesverfassungsgericht aufzufordern, VorschlÃ¤ge fÃ¼r die Wahl zu machen.