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Ever been in a 747 and have a ships' radar pick you out?

I've just discovered the paper Measuring Propagation Speed of Coulomb Fields (PDF) which appears to show that the Coulomb field (& also gravitational fields) travel with infinite speed. The authors also dismiss a critique of their research here (PDF). The theory is way over my head, so I am wondering what the views are of the better educated on S.F as to the merit of the authors' conclusions.

@Moontanman I could watch that aquarium all night.

They said that about calling ll Mexicans rapists, and the Access Hollywood tape, and about saying John McCain wasn't a war hero b/c he got captured, and about calling predominantly black locations shithole countries, and for disowning our allies, and for having secret service rent golf carts from his properties every time he travels, and for golfing more than the last several presidents combined for hundreds of millions of dollars in tax payer money, and for tweeting classified satellite images of Iran, and for telling his team to fire Mueller, and for not releasing his tax returns, and for saying he had no reason to believe our intelligence community or disbelieve Putin, or for raising our cost of goods through tariffs with China, or for asking again for foreign aid in our elections, or for having the military book and pay for vacant rooms at his properties even though they weren't staying there, or for having the VP fly across Ireland to stay at his properties when his meetings were 3 hours away, or for robbing his charity for kids with cancer, or for calling senators unamerican for being black or muslim, or for saying there are very fine people of both sides of a white supremacist rally, or.... or again... and or some more...

In my view it's about having a certain understanding of pain that different animals experience, and taking steps to mitigate or protect them against inhumane treatment. It's about having a higher respect for different forms of life, even so called "lower" forms of life such as plants, which we now know behave in remarkable and seemingly intelligent ways. Demise is one thing - everything dies - but imprisoning an animal from birth until death while subjecting it to inhumane treatment is different. That's where a code of ethics needs to play a role.

Hello, Imagine, the SETI-Project has reached contact to something about 5 light years in distance and we switch some of the first years, so the communication with the aliens is in English. One of the researchers (“SEARCH”) is logician and mathematician, as those fields are supposed to be of universal validity. Here the protocol of the (nearly) first contact. Yours Trestone: SEARCH: “Hello ALIEN, we are especially interested in your logic and mathematics and wether they are different to ours?” ALIEN: “Hello SEARCH, we do not have one logic or mathematics. We use different ones for different purposes.” SEARCH: “Can you give me an example for such a logic?” ALIEN: “Just give me some problems you want to handle, and we will find a suitable logic for you.” SEARCH: “First all statements should be either true or false and implications can be evaluated by analyzing the components. It should help for consistant argumentation and reasoning.” ALIEN: “Human classical logic would be a good choice, but not all statements would be either true or false. By the way we use this logic in communicating with you.” SEARCH: “With the execeptions, do you think of statements like the liar statement:“This statement is not true”?” ALIEN: “Yes, and with this logic you will have mathematical restrictions like the incompleteness theorems of Kurt Gödel or the set of all sets being no set.” SEARCH: “You know Kurt Gödel?” ALIEN: “We studied all that you have sended to us.” SEARCH: “As we tried to do. Could you show me a logic without the restrictions you mentioned?” ALIEN: “You could do it easily yourself: The logic “everything is true””. SEARCH: “Ok, that is true, but I meant a more useful example for practical purposes?” ALIEN: “We tried a “joke”! A logic of the kind you asked for is not to complicated but a little bit technically boring. You have to use additional dimensions. It is similar to solving the square root of -1 with complex numbers.” SEARCH2: “Just try do explain it to me. By the way I am a new human being, as my collegue died of old age.” ALIEN: “Hello SEARCH2! Perhaps we should give longer answers to you … For analyzing all three problems indirect proof is classically used. So there are statements which would be simultaneously true to their negations. In the new logic these statements (or more precisely their truth values) are in another dimension than the negations. We call this dimensions layers and the logic “layer logic”. There are indefinitly many layers k=0,1,2,3,… and every statement has a truth value in every layer. The truth values can be different in different layers. Classic statements are similar to layer statements that are constantly true (=T) or constantly false (=F) in all layers greater than 0. In layer 0 all layer statements are undefined (=U, a symmetrical starting) and we have “undefined” as a third truth value in all layers. All layer statements need a truth value in every layer and truth values do only exist for the combination of statements and layers. Truth values can be defined recursivly using already defined statements and smaller layers.” SEARCH2: “Let us try an example, the statement “This statement is not true”.” ALIEN: “First we have to add layers, as a statement alone has no truth value: “This statement L is not true in layer k”. Now we have to define a truth value for L in every layer. We do this by defining when L is true for every layer k+1 depending on the truth value of L in layer k: For every k=0,1,2,…: L is true in layer k+1 if L is not true in layer k and L is false else. With v(L,k)=T for “L has truth value true in layer k”: v(L,k+1):=T IF ( v(L,k)=F or v(L,K)=U ) ELSE v(L,k+1):=F We have v(L,0)=U as all statements are undefined in layer 0. v(L,0+1):=T IF ( v(L,0)=F or v(L,0)=U ) ELSE v(L,0+1):=F v(L,0+1):=T IF ( U=F or U=U ), therefore v(L,1)=T v(L,1+1):=T IF ( v(L,1)=F or v(L,1)=U ) ELSE v(L,1+1):=F v(L,1+1):=T IF ( T=F or T=U ) ELSE v(L,1+1):=F, therefore v(L,2)=F So we have v(L,0)=U, v(L,1)=T, v(L,2)=F, v(L,3)=T, v(L,4)=F, … SEARCH2: “What does this mean for the original liar statement, is it true or false?” ALIEN: “Not all layer statements are classical statements, the liar statement is one of those nonclassical statements. It has no classical truth value, but is a normal layer statement with alternating truth values. It is like a complex number that is not real. To get the benefits of layer logic you have to use it. SEARCH2: “But it is not easy for me to change to a new logic, for example if we talk about it we should use a known logic.” ALIEN: “Fortunately we can use human classic logic when talking about layer logic, as this logic is the meta logic of layer logic.” SEARCH2: “Is layer logic similar to the theory of types by Bertrand Russell?” ALIEN: “In the theory of types objects are splitted into differend types and the types are used to avoid self reference within objects. In layer logic the truth values are splitted into different layers and the layers enable us to have self reference within objects and statements. So the answer is mostly no.” SEARCH2: “Can you give an example for sets and self reference?" ALIEN: “So let us have a look on layer set theory, a rather nice piece of work. The central idea is to treat “x is element of set S” (x e S) as a layer statement: It is true in layer k+1 that set x is element of the set S, iff the statement A(x) is true in layer k. v(x e S,k+1) :=T if v(A(x),k) = T (and F or U else). And as in the original theory of Cantor for every set statement A(x) there exists a set. We have the following two rules for sets: Rule M1 (assignment of statements to sets): For all k,sets x,set M exists a set statement A(x) which fulfills: v(x e M, k+1) := v(v( A(x), k)=w1 v v(A(x), k)=w2 v v(A(x), k)=w3,1) with w1,w2,w3 = T,U,F or one or two of them. Rule M2 (sets defined by statements): For every layer logic statement A(x) about a layer set x there exits a layer set M so that for all k=0,1,2,3,… holds: v(x e M, k+1) := v( A(x), k ) (or the expressions of rule M1). You asked for examples: The empty set 0: We use “x e 0” as A(x) For all k>=0: v(x e 0, k+1) := v(v( x e 0, k )=T,1) (=F for k>=0) v(x e 0, 0+1) := v( v( x e 0, 0 ) = T, 1) = v( U = T , 1 ) = F v(x e 0, 1+1) := v( v( x e 0, 1 ) = T, 1) = v( F = T,1) = F, etc. The full set All: v(x e All, k+1) := v( v( x e All, k ) = T v v( x e All, k ) = U v v( x e All, k ) = F , 1 ) = T for k>0 and =U for k=0. v(x e All, 0+1) := v( v(x e All, 0) = T v v(x e All, 0) = U v v v(x e All, 0) = F, 1 ) = = v( U = T v U = U v U = F , 1 ) = T v(x e All,1+1) := v(v( x e All, 1) = T v v(x e All, 1) = U v v v( x e All, 1) = F , 1 ) = = v( v( T = T v T = U v T = F , 1 ) = T, etc. So other than in most set theories in layer theory the full set is a normal set.” SEARCH2: “What is with the Russell set, the set of all sets that are not elements of themselfes?" ALIEN: “We translate the definition of the Russell set R to layer set theory: v(x e R, k+1) := v( v( x e x, k ) = F v v( x e x, k ) = U , 1 ) v(x e R, 0+1) = v( v( x e x, 0 ) = F v v( x e x, 0 ) = U , 1 ) = T (U=F v U=U , 1 ) = T ; therefore v(R e R,1) = T v(R e R,2) = v( v( R e R, 1 ) = F v v( R e R, 1 ) = U , 1 ) = F (T=F v F=U , 1 ) = F; therefore v(ReR,3) = T, v(ReR,4) = F, ... R is a set with different elements in different layers, but that is no problem in layer set theory, so R is a layer set." SEARCH2: “I suppose that Cantor´s diagonalization in layer theory is not valid any more?” ALIEN: “You are right. The set of all sets All is in bijection (via identity) with its power set. So we do not need different kinds of infinity in layer set theory. But let us have a look into the proof of Cantor, transferred to layer theory: Be S a set and P(S) its power set and F: S -> P(S) a bijection between them (in layer d). Then the set A with v(x e A, k+1) = T := if ( v(xeS,k)=T and v(xeF(x),k)=F ) is a subset of S and therefore in P(S). So it exists x0 e S with A=F(x0). First case: v(x0 e F(x0),k)=T , then v(x0 e A=F(x0), k+1) = F (no contradiction, as in another layer) Second case: v(x0 e F(x0),k)= F then v(x0 e A=F(x0),k+1) = T (no contradiction, as in another layer) If we have All as S and identity as Bijektion F we get for the set A: v(x e A, k+1) = T := if ( v(x e All,k)=T and v(x e x),k)=F ) = = if ( v(x e x),k)=F ) This is the layer Russell set R (We omitted the ´u´-value for simplification) - and no problem.” SEARCH2: “And can we still do arithmetics?” ALIEN: “Yes, mostly as usual, sometimes in a special way. Let us start with the Peano axioms: We can define the successor m+ of a set m in the following way: v(x e m+, k+1) := v(x e m, k) v v(x=m,1) For k=0 without v(x e m, 0): v(x e m+, 1) := v(x=m,1) We start with m=0, v(0+,1) = v(x=0,1): In layer 1 the only element of 0+ is 0. v(x e 0+, 1+1) := v(x e 0, 1) v v(x=0,1) = F v v(x=0,1). v(x e 0+,2+1) :=v(x e 0,2) v v(x=0,1)= F v v(x=0,1) = v(x=0,1) So 0+ is a set with only element 0 in all layers >=1. Now we look at m=0+ v(x e 0++, 1) := v(x=0+,1): In layer 1 the only element of 0++ is 0+. v(x e 0++, k+1) := v(x e 0+, k) v v(x=0+,1) In all layers >1 the only elements of 0++ are 0 and 0+. So we find: n+ contains in layer 1 exactly the element n n+ contains in layer 2 exactly the elements n, n-1 n+ contains in layer n exactly the elements n, n-1, …,1 n+ contains in layer k>n exactly the elements n, n-1, …,0 For large k the natural numbers of layer set theory are therefore similar to the classical natural numbers. The (adjusted) Peano axioms hold for m+. We can define 0, 0+, 0++ etc., (the natural numbers) this way. The addition of numbers we define using the successors: v(x e n + m+, k+1) := v(x e (n+m)+, k+1) = = v(x e (n+m),k) v v(x=(n+m),1) Multiplication: v( x e n*m+, k+1 ) := v( x e n*m + n, k+1) = = v(x e (n*m + n-1)+, k+1 ) = = v( x e (n*m + n-1), k) v v(x = (n*m + n-1),1) v(x e 2*2+, k+1 ) =v(x e 2*2+2, k+1 ) =v(x e (2*2+1)+, k+1)= = v( x e 5, k) v v(x=5,1)" SEARCH2: “Can you give me more details in a special paper?” ALIEN: “You already have it: For first fundaments look at a Review of the logic of Prof. Ulrich Blau ( as it is a pdf-file, you may have to put this URL directly in your browser: https://wwwmath.uni-muenster.de/u/rds/blau_review.pdf ) and for layer logic at a thread by Trestone at ResearchGate: https://www.researchgate.net/post/Is_this_a_new_valid_logic_And_what_does_layer_logic_mean Or you may search “the net” with “layer logic “Trestone”“ or with “Stufenlogik Trestone” (in German). The symbolization there is slightly different: W(A,t) is used instaed of v(A,k). There still is no academic paper for layer theory – perhaps someone is interested to do this?” SEARCH2: “It will probably not be me, as my time is fading out …" AlIEN: “Hello SEARCH2, you did not ask a question?” ALIEN: “?” ALIEN: “Here an aspect that might be interesting for philosophers: The Münchhausen foundation trilemma (Agrippa`s trilemma), that there are only three poor choices to fundament and start our argumentations gets a new option with layer logic: If we assume that a reason has to be true in a higher level than the founded, the reasoning can go back not further than to layer 1. As every reasoning reduces the layers at least for 1, starting at an arbitrary layer we reach layer 1 after finite steps.” ALIEN: “?” ALIEN: “Hello, is there anybody out there interested to continue this communication?”

Calling this science forums and then using moderators that clearly don't understand science and having rules that restrict or ban the dissemination of scientific knowledge is an oxymoron. All the things you ask about can be done without electricity or anything all that fancy. Without laboratory glassware and proper thermometers it becomes more difficult but far from impossible. Making black powder is very easy and all the ingredients are easily located or produced virtually everywhere that any level of technology is at hand. Making nitroglycerin, nitrocellulose or guncotton and other high explosives is also quite easy. Even making primer materials is relatively easy. No special cooling is needed. Cool water from a mountain spring will work perfectly, but cold tapwater is just fine! And other methods also work if cool water isn't available. Charcoal is obvious. KNO³ or potassium nitrate can easily be leached from bat shit or reacted brick morter or even graveyard dirt! Sulfur can be obtained from pool chemicals, by burning iron ore, and many other sources. H²SO⁴ or sulfuric acid can be obtained from car batteries. Nitric acid is the hardest. But one good way in a pinch is to get nitrous oxide from a dentists office and pass it over a damp bed of heated quick lime. Bubble it into a beaker of mineral oil. A red oily liquid will build up under the oil. That's nitric acid. Both the nitric and sulfuric acids will need to be concentrated quite a bit before they will work to make guncotton or nitroglycerin. Primer can be made with nothing but concentrated nitric acid and mercury! Just thirty years ago it was common for boys with a scientific bent to make and experiment with these things. They are dangerous but they are no where near the world ending hazards that some here make of them! I did all these things when I was a kid. Fooling around with these things is still completely legal in the USA. Just don't get any crazy ideas or make a huge stockpile.... If you want more info feel free to contact me. I can tell you every aspect of recreating basic technology in an apocalyptic scenario.