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Following on from @Moontanman's thread on a new nitrogen-fixing organelle, I started wondering how biological nitrogen fixation first arose at the dawn of life. I found the linked paper, which I thought very interesting on the subject: https://www.sciencedirect.com/science/article/pii/S0966842X23000914 The writers focus on the metal atoms (or metal/sulphide complexes) which are at the heart of nitrogenases, which can bind nitrogen, lower the strength of the triple bond and progressively add H+ and electrons to form eventually 2 molecules of ammonia. There are 3 variants of nitrogenase, one using just Fe, one using Fe and Mo (molybdenum) and one using Fe and V (vanadium). I was surprised to see these 2 transition metals have such a biologically important role, but there you go. It seems there is evidence the first nitrogenase appeared in the Archaean, before the Great Oxygenation Event (i.e. global-scale photosynthesis), which I suppose is not a surprise, seeing as a lot of life would be needed to geo-engineer the planet, and that would require a lot of fixed nitrogen. They suggest that, before the GOE, there would have been a lot of Fe²⁺ in the oceans, whereas under oxidising conditions this would go to Fe³⁺, the salts of which tend to precipitate from aqueous solution, so would be less bio-available. So a system incorporating Fe is not hard to explain. Curiously, though, phylogenetic analysis suggests that the version incorporating Mo as well as Fe was the first to appear, even though the concentration of Mo in the early ocean was apparently very low. That version has better kinetics, which may have favoured it, but it still leaves open the issue of where the Mo came from. They speculate that there may have been higher local concentrations in the zones where the first nitrogenase arose, perhaps in hydrothermal vents. But this is very much open-ended and needs further research. By the way I found the chemistry of these nitrogenases really interesting. There seems to be some very unusual chemistry, involving bridged hydrides to supply the extra electrons needed for the reduction. But that's another subject. It seems the evidence is that nitrogenases are an "evolutionary singularity", meaning this little family of 3 closely related variants, using the 3 metal combinations mentioned, seems to have evolved once only in the whole history of life on Earth. But absolutely vital to the whole enterprise of course.

! Moderator Note Please step off the soapbox and make your way to the door.

Far be it from me to question this, yet the paper itself offers strong evidence of the early appearance of Mo based BNF which implies that Mo was definitely available to life in the oceans. Something of a paradox. Molybdenum is not a rare element, especially around hydrothermal sites. Perhaps its low apparent oceanic concentration at that time was a reflection of an intense biological demand that kept it locked up in biomass. Just a thought.

One of Oliver's best reports. Re secrecy, my feeling has long been (based on endlessly recurring news of government leaks) that the federal government is incredibly bad at keeping secrets and couldn't maintain a decades-long conspiracy if their lives depended on it. At best, they draw across a veil that's supposed to be a blackout curtain and only achieve a smudgy shower door. If nothing else were to leak on a particular investigation, allow some time passing and glitches in chain of command and you will get bureaucratic bungling. Or an Ed Snowden. Or both.

Your right I didn't bother responding to your logic. As I stated I lost interest. Particularly when you have statements such as information travelling faster than c that you cannot back up with any real physics or mathematics. This includes your holonomic toroid allowing a faster than c wave. This runs counter to well known and understood physics. So any logic based on this is meaningless if you cannot show how that's even possible under mathematics using known physics. Another example is some mysterious toroid travelling at c. It must be something massless to do that. However you can't describe it beyond your verbal claims. I also have no interest in downloading a paper from an outside source when the rules requires that material to presented here.. Who knows you might catch my interest once you start applying some real physics or mathematics. Rather than nothing more substantial than your logic

James Olivier had his 'Last Week Tonight' about UFOs. There is amongst others the footage of Edward Condon in it, saying exactly what @Moontanman cited. And I completely agree with Swansont about Avi Loeb. His (Loeb, of course... ) first hypothesis always seems to be 'aliens!'. And then do everything, however ridiculous, to support this hypothesis. No, this is not the way doing science and the article Swansont links to is a perfect description of Loeb's problematic stance and way of investigating, unworthy of science. I think it is very bad, it undermines the reputation of science.

I believe the iron clusters got oxidized and destabilized under oxygen. CO is also an inhibitor and it actually binds to nitrogenases like haemoglobin, IIRC. As a side note, oxidizing and often destabilizing iron cores is one of the ways many organisms sense oxygen and quite a few regulatory factors related to oxidative stress (and also iron metabolism) are using that. Well, you could have started them! I am just sitting here, looking at physics threads and pretend to understand what swansont is explaining.

Firstly; game theory is applicable anywhere you find language being used. Obsolescence is actually the main reason humans will give up a technology... in fact that seems to be the only reason. I have researched and researched and have not found any historical example of a technology we are both reasonably certain existed, didn't just lose the blueprints of etc, and actively gave up. One potential exception is flexible Roman glass, the inventor of which was apparently executed so as not to devalue the gold and silver industries. Don't know how true that story is. However, humans have in the past given up something that in some ways only gave them power while giving some very obvious national security issues and issues of morality. Slavery. We also gave it up at the cost of an entire industry that in today's money would be worth billions. In terms of there being a massive harm and the risk of national self harm involved; Slavery and using nuclear weapons could be compared to some extent. Dammit. There was me hoping to avoid Hegels Master and slave dialectic. Rounding back to what I said earlier about obsolescence. I feel that a direction public opinion could steer militaries to go; is the obsolescence of nuclear weapons through the technological advancement of precision in war over destructive power. Lets give the military eggheads a very small pat on the back for the whole scientific achievement of maximising destructive capabilities. Knocked that one out of the park, next challenge. Can you make a small bomb that can fly up a generals nose? Maybe the global zero initiative should open up two fronts instead of just one. Make it a forced military standard to reach as close to global zero civilian/non combatant deaths in war as is possible.

Yes. The expanding time only metric is flat, whereas the FLRW metric is not flat, so there is no coordinate transformation between them. In this thread, I demonstrated that an expanding space and time metric does not exist as distinct from an expanding space only metric. I did this by showing that an expanding space and time metric can be transformed to an expanding space only metric by a coordinate transformation, thus proving that they are physically the same. Mathematically however, the manifestly conformally flat form of the metric is useful for two reasons: 1, it indicates that the Weyl conformal tensor field is zero (the Weyl conformal tensor field represents pure gravitation, and therefore the only gravitation in the flat space FLRW spacetime is that which is intrinsic to the energy-momentum tensor field itself); and 2, it simplifies the equation of light-like geodesics (though this also assumes the homogeneity and isotropy of the FLRW spacetime¹). My most recent post in this thread demonstrated that there are limits to what coordinate transformations can do. By showing that an expanding time only metric can be transformed to a flat spacetime metric by a coordinate transformation, I established that it cannot be obtained from an expanding space only metric, which is not flat, by a coordinate transformation. It is worth noting that any metric of the form: (ds)² = T(t)² c² (dt)² – X(x)² (dx)² – Y(y)² (dy)² – Z(z)² (dz)² describes flat spacetime. The following coordinate transformation exists between this metric and the Minkowskian metric: t' = t'(t) ; x' = x'(x) ; y' = y'(y) ; z' = z'(z) where t'(t), x'(x), y'(y), and z'(z) are solutions to the differential equations: dt'(t)/dt = T(t) dx'(x)/dx = X(x) dy'(y)/dy = Y(y) dz'(z)/dz = Z(z) ¹ Although the equations for the light-like trajectories in the manifestly conformally flat form of the metric given earlier in this thread are indeed light-like trajectories, I did not prove that these are geodesics. To prove that they are geodesics, note that in the two-dimensional tx-spacetime, the light-like trajectory passing through a given point from a given direction is unique, and therefore must be geodesic. But to prove that in the four-dimensional spacetime, the light-like geodesic doesn't deviate from the two-dimensional tx-spacetime, the symmetry arising from homogeneity and isotropy can be invoked, requiring that the unique light-like geodesic remain in the two-dimensional tx-spacetime (symmetry breaking can only occur if there are multiple solutions).

There isn’t going to be more information in those reports as time goes on, so I don’t see how this analogy is relevant. Research will move toward success if you improve the quality of the research, as I’ve pointed out numerous times. You keep harping on ridicule - and suggesting it’s systematic - without presenting evidence of it. Pointing out the poor quality of data and the nonscientific approach is not ridicule, it’s a statement of fact. True skepticism is part of science.

I just read some comments on the video. Seldom had more fun. Here a selection: This woman is a legend, first clear UFO footage in history Finally a clear picture of a ufo instead of the usual dark and blurry images (Eise: yup, therefore it was so easy to recognise) This is the best clearest footage of UFO I have ever seen. US Government: "Relax it's just a weather balloon." (Eise: no, it was't...) Literally the best footage of a “ufo” to date …bravo!! U guys deserve something as a news station SERIOUSLY! probably the best video/picture caught of a UFO ever lol 1. It wasn't fast, the aircraft was, that's why you see it zipping through the video. 2. It's a blade propelled object judging from its inclination, probably a drone. 3. The drone was operated by the government or related agency because even considering how dangerous this was for the airliner, no news about investigation had been announced. Why is everyone so scared to say what it really is?? (Eise: because it would shock your world view) That’s our own government. Stop Do you really think you caught it on your home camera and the government doesn’t know? They have been here for thousands of years. Cylinder Aka cigar shaped crafts are one of the most common UFOs. Legit sighting in my opinion. Great catch.. (Eise: obviously a real expert!) This is one of the best UFO footage in recent decades (Eise: his emoticons, sorry that they became so big...) Etc etc. Naivety, conspiracy theories... There are however a few who notice that it looks to fly fast, but that it could be the speed of the plane. Some examples: The plane flying at 2 to 300 miles per hour, if you look closely, that object could have very well been stationary given the travel direction of the plane if you look at the land while it's flying and how the object seems to fly by at a high speed but could very well be almost sitting still. Black balloon with helium? It’s not moving, you are. (Eise: close, very close...) And the price goes to:

Sorry to disappoint, but I recognised it immediately: The speed is the speed of the plane. It was 'a close encounter of the daily kind'. Blow it up in a cool place on a hot day (inside your home or in the shadow), bring it into the sunlight, until it lifts and let it go, and you will never see it again. From this Swiss site. Costs 12 Swiss bucks. What a fuzz about a funny, but physically interesting toy. I once 'launched' one. Ah, there is even a wikipedia article bout it: That was a fast +1, Moontanman. Small correction: blow it up on a cool but sunny day. Obviously there also much bigger ones...

I think this is where a misunderstanding arose, as the discussion shifted away somewhat from the OP. I take your and @toucana point as to where the thread started, so I didn't make clear that I thought the thread had moved a bit and was trying to follow that. My point goes to the substantial difference (especially re the fate of Earth's supporting ecosystems) between any nuclear exchange and all the other historical forms of massive death you described. I won't rehash that, but anyone who wants to review previous posts is welcome to. I agree there is a legitimate moment of self-defense in a war, but I tried (and failed) to make some points as to how a nuclear "defense" can ultimately kill so many people who are not attacking. Therein lies the problem of proportionality, as well as Geneva issues, plus the migration of radionuclides and weather effects to friendly nations, also addressed by me and others. Again, I didn't communicate well that I see this as more than just a form of the Trolley Problem, because of the unique implications of annihilating an entire (or several entire) cities (and what that opens up, in terms of a larger war). We don't have to explore them here. I gave it a shot, but will step aside so others can resume with the original question.

It is the equation. a(t) = V(t)/s(t)^2 or miles/hours^2 aka mph^2 Position=S(t)->(distance over time) Velocity=v(t)->s(t)/time Acceleration=a(t)->v(t)/S(t)->distance/time^2 Time squared, yes it is covering the same distance over more time. Hence the outside world is experiencing a greater passage of time. Whether or not the observer is experiencing more time as well is a matter of debate. We really can't go fast enough to tell.

Here's why the math is irrelevant. I do not know how to quantize the toroid's precessional movement but the variables it will require are in the definition of the shape. To accomplish the quantization, the mathematician will have a near infinity of options when assigning delta in XYZ to the different hidden variables represented by the measurements of the Toroid. The proof that it is the theory of everything is logical, not mathematical, because there will be many different ways to setup those variables so as to purposely represent a specific experiment's superposition space. This is the logical proof: 1. 3d is logical and the entirety of evidence points to 3d. 2. The Holonomic Toroid can represent the quantum in 3d. It's the only shape that can. That's it. I don't need to provide a mathematical solution because the problem was logical and tautological, not quantizeable. It has been fully quantized. What was missing was a unifying logic. Moreover, even when someone does the math, it will not prove that the shape is what is there. It will only prove that the specific configuration can be molded to the superposition space. To PROVE it, as a scientist, one would have to design a 3d falsification experiment, in 3D.