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Showing content with the highest reputation since 12/31/22 in all areas

1. Homophobia, nature or nurture?

I suspect distaste for homosexuality is inborn in many of us. Given that we have a drive to be attracted to the opposite sex, we find the idea of sex with someone of the same sex a big turn-off. Consequently we may find the idea of a sexual approach from somebody of our own sex rather disturbing. If that is homophobia, then I am a homophobe. It seems to me that the blanket term "homophobia" is thrown around too easily. One needs to draw a distinction between personal sexual taste and the attempts by some to condemn different (minority) tastes in others. It is the latter that society should refrain from.
5 points
2. OT posts split from New theory of evolution

People should start adding a new section to their resume/CV, 'Prior reincarnations.'
4 points
3. Do you believe the USA really landed on the moon?

What difference does it make what anyone “believes”? I always felt that the best response one can give to MLHs isn’t scientific at all, but political - the USSR and Maoist China believed it to be real, and that’s to say an awful lot given the global political, military and intelligence situation back in the day. Had this been fake, you can be absolutely sure that the communist bloc would have found out about it, and oh boy would they have had a field day with that
4 points
4. dark matter question

The first thing to keep in mind is that while 90% of the mass of our galaxy is estimated to be dark matter, This includes the entire DM halo or a spherical volume that extends well beyond the visible matter disk of the galaxy. Once you spread it's mass throughout that huge volume, you end up with an extremely low density. The other thing is that even though, if you were to take the total mass of the solar system and spread it out evenly throughout a spherical volume enclosed by Neptune's orbit, you would end up with a overall density that would put a man-made vacuum to shame, it would still be many many times denser on average then, say, a 10 parsec radius sphere in our part of the galaxy. And that 10 parsec sphere would, still contain more regular matter than DM. It is estimated that the total mass of DM in the Solar system is equivalent to that of 1 small asteroid. Even a 10 fold increase in this density would be insignificant gravitationally to the Solar system. If this is the case, then how is it that DM can cause discrepancies in the rotation curves or galaxies? The visible matter in galaxies like the Milky Way is concentrated in its central bulge and thin disk. So if you calculate orbits based on visible matter, you need to take this distribution into account. DM however, is spread out spherically, and the vast majority is "above" and "below" the galactic disk. And any mass closer to the center of the galaxy than a given star, has a gravitational effect on that star's orbit around the galaxy. So, for example, if we take that 1 small asteroid's amount of mass spread out throughout the Solar system, and apply that density to the volume of the sphere contained within the Sun's galactic orbit, you get a total mass of DM that is a significant fraction of the total mass of the visible mass of the Milky way; enough to have a noticeable effect on the Sun's galactic orbit. The upshot is that star systems like the Solar system are "matter rich dense spots", which makes their internal orbital mechanics essentially immune to the kind of DM density variation likely to occur.
4 points
5. COVID-19 Is No Longer a Public Health Emergency?

It is partially true, but perhaps not universally so. A few key points, the dying from and with COVID-19 can bit a bit muddled, depending on whether a give jurisdiction separates that data. Looking back at 2022, the omicron waves have hit countries quite differently and I think what we start to see is a change in the immunity status of the population. For example, for Canada 2022 was the deadliest year yet, as Omicron has swept the country and reached vulnerable populations that were not exposed during the less contagious waves (in conjunction with public health measures). Now that Omicron has infected the majority of the population basically everywhere, the hope was/is that they may be more resilient when it comes to severe disease. Some data seems to show that with some areas having relative constant, COVID-19 specific hospitalizations, despite having increasing infections when new variants arrived at some of the areas I have looked at. In However, there are several issues with that. The biggest in my mind is that national data is at this point not terribly useful if you want to understand public health impact. In my mind, at the latest since Omicron the risk has shifted from individual risk, to population risk. Due to the massive and still not abating spread of Omicron lineages, our health care system is now systemically impacted. This includes obvious parameters such as hospitalization and death, but also increased risk of infection in vulnerable folks (e.g. cancer patients, immunosuppressed individuals, diabetic folks or otherwise vulnerable to inflammation). Whether you are hospitalized with or because of COVID-19, SARS-CoV-2 can cause complications. On top, we have lingering effects of sever inflammation and other issues, which ultimately put an almost constant pressure on virtually every health care system in the world. This has a ripple effect, resulting in excess health burden that simply would not exist without COVID-19. Especially in low population density countries, outbreaks have vastly different impact on the health care system, too. I.e. if the next hospitals is hours (or days!) away a few missing beds due to COVID-19 hospitalizations can have vastly more impact than in area where folks can be shuffled between hospitals, for example. So in aggregate I would agree that the COVID-19 situations is, as a whole, in a different situation than at the beginning of the pandemic, with rapid mass deaths being less likely (at least so far). On the other hand it is still a bit of a semantic trick. Even if we do not think of it as an emergency, folks will die on a daily basis, we will have continued pressure on our health care system and our overall health is still going to be impacted. Perhaps one can think of it as the aftermath of a Tsunami, folks are less likely to be swept into the ocean now, but if thinks are not fixed, risk of cholera and other issues will increase. There are also a couple of rather bad takes from the author of the article that I do not agree with. For example the assertion that the daily deaths in the US are comparable to a bad flu season does not take into account that those numbers would represent about 3-4 months of flu. In contrast in the post-emergency situation of COVID-19 that is rate that is mostly non-seasonal (i.e. continues throughout the year). I am also slightly perplexed why he picks out Denmark, when I believe the UK actually has actually segregated data. A quick check shows me that pre-COVID-19 England had somewhere between 1-2k deaths per year. In 2022 about 18k cases had COVID-19 as cause. Even if that was not stringent enough, and we cut it by half, at least for the whole year the situation does not seem that great. And I would also add that flu is not harmless. There is a reason why health authorities beg us to get vaccinated every year. And having two serious diseases circulating is going to put further strain on our health care systems. The tragedy is that once we move off the ledge, many think that the thing is over and it is time to have a picnic. In truth, the cliff is crumbling, and has for a long time, regardless whether we call it an emergency or not. Edit: I clicked through some of the links in the article and my assessment on the article is not improving. Some might be just mislinked, as they do not seem to show the data the author was citing. But perhaps worse, he is citing an author who publicly made false statements on COVID-19 and vaccines. I am not saying that the overall thrust of the article is inherently wrong, but the way it is built looks too much like cherry-picking to me. And if I were to write an opinion piece, I would stay the heck away from folks who have promoted falsehoods. Edit 2: One of the things I feel that is missing is an honest discussion of what kind of disease burden we, as a community, feel acceptable. This includes direct damages due to the disease, but also disruptions in our health care and related factors. Howe much are we willing to spend vs what kind of damages (including deaths) do we feel is justifiable for a given price? Edit 3: I should add the disclaimer that I am not an epidemiologist nor do I work on public health systems. As such this is really just my opinion based on my work and interactions with local health authorities as part of related projects.
3 points
6. Do fish dance?

Yes. If you turn up the bass.
3 points
7. Homophobia, nature or nurture?

I’d say a feeling (or any kind of mind-state in general) is never in itself reprehensible, because it is the result of very many different internal and external causes and conditions that we generally do not choose to put in place. What we can choose though - at least to a degree - is how to act in response to our mind-states. Thus, merely having personal distaste or discomfort over anything is ethically neutral, whereas (eg.) beating someone to a bloody pulp because of such mind-states, is not.
3 points

Except that 'Present Reptiles' are not descended from dinosaurs. The lineages that were to become lizards & snakes, turtles & tortoises, the tuatara and the crocodilians had all split off from the sauria/archosaur line before dinosaurs were a thing..
3 points

3 points
10. Time and relativity (split from The Nature of Time)

Calculating the total time dilation when there is a combination of differences in gravitational potential, as well as relative motion, is a standard exercise that’s done in most undergrad courses on GR. It’s not that hard so long as you can use the Schwarzschild metric, which is highly symmetric. Usually it’s done in the context of GPS satellites, because the software on your GPS receivers has to explicitly account for both these effects. At an orbital height of ~20000km and a relative speed of ~3.9km/s wrt to the ground observer, the gravitational contribution works out to about $$38 \mu s$$, and the kinematic contribution is roughly $$7 \mu s$$. Because of the symmetries of the Schwarzschild metric, you can just add these together to get total time dilation. That’s like saying we have never been on the surface of the sun, so we don’t really know it’s hot. It’s a silly argument. We have had a large number of crafts of different kinds both on the surface of the moon, and in orbit around it. We have also bounced lasers and radar signals off the moon’s surface. All of these things explicitly take into account time dilation - it affects orbital mechanics, it affects light travel times, and it affects frequency shifts. No discrepancies with expected physics have ever been observed in that regard. True, we haven’t done that specific experiment you are suggesting - but we have done many, many others where time dilation plays a role too, so if anything unexpected was going on, we would have seen it long ago. Why is the movement of a planet/star/moon different from the movement of a satellite? Then why do you insist that this experiment must be conducted on the moon? It’s not the total amount that’s the problem, but the cost/benefit ratio. All the above were designed to observe specific phenomena, which our models indicated should be there, so these are direct tests of specific predictions. On the other hand, what you are suggesting is a wild goose chase - there is nothing whatsoever to suggest that anything out of the ordinary will happen if we perform that experiment of yours, because motion and gravity isn’t any different on the moon than it is in Earth orbit. Research funding in fundamental physics is a very limited resource, so we are careful where we invest it. Like I said, if you want to test time dilation on the moon’s surface with respect to an Earth observer, then bounce a laser or a radar echo off it, and compare propagation times and frequency shifts to what our models say they should be. It’s a much easier test that addresses the same issue of time dilation, and it’s been done many times since 1946 - Earth-Moon-Earth communications is in fact an entire sub-discipline of aeronautical engineering. Sure. I’m not opposed to performing such ann experiment, if anyone wants to provide the necessary funds. The more tests of GR/SR the better, so far as I am concerned. I just think it would be a waste of money, since there are much easier ways to test the physics in question here. Wrong, see above. The radar echo “Moon bounce” is a direct test of this (radar echo goes Earth-Moon-Earth), because any discrepancies in predicted time dilations would show up as anomalous frequency shifts in the reflected signals. Needless to say, no such thing as ever been observed. Yes, I’m denying that, because it’s a pop-sci misconception. Look at Newtonian gravity - there are any number of experiments that are in direct contradiction to what this model predicts. And yet, we are still using it very successfully, and we are even teaching it to our kids in school. The point here is that all models have a domain of applicability - a set of circumstances which they are able to model very well. So long as you stay within that domain, the model will continue to work for your purposes, just as Newtonian gravity continues to work for us within its domain of applicability, even though it’s been experimentally “disproven” in many different ways. And so it is with GR - we have already know for a long time that its domain of applicability is limited; we’re just not entirely sure precisely where those limits are. So if some experiment comes along that contradicts GR, then in the first instance we will tighten those limits. But it won’t ever be abandoned - that’s never going to happen, because it has already proven far too accurate and useful. That’s true. But it’s also dangerous to become obsessed with a single tree, and forgetting the rest of the forest - which is what you seem to be doing here.
3 points
11. Aphantasia is not a real condition

This thread is just bizarre, to be honest. I am autistic, and have been involved in the neurodivergence community for quite some time, both on a local and an international level. Aphantasia is a relatively common comorbidity for people on the spectrum; I personally know 3 (maybe 4) fellow autistic people who have this, and my social circle is by no means large. Even among the general neurotypical population, this isn’t rare - there has been a study conducted on this only a few months ago: https://www.sciencedirect.com/science/article/abs/pii/S1053810021001690 Evidently, aphantasia and its opposite - hyperphantasia - are very much real. Claiming otherwise isn’t just ignoring the evidence, but - and that’s much worse - it is dismissing and invalidating the suffering and challenges of those who have it, because this has a very real impact on people’s lives.
3 points
12. Aphantasia is not a real condition

I think the context was clear. One cannot universally assert what other people experience or don't. Your incredulity is not sufficient evidence to justify your position. Also, why must it be a 'condition' when it's just a different neural architecture in reality. The absence of said function may lead to other constructive abilities to evolve through necessity. Neuroplasticity is a thing
3 points

3 points
14. Here is a maths resource for those looking for Maths Tutorials

Here is a maths free resource for those looking for Maths Tutorials, from the Centre for Innovation in Maths Learning. The two links give the centre's home page, a topic list. https://www.cimt.org.uk/ https://www.cimt.org.uk/projects/mepres/alevel/ These are first class resources available for download in pdf.
3 points

Er, well, mastodons, sabre-toothed tigers, etc. appeared about 40m or more years later, from the Miocene onwards. The mammals that existed at the end of the Cretaceous were indeed small and shrew-like.
3 points
16. Early Human spreading on earth

Here's the paper with the find that Denisovan ancestry reveals two distinct pulses of Denisovan genes: https://pubmed.ncbi.nlm.nih.gov/29551270/ And here's a paper based on applying Bayesian methods with a bundle of plausible models as contrasting hypotheses, and finding that there seems to be support for a "third" --meaning distinct, but genetically equidistant between Neanderthals and Denisovans-- group of humans: https://www.nature.com/articles/s41467-018-08089-7 I learnt about these papers in this wonderful podcast by Stefan Milosavljevich: I always think twice before recommending a YT channel. This one is prime quality. Número uno...
2 points
17. White Supremacy in Chemistry - Apparently

To add to that, the Journal in question also publishes experiences and method used in courses, and often looks at things like how to conduct a course (especially experimental courses), how it is received by students and so on. Taking a look at the paper proper, the intro has a lot of fluff which is unusual for STEM papers, but not uncommon for sociological articles. But the core of the course really appears to be more about historical issues in science and how they might translate into modern sciences. I.e. it seems to be a course for STEM students rather than a creating a new framework of teaching chemistry to students (I do find the paper, as a whole, to be poorly written). Topics being covered are background in feminism (take it or leave it, I guess) but more interestingly, how politics and history motivated certain types of research and conclusions. These includes many of the typical cases folks learn in bioethics, such as non-consensual experiments on minorities (whose consent matters?), social Darwinism (extrapolation of scientific concepts to benefit certain power structures), the imbalance and lack of research in women's health and the undervaluing of female researchers. I am with Arete that the framing of the course is not ideal, but the material itself seems pretty inoffensive to me and is actually critical to improve sciences, probably with some more relevance to biomedical sciences than chemistry, but there is some overlap there, too. I think the point that the authors try to make is that the frameworks develops in sociological sciences can be helpful to contextualize the information we create in sciences and to at least acknowledge that these are not pure intellectual pursuits free from our current political and cultural situation (folks working on climate change might have a word or two in that regard. Or evolution. Or vaccines.)
2 points
18. White Supremacy in Chemistry - Apparently

1) The article is unequivocally about the pedagogy and teaching of chemistry at a tertiary institution in the United States. Whatever your thoughts on its broader sweeping implications for the philosophy of science, that is clearly, explicitly the framework in which the article is written. 2) It is written in a broader climate where there is increasing acknowledgement, specifically in the United States, that traditional pedagogical and teaching methods of college teaching are implicitly biased to favour/disadvantage individuals from different backgrounds. There's currently a broader discussion of this in the literature and college communities in which this particular article is written; eg. https://www.sciencedirect.com/science/article/abs/pii/S002210311530010X, https://aip.scitation.org/doi/abs/10.1063/1.5110152, https://www.tandfonline.com/doi/abs/10.1080/1360144X.2019.1692211 3) The article is poorly written in the context it is clearly aimed at. It's buzzwordy and reactionary in the language it uses, rather than objective and reflective. This leads to it reading like it is suggesting that science/knowledge itself is biased (which is ridiculous), rather than the methods of teaching/communicating it, which is what the broader body of discussion on the topic addresses. 4. The language example was simply one of convenience. You can also look at the use of traditional classrooms when some of the class has spent most of their lives outside, or written vs oral exams for students who grew up in homes with books vs not, school year structure for students with unstable vs stable housing, etc etc etc. Then you can look at the impact of varying pedagogical styles, like flipped classrooms, active learning, open air lectures, etc etc etc. The article in question is attempting to speak into an ongoing conversation with many points of merit. The article in question, however, is not very good.
2 points
19. White Supremacy in Chemistry - Apparently

Storm in teacup. People devoted to Feminist or Race Studies will tend to make every issue they explore about patriarchy and misogyny and racism. As Socialist idealogues make everything that is wrong about Capitalists and Capitalist ideologues make everying wrong about Socialists. A lot of the media can't help themselves; they trawl for people saying stupid or outrageous things that press people's buttons, in order to press people's buttons. Otherwise no-one would care what those people say, certainly not chemistry faculties. Encouraging participation in chemistry irrespective of gender or race or religion is mainstream reasonable and widely supported.
2 points
20. A plane made of plants

A small spanner here. A large part of a living tree is dead. If the outer layers of the tree remain intact, the heartwood will not decay, even though it is dead and retired sapwood. Some believe heartwood must be the most important part of the tree due to the fact that it is called “heart”. However, the name just refers to the central position of the heartwood in the tree. 27 Sept 2019
2 points
21. Aquatic ape hypothesis

Many inland peoples (eg African Bushmen, Australian desert Aborigines) who lived for many generations without any access to sea-foods have been healthy with fully working brains; the idea that early hominids couldn't develop large brains without an aquatic lifestyle sounds doubtful to me.
2 points
22. White Supremacy in Chemistry - Apparently

To piggyback - the abstract in the OP is poorly written, but I think what it's trying to say is that there is implicit biases in the way chemistry is taught, that favor/disadvantage students based on social/racial background. As CharonY points out, notations assume familiarity with a Phoenician alphabet and a periodic table originally written in English. This has the potential effect of implicitly biasing the learning of traditional chemistry to favor native speakers of Germanic languages. While a redox reaction remains the same whether you describe it using scientific notation, Sanskrit or pelvic thrusting, the way a student is expected to describe it on a exam usually has an underlying set of implicit assumptions and biases. While identifying such biases and altering pedagogy to level the playing field is a worthwhile endeavor, calling such biases "white supremacy/white violence/etc" is pretty eye roll inducing and something I personally think detracts from and diminishes the actual goal of identifying and ameliorating implicit bias from education and society at large.
2 points
23. Buoyant force

To see if you have understood it right, think about the following question. Take a pencil 20 cm long and 0.5 cm thick. Compare the buoyancy in these two cases: 1) you push it under water while holding it vertically, 2) you push it under water while holding it horizontally. In the case 1, the pressure difference between the water underneath and above the pencil is greater than in the case 2. Is the buoyant force different in these two cases?
2 points

2 points

2 points

2 points
27. Should I Learn C, C++, Go, or Rust?

Use the right tool for the right type of work you intend to do. If you want to write end-client Windows applications (freeware,shareware,commercial, sold to individuals or companies) then you should consider using C/C++/C#/C++ Managed If you want to develop front-end web-server applications (installed on a virtual hosting service) then you should consider using PHP (it will generate HTML, eventually CSS, eventually JavaScript, eventually other file-formats). PHP is installed on all/most virtual hosting services (other technologies are not) If you want to develop back-end web-server applications (installed on a dedicated server) then you should consider using Bash, Python, Perl, CGI (obsolete, it's compiled C/C++), jNode (server-side JavaScript) and endless list of new technologies. Actually, you can use any language to generate HTML/CSS/JS for users (visiting WWW), because you own the dedicated server and can install anything (unlike virtual hosting, where you are limited to the software installed by the IT company where you bought the hosting). If you want to develop applications for smartphones then you should learn (Android) Java, Kotlin, (iPhone) Swift. To start, install Visual Studio Community https://visualstudio.microsoft.com/pl/vs/community/ and use one of many template projects. Nowadays, people use GPUs (OpenCL,CUDA) to accelerate applications.
2 points
28. White Supremacy in Chemistry - Apparently

Institutions, that teach or place, scientists, can , and often do, have biases. The science itself, can not.
2 points
29. T-Rex smart as a baboon?

Sure. Another thread I had in mind was not on dinosaurs, but on numeral systems:
2 points
30. Reproductive organs shape

Many compromises are involved. Just considering bird's eggs. Burrowing birds tend to lay nearly spherical eggs which optimises content volume / shell area, or more particularly shell calcium content as a birds calcium reserves tend to be a limiting factor in egg production. This is also the strongest shape for a given calcium budget. Cliff nesting birds tend to lay highly pyriform (pear-shaped) eggs that tend to roll in a tight circle helping to prevent them rolling off the edge and also positioning the air bubble in the egg close to where the oxygen hungry brain and eyes will form. For active fliers, aerodynamic requirements produce a strong adative pressure to form eggs that present a low cross-sectional area against the direction of flight and this favours a more ellipsoidal shape (prolate spheroid to be pedantic). Most species fall in between these three idealised geometries with the balance being optimised for each one's characteristic lifestyle.
2 points
31. Reproductive organs shape

You realize that 'oval' is derived from the Latin word for egg ( ovum ) ? ( what a relief; I thought you were asking about your mis-shapen penis )
2 points
32. My analysis of Brexit: BRUS is the next big thing on the blocks.

The Scots and Welsh know the US would recolonize the UK. You spend far too much on public interests like healthcare, you only have like 50 billionaires, and your workers want fair accommodations as if they were really important. You participate far too much in your own economy with all that vacationing, and all that history is bogging you down with old buildings and protected reserves. We can show you how to pave over England's pleasant pastures so you can be just like us!
2 points
33. Consciousness Always Exists

I personally have no use for your diluted version of consciousness. It is so broad as to make it impractical. Similarly, I don't want to read an article about how shoe laces are made that starts with the assembly of Pangaea.
2 points
34. why are religious people mocking the big bang and evolution theory?

Peoples' identity is often tied to the group they belong to. It is incredibly important to be a part of that. That is where your friends are. You have a lot invested in the group. If you deny the beliefs of your group you are ostracizing yourself and cutting yourself off from an important part of your life. For many people it is better to not look too closely, or to entertain questions which in the long run can do you harm. I overlook things my family members do that I would find unacceptable in others. People vote for candidates in their political party who are clearly unqualified. It is a lot more common than many people recognize.
2 points
35. Controlling a volcanic eruption to stall climate change?

If it were absorption within the atmosphere that energy would be added to the atmosphere. It isn't absorption. This appears to be the correct option. As I understand it gaseous Sulphur Dioxide is the precursor to droplets of sulphuric acid that are reflective to sunlight. Being initially gaseous probably makes it easier to get pushed high in the atmosphere by volcanoes and for the resulting droplets to linger there, up to 2 years and global in effect. Human sources ie from fossil fuel burning rarely make it that high and have residence times of a few days and is more regional in effect. From NASA - This source doesn't specify the altitude of the clouds, but sounds like it has a reflective cooling effect. Regarding the initial question(s) - First, we don't know how to get volcanoes to erupt on demand or continuously. There are proposals for deliberately adding sulphate aerosols to the stratosphere but with (usually) aircraft, not via volcanoes. Sulphate aerosols aren't dust. Not sure dust is such a highly significant factor - probably doesn't linger long enough. But, to echo MigL, massively increasing volcanic activity seems counterproductive. The cooling effect of aerosols depends on the rate you keep adding, whereas global warming is dependent on the accumulated total of CO2 (over the timescales that matter). It doesn't fix the cause, just masks the effects - and the consequences are more complex than simply reducing global warming, ie may induce significant unwanted regional climate changes. My view is that - given existing climate politics - anything gives the illusion that we can keep burning fossil fuels at high rates and avoid the climate consequences is unhelpful - even where those attempts are sincere. Whether intended as an adjunct to commitments to building an abundance of clean energy and reducing emissions it will be used by opponents - and the apathetic - to reduce those ambitions.
2 points
36. Planet internal gravity

Yes, that's reasonable. I believe it would be an extension of Newton's original formulation for thin shells, but it's simple enough. You can think of any spherically symmetric planet as an onion, with lots of concentric shells. 🙂
2 points
37. Consciousness Always Exists

Pretty much all research into the neurological basis of consciousness finds it to be emergent rather than fundamental. One molecule of water isn't wet. A billion are, at sea level between 0 and 100 C. As for theories, those are generated by minds. It doesn't mean what the theory is about is also generated by minds.
2 points
38. GPS timing (from Time and relativity (split from The Nature of Time))

I’ve seen this claim before, but it’s actually erroneous. It’s true that if the GPS clocks were not adjusted they would accumulate a time difference of ~38 microseconds a day as compared to ground clocks (and ct would be around 10 km), but this would not show up as a positioning error in GPS, since the GPS clocks nominally run at the same rate, and the trilateration uses timing differences between signals from the GPS clocks. These clocks would random walk away from each other, and accumulate differences from orbital variations, if not synched up. But this would be on the scale of nanoseconds, not microseconds, per day. One of the reasons the clocks are adjusted is so that you can do clock corrections from the ground station, which uses time from the USNO master clock. If you didn’t do that, you would be forced to have clocks synchronize within the constellation (whose clocks are less stable than the master clock) which would be less efficient and less precise, so you’d potentially end up with a larger positioning error. But measured in meters, not kilometers
2 points
39. coral growth vessels

My tank is larger than your tank.
2 points

2 points
41. Can we create Micro Climate Craters on Mars by deflecting Comets? Need Peer Review

According to my calculations Mars having a Scale Height of 11.1km means that we are only 30km away from reaching 0.7 bars of air pressure from the Northern Basin or Hellas Planitia. Can we deflect a comet or more to the same spot on such an elevation on Mars to excavate 30km? Then the water from the comet can produce a liquid water lake for us since it will be within the Armstrong Limit now and we can introduce algae and plant life in cheap greenhouses to slowly terraform Mars as a micro climate via photosynthesis to convert the CO2 to O2 slowly. The comet the size of Hailey’s would also contribute 1% to the Martian atmosphere with gas. While negilgible on it’s own if this becomes a regular occurance, 100 comet strikes will double the Martian atmospheric pressure and air density. This also means the future Micro Climate Craters can gradually be shallower and shallower eventually only needing to be 15km deep in the future. Could we deflect enough comets to excavate 30km from the Northern Basin where it’s-7km from the datum? Or maybe from Hellas Planitia? We could settle at the bottom of such a cavity and use airships for transportation without risk of explosion in the CO2 atmosphere, we could also live without the need of airlocks at our doors to maintain an air pressure bubble within the Armstrong Limit and we will have supply of drinking soda water and water for rocket fuel via electrolysis producing both breathable oxygen gas as well as hydrogen for rocket fuel and airships. We wont need full pressure space suits just flimsy stratapause type ones. I have attached concept diagrams/illustrations with my numbers, please check them out but ignore the drill hole and anything related to drilling because I found out that Tzar bombs alone won't dent Mars enough to excavate the depths required. But Comets would because they will have 1.2 million Tzar bombs worth of kinetic energy. Please share your thoughts with me!
2 points
42. Electron shells

Electrons in atoms can be thought of as standing waves corresponding to resonant frequencies, ie. a series of harmonics. In fact the shapes of atomic orbitals are spherical harmonics, akin to the modes of vibration of a rubber ball if you hit it and look at how it vibrates with a strobe light. Each electron occupies a different quantum state. It has to, as electrons are fermions. "Shells" are simply groupings of related, but different states that are possible for an electron to occupy in an atom. Each shell comprises all the states that have the same principal quantum number, n. But n is only one of 4 quantum numbers needed to specify individual possible states. They others are: - l, which denotes the angular momentum and determines which subshell the electron is in (i.e. s, p, d, f etc), - m(l), which determines which member of the sets of s, p,d, f orbitals the electron is in (e.g p(z), d(x²-y²), etc), - and finally m(s) which determines the spin orientation within that orbital. So one can have a maximum of 2 electrons per orbital, one with spin orientation "up" and the other "down". In chemistry, this accounts for the pattern of the Periodic Table of the elements, each row corresponding to the highest occupied principal shell that is occupied, 1st row n=1 2nd row n=2 etc. (cf. Aufbau Principle.)
2 points
43. What would be the most important thing than humans should try to achieve in priority in your opinion ?

Historically, the same mindset was applied to homosexuality. Nobody is identifying as a dog, but you raise a valid point that people’s rights shouldn’t be limited when/if they do. “Gay marriage?!? What’s next… letting people marry their dog!!” Ahh… memories.
2 points
44. 'Six Strikes & You Are Out ?'

The job has some real power. Appointing members to committees for example.
2 points
45. What would be the most important thing than humans should try to achieve in priority in your opinion ?

You keep reflexively referring to them as "male identifying as female." They're just "female." Why is this such a struggle for you? You misspelled female again Unless your concern extends to female teachers as well, then it's unclear why this is a problem. Why can we not just all agree as I suggested earlier that rules for teachers in children changing areas should be applied consistently regardless of gender, whether that gender is cis or otherwise? You'll get no disagreement from me here. I think pretty much everyone here agrees with this. However, you seem to be arguing that your daughter is at some extra risk because some teachers are transgendered. That doesn't make sense unless you fear transgendered people, and you don't strike me as the fearful type... not over pretend and invented enemies, anyway.
2 points
46. 'Six Strikes & You Are Out ?'

Rumor has it that they’re going to nominate Mike Lindell to be Myspeaker.
2 points
47. dark matter question

Genady has a point. Gravity causes planets,etc. to form because regular matter interacts electromagnetically. Collisions, friction etc. is a result of this electromagnetic interaction. A secondary result of this interaction is the production of electromagnetic radiation. The production of this comes at the expense of kinetic energy from the matter involved. Two particles collide, emit some EMR and separate, but at a slower speed than they met at. This happens enough and a clump of matter of matter forms. DM does not interact electromagnetically, not only does that mean it doesn't "collide" like regular matter, but it doesn't have the same mechanisim to shed KE. A DM particle can approach a planet, pass right through it, and fly off with the same speed it started with. There's is nothing to hold it in the vicinity. Having said that, There are ways for DM to clump. Gravitational interactions can cause such distributions. But compared to electromagnetic interaction, they are very,very, very, weak, and produce results much slower. The Universe just hasn't been around long enough for small compact collections of DM to form, Just much, much larger and diffuse collections like galactic halos.
2 points
48. Interpretations of QM

I appreciated the nod to a realist interpretation. And dig at string theory. I think my earlier comment on cowering from probabilistic theories was confused by some - @Mordred was one - as me not seeing the uses of probability in physics. Well of course I do. What I should have said was I'm leery of acausal theories (aka nondeterministic), which seem to skirt thorny ontological problems and just tell you like a stern schoolmarm that it's all stochastic. Here's a lump of twenty trillion thorium-234 atoms. Some of them will soon beta decay to protactinium-234. Some of them won't. Let's give each thorium atom in the lump an address. And name. At 221-B, there is Sherlock. At 10, is Boris. Either could, randomly, decay. As it happened, Boris decayed first, before Sherlock. At a macro scale, such an event seems to have a cause. We have an ontology of macro scale Borises, and can understand why they decay so easily. But the thorium atoms all seem identical. All intuitions seem wrong. Ontology can help. Maybe.
2 points
49. The Official JOKES SECTION :)

The price of funerals has gone up a lot lately, adding to the general rise in the cost of living.
2 points
50. Greening a desert. Would this be worth a try?

I've got some background in environmental sciences, and the very first thing you need to "green" anything is water retention and stable substrate. Shifting ground and water evaporation will greatly impede and plants trying to grow in an area. An oasis is a place where there is a large collection of protected water thanks to local geological structures. They're usually natural springs or wells from the water table below the desert sand. Plants require a place to root and annually reliable soil. Simply watering the sand isn't going to be enough. Wind erosion is also a major hurdle for plants. Some can withstand flat, open lands with full sun and arid temperatures, but not the kind that will create a forest. The Dust Bowl in the United States was a good example of this. Rich soil is created by lots of organic matter. The best way to create more forest against a desert is to start on the edge and keep building ecologically sustainable areas inwards. That might mean digging wells or creating large ponds and lakes to hold what little rainfall there may be. I know there are people that use something called 'swales' to do this. https://naturalbuildingblog.com/greening-us-deserts-80-year-old-swales-near-tucson-arizona/ If you want to create a lasting forest, it has to be able to survive after the initial human intervention. There are a lot of other factors, too, such as which plants to grow in that area (you want hardy, native, 'foundation' species to begin), but you definitely want to work with nature rather than against it.
2 points
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