Ken Fabian

Not sure what is meant by "the energy crisis". I thought first you meant the climate change challenge of replacing dirty energy with clean but suspect it may be the short term shocks from Russia's Ukraine invasion you are referring to. I have no doubt that European nations are quantifying near term available energy resources and requirements in mathematical terms - something nations tend to do anyway, just with more urgency at the moment. But whilst finding the optimum based on those factors may be possible there is politics and balancing various interests to complicate things. EG - clearly it is given that German Greens will oppose extending the lives of nuclear plants - but Germans apart from Greens have misgivings too or the agreement to close them would not have happened. Some of those are more about the poor cost effectiveness of keeping them going given they are expensive and they need a lot of work. Other Germans don't care about climate or nuclear and want returns on their brown coal and gas investments. A study showing other options would be better than nuclear will not be welcomed and would face opposition, just as studies showing doing upgrades to existing nuclear plants would help will face opposition. Given we've had more than 3 decades of consistent science based studies showing we need to get out of fossil fuels the growth of their use was (and is) widely supported by the same governments that commissioned and funded those studies - it is clear that doing studies isn't the biggest problem.

These "scientists" probably had a lot of fun speculating - but it was speculation plus imagination, not a science based prediction. Even basing future changes on trends within our species looks problematic, as would proposing there is some ideal form and seeking to define it. The linked articles were not very impressive - and that goes for the source material that got quoted in them. Like - Perhaps that is true based on an average across the whole population, but that can be from a: people everywhere are all getting larger foreheads or b: the proportion of people with the genes for larger foreheads has grown in proportion to people who's foreheads are smaller or c; this is a consequence of change to living conditions, not genetics. a: (if it even could happen) would be evolution across the species but b: would be existing variation within the species. Until and unless some selection process eliminates the ones with smaller forehead our species is one that encompasses larger and smaller foreheads. The conditions that have caused the numbers of people with large foreheads to grow may be shortlived - and that period is so short in evolutionary terms and the changes of the conditions people live in so great that it needs to be established that the difference is genetic change. I expect that, so long as our advanced industrial civilisation doesn't implode, we will have that capability within the current century. If not genetic then surgical and other modification can deliver desired appearances - but without passing them on. No guarantee that everyone would take either option up. 60,000 seems like a number pulled out of the air (or perhaps some orifice). The supposed idealised beautiful human face isn't a universal thing. This is pure nonsense IMO. Contradictory as well - low light but high UV? IF humans colonise space they will make their own environment, including lighting. i don't expect terraforming to be able to make outdoors possible for space colonies. Light intensity may well be reduced compared to direct tropical sunlight or what is used in grow tunnels but will be close to how we do indoor lighting - because that's how we like indoor lighting. Eye size seems more likely to be changed on purpose, because people think they look better. Since no-one knows how different or can know that people of the future will be deeply unhappy about their appearance and there is nothing to do about it if we did know - there is no incentive to intervene.

But it will be inefficient and likely will impact how quickly food goes bad. Food in the door and at the front is likely to be more affected. The fridge will work harder re-cooling itself, with greater use of electricity than a light - with no real difference by changing the thermostat setting, except to make it go colder than before, once the door is closed. Even a low power night light left on might be a better alternative.

Why would good and evil not be subject to cause and effect? Isn't the point about doing good or doing evil all about consequences, ie the effects? Also, is "the law of the jungle?" actually a thing? It isn't a term used much by biologists. Lots of animals are social and engage in co-operative behaviors. Cooperation and Competition both have their place. Even the fiercest warriors can be thankful that they can go home to a community that will care for them when injured or in their old age.

Members here are basing that on decades of scientific studies, that have been built in turn on a foundation of ever improving understanding of fundamental physics and chemistry and of understanding of climate processes. That agreement is not simply a case of our opinions being a majority here but of the majority here being familiar with what those studies have been saying.

A lot of the health issues around radioactive materials are actually chemical in nature, by being chemically toxic and biochemically carcinogenic. Eg, Strontium 90 when ingested will be used in place of calcium in cells and tissues, but then the Strontium undergoes radioactive decay, breaking apart the molecules they were part of (which may become toxic in turn) and becoming Yttrium 90 and then Zirconium 90 whilst releasing alpha, beta and gamma radiation, which induces further unwanted and potentially harmful biochemical reactions in surrounding tissue. Re the Thermal History of Earth there is still a lot of uncertainty but the fundamental processes appear understood. Like heat from compression being ultimately attributable to the formation of the Earth - the energy came with the materials that coalesced to make Earth. And whilst we may not perceive rock as being a good insulator it is in fact a very good one when it is hundreds of kilometres thick, so much of that heat has still not managed to get out.

I don't think it is so simple or so dark. The shaman/priests weren't usually the chiefs and whilst both might have status and power and interests in common each would be a check on the other. Lore and law often bound even the behavior of priests and chiefs. Our prehistoric ancestors were not simple brutes even if - as now - they were capable of brutality. I expect there were sincere and sometimes desperate efforts to call on spirits and gods for the good of the tribe as well as chiefs and dynasties that sought to lead well, with the support of their community. It wasn't always winner take all. And their communities were not powerless; bad things could happen to chiefs and priests that let everyone down.

The flooding in Lismore exceeded the previous highest flood level by so much that many people who believed themselves safe and prepared found they were not. Downtown Lismore (behind levees) expected the ground floors to be inundated but the next level up to be safe - so they shifted valuable goods as well as themselves up to there. And got badly caught out. Being up on stilts was not enough - and gave many people a false sense of security. Between raised sea surface temperatures and raised air temperatures the severity of rainfall events is raised... when conditions suit rainfall. When ENSO is in la Nina phase Eastern Australia gets more air flow from the Pacific Ocean over land - in combination with that warming it isn't difficult to see why this would increase rainfall intensity. During El Nino phase the prevailing air flow is more often from Central Australia towards the coast - and whilst warmer air can take up more moisture, it also takes more water vapor content to reach the saturation needed to induce rain; it isn't difficult to see how that would lead to reduced rainfall. Like sea level rise for The Netherlands with the existing propensity for inundation, being "a land of droughts and flooding rains" doesn't make greater extremes of droughts and floods for Australia less concerning. Quite the opposite. Like with "but the climate is always changing" the susceptibility of the global climate system to natural change makes it more susceptible to change and to reach new extremes from raised GHG's; it would take climate that doesn't change for it to not matter. There isn't much doubt the current Australian government has protecting the fossil fuel industry from emissions reductions ambitions as higher priority than reducing emissions. The Minister for Energy and Emissions Reductions has been tireless on that front. For non-Australians the Australian Prime Minister is bottom right, with the lump of coal he once brought to parliament to attempt to ridicule those who have been calling for Australia phasing down coal exploitation - "don't be afraid" -

You are right. Some blanks are not going to be as significant as others. Some people will be less fearful of the unknown or not need explanations for the inexplicable. But it can be socially disruptive to have competing beliefs or for dangerous beliefs to spread unchecked. I like to think I am rational but I still have the emotive responses to the strange and unexpected. Superstitions I learned as a child can still be triggered, even though I dismiss them as irrational. We are susceptible - our powers of imagination can be a vulnerability as well as a powerful tool to provide understanding and predictability.

Yes, people will fill in the blanks with something, right or wrong.

A community that shares language and beliefs and rules of behavior has advantages. I think the human imagination and propensity to dream and fear the unknown combine to make having shared beliefs, even wrong ones, better than having none. The need for sharing beliefs came long before it was clear what was rational and what was not. The power to evoke strong emotions does make humans vulnerable to manipulation - but makes it possible for leaders to unite and inspire them to a great task or a Cause. The power of unified belief to aim people in the same direction have made societies strong. Having unified beliefs that are all evidence based and rational ought to make societies stronger but I don't think anyone's ever actually tried it. I'm not sure humans are even capable of agreeing on what is evidence based or what is rational. If you come to that question with beliefs already in place they probably seem evidence based and rational.

Insecticide impregnated mosquito nets work well where humans are the attractant. Impaling is not an effective way to kill mosquitos. A lot of thinking and a lot of work has already gone into mosquito control; better to review what has already been done before attempting new and unusual methods. Mesh works quite well to keep mosquitos out of water tanks but it requires good design, construction and ongoing maintenance (cleaning mostly) as well. We usually have a mosquito proof strainer set into the top of water tanks, but there can be gaps if not screwed down. But leaving them not screwed down makes lifting them out and emptying accumulating leaf and other debri easier, so they often aren't. Also the overflow outlets have mosquito mesh - but can get clogged, so the water level can sometimes rise above the level of the (sunken) strainer. Mosquito eggs laid in that water can be small enough to pass through - which isn't a problem so long as there is no way for an emerging adult to get out.

Well, that is a surmise, but one that seems sound. People like Nina Jablonski who have made skin evolution their area of of study think dark hair over light skin came before (misnamed) hairlessness - that being the usual pattern within related apes. She does thinks dark skin probably developed as a response to raised UV exposure in prior furless hominids, before homo sapiens, ie the earliest homo sapiens were dark skinned. In reality no-one knows. But yes, the variations of skin colour we see in modern humans came after the earliest homo sapiens, as did variations of adult hairiness. The absence of variation of juvenile hairiness across our species was probably present in the precursor species and (I think) probably preceded us, but the variations in adults is a secondary sexual trait that came after. No it doesn't make sense. The genes and traits every member of a species share go back to common ancestors. The genes and traits we don't all share - the variations that make different groups different - will have developed later. The earliest homo sapiens didn't have (all) the genes of every "nationality", mutation will have introduced new ones, the ones that make them different to their ancestors. Yes there are genes they had that everyone has. Those are for the traits we share in common.

I think we are arguing over terminology. The first post claimed it is an example of an Elastic Fluid, but I'm not convinced that it is what the phenomena described is. That may have led me astray. "Elastic fluid" seems to refer to compressability - Elastic waves - Surface waves that appear in a brandy bowl may indeed be examples of "elastic waves" in a fluid; something I wasn't aware of - I stand corrected. I had been thinking there was flow of matter involved - but I may have been misunderstanding "flows", ie where a container wall moves back and forth and displaces water without compressing it. It will involve wave propagation by compression and release (elastic fluid) but most of what we see in that bowl will be water physically moving rather than being compressed and uncompressed. Introducing the topic with reference to elastic waves rather than elastic fluids may have avoided confusion.

@SuperSlim -As long as you use the term "elastic" so broadly and wrongly you will mistake phenomena that have nothing to do with elasticity for phenomena that do.

The combination of container and gravity makes the shape of that water in it's hypothetical undisturbed resting state. Other forces make waves and motions, like vibrating the container to create standing waves. Friction damps those motions. It isn't elasticity - that is a misleading misnaming of why, when external forces cease it reverts back over time to it's resting state.

In Singapore it is illegal, because of mosquitos and malaria. Here in Australia rainwater is commonly collected and used for both household and garden use and usually tanks have mesh to discourage mosquitos (but unless well maintained, not always preventing their larvae getting in). Most of our own personal household water supply is water collected from our roofs, but we are rural, outside any municipal water supplies. Some places there can be reasons to avoid them - eg having big overhanging trees with bird and fruit bat populations can make the water unsafe to drink. There were widespread restrictions on household tanks in urban areas in the past, in part to support the viability of municipal water supply systems. Roof and other rainwater runoff is usually directed to "stormwater" drains that (usually) feed directly into creeks and rivers. Increasingly with some "pits" to catch rubbish. Oil, rubber and other contaminants etc off roads isn't separated. Of course when there are floods waste of all kinds ends up in floodwater. Rivers are most often the source of irrigation water for farms, without any specific water collection or diversion; specific collection tends to be on-farm (earth dams) or part of larger irrigation schemes, based around existing rivers and catchments and dams. Economics is probably the biggest impediment. Water isn't often diverted large distances unless part of larger schemes, like the Snowy River hydroelectric diversion of coastal flowing water inland, in combination with the Murrumbidgee Irrigation Scheme built around those flows. Even now it is unclear whether such schemes (minus the electricity) were ever cost effective but psychologically they were and are reassuring to have in a nation with climate that swings from extremely dry to wet and back again; political careers have been bolstered by vocal support of grand schemes that have been repeatedly shown to be unrealistic and economically wasteful. Agriculture is usually where it is because it has the soils, the climate, the rainfall, the rivers so additional water resources like urban rainwater runoff, that need a lot of investment and infrastructure to be useful are rarely that significant. Unrealistic and economically wasteful is why catching and diverting urban stormwater to rural irrigation isn't done.

Neither the disturbing force nor the dampening requires or is a result of gravity, but I would expect the experiment to play out very differently without it.

Gravity holds it in the container but wouldn't make motions within the water stop. I would expect friction within the water will be what dampens any motions. Plus some dampening from internal friction within the container itself, which would have to flex to pass vibrations to the water and would be flexed in turn by water motions.

This field that affects high velocity electrons appears to be entirely natural and doesn't prevent spacecraft or people from leaving Earth. I have formed my own opinion that this discovery by a team at University of Colorado Boulder is not evidence of aliens having turned Earth into a prison. That claim is nonsense.

Two objects tethered together will be intrinsically stable rotating around a shared axis. More than two will be unstable. Not impossible to have more but active control of some sort would be essential. Rigid structures would defeat the purpose of reducing structural requirements. The engineering challenges for building a rotating structure for pseudo-gravity on - or perhaps in - Mars or Moon (or an asteroid) probably aren't that much greater than building in space, but engineering the transport system to commute between orbit and Mars or Moon will greatly increase the overall difficulties. For asteroids that part would be easier but building inside an asteroid would give plenty of radiation shielding, which a station would have to carry as mass. Asteroids at least offer the potential for trade in bulk physical commodities, which Mars and Moon do not. But to get across the line and be economically viable I expect any attempts to mine asteroids will be based around remote robotics and will ruthless in eliminating any unnecessary dependence on astronauts. The economics are not incidental - for grand space dreams like permanent, independent human habitation commercial profitability based on sound business plans look essential to me.

I suspect the issue is the use of the word "elastic" is a bit elastic. Like The Greenhouse Effect doesn't actually work like a greenhouse, compression and release of fluids - Bulk Modulus Elasticity - isn't the same as "elastic" as used with respect to solids. Enough similarity that borrowing "elastic" seemed appropriate to whoever named it despite being very different phenomena.

Thanks for that. And scienceforums.net isn't Congress. Cultsmash can feel vindicated about being oppressed whilst remaining free to express his/her opinions in a variety of ways without restriction, but somewhere else - sounds like win-win to me.

@beecee - be aware I did some edits while you were typing your comment - I changed some of what you quoted. Which hasn't really changed the meaning of either comment.

Some interesting and worthwhile comments - from pretty much everyone except cultsmash, who seems to want to pre-emptively play the victim card despite not having been prevented from expressing his views here. I think lots of people want limits on freedom of speech for a variety of reasons - often to limit hateful and violence provoking speech or malicious falsehoods generally, which I agree with. But many also may support limiting access to opposing opinions for partisan purposes, which I don't agree with... so long as it isn't hateful, violence provoking and promoting malicious falsehoods. Freedom to tell the truth is not equivalent to freedom to promote falsehoods. There are also all those nations and communities where criticism of governments and institutions and officials and policies are indeed illegal - and yet those laws can still enjoy wide public support, perhaps influenced by social conventions and misinformation and not entirely "freely" - but in the absence of credible alternative government, they may be perceiving harms to the govenment's reputation as hurting them. Here in Australia we get "culture war" arguments that rosie glasses views of history should be defended for the sake of national identity and pride and "black armband" views that might induce shame or regret (like teaching about brutalization and massacres of aboriginal people in schools) should be left out - much like the US and learning about historic slavery and current institutional inequality via "Critical Race Theory". As for US constitutional "freedom of the press" aka "freedom of expression" - it appears to me (from outside) to be about the freedom of "press" owners (nowadays, media owners) to promote whatever political causes they like, without any direct requirement for what they say to be true. The US still has civil law remedies for slander - for falsehoods that cause harm to reputations and incomes but those are only for those who can afford to pursue them, after the lies have done the rounds and done them harm. I suppose some jurisdictions do include criminal laws against slander - limiting the right of citizens to spread lies about people - but I am not familiar with any.