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  1. 8 points
    So if I change the charge of one plate, somebody can measure an instantaneous change at the other plate. Wouldn't that be a violation of special relativity? @Menan You show that you do not understand entanglement. Let's go one step at a time. First a classical example. I have a bag of balls, they are all red or green. Without looking I pick two balls, and I put them in separate boxes. I keep one, and send the other far away. Then I open my box, and see it is a green ball. What can I conclude about the colour of the ball in the remote box? Right, nothing. And why? Because there was nothing special with my picks. It could have been two reds, two greens, or one red and green. Now I pick, looking of course, one red and one green, and put them in two separate boxes. So what I did here is 'entangle' the balls. Now I shuffle the two boxes, so that I do not know which one is which. If I open one, and see that it is red, I immediately know that the ball in the other box is green. And of course, this is independent on the distance. If I send the second box lightyears away, and only then open my box, I still know immediately what some alien sees when he opens his box. I know it because the observations are correlated. And the correlation already happened at the moment of my picks. That is the moment of entanglement. It is not when the boxes are opened. Now in quantum physics, there are processes where two particles pop out, which have e.g in one aspect always opposite values. Say the direction of spin. So if I measure the spin e.g. in a vertical direction, say it is 'up', then I immediately know that the other one will measure spin 'down', when also measured in the vertical direction. But as with the balls, the 'moment of entanglement' is when these particles popped into existence. But in quantum physics a few things are different: first, it is impossible to say which particle has which spin without measuring (it is as if I created the green and red balls, including their boxes, without knowing which ball is in which box). But as the two particles are entangled, if I measure both, the measurements will always be correlated. And there is nothing special with correlation: if I send one particle far away, and then measure my particle in the vertical direction, and the alien measures his particle in the same direction, I will always know what he measures: the opposite of my measurement. The 'spooky' aspect comes in when we do not know from each other in which direction we measure the spin. It can be vertical, horizontal, 30o, 45o, 55.3977o. What we find is that the correlation is stronger than one would expect if we would assume that the particles already had a definite spin from the beginning. But it still is correlation, not causation. As with the red and green balls, there is no direct causal relationship between my and the alien's observation. The causal relationship goes back to the moment of 'entanglement'. Everything afterwards is just correlation, and therefore cannot be used to transfer information. And because there is no causal relationship between my measurement of the spin of my particle, and the alien's measurement, I cannot use entanglement for sending information. And all this is very well understood by all quantum physicists, and is no secret at all.
  2. 6 points
    Implicit here is a false suggestion of equivalence. That’s not the case. If a kid walks down the hallway in school and gets punched in the face and has his lunch money stolen, is it his fault for carrying lunch money or walking freely down a public hallway? No, of course not, but if you think “both sides” need to compromise here then that’s precisely what you’re saying... that the kid is equally guilty as the bully. Trump last year said send a bill to my desk and I’ll sign it. Republicans were in control so drafted their version. Democrats agreed to vote for it and provide billions of dollars for this wall last year, and the compromise was that dreamers would get status. Trump backed out. He moved the goalposts. He said I want more. Funding ran out in December and Democrats said, fine... we’ll sign the republican bill yet again... we’ll compromise... but want money allocated to smarter enforcement options. A wall is not smart, and even countless republicans across the nation and some on Fox News itself agree. Trump said no. Eff you, a wall or nothing. Democrats said, Republicans still control all 3 branches of government. Since they’re in control, they need to get their president onboard. They couldn’t. President had a tantrum. Paper tiger in the Oval Office. Said he wants a shutdown. Shutdown began. Democrats took control of the house in January and on Day 1 passed a bill to reopen the government. Senate leader McConnell would not even bring it to the floor. Democrats later said they’d give more money for border protection, just not a wall. They compromised. President still refused. Wall or nothing. Eff the workers. Democrats passed multiple other bills to reopen parts of the government and agreed to negotiate terms on border security. They AGAIN voted for the previously passed republican funding bill from December. McConnel AGAIN wouldn’t bring it to the floor. Today Democrat senators continued to pressure McConnell to bring the bills up for a vote. He refused. He said it was pointless because the president won’t sign. Democratic Senators reminded him that they had the votes to override a presidential veto... that they are a co-equal branch of government and need to act like it. McConnell left. He just walked off the floor. Still no vote. Democrats will again pass a bill tomorrow to reopen the government. The bill will be the one drafted and previously agreed to by republicans. I agree there’s a lack of compromise here, but to say it’s equal across the aisle is absurd. The bully is trying to steal the lunch money. The other side has already offered to share their sandwich with him and are not at fault merely for having lunch money in their pocket.
  3. 6 points
    Right, he is saying that the speed of light in both directions is the same with respect to any inertial frame as measured from that frame. So in the following example we have two observers. One standing along the tracks and the other traveling along the tracks in a railway car. Two flashes are emitted from two points along the tracks that are equal distance from the track observer. the light from these flashes arrive at the midpoint observer at the same moment as the railway observer is passing him. Thus both observers detect the light from the flashes at the same time. Like this: For the midpoint observer ( or anyone at rest with respect to the tracks) these flashes were emitted simultaneously, as shown by the expanding circles: However, for the railway car observer, events have to occur differently. He still detects the light from both flashes simultaneously, and they arrive when he is adjacent to the track observer. But unlike the track observer he has not remained halfway between the emission points the entire time. He is not an equal distance from the emission points when either of the flashes was emitted. But he must also measure the speed of light for each of the flashes as being the same relative to himself. But since the distances each of these flashes travel relative to him are not the same, in order for the light of the flashes to reach him simultaneously, they must have left at different times. And the sequence of the events for him occur like this: For the track observer, the flashes are emitted simultaneously, but for the railway observer they are not. This is the relativity of simultaneity: Events that are simultaneous in one inertial frame are not so according to another which in relative motion with respect to the first frame.
  4. 6 points
    I am pleased to now add CharonY and Strange to the list of gullible fools wonderful people willing to sacrifice their time for the greater good here at SFN. Congratulations!
  5. 5 points
    Hello everyone! It has been a while since I was active in the forum. Sure, I post a song here and there, but I just can't participate like I used to. I'm still having problems with my left hip even though I had a hip replacement back in April, 2017. Since then, I lost my job and medical insurance because I simply can't sit and write code for hours on end due to the extreme pain in my left hip. I lost my job as a software engineer in the middle of being treated by my doctor and they want a $500 deposit to continue treating me. Unfortunately, I don't have any income, I'm unable to work, and I've blown through my savings on living expenses and doctor bills. Most likely, I will need a revision done on my hip replacement to fix whatever is wrong so that I can go back to work and be a productive member of society. So, I'm reaching out to the community and asking for your help! The following link is to my GoFundMe campaign. I've attached photos of how my surgeries went so you will understand how much pain I'm actually experiencing. It's ok if you can't donate. You can help me out tremendously just by sharing this link! Every little bit helps!!! https://www.gofundme.com/clevelandraymond Thank you all so much! I truly appreciate anything you can do. Not only does your efforts mean the world to me, but also to my family as well.
  6. 5 points
    We're working on it. http://indexsmart.mirasmart.com/IFCS2018/PDFfiles/IFCS2018-000128.pdf https://www.osapublishing.org/josab/abstract.cfm?uri=josab-35-7-1557
  7. 5 points
    Accusations of deliberate, widespread bias and falsification of results, across every major institution (in several different nations) doing climate science and climate modelling really does require evidence. Evidence of which, if this misconduct was really going on, would leave a much clearer trail than a couple of questionable phrases in one email exchange. There is no such evidence, just accusations or it would have come to light a long time ago. Does anyone really think successive governments across the developed world, many with demonstrated hostility to climate science's reports and studies, could not uncover that extent of deliberate bias and collusion? Or that level of incompetence not be noticed within long running non-secret institutions where high standards - with everything on the record - are essential to everything they do? The claims of bias and incompetence are all accusation and no evidence. We have agencies that can pick out guarded exchanges between anonymous terrorist conspirators but they can't catch out hundreds (thousands?) of published working scientists conspiring within and between legitimate government agencies? They haven't exposed this alleged conspiracy of incompetent science and world subjugation because it doesn't exist. Making casual accusations against ordinary people doing their job (better than some people like) is, itself, a serious kind of wrongdoing (slander), besides being very insulting to people who, so far as evidence goes, have been doing their jobs with all the appropriate care and attention and honesty. All that professional effort to work out how our climate system really works, only to be casually accused of being everything from colluding in incompetence to engaging in a global conspiracy! What upsets me almost more than anything else, is that climate scientists have given us an extraordinary gift in the forewarning and foresight they have given. The window of time to transform the way we do energy has been precious beyond price; that we have been squandering it is not the fault of climate scientists failing to communicate. The persistent counter-messaging by opponents and obstructors is indicative of a far more insidious conspiracy of biased incompetence than even their made up version of conspiratorial climate scientists and green-socialist-globalists. In the face of that kind of politicking, and given the seriousness of the climate problem it is climate scientist who do not resort to advocacy that I find questionable. Mistermack - I think you are too gullible and that you have been gulled. I don't expect you to believe anything from me even if you did give it due consideration. Or from Al Gore or from Greenpeace or whoever; however, I do think you should consider taking the Royal Society and National Academy of Sciences, the NOAA, NSIDC, NASA, CSIRO, Hadley CRU and so on, seriously.
  8. 4 points
    I don't know who Christopher Hitchens was, but I came across this quotation from him, that would be a good "mission statement" for the forum: Any better suggestions?
  9. 4 points
    Thanks for that. Just received a reply via E-Mail on the Svidzinsky paper thus..... From: Brian Koberlein <brian.koberlein@gmail.com> Date: 1/9/2019 1:09:45 PM Subject: Re: General Relativity and Vector gravity Barry, If your forum member thinks this paper means GR is dead, they are either lying or don’t understand the paper. The paper presents an alternative gravity model known as a “background independent” model. These kinds of models have been studied for decades, usually in the hopes that they might provide some way to quantum theory. Nothing particularly new here. The author of the paper states explicitly that the gravity wave results are consistent with the predictions of GR, and points out that his model is also consistent with the data. He does this because background independent models have been known to disagree with GR in ways we can now prove experimentally. So basically, this is a “this alternative model isn’t dead yet!” He goes on to talk about dark energy as a way to argue that maybe we should look at the model further. Again, this is pretty standard for a speculative theoretical physics paper. It’s what we do. Come up with ideas to see if they work, because someday hopefully one of them will. There are literally thousands of papers like this out there, and none of them have disproved GR so far. In short, the paper doesn’t say GR is wrong. It actually says its right, and this model could also be right. It also doesn’t say black holes don’t exist, but instead claims that black holes wouldn’t have an event horizon. They would have an apparent horizon, which is basically an event horizon (except for really technical differences I won’t go into). The paper in no way makes GR dead, nor does it make the gravitational wave results invalid. Brian :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: On the reply, the claim re BH's that Brian detailed are exactly what I had in mind. I remember the sensationalist headlines a few years ago, re Hawking supposedly claiming BH's did not exist, based on similar quantum detail re the EH. from the previous reply E-Mail....."The paper presents an alternative gravity model known as a “background independent” model. These kinds of models have been studied for decades, usually in the hopes that they might provide some way to quantum theory. Nothing particularly new here". https://en.wikipedia.org/wiki/Background_independence
  10. 4 points
    You’re making a fundamental attribution error. You worked for ONE corporation that had ONE type of culture, and you mistakenly assume ALL corporations behave that way and it’s just how business is done. That’s not the case at all. There is some overlap in needs, but culture matters most in large enterprises and that culture is set by leaders. Those leaders succeed by setting a vision and getting people to collectively strive toward it. Those leaders succeed by being competent, strategic, and not petty. Childish leaders, however, tend to be more like turtles on top of a fence post. You know they didn’t get there by themselves and only reason they’re there is because someone put them there. Vision. Competence. Strategy. An ability to recruit the very best people on to your team. Trump is none of those things. He isn’t visionary. He isn’t competent. He’s not good at developing relationships to accomplish big things. He can’t recruit even mediocre people to his team, let alone the absolute best. He’s had more bankruptcies than I can recall, and the suggestion you’re making is that he is good at business... which IMO is silly. While he is a poor businessman and while he is extremely childish and laughably incompetent, he very much IS extremely good at branding and steering the social conversation. Unfortunately, he’s not selling a visionary future. He’s selling flimflam and graft much like a modern day PT Barnum. He’s the snake oil salesman that rode into western towns and bilked people from their money, just on a bigger more modern scale. So, at the core of your question IMO rests a bigger question... What does it mean to be a GOOD businessman? Does it mean having an ability to successfully rob from the most vulnerable and navigate corrupt systems, or does it mean having the ability to grow something from the ground up, something that enhances the community, and to gain mass support by recruiting people to step up and help execute on and achieve your vision?
  11. 4 points
    Yes, what then? In my opinion they are intimately related. Let's take an example. Imagine a very weak photon source, emitting about one photon every minute. All around it, but at a distance of one light second (=300,000 km) we have photon detectors. Now according to Maxwell (no photons, just waves) every minute a circular wave front expands into space. According to QM however, we only have a 'probability wave', and the photon is detected at only one detector. At the moment of detection, I know immediately that none of the others will detect a photon. So the event 'measuring a photon' and 'not measuring a photon' are entangled. If behind every detector would stand a human observer, one could send a message to all the others when measuring a photon and tell them that at timepoint 5:09h she knew that nobody else had measured a photon, based on the fact that she already had measured it. So the entanglement follows directly from the wave character of the probability distribution. The power of real entanglement experiments (also known as EPR, or Bell experiments) is that we have positive measurements on both sides, not just a lack of a measurement. But they are expressions of the same phenomenon. So, what then? No. We do not need realtime measurements. If two detectors at a great distance of each other are in the same inertial frame they just can make their measurements, notice the exact time of measurement, and then later compare their measurements. There is no faster-than-light communication. See here. The mathematical theory of QM is unambiguous: entanglement must exist. Do not forget, it was theoretically derived before it also was measured. So there is no problem to solve. The only problem is that we, humans, cannot picture this based on our daily concepts.
  12. 4 points
    coffeesippin has finally tested our patience too far and is banned permanently.
  13. 4 points
    Nope. YOU have made specific claims in this thread. I don't believe them. So it is up to YOU to provide evidence for those claims. There is a high-level summary of some of the evidence here: https://royalsociety.org/~/media/Royal_Society_Content/policy/projects/climate-evidence-causes/climate-change-evidence-causes.pdf Note that it is about 30 pages and only touches on some of the types of evidence. So, as I say, providing evidence in a forum post is not practical. This is a report put together by hundreds of experts (*) on the current state of the science and the potential impacts on the USA. I think it is about 1,000 pages in total. So feel free to come back with questions after you have read it: Volume 1 (the science): https://science2017.globalchange.gov Volume 2 (impact assessment): https://nca2018.globalchange.gov And then there is: https://climate.nasa.gov/evidence/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2995507/ https://skepticalscience.com/evidence-for-global-warming-intermediate.htm https://climatechange.insightconferences.com/events-list/evidence-of-climate-changes http://news.bbc.co.uk/1/shared/spl/hi/guides/457000/457037/html/ https://www.ipcc.ch/data/ And so on and so on But perhaps you think that all of these experts from different countries, universities, political beliefs, religions, sciences, etc are all in some massive conspiracy to trick you. If so, this might be more up your street: BBC R4 "A History of Delusions"
  14. 4 points
    The doctor compared my x-rays from the day I had my hip replacement to today and said that the socket has shifted, which may be the reason I'm having so much pain. He is ordering an MRI and another test, but said we can fix this so that I'm no longer hurting once we are certain what the problem is.
  15. 4 points
    ! Moderator Note Daedelus approached us to coordinate this with the Admins and Mods. We've helped out a member in need before, so please feel free to participate (or not). We wish Daedelus the best of luck in funding his treatments. Thanks to everyone for spending your time here, in reasoned dialogue and intellectual honesty. SFN members are fantastic!
  16. 4 points
    ! Moderator Note Menan was banned for breaking the rules, but for this sentence he should be banned from ever touching a computer again. This ignorance is willful.
  17. 4 points
    Yes, there ought to be a rule that you can leave those discussions, and just take part in the ones that interest you.
  18. 4 points
    I may be re-evaluating my 'fit' on this forum ( politics in particular ), but I still read occasionally, and can't stand lack of comprehension ( on both sides ). The confusion arises because Conjurer hasn't bothered to look up the difference between virtual particles and 'random particle pairs'. Virtual particles exist on 'borrowed' energy, in accordance with the Uncertainty Principle. As such, they are not like real particle pairs and when their time is up, they annihilate without resultant photons. Real particle/anti-particle pairs require the emission of photons in accordance with momentum and energy conservation laws on annihilation. When an event horizon removes one of the virtual particles from consideration, the other ( of the pair ) must by necessity, become real. The 'borrowed' energy that created the virtual particles, must still be repaid back to the vacuum, by the mechanism which 'stole' the virtual particle, the Black Hole itself. If you do the energy 'accounting', the BH ends up losing exactly one virtual particle equivalent of mass-energy, and the universe outside the event horizon gains one real particle. That is Hawking Radiation. Notice that there is no link to the Holographic Principle, other than the fact that the entropy of the BH is encoded on the surface of the event horizon, and this entropy is linked to temperature of the BH, and the resultant Hawking Radiation.
  19. 4 points
    I apologize on behalf of Science that Dark Matter is not yet fully understood. By all means, feel free to not treat us seriously until we rectify this egregious situation. You would think that by now we would have everything figured out. Mea culpa, mea culpa, mea maxima culpa.
  20. 3 points
    I especially like the part where you state that being gay is a natural thing, because many species do it in nature. And the extrapolation you make from this, is that it is OK, since it is 'natural'. And I won't argue with that; it doesn't affect me and provides fulfillment in other people's lives. Live and let live ( that is MY justification ). Yet you fail to mention that in nature, all species reproduce as fast as they can, until they outstrip the ability of their environment to supply them ( food, water, predators, etc. ). Then 'nature' steps in and kills off a whole lot o them, until their population can be provided for again. You fail to mention the predator/prey relation that most species have in nature. How compassionate is the predator to the prey ? Sometimes even within the same specie, there is 'warfare' even more terrible than between humans ( at least we have some rules for military engagements ), and sometimes the sick and infirm ( or even the young ) are sacrificed to predators, to save the healthy herd. All of this is 'natural', and done by countless species. So, I don't understand, why aren't you using the same argument that you used for homosexuality, to justify selfish, predatory, self serving behavior . You instead condemn this behavior in humans, even though it is as 'natural' as homosexuality. I think you need a better argument. ( and to speak for yourself )
  21. 3 points
    I had in mind things like carbon pricing that make the externalised costs part of the pricing of various transport choices, not forced vehicle confiscations. I want reasoned and reasonable responses to climate change from governments - preventing unreasonable responses as well as promoting reasonable ones is a legitimate thing ordinary people can do when they vote. Facing up to it - taking the expert advice seriously - should be the barest minimum to expect, not something an irate public has to demand from someone holding high office. Climate change is not about socialist versus capitalist, it is about accountability and responsibility. It is not anti-free enterprise to want accountability and costing of climate externalities.
  22. 3 points
    Interpreting the hidden meaning behind a person's statements is a fool's errand. His comments could have been exactly the same whether he is innocent or guilty. No matter what he says, some will believe him, some will not. Some will think it is thoughtful, some will think he is being aggressive. Some will find him credible, some will not. Discussing whether or not we believe him or what his intentions are may be an enjoyable pastime, but we shouldn't make the mistake of believing that after a long discussion we will be any closer to knowing the truth.
  23. 3 points
    I was quite confident that at some point this discussion is going to derail. Let's be clear about a few things. The current delay at the border is not due to an unexpected surge of applicants. It is the result of a rule set out by the Trump administration, which is currently facing lawsuits. Some points how asylum used to work: If someone tries to enter the US without proper documentation, they are subjected to deportation, unless they claim asylum. If they do, they are entitled to an interview with an asylum officer. If the officer determines credible fear of persecution (which is a defined term and has been further restricted by Jeff Sessions) , they can go ahead to a immigration judge hearing. However, that step can take years and asylum claimants can legally live and work in the US. Even if they are decided not to be eligible for asylum, but the asylum officer decided that they have credible fear of persecution, they can receive a withholding of removal that allows a stay in the US, but has not path to permanent legal status. Many Haitians were granted asylum under the latter category after the earthquake, for example. Note: none of these paths require detention. Detention originally was limited to folks that either have criminal convictions or other wise pose a threat to national security. And before anyone uses the same language as Trump to describe the process, the vast majority of asylum seekers appear to their court hearings. The Trump administration employed new rules to make this process more difficult and creates delays: Going back to detention. Typically, detention was not used in a blanket format. Folks passing the credible fear test were generally scheduled for release. Under Trump, the release rate dropped almost to zero and has faced a lawsuit this year. In other words, all the malaise of horrible detention conditions, and folks trying to enter illegally are the direct consequences of the policies of the current government. This includes the separation of children from their families, which has been reversed. But it is blindingly clear that the situation is not caused by external effects, it is not due to cost. It is part and parcel of a cruel strategy with the sole goal to curb asylum seekers and falls under the same vein as the Muslim ban.What is striking is the mix of indifference and outright cruelty towards those trying to claim asylum, regardless whether they are ultimately eligible or not. In fact the administration is actively working to revoke the Flores settlement, in order to allow for virtually unlimited detention until their status is resolved . And just to make it really clear, there is no material evidence that shows an increased need for detention during the asylum seeking process. The appearance rate of families, especially if they are provided legal counsel is close to 100%. The group most likely not to appear seem to be individual men with no legal counsel. Those are also most likely held in detention when they have no documentation in the first place. And while we are talking about deterrence, even with all the cruelty which should not baked into a process that was borne out of compassion, the actual asylum claims have been increasing. Let's make this part really, really clear. The policies that the administration enacts, specifically with respect to family separations, are targeted at those that usually have the strongest standing for asylum claims: family units with children. Apprehension of family units have been surging, by September 2018 the largest group consisted of family units with 90k total. This is the highest recorded number ever. So yes, the policy is not there to deter folks who may not have a claim. It is there to specifically reduce those who are eligible. And that is why tear gas on moms and kids was just a natural consequence in the progression of those tactics. Make no mistake, the immigration policies as created by the Trump-Bannon-Miller-Sessions strategies have been outlined early on and should not come as a surprise to anyone. It is not about a surge in immigration, cost, logistics or anything connected to that. The numbers clearly show that it is not the case. The policies clearly show that it is not the case, even if folks want to dance around them. It is all about keeping folks out from certain countries (Norway would be fine, though, so no worries) even, or perhaps especially if they have credible fear of persecution. By employing a tactic of making legal entry much, much harder and increasing the persecution of illegal entries, a home-made crisis can be presented to the public in an effort to outright undermine the right for asylum.
  24. 3 points
    The big picture I was referring to was not the logistics you refer to with the rest of your questions, but our overall vision at the border with respect to humanitarianism, professionalism, and optics in the international community. I've also been trying to convey the point that the logistics involved in with implementing an empathetic and professional approach at the border are a relatively minor detail. We already have the skills, experience, and professionalism needed to implement a more empathetic and less confrontational approach. By changing our message from "invasion" and "responding to rocks as if they are guns" to "we'll get to everyone as fast as we can" and "why don't you get a meal and cleaned up while you wait", we decrease the likelihood of violence and soured international relations with minimal effort. Not to mention that it is the decent thing to do. In a similar vein, when protesters visit a site, we expect our officials to try to defuse any potential conflict rather than incite, and we render aid even to those who are breaking the law. I don't know why we would't want officials at the border and in government to also strive for a peaceful and respectful outcome. At the border, for as long as it takes to eat, shower, and rest their tired feet. Are you asking if we stop fights among the migrants, or if we take steps to keep them from illegally entering the US? If so, then yes, we keep it secure. Presumably there is an entry point to go further into the US already. As far as I'm concerned we can just put up a tent in front of it and let people rest and get cleaned up while waiting. I'm not suggesting any changes one way or the other with respect to immigration policy. Only that we act with respect, kindness, and professionalism while we are going about our jobs.
  25. 3 points
    Interesting question. I think it is mostly about choice of words and I can't see it as a big problem - but is running climate models from the conditions current 100 years ago to see how well they "project/predict" climate changes only up to where we have real world data to compare to really prediction? Well, it does get called hindcasting to distinguish it from models that start with near-present known conditions to see what future conditions might be. Hindcasting is done to verify how well the models work given various inputs, such as including the known rise in things like GHG concentrations, solar input and occurrences of volcanic eruptions over the period. Or alternatively without the rising GHG to see how climate might have changed without them. Is it a prediction (or projection) if it only projects from further in the past up to when real world data runs out? I don't think calling it that is completely unreasonable, but it probably deserves clarification. _____________________________________ There are a lot of misunderstandings about climate model projections/predictions and, like claims of reasonable climate concerns being labelled alarmist, a lot of the claims about modelling getting it wrong originate in the counter-messaging by those opposed to climate action. The "pause/hiatus" controversy for example arose from mistaking - often on purpose and ignoring expert objections - the average of many model runs giving an 0.x degrees per year of warming as predicting that every year will be 0.x degrees warmer than the one before. Which is like saying because models of seasonal temperature changes based on Earth's axial tilt say that on average each Spring day will be warmer than the day before - and therefore, because we just had a string of cooler than that average days, the models are wrong and Summer won't be warmer than Spring. And then suggest it could be the start of a new ice age. Each individual model run actually show similar year to year variability that the real world does - ups and downs, pauses and accelerations, within the range of expected variability; that they do so is indicative of how well they work, not how badly. They just don't have those ups and downs in the same place each time. Which is why temperature trends look at averages over enough time that the expected variability doesn't mask underlying longer term changes. That variability from year to year averages out to a very wobbly line if the period averaged over is too short, such as with "The Pause" which showed less warming than the 0.x degrees per year - and large parts of that variability can be attributed to known climate processes. The largest would be ENSO - el Nino Southern Oscillation - which causes year to year temperature changes much larger than the underlying warming trend - take a ten year period and if there are more la Nina years than el Nino then global average temperatures will be lower, despite an underlying warming trend. The other way about and they will be higher and it could look like warming has speeded up - it takes about 20 years or more for averaging for them to see past the global average temperature swings ENSO induces. Climate scientists most often use 30 years to be sure and routinely point out that looking at shorter periods can be very misleading. Of all measures of global warming I think this one most directly shows actual gain of heat by Earth's climate system - and whilst it has year to year variability a much shorter period for averaging is needed to see past it. Ocean Heat Content shows no sign of an early 21st century Pause in warming (and is not explainable as ".. a consequence of growth of a city, and paving over of land.") -