1. Area54

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Showing content with the highest reputation since 10/17/20 in Posts

1. 4 points

Is global average temperature a useful or thermodynamically valid concept?

Emphasis added. How fortunate the climate scientists provide an abundance of other information concerning temeprature variations in the oceans, the land and the atmosphere, locally and regionally, over the short term ( hours and days) to the long term (years, decades, millenia and beyond), relating it to such diverse issues as ocean currents, weather, atmospheric composition, albedo influences, etc. In short, you have erected a strawman upon which you are making a pointless and ill-informed attack.
2. 3 points

Is global average temperature a useful or thermodynamically valid concept?

I find it really hard to get a coherent picture of the opening post. I see three different aspects that trigger different tones of response, some of which are pretty redundant with the replies given already. So maybe I'll just briefly touch all three aspects to show why at least I have problems with getting a clear picture of this thread. First, there is the relatively long explanation about sums or averages not giving the full information about the individual components that contribute to them. That is correct, mathematically trivial and well known to everyone working in any field of complex systems. It is also pretty banal, and applies to pretty much every science or society related number you ever hear in the TV news: the gross-domestic product, the number of Covid-19 infections, salaries in the IT sector, the time that kids spend on social media, ... . Now, admittedly, there are a lot of people who, for different reasons, appear to limit the discussion of a topic essentially to these numbers. So for this aspect of the opening post I am torn between a sarcastic "great work, Sherlock" and an honest "it is great that you are aware that this one number is not the full picture". I think the relative volume of the sub-optimal example pushed a few people towards the former reaction. Second, there is the aspect of the specific role of an average temperature in climate science, or more specifically its role in the climate change debate. For me, this would be a great topic of debate and learning. I worked as a scientist in a somewhat related field for several years, and still my understanding of it is very basic and with a lot of "that's how I imagine it is". I'll not formulate a coherent story for this post, but just throw in a few imho relevant pieces: In the context of the greenhouse gas effect the average temperature is a very sensible, experimentally-measurable observable with some weaknesses (energy stored in the oceans). Climate scientists don't model average temperatures but create sets of future scenarios for the evolution of complex systems. The evaluation of these scenarios cannot be reduced to a single number that tells you how good or bad the scenario is. What you can do is group your scenarios according to some meaningful parameter, see what typical scenario effects are for that parameter, and then have some delegates barter about how bad you want it. Remember: The problem with climate change is not the increase in the mean temperature, but increase in extreme weather conditions, change in habitability on the planet, the self-enforcing mechanism (loss of reflective ice, melting of permafrost, methane emissions from the oceans), and possibly a bit of land loss from rising sea waters. And finally, there is the third aspect of the opening post which really turns me off: The first half of the first sentence and the last sentence. Thanks to them, the post with potential for an interesting discussion comes in a wrapping that says "troll, ignorant or political agenda inside" to anyone with a bit of experience in social media. So despite giving the OP a huge benefit of doubt with the time I put into this post I don't want to leave them without comment: 1) "Climate scientists are concerned with deviations in the average global temperature": No, they are mostly not. Type "climate science" into Google and check out what they do. 2) "Has there been any research in this area [of what is really going on]?": Yes. There is a complete scientific discipline called Climate Science that is concerned with these questions.
3. 3 points

What is the 3rd dimension?

This is quite ridiculous ... If you have a ruler ( a one dimensional line with numbers on it ) all you need is one number to specify any position on it. If you have a sheet of graph paper ( 2 dimensional numbered grid lines ) you need two numbers to specify any position on it. It is a simple mental jump to imagine a height above that sheet of graph paper with the same grid lines. That is the third dimension, and you now need three numbers to specify a location in that space above the sheet of graph paper. And should you want to assign variables to a specified location, you can call them x, y, and z. Dimensions are simply the directions you can move in a given space. Back and forth, side to side, and up down for 3 dimensional space.
4. 3 points

Source of All

Agree. This is absolute Borax! Especially from a mod! ...and I don't want to hear his next spin cycle!
5. 2 points

Why do scientists believe things?

That doesn't mean anything.
6. 2 points

What age do you think we are in?

The age of bumper sticker level analysis.
7. 2 points

Circumventing Newton's third law through Euler Inertial Forces

Not ones that will work. We already looked at the end of the story. Newton wins. The ONLY way to refute an existing (i.e. experimentally tested and mathematically self-consistent) theory is with experimental evidence. Until such time as you build a device that moves on its own, you will not have shown Newtonian physics to be wrong. All you can offer is analysis that is flawed in some way, and all of your efforts have either been to try and hide the flaws, or by baldly asserting that they aren't flaws (which requires an experiment; see above) This is the playbook that we see over and over again. 1. Convince yourself that your idea is right. 2. Analyze your idea with physics 3. Contort the analysis to reach the conclusion you desire 4. If the flaw is obvious, obfuscate by making the example more complex Whereas in reality, if your analysis reaches a conclusion that violates laws of physics, you know you made a mistake someplace. The math is internally consistent, so this just points to a math error.
8. 2 points

Theory of everything

How might it lead to the proof of the existence of a creator?
9. 2 points

Theory of everything

No effects on humanity. One immediate consequence, physicists would better understand black holes.
10. 2 points

discussion and examination of the rational foundations of religion.

That's what I've always told myself.
11. 2 points

discussion and examination of the rational foundations of religion.

That was my complaint to you. I suppose turnabout is fair play. Good for you. The pride might be better justified if your audience agree with you. Thus far, I'm not sure that has been achieved. It was an interesting take on the history of Chrisitianity, but contained nothing discernible, to me, concerning the "rational foundations of religion". I suggest you need to change the title, or the content of your post if you wish them to match. This doesn't parse. Do you want to try again? That's two more sentences that don't parse. (If you are, as you say you are, a university student you ought to be doing a better job of writing grammatically. )Even if the sentences did parse, I suspect they would make little sense, for I think you are using words with definitions of your own. Also note that many members here are not Americans. So your state flag references need a little more background.
12. 2 points

Consecutive values in set theory

I truly have no idea what this refers to. If you want me to understand what you're saying, can you please supply enough context so that I know what "it" refers to? Nothing to do with intelligence. Just subject-specific education and study. I myself am right at the ragged edge of my own competence in the topics we're discussing and usually have to look things up to respond to your questions. It's just a matter of learning the material.
13. 2 points

Source of All

swansont if you want to talk about lye or detergent, open a new thread.
14. 2 points

Do mitochondria really provide a lot of energy?

If you insist in not understanding how the energy is generated, I cannot help you. However, do you realize: a) how much energy can be gained with from glucose using oxidative phosphorylation vs just the anaerobic pathway? b) how just conducting glycolysis is not sustainable and c) why therefore we need mitochondria? (as these all relate more closely to the question in title ?)
15. 2 points

How can scientific knowledge help someone in his daily life?

It depends a lot on what you know and how much you are in the habit of using what you know. People who have a solid grounding in math and science often apply their knowledge without ever consciously thinking "now I will do science." When I go to clean the bathroom and look at the available cleaning products my wife has accumulated I find myself considering the ingredients and their possible chemical interactions. 10 years ago a tall pine in our back yard died and looked like it would fall, but I was just packing for a vacation. So I quickly used the similar triangles method to estimate how tall it was and decided that if it did fall it would be just short enough not to touch our glass back door. Sure enough we got back from the trip and it was down, and the tip was three feet from the door. It's just a automatic sort of thought process for people who are accustomed to applying math and science.
16. 2 points

Cramming

As you go through notes/textbooks write down key points, ideally in a heirarchical bullet point format. Write in your own words, but retaining technical terms. If you know what is on it envisage typical questions you might be asked, write them down and answer them.
17. 1 point

Aliens on 1,000 nearby stars could see us, new study suggests

https://www.livescience.com/aliens-spot-earth-exoplanets.html
18. 1 point

Why do scientists believe things?

That's not the way it works though, is it? You can actually believe something without investing it with "truth" or even "certainty". I can believe there might be a way for consciousness to exist after death, but I don't have to be certain of it to believe in it. It's more of a hope or wishful thought. Or I can study a subject in depth, learn everything there is to know about it, and be almost certain about what I believe about that subject. At a certain point, our wish/hope becomes trust. I think scientists try hard to trust their knowledge before believing in things.
19. 1 point

Circumventing Newton's third law through Euler Inertial Forces

Ok. Some correctly performed application of Newton will do. The tricks you have pulled out of your sleeves so far are not very impressing.
20. 1 point

Trump's Mind Can Be Guessed in Seven Tries. Tops

Cometh the hour, cometh the man.
21. 1 point

What are your thoughts on the Presidential Debate ?

Indeed. Only 37 times in 90 minutes. Someone should give that man a medal for so successfully lowering our expectations! If only he and his cult members realized not getting covid under control was damaging the economy so much more
22. 1 point

What are your thoughts on the Presidential Debate ?

I think the most striking thing of it all was Santorum's after-debate discussion comment in defense of Trump:" First of all, we do not keep kids in cages anymore...". Says pretty much all there is to say regarding the hypocrisy of a pro-life stance, I think.
23. 1 point

Theory of everything

What has Robert Stephenson got to do with it??
24. 1 point

Is Causual and Random the same thing?

Causal: Cause and Effect Questions Designed to determine whether one or more variables causes or affects one or more outcome variables. A random variable is a mathematical function that ""maps""outcomes of random experiments to numbers. It can be thought of as the numeric result of operating a non-deterministic mechanism or performing a non-deterministic experiment to generate a random result.
25. 1 point

Theory of everything

Do you think that if there are (apparently) two choices, both are equally likely?
26. 1 point

Theory of everything

For starters, these forums would be swamped by a whole new tsunami of religious types in denial. Can you summarize?
27. 1 point

Can Anything Be Relative to Empty Space?

It's kind of like you don't realize there is no paradox, and further, it has nothing to do with length contraction in inertial frames. No, YOU haven't. Your attitude and 'far removed from science' ideas have. None of us like talking to a brick wall; take other's comments under consideration, instead of jumping topics all over the place.
28. 1 point

Is global average temperature a useful or thermodynamically valid concept?

You seem to be overly interested in words and moot points. Saying just "thermodynamics" suggests either classical, chemical or equilibrium thermodynamics; all of them based on equilibrium. There's also statistical mechanics, but that's almost never called thermodynamics. And there's non-equilibrium thermodynamics, but that's such a misnomer (it's not about just heat, temperature, and the like) that everybody referring to it always mentions it by the whole name, "non-equilibrium thermodynamics," only to make clear that it's not thermodynamics (T, Q, etc.) Here are all as covered by Wikipedia: https://en.wikipedia.org/wiki/Thermodynamics#Branches_of_thermodynamics https://en.wikipedia.org/wiki/Non-equilibrium_thermodynamics You tell me which one you're referring to. There's also kinetics, but I'm not interested in climbing the tower of Babel. I meant (and I said) regions of phase space. Regions of phase space are not regions of 3-dimensional space. You're confusing both. I mean volumes in the way of, $d^{3n}xd^{3n}p$ IOW, regions in a humongous 3Nx3N-dimensional space. It is in that space of huge dimension where sampling is robust. Macroscopic systems are ergodic, meaning that time averages give you a very good idea of phase-space averages (averages to all momenta and all positions) when systems are at equilibrium or going round and round in cycles. The molecules you describe as going up to the outer reaches of the atmosphere have to go back and recycle, participating in the overall thermal and dynamical processes, and exchanging the energy. That's the key. But all this is quite academic and, if pressed, I wouldn't be too sure of anything, the way you seem to be. Here's a much more intuitive explanation of why sampling in this way works even for chaotic systems: Tim Palmer's lecture at Perimeter Institute Lecture: Climate Change, Chaos, and Inexact Computing 11' 40''-16' 37'' (I copied the link starting at about the time when he explains the point.) I'm not an expert in climate change. @Area54 or @Ken Fabian can probably give much more accurate information and point out my excesses. I just wish to argue with my toolkit. And with my toolkit at hand, the arguments about "global warming" (however much of just a catchphrase that is) make a lot of sense to me.
29. 1 point

Another go at my spacetime interval question from a week or so ago.

It's meters or lightseconds or any distance units, squared. The use of distance units is apparently a convention, see https://physics.stackexchange.com/questions/519707/is-the-unit-for-spacetime-intervals-time-or-space-distance Yes, for a time-like interval, the time component will be greater than the spatial. For time-like (or light-like for that matter) intervals, the ratio of r/t is the constant speed of a particle that moves between the two events. ct/r would be the ratio of the distance that light travels between the two events (along any path that gets it there, like your 200 lightsecond example) to the straight-line spatial distance between the two events, in the given frame. This ratio is frame-dependent, and undefined in frames where r=0. (ct)^2/r^2... I'm not sure of any meaning to that. As squares, the equation of the interval s^2 (a constant) =(ct)^2-r^2 is that of a hyperbola, and relates to the pythagorean theorem.
30. 1 point

31. 1 point

A universal language

You could consider the plaques added to the Pioneer spacecraft, both destined for interstellar space, where they might get intercepted by aliens. They are described in the Wikipedia article. The logic used for them seems a good starting point. In a sense the object is not to develop a language as such, but rather to find the most convenient way of conveying information. Of course, we need to account for the possibility that the aliens we hope to "talk" to are deaf, or blind, and communicate via odours, or body movement, or . . . .
32. 1 point

discussion and examination of the rational foundations of religion.

Yes, but it was a decent first start. For that, surely it deserves some respect. I mean, you have to start from somewhere. Religion was a first attempt to organise our way of thinking about the Universe. Later, we got into Science, which is much better and far more productive. But the earlier religious ideas should not be despised, or so it seems to me.
33. 1 point

Can you really square a second?

After acceleration, you have even worse: https://en.wikipedia.org/wiki/Jerk_(physics)
34. 1 point

discussion and examination of the rational foundations of religion.

Let me know if you find any "rational foundations of Religion".
35. 1 point

hijack from How do we decide who to trust when we aren't experts?

IIRC it was burning/oxidation in metals, not the burning of wood, where mass increase was observed. Right concept, wrong target. Specifically I think it was a detailed analysis of magnesium. (pause) https://en.wikipedia.org/wiki/Phlogiston_theory “Eventually, quantitative experiments revealed problems, including the fact that some metals gained mass when they burned, even though they were supposed to have lost phlogiston. Some[who?] phlogiston proponents explained this by concluding that phlogiston had negative weight; others, such as Louis-Bernard Guyton de Morveau, gave the more conventional argument that it was lighter than air. However, a more detailed analysis based on Archimedes' principle, the densities of magnesium and its combustion product showed that just being lighter than air could not account for the increase in mass”
36. 1 point

U.S. presidential election modelling

If only it was just ignorance. At this point we see full frontal insanity. And I do not mean that in a partisan way. I mean taking what kids post on a trolling board seriously and make it mainstream, kind of of insane. I mean, there are just so many things just over the top (A prophetic internet troll? Satanic child sacrifices?), it is honestly scary that folks think them to be true and effing run for congress.
37. 1 point

Linux - Which files execute the first instructions when calling the sftp or ssh service on port 22?

That's job of personal firewall. When I was using WinXP, in the past, I was using Sygate Personal Firewall. Unfortunately it does not work with any new Windows. During making connection from unknown app, to the Internet, it was asking and blocking connection, showing user dialog, with question whether to make such connection with the all details about it, IP, port, protocol, packet details etc. Packets could be logged, diagnosed, analyzed etc. etc.
38. 1 point

"And I Don't Care What it Is!:Total Sociological Hypocrisy Full Circle in Alabama"

! Moderator Note What a horrible bot.
39. 1 point

Cramming

!seY That way you cover everything from Z(apatos) to A(rea54).
40. 1 point

Source of All

I think ALL is American: https://americanlacrosseleague.com/ Are the sources intelligent? is another question.
41. 1 point

Source of All

This might be a lye.
42. 1 point

michel123456's relativity thread (from Time dilation dependence on direction)

As an uninvolved and largely silent reader, I got a very different impression - that you think you understand relativity, but actually you are just shoehorning specific relativistic phenomena into a Euclidean worldview (not very successfully, I might add). You have not yet understood on a deep enough level that the world simply is not Euclidean, except as an approximation in the low-energy, low-velocity domain. I am also getting the impression that you are not prepared to even entertain the possibility that the world might not in fact be Euclidean. No, thank you. As stated previously, I have no wish to involve myself in this discussion. I am also able to rigorously see on the highest level, using simple linear algebra, that it is mathematically impossible to construct any kind of physical paradoxes within the axioms of SR, so I do not have any need to find errors in specific scenarios, because the very existence of such errors means that the proponent of the scenario has failed to apply the model correctly. It’s like a third grader getting his long division wrong - their getting the wrong answer doesn’t mean that long division isn’t a valid operation; it means they haven’t used it right. Relativity is just the same. And in both cases, it is best to get them to understand the bigger picture before letting them loose on specific problems. This is what I mean by top-down approach. I’m sorry to be so blunt, but you are just wasting your time with all these specific use cases. You need to get out of your Euclidean mindset, or else none of this will ever make any sense to you.
43. 1 point

Why does gravity prevent a TOE?

If gravity is a distortion of space-time and all the other forces are framed by space-time, what separates the frame of reference? Please remember, I am but a simple layman...
44. 1 point

Are liberals or conservatives more likely to be "triggered"?

This is a new question. Not an answer to mine. https://www.washingtonpost.com/news/posteverything/wp/2018/07/16/its-not-wrong-to-compare-trumps-america-to-the-holocaust-heres-why/ Even Jewish scholars are noting the parallels, and the only valid counter argument to using this comparison is that it short circuits the needed conversation when fine people like you can do little more than attack the comparison for lack of 100% precision.
45. 1 point

Creating universes

You won't. It's impossible. Stop worrying yourself. Get help.
46. 1 point

If we were formed from Condensed Matter, how could you explain the distribution of matter in space to form the elements as we know them?

Is this your actual question? How does science explain the distribution of matter in space to form the elements as we know them? Or is condensed matter an important aspect of the question?
47. 1 point

Are liberals or conservatives more likely to be "triggered"?

No. It really isn't. ...and no...that's not in any way supportive of Trump. I honestly think it's (usually) more against their home team/clan/tribe than their actual best interests.
48. 1 point

Freedom of speech - Can we really have it?

There is an article in the NYTimes talking about this topic, specifically the issues with free speech in a time where disinformation is rampant. The viewpoint is obviously US-centric, focusing on the first amendment. However, it also contrasts it is with European system. A pretty good read. https://www.nytimes.com/2020/10/13/magazine/free-speech.html
49. 1 point

Should Boxing be Banned ?

Because, though you repeatedly fail to accept it, there is a difference. You do not set out to brain damage your opponent when you play Rugby. Do you accept that there is a fundamental difference between boxing and other sports? I can only presume that you don't understand the difference. The difference is that of intent. Like the other difference you don't seem to understand- that between pharmacology and murder. Giving people physiologically active chemicals might be homicidal, or it may be medical. The difference rests solely on why you do it.
50. 1 point