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Col Not Colin

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Everything posted by Col Not Colin

  1. Hi all and thanks for these replies. I'm cautious. Trying to identify the motivation for online activities is key to staying safe and savvy. Volunteers sounds good but it must cost money to keep a server running. Asking where the funding comes from seems a sensible question. Good news, I'm not planning to complain. At the moment my main motivation is not wanting to be a part of any activity that shouts down newbies. Well, thanks Blake. You were probably trying to do a good thing. I think that's what I was looking for, a place for discussion about science
  2. Hi everyone. Is there an "about" link for this forum, similar to the type of thing most websites provide? Can I ask the following sorts of questions: 1. In a short paragraph, what does this website or forum aim to do? 2. What affiliations or structures exist (e.g is this a subsidary of We-are-foums-dot-com)? Where does the funding come from? 3. Is there a registered office and/or a conventional postal address for this organisation? 4. Is there an internal complaints procedure? - - - - - End of introduction, setting the scene etc. Informal, c
  3. No-one gave the website for live coverage. https://www.nasa.gov/content/live-landing-of-the-mars-2020-perseverance-rover
  4. Hi Beecee and thanks for your article, I enjoyed reading that. Some evidence that dark energy is not uniform, thank you very much +1. Yes, total agreement on this. Even if there was some expansion of space, strong short range forces will dominate so that atoms and molecules don't tend to fly apart. The same applies upto scales of the local group where we can say the constituents are gravitationally bound together. It doesn't matter if space is expanding there, this can be overcome as you stated. I think this was discussed earlier on in this thread (Bufofrog, Joigus and Janus shoul
  5. Hi Swansont, Thanks and best wishes to you. I think the main thing I wanted to get across was that the expansion of space may not apply uniformly. It applies on the largest scales of distances between distant galaxaies but not necessarily on the scale of lengths between atoms in a molecule. However, yes, since we don't have an adequate understanding of dark energy the typical form of the Einstein Field Equations with a cosmological constant may not apply on these small scales, if you want to look at it that way. Dark Energy can mean several things. Here's a few id
  6. Ummm.... I'm not sure what you're asking. I try to have an opening that just says "hi" or otherwise sets a more reasonable scene for discussion. You could take it out if you wanted but the rest of the post may seem a bit too hard and direct then (and I really wouldn't want you to do that). Statement 1 was intended to soften the impact of the rest of the post rather than making it appear to be an outright disagreement. I do like General Relativity and would like to suggest that I am not the enemy or deliberately antagonistic to any view that GR should be applied to all situations.
  7. Hi @Markus Hanke, hope you are well. I like GR as much as the next person and I'd love nothing more than Einstein's Field Equations to apply everywhere with a cosmological constant - but is that enough to overlook the level of ignorance we have about Dark Energy? What makes you so sure that the Einstein Field Equations with cosmological constat applies to such small scales as a bond length within a molecule? We don't have an exact value for [math] \Lambda [/math] but just an approximation based on Astronomical observations and this includes adjusting the proportion of dark
  8. @iNow I don't want you to feel under pressure but if this isn't good, I'm going to cry all night. Then I'm going to come back here and change my +1 to -infinity. Seriously, thanks for the suggestion. I'm going to give it a try.
  9. Skipped through the rest of those (two) videos. It's just a short survery or lunchtime interest thing over two lectures. Dissapointing, no graphics, no Mathematics, very brief. Might have been useful if you were there and could have asked questions but as a YT video, less useful than watching a good documentary. Still seeking recommendations for a good Cosmology lecture series.
  10. Hi @Airbrush Hope you are well. Yes, although the emphasis probably needs to be put on "dark energy" and we might just as well replace it with Neil deGrass Tyson's favourite description of it as "badly behaved gravity". We don't have a good understanding of what it is or where it is. Perhaps it's not even a physical thing but just a requirement that the metric is found from an equation with a suitable cosmological constant. Finally, perhaps it's a sign that our model of gravity is breaking down. It's badly behaved gravity that is yet to be explained. We are reason
  11. WANTED: Recommendation for a Cosmology Lecture series. Hi everyone. Not sure where to locate this post. Can anyone recommend a more up-to-date lecture series I can watch with similar detail and presumed background knowledge? I've seen this one and I can recommend it to others. Full lecture series on Cosmology from standford University available on Youtube (from 2013). https://www.youtube.com/watch?v=P-medYaqVak&t=1549s There's another full lecture course in the MIT opencourseware series on YT (from about 2014): https://www.youtube.com/watch?v=A
  12. Hi again. I've been watching this thread for a few hours now and I can't help but feel that some earlier responses (including mine) have come over fairly negatively. For example, I'm really sorry that this thread was moved from Astronomy and Cosmology to Speculations. That is usually a decision made by ? whoever runs the forum but usually there is some explanation given for the move. Speculations does not mean "rubbish", there is actually a "trash can" section in this forum if someone felt it had to go in there. Presumably the post just seemed to meet the criteria for speculatio
  13. Hi IRW03..70, hope you are well. I can do some humouring. Firstly, it's obvious you have spent some time thinking about this, getting some diagrams, some completely original ideas and some existing ideas from science all brought together. That's good. There's always a place for new ideas and we should certainly be encouraged to let imagination run wherever it wants sometimes. Let's not be too general but instead look at the specifics of your work - there are a few things you have mentioned that are really, really very good if not revolutionary. Congratulations. Additionally
  14. Hi @beecee, Yes GR is definitely a significant contribution and I nearly said that. Not sure about Carl Sagan but that's just a geography thing. In my part of the world we had other science presenters. Hi @Janus, Also a good suggestion. Thanks for quoting me but I think it was Wildie9 who started the new discussion - so I'll wave his flag. @wildie9 You may also want to read some of the above.
  15. Hi again. Thanks for explaining your requirements. Sadly, I'm not an expert on higher order logic and it seems unlikely I'll have time to become familiar with it over the next few months. So I'll be bowing out of this conversation. Sorry I couldn't help. Best wishes to you, bye for now.
  16. Hi again. You could start another thread for what is another topic - but it's your call. Greatest contribution to cosmology? The Hubble Law. Obviously, just one opinion.
  17. @slomobile I'm still not really sure how to use the messaging system. If you need anyhting else write something here. Otherwise, best of luck to you with your work, bye for now.
  18. Hi. Will this do? But it can be annoying anyway. Maybe best to leave it as a static link in text. I have limited ability to explain how you make it work, I just right-click on the embedded object and fiddle with settings and stuff until the post looks ok.
  19. Hi Markus, hope you are well. In this context, I would define an amount of space (between the earth and the moon) as being something that is measured by the distance between the earth and the moon. Agreed. I said... The FLWR metric doesn't have to apply to such small regions as the bit of space between the Earth and the Moon... and maybe that should have been "doesn't" instead of "doesn't have to". The rest of the paragraph did discuss the better metric to use for that region of space given the exact distribution of mass that it has. Agreed. Space i
  20. How does science model it? Well, that one can be answered. The usual model of the universe (on the really big scale) is General Relativity with the FLWR metric (given various names but LeMaitre, Friedmann, Robertson and Walker contributed and at-least a couple of these names get used). All that's important is that the spatial contribution to any proper distance measurement is multipled by something called the scale factor and this grows with increasing time. How you explain or visualise that is, as you say, largely up to you. It is a mathematical model and not any other sort of model.
  21. Hi Zapatos, hope nobody minds me joining in. Well, yes you could think of space as "flowing" past an object that was bound in place by gravitational attraction to something else. I've seen several animations of space that do exactly this - show a steady flow of space as if it is something like a fluid flowing. That's ok. Alternatively, you can think of the expansion of space in a different way. Instead of space being stretched or any part of it being made to "flow", you can imagine that it is a reasonably fixed thing that can't stretch at all - there is just simply more of
  22. Hi again @confused2021. I think I wrote 0.02 here when I meant 0.002. Anyway, hopefully the spirit of the discussion is solid even if the typing isn't. Also, isn't it great to know that other people can make mistakes? Got to look on the bright side. Also, @Bufofrog , I wish I had seen your reply first, would have saved me a lot of time typing. (I'm also secretly hoping that you'll run out of time to correct your spelling of Miles <--> Moles, then we can all have a typo).
  23. Hi. I've only had time to scan through what you've written. Thanks for putting your own answers in here, we can see what you have done and what efforts you have made, that's great. In question 1, what you've done is reasonable but does seem to have a slight error. This could be just an arithmetic or trivial error, in that case.....well, ok, we all have those. BUT it could be a conceptual misunderstanding which we can do something about. We can also suggest a method to check your conversions make sense and reduce the number of accidental errors. A Molar concentration is
  24. Hi again. Godel has been mentioned everywhere so I assume you are aware of Godel's second incompleteness theorem. I'll para-phrase it here: Where P is the Peano arithemetic system, we have the result that the consistency of that system cannot be proved (unless P is actually inconsistent). This provides a fairly simple statement, ¬Prov("0=1"), in the Naturals which (almost) seems to meet your criteria. If that's all you wanted. See the references given earlier by wtf, I've tried to use the same notation. Why do I say ALMOST meets your criteria? It does not establis
  25. Puzzlement: This is extremely unusual. The language used by Tristan L is sometimes extra-ordinarily precise but it is frequently unusual. Some examples: "ownships" used in the OP instead of properties; A hyperlink to witcrafty that seems almost irrelevant. On brief inspection witcrafty seems to be a website about the formation of words. Brief inspection of some other posts Tristan has created or contributed to include one about entropy where an alternative way to patition microstates was presented that seemed to involve runes and the ability to communicate with ru
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