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Carrock

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Everything posted by Carrock

  1. I can't find a good reference but triple point helium was used in the Apollo lunar descent engines so it's been around for a while.
  2. I don't know where that quote came from, but I doubt if Kavanaugh were accused in court that the judge could dismiss all his testimony, without ensuring Kavanaugh would have any conviction quashed on appeal.
  3. Are you implying that a universe containing aleph-one units of volume is possible? Reference please. Anything similar in maths would also be very interesting. Your construction produces a 2-D set of lines and these lines do not have lines for each point on them, which would require 3-D, then 4-D and ultimately at least aleph-one dimensions which is impossible. You can't connect these lines one after another in a 1-D line as that line would have an uncountably infinite length, which is impossible. I'm assuming all the points have to be discrete. I don't see any meaningful way of expanding a point into a volume. A more realistic question would be "Can a finite volume be doubled aleph-0 times, to become an infinite volume?" That finite volume would be increased by the factor 2^(aleph-null) which is aleph-one if you assume the continuum hypothesis. So aleph-one units of volume. I don't use trasfinite maths much so please excuse any imprecision in terminology.
  4. Surely you cannot expand anything other than an uncountably infinite collection of points into a universe of infinite volume (though the same would be true for any positive volume). Other than the trivial copout to expand by adding a sufficient amount of enough new points to do the trick, of course. The author of http://www.astro.ucla.edu/~wright/infpoint.html states the universe was spatially infinite 'before' BB. That's certainly possible but unknown. The problem is that he claims that each of the uncountably infinite points in that (finite or infinite) universe 'expanded' into a finite volume. That results in a universe with an uncountably infinite volume. Not possible.
  5. This is actually a rather mediocre reference. You can't expand a 0 dimensional point into a volume, and you can't expand an uncountably infinite number of points into a universe of uncountably infinite volume. As you go further back in time towards the Big Bang, the observable universe occupied a smaller and smaller volume but that volume, according to any reputable theory, was never zero.
  6. I was. Or wondering if he considered the cardinality of aleph-1 a bit nearer "Actual Infinity" than aleph-null and so on. Talking about cardinality seems a bit abstract for this thread. Do you believe that time will 'stop' at a specific moment in the future then? If it doesn't then the universe is becoming "Actually Infinitely" old. Which is less than infinitely old... Slow posting again.....
  7. Everything I was going to post has been posted while I was composing my response... except which is 'Actual Infinity' supposed to be? The number of integers, the number of points on a line... etc
  8. From https://en.wikipedia.org/wiki/Axiom_of_infinity linked from the previous reference:
  9. Presumably without the snake, Adam and Eve would have spent eternity naming all the animals. Who wouldn't be tempted by almost any chance of escape from that?
  10. Not being a true genius and having someone to actually express ideas to isn't always great either.... (Thanks to Strange for finding the site.)
  11. There's a very large gyroscope conveniently to hand. Wait around a few tens of thousands of years and you'll see it precess. Locals call it 'the earth.'
  12. There have been some excellent suggestions earlier in the thread. I can't improve on those. However, it's worth emphasising that if you come up with a valid proof of anything on this forum, and someone copies it, you can easily prove prior publication. That's what really counts in science and maths.
  13. It seems to be the sort of paid for journal which 'reviews' papers and always passes them. I couldn't find anything specifically dodgy, but at less than one citation per paper it's not exactly a prestigious journal.
  14. The only major funder of such expensive experiments is the nuclear industry, but they're not going to fund any experiment that may not give the right answer. They spent a fortune years ago investigating whether, as all the major models predicted, a sufficiently small group of people exposed to gamma radiation within the legal limits would not have a statistically significant excess of leukemia. Not too surprisingly, all these models held up. Their other claim, from that investigation, that that exposure increased the recipients' life expectancy by 6 years, was never submitted to peer review. It was said that the anti nuclear lobby suppressed this result.....
  15. There's still natural selection, in particular the decay of the aristocracy. e.g. https://boingboing.net/2018/05/17/gatsby-2018.html America's an extreme, but similar things happen everywhere. It's nice to be rich, but those of your children who have genetic diseases etc that would have killed them if you were poor survive and reproduce. Poor people have to be tougher and fitter to survive. Similar things happen with animals which have a hereditary aristocracy. In more stable aristocracies such as in Britain, outbreeding, e.g. marrying actresses or American heiresses is quite common and necessary to keep the bloodlines from weakening too much. It's quite reasonable to say that e.g. Meghan Markle, in genetic terms, married down. Lord Haw Haw, chinless wonders and the Upper Class Twit of the Year show are British recognition of this genetic decay. In short, if your family has old money and you're genetically unhealthy you'll be able to get good medical attention. If your family has old money you're more likely to be genetically unhealthy.
  16. Storing energy with trains going up and down a hill sounds ridiculous but it's already becoming commercial. https://www.aresnorthamerica.com/article/4875-advanced-rail-energy-storage-using-trains-to-store-power
  17. I did it, accidentally, then thought I'd cancelled it. I'm beginning to think the board software is a disguised intelligence test.
  18. So use tunnel diodes rather than the ordinary ones. I had thought transistors had overtaken them but not not entirely it seems as of 2013.
  19. I largely agree with Strange. However... The Josephson Junction is a (not very) handy esoteric alternative. Then there's Quantum Computing with Atomic Josephson Junction Arrays 1 and 0 at the same time (sort of) - two for the price of one. (Liquid helium not included.) Tunnel diodes, although quite fast and quantumy, never became fashionable as switches for some reason. 'Transistor' is a bit of a generic name. If they'd been invented after bipolar transistors, I suspect valves would have been called 'vacuum state field effect transistors.'
  20. There's the additional complication that most of these fruits are cultivars bred to be much less variable than wild fruits. I'd think lack of sunshine is the main reason tropical cultivars are selected to be sweeter than temperate cultivars. From mainly childhood memory in Scotland: Ripe wild strawberries are tiny and less sweet than cultivars but with a much better texture. They were quite rare in Scotland and I may have mostly eaten them from one large patch spread by runners. I preferred them to cultivars but that may have been because they were so hard to find. Wild blackberries aka brambles are much more variable. Ripe blackberries range from very sweet and tasteless to very acidic. I prefer the somewhat acidic ones and I suppose some birds and animals do too; there may be nutrients lacking in the high sugar blackberries. When I've bought blackberries they've never been as sweet as the sweetest wild blackberries. An interesting question is whether wild tropical fruits are typically sweeter than wild temperate fruits. Bit more complicated. Many fruits taste bad and/or may be poisonous to some animals so that only preferred creatures e.g. birds spread them more efficiently. e.g. deadly nightshade tastes quite good to humans but you won't come back for a second helping.
  21. We have a clash of values here. As I never wanted to be a professional programmer or write safety critical applications I went the quick gratification route. My idea of 'good programming practice' is to copy and paste from well written software and edit in my own variables, code, comments etc without understanding the source software more than I need to. phpbb has good software which lends itself well to this approach. +1 to Strange for an excellent exposition. I'd suggest to the OP starting with free software as you can waste a lot of money on commercial software you find too late you don't need. Xampp is basically an apache server with many safety features disabled so that it can be easily modified for developing e.g. a virtual server or website offline. It's not a PHP interpreter. Better but harder to use alternatives are available.... (I'm too lazy to try them.) I'm a bit dubious about the W3Schools PHP online "try it editor." Anything slightly unusual tends not to work on it. I went the xampp route after wasting hours trying to debug software that had nothing wrong with it. (W3Schools has probably improved since then.) Xampp is very easy to install. There's even a windows version but it's easier to manage the security implications on Linux. /edit It's also worth installing a database which can work with xampp. Database management is another valuable type of programming.
  22. I've dabbled around and found php by far the easiest to learn if you want to do something rather than pass a course. It's a server side scripting language used e.g. in any website with .php in the title. Unlike eg the similar C++ it usually still runs (with helpful warnings and bug reports) if you make small mistakes. My understanding of php is strictly 'need to know' but it seems to be a sort of hybrid of a compiled and interpreted language. I ran a phpbb board for a club for a while. There were things it wouldn't do that I wanted so I installed xampp and phpbb on my computer. On my computer I set error reporting to full (big security issue on a server) and soon learned what I could and couldn't do with the open source code. I was told by a club member there was a serious shortage of php programmers even at my (very low) level but wasn't interested in it professionally.
  23. A forum with a stronger interest in practical astronomy might be better than here. I haven't looked at https://forum.cosmoquest.org/ in years, but it's probably worth a try.
  24. That depends on what philosophy you want to do. Even discussing this with you requires the assumption there is "something called 'I' which is conscious of thinking" associated with you (e.g. you're not an unthinking AI program), and myriad other assumptions. Do some philosophy using only "There is something called 'I' which is conscious of thinking." X composed with Strange.
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