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GeeKay

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About GeeKay

  • Birthday 10/19/1950

Profile Information

  • Location
    Lincoln UK
  • Interests
    Cycling, swimming, reading, writing and generally making the best of life. I intend to do a lot of motorhome-style travelling in the nearish future, complete with my favourite touring bike and a decent sized telescope. And I'm looking forward to it - immensely.
  • College Major/Degree
    BA (hons) English Literature at the University of Wales, Aberystwyth
  • Favorite Area of Science
    Astronomy
  • Occupation
    Ex-private tutor (English Lit). Now retired.

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  1. Yes, I think I begin to get it now. Thanks, studiot, for your detailed and helpful explanations. Food for thought, indeed. G
  2. It could be that the use of the adjectival 'super' in superposition has been confusing me. If measurement is the key that defines whether a quantum system is in superposition or not, then what about measured versus unmeasured? Personally I suspect the opposite of Spain is located somewhere in the South Pacific. . .
  3. A few years ago one of my nieces, then aged twelve, asked me what "the opposite of superposition" is. Her question completely stumped me at the time. It still does. I have since considered placeholder answers like: normal position, position, classical position, etc. None of them seem satisfactory, however. This same question (with full quotation marks) also continues to stump Google. NB. I am prepared to be told that the question is nonsensical - that it'll be like asking what the opposite of Spain is, for example. Still, I'm up for it.
  4. Regarding ventilation: this used to be potentially an issue given the room's double glazing. It was necessary to block off the window's trickle vent, this due to the wind persistently recreating Bob Dylan-like harmonica sound-effects with it (worse still, given the prevailing wind direction in this part of the world, the house itself is situated near the top of a south-west facing hill with an uninterrupted view of the horizon). The room isn't particularly dusty, although I will now give it an early spring clean. Allergens remain an unknown at present. On the other hand, I do keep the door open at all times, beyond which is a landing which in turn leads to the stairwell. Meanwhile, the ambient humidity level outside the house is 91% at the time of writing, while the temperature is just 2 degrees Celsius. This high humidity count is actually fairly typical in this part of England. What is confusing, though, is the relationship between temperature and humidity. Do people living on the equator who routinely endure both high temperatures and (say) 100% humidity levels suffer from respiratory problems? Or have they adapted to these conditions in the same way that people living at high altitudes have adapted to low oxygen levels due to the thinness of the atmosphere? Extremely puzzling, that. studiot, I note with interest your own high humidity readout. To reiterate: in respiratory terms I really do feel better for having a count of between 65% ~ 70%. I just wish I knew why.
  5. This is from a person who spends several hours a day word-processing in a smallish upstairs boxroom (2.4m x 3.8m) that faces south-west. The room is centrally heated (20 C) and efficiently double-glazed. For sometime now I have suffered from minor, but persistent respiratory problems, stuffy nose, throat-clearing issues. I also have chronic sinusitis, which I plan to do something about just as soon as Covid-19 finally abates. . . whenever that might be? Meanwhile, these respiratory problems have all but vanished since using a humidifier. It seems that it more than compensates for the room's dryness, which may be due in large part to running two PCs, plus a UPS battery system and other electronics. What is puzzling, though, is that the full benefits only arise when the room's humidity levels hover around the 70% mark. This must be mentioned because it's routinely cited that optimum humidity levels should be between 30% ~ 50%. This is waaay too low for me, which means either I'm an exception (i.e. a naturally 'wet' person) or else I'm failing to understand something fundamental about humidity. Any comments/suggestions welcomed. Apologies for the repeated usage of the first person singular. Unfortunately the issues related above apply particularly to the poster.
  6. It should bother you - if only because the "wilfully ignorant" tend to vote into office the kind of dickheads who are currently doing the rest of us NO favours whatsoever. Anyone care for a re-run of 2017? Then there's this. . . https://www.nytimes.com/2019/12/28/climate/trump-administration-war-on-science.html
  7. This is a valid point. . . as far as it goes. It's just that it's not enough any longer. In the age of the internet it's no longer a matter of leading a person to a book; rather it's a case of leading the book to the person.
  8. Many thanks for the link. Yes, the fact that both are just opinion pieces illustrates how so-called "truthers" like Mark Steele can patrol their chosen agendas the way they do. This is more an internet problem than a purely science-based one. Still, speaking as a layperson/armchair observer here, it might be helpful if scientists took on Steele and his ilk more directly. There's no chance of getting such folk (and the majority of their camp followers) to alter their views by reasoned debate, of course - not when these views are buttressed by emotional convictions. All the same it would surely help the many undecided, even the merely disinterested. Just an observation.
  9. Is there any truth in the proposition that 5G is harmful to health? Many thanks. https://blogs.scientificamerican.com/observations/we-have-no-reason-to-believe-5g-is-safe/#
  10. swansont - many thanks for your succinct answer to what has been a long-term headache for me. Much appreciated!
  11. I am tying up the loose ends of a SF short story I wrote last year, featuring a neutron star. Right now, though, I'm stuck over a long-term problem concerning the star's luminosity. It's surface temperature is 8,200 K and has a diameter of 20 kms. My problem has consisted of trying (and failing) to calculate what the star's absolute magnitude would be. I'm afraid this is beyond my abilities to solve, and unfortunately I don't know anyone among my friends who has the mathematical nous to help me out here. So I would be extremely appreciative if someone here could put me out of my misery. Many Thanks!
  12. What would be the theoretical maximum spin-rate of a small asteroid (25 - 100m diameter?) if it were, for example, composed of a single 'monolithic' chunk of iron? This question arose after reading up on the subject in a Wikipedia article. Listed in it is one such asteroid with a spin-rate of around 30 seconds. Could this be bettered, given the above parameters? Many thanks. https://en.wikipedia.org/wiki/List_of_fast_rotators_(minor_planets)
  13. Yes, I understand now. In other words the only 'practical' way for an object to decelerate while passing through an intense gravitational field would depend on powered means, not inertial. Moreover, the fact that the incoming object is moving at 0.01c relative to a given mass would (I should imagine) rule out all variations of power assist - this insofar that the proper velocities of nearly all stars aren't remotely relativistic, that's to say within local frames. Many thanks for clearing up this matter for me.
  14. I'm wondering if it's possible to use the gravitational field of a massive object to decelerate a spacecraft moving at high velocity. An example is this: if a spacecraft moving purely on inertia at one percent light-speed performed a flyby of a one sol mass neutron star (or black hole) at a given altitude, would the gravity field cause the spacecraft to swing round the star, slow it up or else deflect its trajectory in a meaningful way? According to one online calculator the escape velocity of a solar mass neutron star at a distance of 25,000 km equals 3,000 km/s or 0.01 c. At this distance the tidal pull exerted by the star's gravity would be minimal, therefore represent no hazard to the ship or its crew. That said, I'm curious to know what would be the outcome. PS. It's the escape velocity I'm interested in: not the star's proper motion as a means of affecting a change in delta-v. Many thanks.
  15. Hi Yes, I'm looking forward to trying out these ideas once I get the offending discs back from a friend of mine whose been investigating the problem. I'll start with Phil for All's solution - this being a likely cause, given my tendency to fumble around with the player remote when watching films in subdued lighting. Failing that, I'll attempt to change the movie's audio setup in the discs' formating options (thanks, Memammal) and see what happens. Again, thanks for all the helpful advice - I've learnt a great deal from it
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