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Endy0816

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Posts posted by Endy0816


  1. 2 hours ago, geordief said:

    It is the model that shows two objects as being at rest,isn't it?

    Normally only talking about the X, Y, Z coordinates being unchanging with respect to something to define at rest. While there is always be something increasing or decreasing in distance from you(relative motion) we also don't define being at rest in universal terms either.

    We are all always 'moving' at 1second per second though in terms of time. This is still change in respect to your previous coordinates.

    ie.

    X, Y, Z, T

    vs

    X, Y, Z, T+1

     

     

     

     

     


  2. 2 hours ago, Charles 3781 said:

    Thanks Endy.  Do you think the photograph of the supposed "Black Hole" id very convincing.  It  looks like a blurred  image of a distant  planetary nebula.

    As for "Dark Matter",  is there really such a thing.  There's no evidence for it.

    Except  to account for apparent anomalies in galactic rotation.

    But might these anomalies be explained, more normally, by  the presence of meteorites within, and outside the galaxies.  

     

     

     

    They are crazy dense, but not big relative to their accretion disc. If you could get close to one, would look more interesting. Conservation of angular momentum is the underlying mechanism so will look the same a a planetary nebula or even our own solar system, spiraling around a central point as they do.

     

    Yes, dark matter is real. Doesn't interact with light though.

    https://ysjournal.com/cosmic-web-seen-for-the-very-first-time/

    x-posted

     

     

     


  3. 1 hour ago, Charles 3781 said:

    Personally, I haven't reproduced a single off-spring, as I preferred other pursuits

    Well that's me done then. I haven't produced any off-spring. No reproductive success whatsoever.

    How have you done?  

    Same(probably), though note a relative's genetic success can be as good as if not better than your own to an extent.

    We're all pretty similar too on the whole, so not really bothered by it personally, especially with this sheer mass of humanity that we have today. Genghis Khan would even have a run for his money, with a population of over 7 billion.

     

     

     


  4. 1 hour ago, Charles 3781 said:

    Do you think the "photograph" of the "Black Hole " is real?  

     

    We can observe the accretion discs that form around them, the impact their gravity has on other masses in their vicinity, gravitational waves. That sort of thing.

    Similar story to dark matter. All we have been able to 'see' is the shadow cast by hydrogen attracted to it, but we knew it was there already by the impact it has on galaxy rotation.


  5. 52 minutes ago, StringJunky said:

    On a sobering note, mentioned by  some election statistician, a sitting President hasn't lost their second election for forty years...

    Da, it  normally only flips every 8 years.

    Been an... interesting... four years though so I'm hoping we get lucky.


  6. Disney has some cool ones for use as stunt robots.

     

    Besides battery life, main roadblock is that they tend to focus on one particular area rather than the more rounded sort of requirements a terminator might have. I think if we really wanted to we could do it within a few years.

     

    9 hours ago, Strange said:

    The bigger question is: when will we be able to send the Terminator back in time?

    Well most times around Skynet doesn't invent it until later in the war. This last time was an outlier though and it came up with temporal displacement early on, so you never know.

    Edit:

    10 hours ago, studiot said:

    I just caught part of a TV program called Spy in the Wild.

    BBC1 1735 - 1835 today.

    I will have to complete it on iplayer /catch up.

    It shows the most amazingly realistic robotic artificial animals designd to fool real animal herds in the wild in order to video the.

    These robots look like the real thing, orangutangs, crocs, egrets, penguins, sea otters etc and have sound vision and realistic action.

    Just wanted to add that this is a really good program and they have parts of it on PBS and youtube, if anyone is interested.


  7. On 7/30/2020 at 3:53 PM, Oakmrkeii said:

    So i had a thought, (most if them are dumb, this one may be too) if someone makes Lab grown bones in the shape of "devil" horns, would it be possible to attach it to their skull? Just to put there, not to grow or anything. Im guessing there's a lot of things wrong with that, but I was curious of if it would be possible. Also, could there be a possibility part of the bone could be left showing, and it be attached around the bottom to make it look more like actual horns. Would the body reject them? And what complications could arrive, or are there too many to count?

    Transdermal implants can be done. Lab grown horns probably not.

    Practical issue is that the cells won't develop into particular shapes on their on. Foreign cells would also greatly raise the risk of rejection.

    You could conceivably shape an existing bone into a horn shape though.


  8. Some studies on low gravity pregnancies, suggest the children might develop abnormally and find dealing with higher levels of gravity borderline impossible, while others suggest the embryo might fail to develop at all.

    So I'd say your fist idea is pretty plausible, may need to be larger though to avoid nausea.

     

    As to the second, you are talking about a Utopia. Be nice, but we have a long ways yet to go as a society. On the whole things are gradually improving though.


  9. 12 hours ago, Externet said:

    From a years old thread, seems these Tuareg people know how to deal with it better than anyone... I still do not get how they do it.  Body temperature is less than ambient :wacko: Since milennia before hi-tech fabrics...

    Tuareg Libya Africa local man camels nomadic people nomad nomads ...

    And not always in white :

    The Tuareg Salt Caravans of Niger Africa

    -Images borrowed from the web-  If against rules, please delete.

     

    Found an interesting article on this:

    Quote

    The results were clear. As the report puts it: "The amount of heat gained by a Bedouin exposed to the hot desert is the same whether he wears a black or a white robe. The additional heat absorbed by the black robe was lost before it reached the skin."

    Bedouins' robes, the scientists noted, are worn loose. Inside, the cooling happens by convection – either through a bellows action, as the robes flow in the wind, or by a chimney sort of effect, as air rises between robe and skin. Thus it was conclusively demonstrated that, at least for Bedouin robes, black is as cool as any other colour.

    https://www.theguardian.com/science/2012/aug/19/most-improbable-scientific-research-abrahams

     

    Granted be curious to find out how much an impact higher levels of humidity would have.


  10. Agreed that most mega-projects while not feasible with purely human labor, are more than feasible with enough machines working for/with us. Think once we get automated transport and farming finished up, we'll be in good shape to consider more. These projects won't be free from opportunity cost, but that cost can be made smaller.

     

    We do have private spaceflight taking off. Bit biased, but think tourism is going to be an important first step along with these ever larger satellite constellations.

    https://techcrunch.com/2020/08/10/spacex-reveals-plans-for-a-texas-spaceport-resort-in-new-job-ad/

    If we can get to the point where space station relocation is the norm for in-system colonization, we'll be better equipped to start looking at expanding outside the solar system.


  11. 3 hours ago, Markus Hanke said:

    Indeed! Good point ;)
    This essentially renders the entire scenario unphysical, because you can never make the total distance =1m, regardless of how close to c you get.

    Yeah. It's interesting that the Universe could have a finite volume but still be impossible to cross.


  12. Realistically you will always have some kind of hard/wetware to worry about.  You might have access to a  hyper realistic simulation but you will still have some kind of body.

    Could see variety of artificial methods used to sustain the population, if necessary, though doubt that it will be.

     

     


  13. 3 minutes ago, Tom Booth said:

    Not really.

    The formula for heat engine efficiency is: Th - Tc / Th.

    On a scale that begins at absolute zero.

    So if a heat engine reduces the temperature of the heat from T-hot down to T-cold that is simply the percentage of cooling produced on the absolute temperature scale, or how far the engine has cooled the "working fluid" on the way down to absolute zero.

    It simply states that at best, the engine cannot reduce the temperature any lower than Tc.

    It derived from Carnot who conceived the "flow of caloric" as including all that caloric down to the absolute zero temperature.

    The "rejected" heat is the un-utilized percentage of caloric below Tc down to absolute zero, which Carnot conceived as also flowing through the engine.

    That is the actual original basis of this engine efficiency formula.

    That is, of course, my understanding after some rather extensive reading and research on the subject.

     

    You'll always have some losses though.  You mentioned swapping out the bolts to reduce parasitic losses for instance.

    Note the idealized nature of the Carnot equation. Any real engine will have all kinds of issues reducing theoretical efficiency.


  14. 3 hours ago, MigL said:

    Grown men don't play with dolls, Endi.

    *Tucks Universe back into pocket*

    Balloon example is all good until someone asks you about those dots expanding or us colliding with Andromeda, lol.


  15. 3 hours ago, HAMKiiNG said:

    Please excuse me as i am trying to simplify this as best as possible without having to draw a picture 😃

    I questioned earlier about perpetual motion and it led me to idea no2.

    You have two cylinders.

    One filled with water and one in a vacuum.

    You have a container that is denser than air but still buoyant.

    The container passes through the water filled cylinder pulling a cable that turns a generator.

    Once it reaches the top it passes into the cylinder with the vacuum and falls to the bottom still pulling the cable.

    Would this create a positive energy output?

     

    It would just end up floating on top of the water.


  16. 4 hours ago, Paul Singh Jr said:

    I do know that the Big Bang Happened practically everywhere but some ppl  recently theorised that all matter came from one source 

     

    The space we and everything else is occupying today is where that 'source' was. Everything was at a single point(roughly speaking) before that became less dense.

     

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