Jump to content

John Cuthber

Resident Experts
  • Content Count

    16964
  • Joined

  • Last visited

  • Days Won

    26

Posts posted by John Cuthber


  1. On 7/6/2020 at 11:19 AM, swansont said:

    An omnipotent being can do whatever they want.

    Could an omnipotent being set himself a goal he can't achieve?
    If so, he's not omnipotent, 

    if not, he's not omnipotent.

     

    On 7/6/2020 at 8:22 AM, Ken123456 said:

    Could God...

    Depends on the God.

    There are lots to choose from.
    It' not clear that any of them actually exists.

    12 hours ago, Ken123456 said:

    Presently Satan owns the earth and all who do not wish God to be their savior.

    This leads to the interesting question of why God created Satan. (or equivalently, why did God, knowing what would happen, choose to put the Serpent in Eden?)


  2. 44 minutes ago, HallsofIvy said:

    How does that contradict what I said?  A person who is on the dole still needs money- staying alive is not living in a satisfying way!

    They have enough money to stay alive. But if you actually ask them (which is what I actually said) they say they want a job.

    It's the self respect that does it.

    You pretty much said it yourself:

    47 minutes ago, HallsofIvy said:

    staying alive is not living in a satisfying way!

    Most people want the satisfaction of actually achieving things.


  3. There is no longer a "standard" metre rule, we have a different definition of a metre these days.
    However, when there was a single standard- (all the others are copies) it looked pretty much the same as this one.
    https://en.wikipedia.org/wiki/History_of_the_metre#/media/File:US_National_Length_Meter.JPG

    It has, so I understand, two marks on it about 1cm from each end. The bottom of  middles of those marks are 1 metre apart.

     



     


  4. On 6/22/2020 at 2:05 PM, studiot said:

    Government after government has committed increasing and enormous sums to the HS2 rail project so that a handful of businessmen can travel from London between Birmingham a few minutes more quickly.

    No they have not.

    That's the straw man version.

     

    The actual reason is that having a second line doubles the capacity which should cut down on the delays which, in addition to being annoying, are expensive.

    It means that the local services don't have to stop + get out of the way of the mainline ones.

    The real question is why is it so expensive.


  5. 12 hours ago, Airbrush said:

      What person is NOT going to eat something delicious that they are told NOT to eat?  That is like saying "please eat this!"

    The Serpent pretty much did say "please eat this".

    Don't forget that God put the serpent into the garden.
    Nobody seems to know what He did that.


  6. 4 hours ago, drumbo said:

    Watch the video below by the scientist William Happer.

    From WIKI
    "In 2018, Happer, who is not a climate scientist and who rejects the scientific consensus on climate change, joined the National Security Council of the Trump Administration to counter evidence..."
    Why would I watch that?

     

    4 hours ago, drumbo said:

    Right now we have too little carbon dioxide.

    What harm is the "lack" of carbon dioxide doing?

    On 6/16/2020 at 7:55 AM, FishandChips said:

    I am really confused now one guy was telling me its a hoax fabricated by socialists and feminists. What are your thoughts ?

    Who is more likely to be able to fund a conspiracy, the hippies or the oil companies?


  7. The weird thing is that you can find a concentration of about 10^31 electrons per cubic metre in most of the universe.

    A hydrogen atom has a volume of about 6*10^-31 cubic metres, and contains 1 electron.

    What you are talking about is a million times higher- (because  there are 100 cm in a metre).
    So, we need to find something where the electrons are pulled into an even smaller space.

    One way to do that would be to increase the charge on the nucleus- Instead of using hydrogen, we can use uranium  with 92 times the change.
    It's a bit tricky y to strip off all but one of the electrons, but it's not impossible. 

    That gets us into this realm

    https://en.wikipedia.org/wiki/Hydrogen-like_atom

    And I think that , using tehNohr model, the radius is inversely proportional to the charge. (though it's safe to assume that relativity screws that calculation.)

    In which case you can, in principle create a very small volume of  space, very near the nucleus of a transuranic element, where the electron density is that high.

     

    Calculating the effective temperature is left as an exercise for the interested reader.

     

     

     

     


  8. It's never a good sign when someone says "I want to do this" and cites a clip from an action movie.

    Also

    7 hours ago, fredreload said:

    I am looking for a really strong type of glass that would withstand the pressure and the thermal energy that would be generated in this medium some 1 million kelvin.

    Nothing will stand a million K.


  9. Metals block light very effectively (unless they are extremely thin)

    So, a small metal box  (with some padding) would do the job of keeping your B12  bottle in the dark.

    The photography stores used to sell opaque bags of various sorts for handling and string photographic film, but in these days of digital imaging, I don't know if they are still on sale.


     

    4 hours ago, ahmet said:

    only alimunium as far as I know , it is one of (presumably the english equivalent terminology for it is: ) "prime metal" 

    what does it mean? : this is a class as I know in periodic table.

    others are "Zn,Pb,Cr" all these are also prime metals (maybe I confuse this with half metalic metals,not sure).

    their properties have both metalic and ametalic.

    I'm sorry, but none of that makes much sense.

     

     


  10. 14 hours ago, swansont said:

    and, as I said earlier, there is absorption (and possibly transmission), so you eventually run out of photons. 

    In a good cavity, the lifetime of a photon is still much, much less than a second.

    good cavity, 2 ns lifetime:

     

    That's not a good cavity.
    This is an article about deliberately absorptive cavities with time constants over a thousand times longer.
    https://en.wikipedia.org/wiki/Cavity_ring-down_spectroscopy


    Though it's still well below 1 second.

    (As an aside, I suspect the LIGO cavities would have a ring down time constant of over a second; that's a really good cavity, but not terribly practical.)

    More importantly, back at the topic.

     

    Isn't "almost infinite" the reciprocal of "practically nothing"?


  11. 3 hours ago, mo.sabith said:

    (Sorry if this seems obvious/stupid)

    Correct me if I'm wrong. AFAIK when temperature is decreased, the molecules become closely packed,  thus increasing the density.
    Then how do we say that the universe was extremely hot at the beginning when it was all packed into a few cubic centimeters?

    The pressure was high.

    Very high.


  12. 4 hours ago, StringJunky said:

    Love your dismissive tone

    Interesting phrase in a post where you dismiss someone's view without offering any reason to say that the view is incorrect

     

    2 hours ago, StringJunky said:

    This is your opinion. Stop talking like it's fact.

    Would you like to borrow a mirror?.


  13. 30 minutes ago, studiot said:

    Who said it does ?

    Oops!

    Boils at 1465, but the point still stands.

    It has a boiling point, so it doesn't decompose.
     

    31 minutes ago, studiot said:

    I did wonder why they talked about electrolysis, but what did they say that was factually incorrect ?

    Yes, notably, if it decomposed to form chlorine, it wouldn't have a boiling point.

     

    32 minutes ago, studiot said:

    Does sodium chloride ionise when it melts ?

    A matter of definition, but the solid is composed of a lattice of ions.
    It's already ionised as a solid.

    32 minutes ago, studiot said:

    Well most alkali halides apparantly do.

    To whom is this apparent?

     

     

    33 minutes ago, studiot said:

    If molten sodium chloride does not ionise (ie decompose on melting) how does it conduct electricity and what species are present in the melt?

    It's ionised as a solid and as a liquid.
    In the solid form, the ions are not mobile.

    In some other compounds, even the solid conducts by the movement of ions.

    https://en.wikipedia.org/wiki/Rubidium_silver_iodide

    https://en.wikipedia.org/wiki/Silver_iodide

    (Above 420K)

     

    36 minutes ago, studiot said:

    I see that someone who has not the guts to say why does not like my genuine attempt to help.

    Because it's factually incorrect.

     

    On 6/1/2020 at 9:38 AM, studiot said:

    My comment was about safety.

    Scaremongering, (deliberate or accidental) doesn't help anyone.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.