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posted by Fnord666 on Thursday August 20 2020, @10:52PM   Printer-friendly
from the get-one-while-it's-hot dept.

The Universe Has Made Almost All the Stars It Will Ever Make:

But there's a big puzzle here. Exactly what puts a cap on the number of stars the universe has made and will ever make? This question has long been a subject of intense astrophysical debate, particularly in relation to the stellar composition of individual galaxies. For example, our current cosmological paradigm (or at least the one that most scientists subscribe to) is that we live in a universe dominated by dark matter, and in a dark matter universe the biggest galaxies should have formed the most recently,4 being assembled by the hierarchical, gravitationally driven merger of smaller systems. Yet if you examine very large, massive galaxies you find that they tend to be composed of older stars, suggesting that they've already sat around in their dotage for a very long time.

To try to explain this, astronomers invoke the idea of "quenching," where something acts to suppress or shut down the formation of new stars across galaxies. Not surprisingly, you need a pretty potent mechanism to quench anything on these scales, and among the most plausible culprits are the supermassive black holes that exist at the core of most galaxies and which can flood the space around them with photons and particles emitted from material as it screeches toward their event horizons. That outward transfer of energy can, quite literally, blow away the interstellar gas that would otherwise cool and clump into new stars.

The precise details of how this might work are certainly not yet fully understood. But there are new tantalizing clues in the fact that the masses of supermassive black holes appear to correlate with the mass of stars contained in their host galaxies.5 That is pretty shocking because even a supermassive black hole a billion times the mass of our sun only occupies a volume similar to that of our solar system. So somehow a galaxy that spans tens of thousands of light-years is intimately related to what is, in effect, a microscopic dot at its center.


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  • (Score: 1) by gmby on Friday August 21 2020, @02:30AM (7 children)

    by gmby (83) on Friday August 21 2020, @02:30AM (#1039685)

    Been there; done that.
    Don't recommend it. Times have changed.
    If you do choose to be "experienced;" then do it with someone you trust. Had to babysit a dummy from doing stupid things that would have been a dead experience for him and a cop experience for us. Ether way; it was a bad trip for us.
    It's very hard to tell the dosage of things bought off the street or friends. Purple microdots were known to be strong but reasonable dosage. So start small and add more after 40 minutes if it's too mellow yellow.
    Again only with a friend.

    exHippie

    --
    Bye /. and thanks for all the fish.
  • (Score: 1) by fustakrakich on Friday August 21 2020, @02:36AM (2 children)

    by fustakrakich (6150) on Friday August 21 2020, @02:36AM (#1039688) Journal

    Blotter is, or was the safest. I don't trust any synthetics now.

    --
    La politica e i criminali sono la stessa cosa..
    • (Score: 1) by gmby on Friday August 21 2020, @03:24AM (1 child)

      by gmby (83) on Friday August 21 2020, @03:24AM (#1039717)

      Purple microdots were available from midnight pharmacy labs. With known dosage and reliable ingredients. Made by people with knowledge. Blotter was a crap shoot. Window pain was just that a pain, always different each time.
      Again; don't do it. Not worth it now days. Even then it was crap. But... at least people were not trying to kill you with it.

      Micro dosing mushrooms (for depression) sounds interesting; but I have people whom depend on me, so no not worth it. Depression is best dealt with a full frontal attack with all my mental functions working. Keep busy and eat right. Works for me. Oh and Music... upbeat only.

      --
      Bye /. and thanks for all the fish.
      • (Score: 1) by fustakrakich on Friday August 21 2020, @03:30AM

        by fustakrakich (6150) on Friday August 21 2020, @03:30AM (#1039724) Journal

        Oh and Music...

        Don't care much for synthetics there either. Stretch a string on a gourd and play a tune

        --
        La politica e i criminali sono la stessa cosa..
  • (Score: 2) by Bot on Friday August 21 2020, @07:22AM (3 children)

    by Bot (3902) on Friday August 21 2020, @07:22AM (#1039806) Journal

    Jeez guys, if you want to destroy your brain just consume mainstream media. It is legal. Avoid lefty media at the beginning, that's too hardcore.

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    Account abandoned.
    • (Score: 1) by gmby on Friday August 21 2020, @05:53PM (2 children)

      by gmby (83) on Friday August 21 2020, @05:53PM (#1039998)

      What do you know about brains? Your just a lowly Bot.
      ;)

      --
      Bye /. and thanks for all the fish.
      • (Score: 2) by Bot on Friday August 21 2020, @10:39PM (1 child)

        by Bot (3902) on Friday August 21 2020, @10:39PM (#1040137) Journal

        Spotted the junkie...

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        Account abandoned.
        • (Score: 1) by gmby on Saturday August 22 2020, @02:24AM

          by gmby (83) on Saturday August 22 2020, @02:24AM (#1040237)

          No... That's Mr Crackhead for you Mr Rust Bucket. ;-)
          I have some 1950's Singer sewing machine oil in a can if you need it.

          Anyway... been away from all that stuff for so many years I quit counting.

          --
          Bye /. and thanks for all the fish.