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Supermassive Black Holes Not So Big After All

An anonymous reader writes "Supermassive black holes are between 2 and 10 times less massive than previously thought, according to new calculations published by German astrophysicists (abstract)."

15 of 153 comments (clear)

  1. but but by Dyinobal · · Score: 3, Funny

    but they are still super massive right? If not that totally ruins most of my celestial bodies jokes.

    1. Re:but but by funaho · · Score: 3, Funny

      Your momma's so fat the only thing keeping her upright is electron degeneracy pressure!

  2. Sheesh! by Anonymous Coward · · Score: 5, Funny

    You mean, they're only hundreds of millions to a billion times the mass of the sun, not several billion times the mass of the sun? Sheesh! Talk about phoning it in! Wake me up when they're serious about being 'super massive'!

  3. Math? by LocutusMIT · · Score: 3, Insightful

    How can something be X-times less massive than something else? I can understand half as massive, or 1/10 as massive, but two to ten times less massive doesn't make any mathematical sense for a result that must be a positive number.

    1. Re:Math? by mangu · · Score: 3, Insightful

      How can something be X-times less massive than something else? I can understand half as massive, or 1/10 as massive, but two to ten times less massive doesn't make any mathematical sense for a result that must be a positive number.

      Don't worry, it's only you. Everybody else understood perfectly that they are now estimated to be between 10% and 50% of the former estimate. Or can you imagine any other reasonable interpretation for that?

    2. Re:Math? by Xiph1980 · · Score: 4, Insightful

      two times less massive: 1/2 * m
      ten times less massive: 1/10 * m

      Really, if you want to make it in the world out there, you've gotta get off of your high pedestal, and accept that the scientific world is only a small percentage of the "regular folk" out there. Theoretically, you're right, but practically, noone cares about theory so you're screwed.

      --
      Manuals are your last resort only
    3. Re:Math? by nedlohs · · Score: 4, Insightful

      Welcome to the English language, you will notice that it is not actually a branch of Mathematics.

    4. Re:Math? by Trepidity · · Score: 4, Insightful

      It's not even uncommon language in science, though maybe you'd be more precise when writing a paper. In this context, "times" is understood as colloquial shorthand for "by a factor of", and factors can be either multiplied or divided, depending on whether it's "greater" or "less" by that factor.

      The translation from "two times less massive" to "less massive by a factor of two" is pretty straightforward and easily understood...

    5. Re:Math? by MozeeToby · · Score: 3, Insightful

      The 'ambiguity' is a standard phrasing that has been part of the language for more than 100 years. Language is not math, language is not 100% logical. This argument is equivelent to yelling at someone for saying that they're "as hungry as a horse" because they are incapable of eating as much as a typical horse. It's a stupid and pedantic argument that tries to apply strict logic and mathematical rules to a system (language) that does not follow them.

    6. Re:Math? by mangu · · Score: 3, Interesting

      The translation from "two times less massive" to "less massive by a factor of two" is pretty straightforward and easily understood...

      The real problem happens in the opposite direction. A star that's 200% as massive as the sun is smaller than one that's 150% more massive than the sun, but many people will give the wrong answer if asked.

    7. Re:Math? by Mr_Huber · · Score: 3, Informative

      It's also a difficulty with language. In physics, mass and weight are two separate concepts. We have comparison words for weight: heavier and lighter. But we do not necessarily have the same comparison words for mass. So we're stuck with the English default construct of more massive and less massive. Sure, we could use lighter in this context and hope everyone understands we really are discussing the concept of mass, not gravitational attractive force to the local big rock, but most physicists dislike that imprecision.

  4. The real question is by ArhcAngel · · Score: 5, Funny

    Will MUSE release a followup called "Not So Supermassive - Black Hole"

    --
    "A person is smart. People are dumb, panicky dangerous animals and you know it." - K
  5. Re:Just as I thought... by bunratty · · Score: 4, Insightful

    Certainty in a position gives people a stronger reason not to believe competing ideas. It's basic cognitive dissonance. Let's say I prepared for aliens to visit and destroy the world on a certain day. When that doesn't happen, I can either admit I was wrong or I am uncertain about whether these aliens even exist, or I can confidently believe that the aliens spared us because of our faith. It's easier to confidently believe that AGW is a big hoax than to admit the possibility that we're causing the climate to change. It's easier to believe that evolution is not real if it causes me to question my faith in the existence of God. People will do all kinds of mental gymnastics rather than admit a truth they find emotionally disturbing. Even the lamest excuse will do. The latest is the old "the science isn't settled" when there's the least little bit of uncertainty.

    --
    What a fool believes, he sees, no wise man has the power to reason away.
  6. Things are looking up by Mr_Huber · · Score: 4, Funny

    Well, it's nice to know that something in the Universe now sucks less.

  7. Re:When will we ever learn by c6gunner · · Score: 3, Insightful

    Scientists would do everyone a favor if they dropped the formula "we used to think, but now we know".

    Kinda hard to drop something that's never been used.

    I could have dismissed this as the reporting being at fault, but the abstract ends with "Knowing the rotational velocities, we can derive the central black-hole masses more accurately; they are two to ten times smaller than has been estimated previously."

    Emphasis added. Hope that helps with your parsing problem.