Supermassive Black Holes Not So Big After All 153
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)."
Math? (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.
Re:Math? (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.
I agree. That pet peeve ranks right up there with "I could care less".
Like nails on a chalkboard.
Re:Math? (Score:4, 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?
Re:Math? (Score:5, Insightful)
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.
Re:Just as I thought... (Score:5, Insightful)
Re:Math? (Score:5, Insightful)
Welcome to the English language, you will notice that it is not actually a branch of Mathematics.
Re:Math? (Score:5, 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...
Re:Math? (Score:4, 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.
Re:Math? (Score:0, Insightful)
Re:When will we ever learn (Score:4, 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.