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Supernova Casts Doubt on "Standard Candle"

Posted by ryuzaki0 on from the chandrasekhar's-the-limit dept.

Krishna Dagli writes, "A supernova more than twice as bright as others of its type has been observed, suggesting it arose from a star that managed to grow more massive than theoretically thought possible. The observation suggests that Type 1a supernovae may not be 'standard candles' — all having the same intrinsic luminosity — as previously thought. This could affect their use as probes of dark energy, the mysterious force causing the expansion of the universe to accelerate."

3 of 132 comments (clear)

  1. Re:The universe will out by rocketman768 · · Score: 5, Interesting

    I think you are exactly right. I am a mathematician. People should understand that all of mathematics is an abstract concept created by humans. Why does 2+3 = 5? Because we said it does...not because it is universally true. Sometimes (in the case of 'models'), we put some math together to attempt to explain what we see. As we discover new behaviors in whatever system we're looking at, we have to change the math. So, this article is about one of those instances.

  2. This is a GOOD thing.... by trip11 · · Score: 5, Interesting
    ...as supernova are not well understood. First off I am not an astrophysicist, though I am a high energy physicist (and have taken some astro classes). One thing that has been discussed in nuclear classes I have taken is how little we understand just how a supernova functions at the atomic level. The number of competing effects going on during the collapse of a star is just amazing. You have gravitational pull, thermal pressure, rotational 'pressure', electromagnetic forces in a regular star. Now you start to collapse the star and you have to add in the transition of millions of individual nuclei becoming in effect one large nucleous as they all mearge. (not to mention the energy output from this). In effect the strong force comes into play along with the standard EM and gravitational forces. It gets much more complicated than that, but it has been several years since those classes.

    So why do I think this is a 'good thing'? As the article speculates, it is likely that this supernova was different because of some rotational process or perhaps colliding stars, or some other exotic combination. This is exactly the sort of process that can be used as a test of supernova models to see how well they do. Over all I find this a very exciting observation and hopefully it produces more new science!

  3. Re:The universe will out by KutuluWare · · Score: 5, Interesting

    I think his point would be more accurately expressed as this:

    "Why is 2 + 3 = 5?"

    Because the arbitrary definitions which we assigned to the symbols 2, 3, 5, +, and = happen to represent real-world concepts that exhibit the behavior that 2 + 3 = 5, and not because there is any abstract universal rule that "2 + 3 = 5" and we simply need to find real-world behavior to prove it. That is, the real-world behavior has always existed, but the mathematical language used to express it was invented by us and assigned to those behaviors specifically to make the mathematics true.

    (Or something, it's early.)

    --K