Supernova Casts Doubt on "Standard Candle"

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."

Comments

Gravity Lensing?

[RyanFenton]

Could this be an effect of gravity of surrounding galaxies lensing the light from a 'normal' large star in our direction and just appearing brighter?

Ryan Fenton

The universe will out

[Oligonicella]

Models are just that, models. Change them when the universe shoves reality down your throat. Far too many people think that math defines the universe instead of describing it.

Re:The universe will out

[saider]

That the area of a triangle inscribed in a circle is equal to the product of its three sides divided by four times the circles radius is a physical fact...

Only for perfectly flat space. In reality, all space is curved even if by just a little bit.

We generally discover that what we believe to be a fundamental truth is often dependant on assumptions that we are not aware of. This is where brilliant minds discover more about our world by exposing these hidden assumptions.

Also, we tend to aggregate things for convenience. But the universe does not concern itself with such things. To the universe, 2 apples + 3 apples is simply a lot of quantum particles going about their business. We may have simplified things to 2+3, but that is not what it really is. 2+3 works for most cases, but there will be edges where the simpler math breaks down and if you do not realize that you are dealing with quantum particles instead of a few apples, you may become very frustrated.

Re:The universe will out

[maynard]

Furthermore, how is it that we can "prediscover" phenomena? We develop a model to describe existing data, and whoops!, there's another phenomenon implicit in our model, and sure enough when we look for it in reality, there it is!

I suspect this is like our response to red traffic lights. We remember the annoyance of having to stop, but rarely remember all the times we sail through a green light. Often, people will complain about 'bad luck' with red lights as a result. But the reality is that the red lights aren't directing their stopping power at you - per se.

In the same vein, there are many, many, many inaccurate predictions made in science that experiment refutes. These predictions often have a mathematical basis. So, I'm arguing that you're forgetting about all the many predictions that turn out false in order to focus on those that turn out true (a sort of reverse of the red light phenomena).

Re:The observational evidence is surprisingly scan

[StupendousMan]

These Type 1a Supernova are used as one step on the distance ladder, correct?

Type Ia supernovae are indeed one of the last rungs on the distance ladder; they can be used to estimate distances to very distant galaxies.

So if we no longer believe they all have the same brightness, that means the distance we have on record for many objects is now wrong?

No, that's an overstatement. Type Ia supernovae are one of several different indicators used to estimate distances to very distant galaxies -- not the only one. _If_ we suddenly thought that the luminosity of _all_ Type Ia supernovae was significantly higher, _then_ we would have to re-examine the agreement between distances derived from Type Ia supernovae and other methods. The net effect might be a slight shift in the value of the Hubble constant, which is used to estimate distances to really, really distant objects.

However, if only 1 in 100 or fewer Type Ia supernovae are more luminous than expected, it won't make any significant difference in studies which use lots of supernovae.