Saturday, August 15, 2015

SN 1995K Is Evidence for An Expanding Universe

28 comments:

Duncan said...

Problems with the SN Ruler?

http://m.pnas.org/content/96/8/4224.full

Duncan said...

Theories in which photons dissipate their energy during travel are excluded as are age-redshift dependencies.

http://arxiv.org/abs/astro-ph/?9605134

So the conclusion is somewhat blinkered.

Duncan said...

https://www.cfa.harvard.edu/supernova/HighZ.html

Edgar Foster said...

Duncan,

1) Any good study will present both sides of a matter. The first link you referenced merely demonstrated that more work remains to be done before we conclude (definitively) that an expanding universe best explains the observations of SN 1995K. As the article concludes:

"But in any case, it seems as if supernova observations finally have made it possible to carry out the program outlined by Sandage (25, 26) to determine the acceleration and the geometry of the universe by observing the distances and redshifts of standard candles."

2) I'm not sure how exclusing certain photon theories makes the conclusion "blinkered." Why were these theories excluded? That would be my first question.

Duncan said...

I am merely responding to the heading of your post - "proof".


occam's broom is applied to the majority of studies & I would have thought that you would understand that complexity is avoided wherever possible (keeping things neat & pigeon holed) to the detriment of true science.

SN studies may be the way to go, because thats what is currently observable but the conclusion made with such small samples (which hardly makes a solid conclusion of being defined as standard candles) and limited knowledge of the properties of light through speculated media forms ( which my subseqent post touches on) can hardly be labeled as "proof".

Suggestive, perhaps.

Edgar Foster said...

Duncan,

Technically, my post said evidence rather than proof. A trial lawyer may enter an exhibit into evidence, but that differs from proof.

I do understand the tendency of science to be parsimonious, but the practice seems beneficial and practical to me. Lest my intent be misunderstood, I offered the information as evidence and not proof per second. I also realize the provisional nature of all such proposals.

Edgar Foster said...

Per se, not per second. Crazy tablet.

Edgar Foster said...

I guess my illustration from jurisprudence for evidence is not a good one. Maybe a better contrast might be a logical proof versus offering evidence that might support some belief or concept without constituting sufficient proof for the belief or concept.

Duncan said...

"I do understand the tendency of science to be parsimonious, but the practice seems beneficial and practical to me." - I am afraid that my scope of experience tells me the opposite.

https://www.youtube.com/watch?v=G0R09YzyuCI

http://ourfiniteworld.com/2011/09/27/drilling-down-tainter-and-patzek-tell-the-energy-complexity-story/

https://www.youtube.com/watch?v=RhgBeT_gkJU

Duncan said...

"the proof of the pudding is in the eating" should be changed to "the proof of the pudding comes a while after the eating".

Edgar Foster said...

Didn't Einstein say that we need to make a matter as simple as possible, but no simpler than that. In other words, avoid being simplistic. And it would seem that this parsimonious approach worked out well for Einstein.

Your links evidently deal with complexity in another sense of the word. My comments about parsimony strictly apply to the scientific method and logical reasoning. In these areas particularly is where I believe that Ockham's "don't multiply entities beyond necessity" principle applies. However, other aspects of life may require a different approach as you suggest.

Duncan said...

To avoid being simplistic you would have to know all the parameters required for a correct conclusion in advance? Which some believe that Einstein did.

Duncan said...

Einstein leading to Oppenheimer makes my point very well as to reductionist science. How to bang rocks together to make fire.

http://www.nybooks.com/articles/archives/1966/mar/17/on-albert-einstein/

Better to be a plumber.

Edgar Foster said...

I'm not sure how anyone--even Einstein--could know all of the parameters required for a correct conclusion in advance. At least, he/she will not know the requisite parameters every time and in all circumstances. For instance, while relativity theory has great predictive and explanatory value, there were times when Einstein seriously erred (e.g., the cosmological constant and quantum physics).

Edgar Foster said...

My aim/argument is not for reductionist science, but I'm just saying that there's a good reason why parsimony is valued and employed in modern science.

Duncan said...

Einstein,

“physical concepts, are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world.”

Edgar Foster said...

But the cosmological constant has been refuted, and Einstein was also wrong about quantum physics.

Duncan said...

"there's a good reason why parsimony is valued and employed in modern science."

That may be the case but I still am at a loss to see why.

http://blog.professorastronomy.com/2009/02/was-einstein-wrong.html

"General relativity's concept of the equivalence of matter and energy (E=mc2) is at the root of our nuclear fission and fusion reactors (and bombs)."

https://www.youtube.com/watch?v=NnMIhxWRGNw

It's still all about the proof of the pudding.

https://www.youtube.com/watch?v=C8xUIncH9t0

Simple answers produce overly simplistic solutions.

Edgar Foster said...

Simplicity does not obviate the proof being in the pudding, nor is a simple approach to a problem necessarily simplistic. Relativity theory is simple in the relevant sense we are discussing, but it's not simplistic.

Edgar Foster said...

If there's a noise in my attic, I see no need to postulate ghosts or gremlins as the source of the noise.

Duncan said...

https://en.wikipedia.org/wiki/Blind_men_and_an_elephant

The conclusions of each individual are fine as long as they are not acted on individually.

https://en.wikipedia.org/wiki/Frame-dragging

If one is only looking at a small part of the elephant the result can only be simplistic.

How these simple (occam's razor) models do not seem to work in practice.

http://bigbang-entanglement.blogspot.co.uk/2006/03/how-small-anomalies-could-influence.html

Edgar Foster said...

I guess we'll have to agree to disagree on this one because I do not equate simple with simplistic, and I only understand Ockham's razor applying to how science is done. There is more than one dimension to the razor, but it partly says that we should not multiply entities beyond necessity. That seems to be a warning about unwarranted assumpted or assumptions that bring undue complexity to an experiment. And I don't find that approach simplistic at all. As mentioned earlier, relativity is simple, but it explains more than the complex theory of Einstein's predecessors. There is virtue in being simple, as we often hear about Jesus' teaching being simple, but true.

Edgar Foster said...

Please see http://math.ucr.edu/home/baez/physics/General/occam.html

Duncan said...

"Nature operates in the shortest way possible." - the simplistic origin with no basis in the reality. We are only just beginning to understand how much we do not know about diversity in the resilience of all life. The reason why 100% conversion efficiency is impossible since it would achieve no resilant purpose.

http://plato.stanford.edu/entries/induction-problem/

We ignore and/or assume the rest of the elephant, what cannot be observed does not matter & human history regarding the applying of science since the "enlightenment" conclusively prooves the point. We assume the cause and assert the effect.

The difference between Torah and law. John 12:49.

Simple but not simplistic.

Edgar Foster said...

I'm not advocating a reductionistic view of ther world. As a theist and one who takes metaphysics seriously, that seems highlu unlikely. All I'm saying is that there are good reasons why science (as we know it today) values simplicity. I also favor not makiing unnecessary assumptions. But making assumptions is an integral part of life. We all do it, and must assume things, in order to do any thinking at all. I emphasize that Einstein's theory of relativity is simpler than Newtonian mechanics, but yet it seems to have greater predictive and explanatory value. And relativity theory is not simplistic.

Duncan said...

Let's just take mass as a sample component.


"One problem in science is that MASS "has" to be given to particles by some, as yet to be found mechanism, so all we have to date is "fields", if this magical giver of mass is not found, then action, reaction must be a product of the fields, thus mass may only have meaning to "life forms"."

Reference https://www.physicsforums.com/threads/is-mass-an-illusion.72042/

Just because we get many expected results from our use of the tool "mass" we are still applying it to something we cannot anywhere near fully define or universally predict. Localised (a limited number of light years - if such exists) phenomena is as far as our experiments can take us.

So it is practice in application but still simplistic.

Edgar Foster said...

I don't consider mass to be a tool; for me, it's a mind-independent reality. One can attempt to theorize mass/matter away (like George Berkeley does) but I find the existence of mass/matter to be the best and simplest account of our phenomenal experience:

"The mass of an object is a fundamental property of the object; a numerical measure of its inertia; a fundamental measure of the amount of matter in the object. Definitions of mass often seem circular because it is such a fundamental quantity that it is hard to define in terms of something else. All mechanical quantities can be defined in terms of mass, length, and time. The usual symbol for mass is m and its SI unit is the kilogram. While the mass is normally considered to be an unchanging property of an object, at speeds approaching the speed of light one must consider the increase in the relativistic mass."

See http://hyperphysics.phy-astr.gsu.edu/hbase/mass.html

There are plenty of things we also can't adequately define, including time and love. Yet we make reasonable assumptions (and stabs) about both, then keep on with the daily affairs of life. And despite the fact that science is obviously limited to the study/analysis of certain phenomena, that doesn't mean that it's necessarily simplistic. As long as science recognizes its limits, I don't have much of a problem with the scientific method. I judge each scientific project on its own merits (as I understand those merits).

Duncan said...

"If you can't measure something, even in principle, then it isn't a subject for physics (or more generally, science)."

But isn't the real question - what are we actively looking to measure & does what we already "think" we know limit what we are looking for?

Tablet typo is a real problem in our conversation - "practice" should have said "practical".

So we agree - practical in application.