Falsifying a young Universe. (re: Supernova 1987A)

As far as absolute distances in space go, there's at least one that's purely trigonometrically determined at 25,000,000 light years, plus or minus a million. It's to a galaxy called Messier ( pronounced mess-ee-AY, after a French astronomer) 106. The galaxy's nucleus has a ring of gas orbiting it, and we can tell how fast it's turning from the Doppler effect - its light is redshifted on one side and blueshifted on the other. Also, "knots" of radio emission in the ring are moving across our line of sight, and their angular motion was measured over a few years with terrifically accurate radiotelescopes. The combination of angular distance and speed immediately gives distanc traveled by the knots, and thus distance to them by triangulation.I have the paper at home - link tonight when I get there.

Thanks for the reply. I never meant that trigonometry didn't come up with the distance. My point is that the distance then is then translated in light years, then time. So light speed does have a lot to do with it. So, fine, use trig to compute distance. After that, though, we say it is 170,000 years away, as light now travels. Herein is my focus, because we now need to say nothing ever has changed, or will ever change, as regards light to time effects. Yes, I can live with someone saying 'it appears by our limited knowledge, that, because of apparent decay rates in the supernova, light speed was the same at the time of the explosion'. But to use language of such finality seems cocky to me.

quote:

---

Thanks for the reply. I never meant that trigonometry didn't come up with the distance. My point is that the distance then is then translated in light years, then time. So light speed does have a lot to do with it. So, fine, use trig to compute distance. After that, though, we say it is 170,000 years away, as light now travels.

---

We can even do better than that. Remember my picture of the halo around the supernova? Through trigonometry we can calculate the distance between the supernova and the debris that made up the halo. After the supernova exploded, the light from that supernova then illuminated that debris. Since we know how long the light took to get from the supernova to the halo, and we also know the distance between the halo and the supernova, we can then calculate the speed of the light that exited the supernova. Guess what? The calculated speed matches the speed of light on earth. We are able to measure the speed of light in distant space as well as on earth, and that speed does not differ. I'll post the picture again. The supernova is the bright dot in the middle and the bright circle around the supernova is the illuminated debris. Therefore, for the universe to be young there needs to be something in the light path of this supernova that momentarily accelerates light to more than 100,000 times its current speed and then something else has to slow it down to it's regular speed before it reaches earth. Either that or God is showing us light from a star that never existed.

quote:

---

Herein is my focus, because we now need to say nothing ever has changed, or will ever change, as regards light to time effects.

---

No. Now all we need to say is that every piece of evidence we have is consistant with light always having the same speed when it travels through a vacuum. That is a true statement. All theories in science are tentative, and this example is no different. However, to claim that this light is travelling at a different speed is not supported by any evidence and is contradicted by the evidence we do have. The only reason to claim that light travels at different speeds in a vacuum is to conform to a literal reading of Genesis.

quote:

---

You are correct, though, that the equality of light years with the time that has passed since the light left a distant object like a star would no longer hold if light has not always traveled at the speed measured today.

​

There is no evidence that light has ever traveled at a speed different from that measured today.

---

On the other hand, actually, do we have evidence that it always was, and will be the same? Now, I can see this thread, talking about the apparent decay rate at a certain distance would be one limited indication. In a fairly recent experiment in a lab, didn't they change the speed of light (slow it down?) If I remember correctly, I also heard something about people speeding it up, to where it kinda exited the area, before it got there, or something like that? Would it not be safe to say we at least have some evidence that light speed can be changed?

quote:

---

...Our first argument is based on a straightforward observation of pulsars. Pulsars put out flashes at such precise intervals and clarity that only the rotation of a small body can account for it (Chaisson and McMillan, 1993, p.498). Indeed, the more precise pulsars keep much better time than even the atomic clocks on Earth! ..

---

Now we see a statement here, on which a lot is built upon. "That ONLY the rotation of a small body" can account for it. Really? If the Universe were a gigantic, precise creation, with clockwork precision, most of which is beyond our ability to really yet comprehend, would it be surprising that we could even set our little atomic clocks by it!? How can I, with real certainty say ONLY a rotation of planets, like we are familiar with, could possibly account for such things, as a blanket absolute rule, without exception, and upon which we can then proceed to build a whole 'house' of assumptions based on this? Seems to me it is merely projecting a very limited understanding of ours, out into infinity, and, instead of calling it conjecture, calling it a law.

Sort of. When we say "the speed of light is constant" we almost always leave out the "in a vacuum" because we think it goes without saying. The speed of light in a vacuum is constant. Light has been slowed to ridiculously slow speeds in physical media, which says nothing about the speed of light in a vacuum. Light pulses have traveled faster then the speed of light in a vacuum, but that's not quite the same as light traveling faster than the speed of light in a vacuum. I'm not sure I understand that latter fact well enough to explain it. See Fast and slow light made easy or Superluminal and Slow Light Propagation in a Room-Temperature Solid (requires free rgistration). No. It would not be safe. We have no such evidence.

The apparent reduction in the speed of light in physical media such as glass and water is because the light is absorbed and retransmitted. This process takes place at different rates for different frequencies (and therefore different energies) of light, which also explains why different frequencies of light appear to have different speeds within the media. When traveling from its transmission by one atom to its reception by another, light always travels at the speed of light. Another way to think about the speed of light is that its the speed at which the effects of physical phenomena are transmitted throughout space.One thought experiment makes this last fact especially apparent. Imagine you wanted instantaneous communications with the moon, instead of having to wait 1.3 seconds for radio communications. You construct a rigid steel rod from the earth to the moon. When you push your end of the rod on earth, the other end of the rod on the moon moves instaneously. Voila! Instant communication! Except that it's not. It takes the fact that the end of the rod on earth has been pushed 1.3 seconds to reach the moon. And probably longer, because our rigid rod isn't actually perfectly rigid.--Percy

quote:

---

Light has been slowed to ridiculously slow speeds in physical media, which says nothing about the speed of light in a vacuum

---

OK so it would be more or less impossible for forces cosmic to have substansially altered the speed in the vacuum of space. So the kind of light we have now just isn't really up to the job. They talk about some leftover 'light' "This ancient light, which pervades the sky in all directions, is now a frigid minus 270.45 Celsius. Even so, it contains tiny - one part in 100,000 - deviations in its temperature profile that theory suggests reflect subtle density differences in the matter of the early Universe" (BBC NEWS | Science/Nature | Sky surveys reveal cosmic ripples)
"Suggests" is a funny word. I guess, in other words,near it's creation, there were some things very different back then in our universe. We used to laugh st the "flat earth" people in school, who actually claimed to believe the earth was flat. In today's news, it appears that science is flatly stating now the universe is FLAT!
"The Sloan group says its work has given the clearest demonstration yet that the geometry of the Universe is "flat". " Ha, I guess that's progress!

has different meaning. relates to ability of expansion inertia vs gravitational forcesWMAP Cosmology 101: Shape of the Universe

---

we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

"This means the usual rules of Euclidean geometry taught in schools apply all over the cosmos: straight lines can be extended to infinity and the angles of a triangle add up to 180 degrees, etc. " (from previous link I gave)
Yeah, but I still find it humorous they now say the universe is FLAT.
The fact that God stretched it out like a curtain, we already knew long ago!!Ha {Ps 104:2 Who coverest thyself with light as with a garment: who stretchest out the heavens like a curtain) Call it "expansion" if you like!

Reference for the galaxy distance above is Herrnstein, et al., Nature, v 400, pp 539-541, (1999). And, like most professional astronomers talking of distance, they never say "light year." The parsec is the real unit of distance in astronomy - 7.2 megaparsecs in this case.

I think the term "flat" is very misleading in this regard - it is a purely mathematical construct and does not bear on reality. Even if it wasn't "flat" the euclidean geopmetry would still hold until you got to cosmic levels, and we already have problems with that level (dark energy now in addition to dark matter ....) really? from what scientific source was this published?or are you just presuming much on an appearance of similarity ... last I looked curtains were rarely flat ... much more like 'branes.The Big Bang: What Really Happened at Our Universe's Birth? | Space

---

we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}Edited by RAZD, : bbcode

quote:

---

... last I looked curtains were rarely flat ... much more like 'branes

---

No I don't think secular science is entirely braneless! Anyhow, really, it would depend on the type of curtain, and how much it was stretched! The scientific source? Right from the Great Scientist Himself!

quote:

---

A parsec is defined as the distance from the Sun which would result in a parallax of 1 second of arc as seen from Earth,
[formula was here, but wouldn't cut & paste]
where ly is a light-year. The word "parsec" is an abbreviation and contraction of the phrase "parallax second."

---

(Parsec -- from Eric Weisstein's World of Astronomy)
So, yes parsecs are the 'main squeeze', but notice how inexerably interwoven with time even these units are! (seconds-light years). Also we would need to note that more often than not it is light years that are most often used for us common men.

Not "second" as in "1/60th of a minute", "second" as in "1/60th of a degree."