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Author Topic:   How do creationists explain stars?
nwr
Member
Posts: 5585
From: Geneva, Illinois
Joined: 08-08-2005


Message 226 of 297 (328871)
07-05-2006 2:24 AM
Reply to: Message 225 by johnfolton
07-05-2006 2:09 AM


Re: Q&A
I found a web page that illustrates group velocities. Perhaps that will help.
This message is a reply to:
 Message 225 by johnfolton, posted 07-05-2006 2:09 AM johnfolton has not yet responded

Percy
Member
Posts: 18594
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


Message 227 of 297 (328898)
07-05-2006 8:17 AM
Reply to: Message 225 by johnfolton
07-05-2006 2:09 AM


Re: Q&A
Hi John,

Be sure to visit Nwr's link and watch those waveforms. The visual picture of the relationship between waves of light and the pulses that contain them is very helpful to understanding what the article is really saying. Here's the link again:

http://physicsweb.org/articles/world/13/9/3

First, it's important not to ignore the places in the article where they tell you in no uncertain terms that light is *not* traveling faster than c. There's this from the second paragraph:

PhysicsWeb article writes:

Nothing can travel faster than light. Despite a recent raft of reports in the media, this statement is as true now as it ever was.

And this:

More importantly, the relativistic notion of simultaneity makes it clear that no information can travel faster than light without throwing all our concepts of cause and effect into disarray. Relativity teaches us that if two space-time events are separated so that they cannot be connected by any signal travelling at c or less, then different observers will disagree as to which of the two events came first. Since most physicists still believe that cause needs to precede effect, we conclude that no information can be transmitted faster than the speed of light.

And this from near the conclusion:

Although relativity emerges unscathed from these experiments, our understanding of exactly which velocities are limited (or not) by c continues to evolve. And even though neither energy nor information is transmitted faster than light in experiments like the one at the NEC, it has already been proposed that the effects may one day be useful in compensating propagation delays in electronic systems.

The article is telling the reader in several different places that the propagation of information cannot exceed c and that relativity has not been invalidated.

The article attempts to make clear what is really happening by saying that it is the motion of an effect and not of an object or light, and it does this with an analogy to the sweeping light beam from a lighthouse:

Nevertheless, velocities greater than c can be observed. Suppose a lighthouse illuminates a distant shore. The rotating lamp moves quite slowly, but the spot on the opposite shore travels at a far greater velocity. If the shore were far enough away, the spot could even move faster than light. However, this moving spot is not a single "thing". Each point along the coastline receives its own spot of light from the lighthouse, and any information travels from the lighthouse at c, rather than along the path of the moving spot. Such phenomena are described as the "motion of effects", and are not forbidden by relativity.

You also quoted this from the article:

What is shocking is that such an effect has been observed for the first time without a great deal of attenuation, amplification or distortion of the pulse. It appears as though energy has, in fact, travelled faster than light.

But you left out the very next sentence:

Of course, this is not the case.

There must be something very appealing about the possibility of superluminal velocities that leads to such frequent misinterpretations of this experiment. Internet discussion boards are often abuzz with excited messages about having just read about successful superluminal light experiments, always followed by attempts at patient explanations about why you shouldn't be investing in faster-than-light communications just yet.

It's even harder to figure out why the experiment has received any attention at all. It's a very boring and obscure effect, and I can only surmise that articles that include phrases like, "Relativity hasn't been overturned just yet, but..." are mere hype, and I can't even guess why they're trying to hype such experiments.

To give you an idea just how boring and even silly this effect is (from the point of view of violating c or causality - I'm not saying the physics itself is boring or silly), here's an example using a long car and a short garage. This isn't a very strong analogy, but it's simple and it gets the point across.

Imagine you have a car that is 15 feet long, and a garage that is only 5 feet long. The garage has doors at both ends, and both doors are open. Let us further say that for some reason we've decided that the car will be determined as having entered the garage when the tail of the car passes through the first door, and as having left the garage when the front of the car passes through the second door. Here's a diagram and some explanation:

 
 
 
 
The front of the car is passing out through the 2nd door, and so the car is leaving the garage, even though it is has not yet entered it.

 
 
 
 
 
 
 
 
 
 
The end of the car is passing in through the 1st door, and so the car is entering the garage, even though it has already left it.

By the conventions we have chosen for how to measure when the car has entered and left the garage, the car appears to leave the garage before it has even entered it. But in the same way that the article states in several different places that light leaving before it enters is not what really happens, the car doesn't really leave the garage before it enters it.

--Percy

Edited by Admin, : Fix image.


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Replies to this message:
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steveb
Inactive Member


Message 228 of 297 (328910)
07-05-2006 9:49 AM


WRT Distance of Stars
IF God Spoke things into existence he could have flung them into space.
The speed of light is not a constant, as has recently been proven.
In anycase the distance to the stars are also very dificult to measure, so there is doubt about the actual distances.
Not that that would make a diference to the original creation, and Gods power.

I see it in the same way when God created Adam he did not create him with one day old bones but with very mature bones that would have carried the weight of the person.

The problem with the big bang that I have is where did all the order and design, not to mention all the material and chemicals come from


Replies to this message:
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RickJB
Member (Idle past 3185 days)
Posts: 917
From: London, UK
Joined: 04-14-2006


Message 229 of 297 (328912)
07-05-2006 9:54 AM
Reply to: Message 228 by steveb
07-05-2006 9:49 AM


Re: WRT Distance of Stars
steveb writes:

The speed of light is not a constant, as has recently been proven.

:rolleyes:

Did you even attempt to read the last couple of posts?


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Percy
Member
Posts: 18594
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


Message 230 of 297 (328931)
07-05-2006 11:20 AM
Reply to: Message 228 by steveb
07-05-2006 9:49 AM


Re: WRT Distance of Stars
Hi Steve, welcome to EvC!

Threads here at EvC are almost always closed after 300 messages, so this thread is about 3/4 done. The arguments you've raised have already been raised and addressed in this thread. With only around 70 posts to go, there is far too little time to begin addressing these issues again from scratch.

I know it's a long thread, but if you start reading around post 150 or so you should still get a good sense of the current state of the discussion.

--Percy


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Coragyps
Member
Posts: 5396
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 231 of 297 (328948)
07-05-2006 12:08 PM
Reply to: Message 228 by steveb
07-05-2006 9:49 AM


Re: WRT Distance of Stars
Hi, new guy!!

In anycase the distance to the stars are also very dificult to measure, so there is doubt about the actual distances.

Ummmm.....no. Not much doubt at all for the nearest few hundred:
http://www.rssd.esa.int/Hipparcos/table361.html

And about 4% uncertainty in the 25,000,000 light-year distance to the galaxy Messier 106. That's not a lot of "doubt."


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SINISTERMINISTER
Inactive Member


Message 232 of 297 (329084)
07-05-2006 9:05 PM


god works in the framework of natural law (ordinarily)
delete

Edited by SINISTERMINISTER, : No reason given.


SINISTERMINISTER
Inactive Member


Message 233 of 297 (329091)
07-05-2006 9:14 PM


God typically works within the frame work of natural law.
On at least one occasion ...nature , perhaps with the help of god the creator, manipulated the speed of light in the early universe, in addition the early universe according to the priests of science was tiny and dense, all factors that could influence the speed and incidentals of c.

; { >

Edited by SINISTERMINISTER, : aol spell check hell


Crue Knight
Inactive Member


Message 234 of 297 (329117)
07-05-2006 10:33 PM
Reply to: Message 1 by carini
02-19-2006 1:47 AM


The Universe and all matter were maturely made
Most visible stars in the night sky are less then 3000 light years away which goes in creationists favor, but what about those stars and galaxies more then 6000 light years away, how are these visible with telescopes? Unless god changed the laws of physics from their current values, how are these visible?

I believe the earth is 13,000 yrs old. (See my thread, Calendar Patriarchs in the Bible Study Forum.)

When God created things, he created them maturely. For ex: Adam and Eve were mature. The animals were mature.
God created the star's light all mature as well. It will be pretty wierd he would create everything maturely exept for the star's light.

Edited by Crue Knight, : No reason given.


This message is a reply to:
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Replies to this message:
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Coragyps
Member
Posts: 5396
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 235 of 297 (329121)
07-05-2006 10:41 PM
Reply to: Message 234 by Crue Knight
07-05-2006 10:33 PM


Re: The Universe and all matter were maturely made
It will be pretty wierd he would create everything maturely exept for the star's light.

No weirder than that he would create light from supernovae that could only have exploded before they were created. Supernova 1987A is 168,000 light years away, by trigonometric measurement. If its explosion's light was created "mature" in your cosmology, it records an event 155,000 years before the universe existed. That is "pretty weird."

Edited by Coragyps, : clarify


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anglagard
Member
Posts: 2199
From: Socorro, New Mexico USA
Joined: 03-18-2006
Member Rating: 6.2


Message 236 of 297 (329139)
07-05-2006 11:16 PM
Reply to: Message 234 by Crue Knight
07-05-2006 10:33 PM


Re: The Universe and all matter were maturely made
When God created things, he created them maturely. For ex: Adam and Eve were mature. The animals were mature.
God created the star's light all mature as well. It will be pretty wierd he would create everything maturely exept for the star's light.

The idea that the universe was created with the false appearance of age is known as Last Thursdayism. Do you have any evidence that the universe was created with the false appearance of age?


This message is a reply to:
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johnfolton 
Suspended Member (Idle past 3786 days)
Posts: 2024
Joined: 12-04-2005


Message 237 of 297 (329331)
07-06-2006 11:46 AM
Reply to: Message 227 by Percy
07-05-2006 8:17 AM


Re: Q&A
I was unable to view nwr links, appears I needed at least upgrade to xp to view. However looking at your garage too me it appears the transmitted pulse of light has left the garage however is the returning incident pulse that is returning to the garage at 300 times reduced speed.

It appears that the light has left the garage but when the returning part of the light wave starts returning its returning in the unamplified state (300 times less speed or 1 fifteeth of the amplified waves) that were initially transmitting outward.

Has light left the garage but then runs into resistance then after 60 *ns* loses its amplification and only then is the incident pulse able to return to the garage.

"If so" then starlight pulse width could be unwinding as it leaves our solar system (solar garage) less to compress the light wave outside the solar garage thus increasing lights speed. However recompressing once it re-enters our solar system (solar garage).

If lights waves are compressed (resistance to light within the solar garages) then light waves should naturally uncompress once star light leaves the solar garages).

Group velocities temporarily seem to be increasing the pulse wave width by force which makes it appear to be leaving the garage before its reaches the garage. Yet in space ***is**** the lack of solar resistance allowing light waves to elongate (increasing lights speed) without a loss in information when it recompresses (expressed as starlight) upon re-entering our solar system?

***article two pulses (the pulse leaving the garage and the secondary pulse returning.)

The meaning of a negative group velocity is illustrated in figure 2. Within the cell, the peak of the pulse travels backwards relative to the direction it is moving in outside the cell. Long before the incident light pulse reaches the cell, two peaks appear at the far end: one travelling away from the cell at c, the other travelling back towards the entrance. This second pulse travels 300 times more slowly and is timed to meet up with the incident peak. The transmitted pulse travelling at c appears to leave the cell some 60 ns before the incident pulse arrives, enough time for it to travel an additional 20 metres.

http://physicsweb.org/articles/world/13/9/3

Edited by johnfolton, : No reason given.

Edited by johnfolton, : To add a question?


This message is a reply to:
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Crue Knight
Inactive Member


Message 238 of 297 (330688)
07-11-2006 12:47 AM
Reply to: Message 236 by anglagard
07-05-2006 11:16 PM


Re: The Universe and all matter were maturely made
The idea that the universe was created with the false appearance of age is known as Last Thursdayism. Do you have any evidence that the universe was created with the false appearance of age?

Was Adam a baby? Was Eve a baby? Were the animals created immaturely?
It seems the Earth's inhabitants were created with a "false" appearance already.


Read "Time Has an End" by, H. Camping for great evdence that the Bible is true and the word of God. You can read it online at www.timehasanend.org
This message is a reply to:
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Percy
Member
Posts: 18594
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


Message 239 of 297 (330698)
07-11-2006 3:14 AM
Reply to: Message 237 by johnfolton
07-06-2006 11:46 AM


Re: Q&A
Sorry for the delay in responding, just now noticed your reply.

However looking at your garage too me it appears the transmitted pulse of light has left the garage however is the returning incident pulse that is returning to the garage at 300 times reduced speed.

The garage analogy is a very weak one. You're reading far too much into it if you're looking for actual correspondences to light pulses. Its only purpose was to point out that you're observing a secondary effect, not an actual sequence of events that indicate superluminal velocities.

I don't think I can add much to what I said before. I again refer you to all the places in the article that make clear that c has not been violated and that relativity is intact. I quoted these in my Message 227.

--Percy


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kinetic2080
Junior Member (Idle past 4431 days)
Posts: 1
Joined: 03-02-2007


Message 240 of 297 (387708)
03-02-2007 4:52 AM
Reply to: Message 9 by Coragyps
02-22-2006 12:06 PM


I read about the distance calculation og stars from wikipedia:

http://en.wikipedia.org/wiki/Parallax

Im just an amateur mathematican (college grade) but I seem to remember that according to Einstein space bends around planetary bodies. Does this influence parallax distance calculations or is it irrelevant? How accurate can you measure distance?

-Kinetic


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