As long as one differentiates between "Fundamentalists" and most other Christians.
Cosmos: A Spacetime Odyssey
- Thread starter Valka D'Ur
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As long as one differentiates between "Fundamentalists" and most other Christians.
They're a minority, for sure. And their bleating is just echo-chamber stuff. I think that the net damage their faith is doing is exponentially dropping. A society apparently can function with a minority of people being willfully wrong on certain scientific learnings.
Aroddo
Emperor
That's right. Christianity ruined Rome.
Lead only gave them an opening.
Carbon dating is so scientifically accurate that we have wood from the future.
Spoiler large image :
And here we see the difference between a scientist and a YEC, when presented with a suspicious result:
Scientist: I wonder what went wrong with that. Let's find out and avoid that in the future.
YEC: Simple application of the method went wrong. Nothing can ever be trusted!
Or in other words: Scientists are interested in the truth, YECs are not.
He didn't say it was. It's only one of a long list of causes that have been tossed around over the years, and there is no one single cause.
timtofly
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Questions: Episode 4
The argument started out that moving bodies do not affect the speed of light. That was the basis for saying that the speed of light was a constant. There was never a mention that light travelling through a medium effects it's speed. Then we are told that a black star (black hole) has such a gravitational mass that light cannot escape it. Is not a dark star an object that effects the speed of light? Does it not stop light but actually "draws" it in which would seem to stop light altogether and light and time actually "stand still" allowing one at the event horizon to see the whole timeline for a split second before going to where no human has gone before? How does light travelling through a medium and being effected by gravity not point out that light speed is not a constant?
We measure time by this constant and we even say that time is relative to gravity. Speed is effected by time and distance. However if light can actually travel faster where gravity is the weakest, and gravity is not uniform, then how can the speed of light be uniform also?
The argument started out that moving bodies do not affect the speed of light. That was the basis for saying that the speed of light was a constant. There was never a mention that light travelling through a medium effects it's speed. Then we are told that a black star (black hole) has such a gravitational mass that light cannot escape it. Is not a dark star an object that effects the speed of light? Does it not stop light but actually "draws" it in which would seem to stop light altogether and light and time actually "stand still" allowing one at the event horizon to see the whole timeline for a split second before going to where no human has gone before? How does light travelling through a medium and being effected by gravity not point out that light speed is not a constant?
We measure time by this constant and we even say that time is relative to gravity. Speed is effected by time and distance. However if light can actually travel faster where gravity is the weakest, and gravity is not uniform, then how can the speed of light be uniform also?
Ziggy Stardust
Absolutely Sane
Light speed is constant in a given medium. Always travels the same speed through vacuum for instance.
A black hole draws in spacetime itself. The closer you get to the center, the faster. So when that speed exceeds the speed of light, light cannot escape anymore since it travels at the speed of light.
A black hole draws in spacetime itself. The closer you get to the center, the faster. So when that speed exceeds the speed of light, light cannot escape anymore since it travels at the speed of light.
timtofly
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Would time, light and even movement through space get slower the closer you get because of the tremendous amount of gravity? If gravity effects the speed of light then light may travel faster than has been observed in space where gravity is negligible?
Gravity doesn't affect light speed. It affects space. No matter where you are and how strong gravity is, you would always measure the same light speed. In a black hole space is warped in such a way that light cannot escape, but the light speed is constant.
The observation that light speed is constant is only really true in vacuum. "Light" in a medium does not travel at the same speed, but in medium "light" is only approximately, but not exactly light. It is a combination of a traveling electromagnetic wave (light) and a traveling wave of atomic excitations.
That's not true. There are a lot of potential factors that can affect light speed in any medium other than vacuum.
Ziggy Stardust
Absolutely Sane
Standing corrected.
I like how they got it down to 30 mph in some sort of crystal.
I like how they got it down to 30 mph in some sort of crystal.
timtofly
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Light has both particle and wave properties. As it travels in wave form, is not that form which is affected by gravity? The constant speed is only relative to the viewer in a given local. Is not this constant upheld even in places that cannot be observed, because the math involved does not show any variance? Does gravity work as a medium or is it a wave form that works side by side with the light wave?
In those experiments, only a small part of the light is actually an electromagnetic wave. Most of it travels as a so called "spin wave" - a wave of atomic excitations. You can go even further and stop the light. in that case, there is no electromagnetic component any more and the light is stored in the medium until you bring the speed of light to a finite value again.
That light is a quantized field is not relevant for its interaction with gravity, because in our current theory of gravity, light does not interact with gravity at all. Instead gravity interacts with space and bends space. Light just goes "straight" in space and if space is bent, light will just follow that.
The fact that the speed of light in vacuum is constant is an observed fact, a measurement. The measurement is relative to a viewer, but the point is, that it is constant for all viewers, no matter where they are and how fast they move. The theory that describes that is built upon that observation, so the formulas do not show any variation, because that is what the theory assumes.
It could be possible that the speed of light is not constant in places where we cannot observe it, for example in a black hole, where we don't really know what is going on. That would require a modification of our current theories. But unless we see a deviation anywhere, there is no reason to assume that the speed of light isn't constant everywhere.
timtofly
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Would not the ability of different environments including the one's carried out by scientist point to the fact that light does not always travel every where in the universe at the same speed? It seems like a constant to us, because in the ordinary daily movement of light that is the speed that it goes. And if that constant were to change it would change the equations that contain the constant "c" ? Is it not true that in certain experiments light can even travel faster than it's known speed?
A new question from episode 6 ( I think). Tyson stated travelling at the speed of light time stands still. Would that make distance not related to time? Time has not changed for the wave of light one is riding on. Thus there is the same point of time no matter where you go in the universe.
On one hand we use light to state the age of the universe, then on the other hand light has no time factor when it moves. It seems time would change even if you were moving at the speed of light.
The last episode (7) seems to get a little unscientific just to prove a single point. The scientist who tested over and over how lead is a very bad thing, in one test proved the earth is 4.6 billion years old? While I appreciate the environmental aspect of saving human lives, we just somehow have to accept with a single test the earth is 4.6 billion years old? I suppose a little faith cannot hurt when it comes to science.
A new question from episode 6 ( I think). Tyson stated travelling at the speed of light time stands still. Would that make distance not related to time? Time has not changed for the wave of light one is riding on. Thus there is the same point of time no matter where you go in the universe.
On one hand we use light to state the age of the universe, then on the other hand light has no time factor when it moves. It seems time would change even if you were moving at the speed of light.
The last episode (7) seems to get a little unscientific just to prove a single point. The scientist who tested over and over how lead is a very bad thing, in one test proved the earth is 4.6 billion years old? While I appreciate the environmental aspect of saving human lives, we just somehow have to accept with a single test the earth is 4.6 billion years old? I suppose a little faith cannot hurt when it comes to science.
Science doesn't rely on a single test. One of the basic things about the scientific method is that the tests/experiments must be repeatable. It's not enough for just one person to perform an experiment or take observations and proclaim that what they saw is THE answer. It has to be verified by others as well.
Ziggy Stardust
Absolutely Sane
Yep, that's exactly how science works. One guy runs a test and comes up with a conclusion. And no one after that is allowed to do that test. We just accept the conclusion of that one test on faith. You nailed it Tim.
I suppose the desire to bring science down to the level of religion is very compelling. After years of trying to get a little understanding across that desire just wipes that all out. I understand the sentiment though. After years and years and years of science coming up with reproducible verifiable results, one might get a little envious when one looks at his own arsenal of understanding things. Faith and religion seem very bleak in the regions where science dwells, so I guess one way of arguing the case against science would be: No you!
I suppose the desire to bring science down to the level of religion is very compelling. After years of trying to get a little understanding across that desire just wipes that all out. I understand the sentiment though. After years and years and years of science coming up with reproducible verifiable results, one might get a little envious when one looks at his own arsenal of understanding things. Faith and religion seem very bleak in the regions where science dwells, so I guess one way of arguing the case against science would be: No you!
No. There is no known way of changing the speed of light in vacuum. That suggests that it is constant everywhere.
yes, the equations would change in some way. And that would alter for example the spectrum of the stars we see. That the spectra look as expected, is another hint that the speed of light cannot change too much in the universe. In fact, it puts a very tight constraint on any potential variations of the speed of light.
This is false. In no experiment the group velocity of light has been observed to exceed the speed of light. There are some experiments that make it look like light has traveled faster than it should, but if you look closely, no energy gets ever transferred faster than light.
If you want to state how much time has passed you need to choose a reference system. I think it is fair to use the earth as the default reference system at state the passage of time for earth. Something traveling near the speed of light might have less time passed, but why should that bother us?
It is not like that test was the only test ever made, nor like the method used was the only method ever used.
So for tonight's (last night's) episode, there's more explanation for how the system for classifying star types was developed, and long-overdue credit is given to the women who undertook that painstaking work. I first read about Henrietta Levitt's work years ago, in a book about star names and their meanings. It was interesting to see how it came about.
From what i read of the new show it seems that i will not watch it.. Too bad cause i was at least curious about the list of astronomers the work of which they presented.
Going by the names in the thread i have to assume that astronomy first appeared in 1066, in a piece of tapestry
Going by the names in the thread i have to assume that astronomy first appeared in 1066, in a piece of tapestry
timtofly
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The show jumps around instead of going in a boring chronological order. I am pretty sure though that they placed it before writing.
I suppose if some one watches without a critical eye, they may make it through most of the episodes without much headache. I watched the first four in one sitting and the last 3 available in the next sitting. I have not watched the 8th one yet.
Watching it on demand though, I can fast forward through the show, but not through the commercials. And they normally remove them after a few weeks, but fox must not let them do it for this show.
I suppose if some one watches without a critical eye, they may make it through most of the episodes without much headache. I watched the first four in one sitting and the last 3 available in the next sitting. I have not watched the 8th one yet.
Watching it on demand though, I can fast forward through the show, but not through the commercials. And they normally remove them after a few weeks, but fox must not let them do it for this show.
