Real Science Friday: The Best Astronomy DVD Ever Made

[Stripe]

Stripe said:OEJ responded:Nope, gravity is less there.Only true if you are external to the object generating the gravity. You get heavier the closer you get to the surface of the earth. But once you start descending into the earth itself, even though you are approaching its center of gravity, you are actually getting lighter. (At the center of the earth, you would be weightless, even though you would have a gazillion tons of pressure on you from the rock above you.) Similarly, you are within, not external to, the universe. If the universe has a center of gravity, that is where the gravitational pull would be equal in every direction (adding up to zero net gravity at that point.).

hmmm... That's a good point. But what about gravity's effect on light. Does it work in the same manner with light as it does with people?

I agree that this (preview) of the DVD seems to rely on culling unsolved questions in solar system formation and then saying that “Astrophysicists don’t understand this, therefore God did it.” What a perfect way to suggest that rather than trying to understand something not yet mastered, that we throw up our hands and declare it in the province of theology?

Yet even if your assessment were correct it would be no answer to the challenges to evolutionary astronomy raised.

 

[Tyrathca]

Yet even if your assessment were correct it would be no answer to the challenges to evolutionary astronomy raised.

Which is why no one is claiming that there is a "Theory of Solar System Evolution". Besides the raising of problems with the science would be no answer for the challenge of promoting creationism.

 

[One Eyed Jack]

Only true if you are external to the object generating the gravity. You get heavier the closer you get to the surface of the earth. But once you start descending into the earth itself, even though you are approaching its center of gravity, you are actually getting lighter. (At the center of the earth, you would be weightless, even though you would have a gazillion tons of pressure on you from the rock above you.)

Similarly, you are within, not external to, the universe. If the universe has a center of gravity, that is where the gravitational pull would be equal in every direction (adding up to zero net gravity at that point.).

Thanks. I felt bad for holding out on Stripe, but I just didn't have the patience to explain it in much detail. I reckon that's something I ought to work on.

hmmm... That's a good point. But what about gravity's effect on light. Does it work in the same manner with light as it does with people?

As for light itself -- that's governed by special relativity. It doesn't experience time. Gravity might have an effect on the frame of reference, but light is going to be going at light speed in whatever frame of reference that might be. Basically, no matter how fast or slow time is running in a given frame of reference, light is moving at around 300,000 km/s.

 

[Stripe]

Thanks. I felt bad for holding out on Stripe, but I just didn't have the patience to explain it in much detail. I reckon that's something I ought to work on.As for light itself -- that's governed by special relativity. It doesn't experience time.

Something to ponder.

 

[Ask Mr. Religion]

light is moving at around 300,000 km/s.

Or, roughly speaking, about 11 inches per nanosecond.

AMR

 

[DavisBJ]

Yet even if your assessment were correct it would be no answer to the challenges to evolutionary astronomy raised.

I agree. But if you require no holes in the knowledge of a subject before you will accept it (at least provisionally), then honesty would require you to never trust anything electronic, nor to fly in an airplane, nor to accept that the heat from the sun is from thermonuclear reactions. New studies frequently fill in gaps in our knowledge of fields we tend to accept without question.

We can posit, ala Psarris, that since aerodynamic airflow is still being studied, that it is preferable to accept that God carries airplanes by his will.

Maybe we should attribute the source of the sun’s heat to God’s power, and give up on the hopeless quest of thinking that we will ever be able to reach into the center of the sun and see that hydrogen is really fusing into helium.

No one has ever seen a single electron, nor will they ever do so in the way we see objects around us. Lacking that, perhaps Intel should abandon its efforts to use atomic theory in the design of ever faster and smaller devices. Give the credit for their operation to God.

 

[Stripe]

I agree. But if you require no holes in the knowledge of a subject before you will accept it (at least provisionally), then honesty would require you to never trust anything electronic, nor to fly in an airplane, nor to accept that the heat from the sun is from thermonuclear reactions. New studies frequently fill in gaps in our knowledge of fields we tend to accept without question. We can posit, ala Psarris, that since aerodynamic airflow is still being studied, that it is preferable to accept that God carries airplanes by his will. Maybe we should attribute the source of the sun’s heat to God’s power, and give up on the hopeless quest of thinking that we will ever be able to reach into the center of the sun and see that hydrogen is really fusing into helium. No one has ever seen a single electron, nor will they ever do so in the way we see objects around us. Lacking that, perhaps Intel should abandon its efforts to use atomic theory in the design of ever faster and smaller devices. Give the credit for their operation to God.

Sure, you could do all that. But there is a clear distinction between all these things and the things God has clearly laid out in Genesis. We have a foundation and a rational reason to test the idea that the solar system is but a few thousand years old. We have no reason to believe God holds each airplane in the sky.

 

[Granite]

As in the earth is 6000 years old, god created all in 6 days, took a breather for one, got angry at eveyone but Noah and killed all with a flood (even little babies), dinosaurs and men lived at the same time, all were vegetarians until the Fall...that truth?

I suspect that about thirty years from now people will shake their heads and wonder how on earth folks could actually believe this nonsense. Creationism will still exist, but it's going to be taken even less seriously than it is now.

 

[Stripe]

And in thirty years granite might still exist. :think:

 

[Jukia]

I suspect that about thirty years from now people will shake their heads and wonder how on earth folks could actually believe this nonsense. Creationism will still exist, but it's going to be taken even less seriously than it is now.

I wish I had your optimism, see for example Gov. Perry's Prayer Day.
"The country has major economic issues, I got nothing, lets see if the Magic Sky Man can supply some ideas. And I can get more votes along the way and maybe I can get elected President."

Hard to decide which is worse, the pandering or the ignorance.

 

[Granite]

I wish I had your optimism, see for example Gov. Perry's Prayer Day.
"The country has major economic issues, I got nothing, lets see if the Magic Sky Man can supply some ideas. And I can get more votes along the way and maybe I can get elected President."

Hard to decide which is worse, the pandering or the ignorance.

Actually in Perry's case I think he actually believes it. So it's not pandering, it's just rot gut ignorance...

I'll put it this way: I can't see creationism gaining any traction over the next few decades. And I can't see the so-called Millenial Generation--which has been less religious, more tolerant, and generally more world-wise than its predecessors--seriously embracing creationism. And the Genesis story will of course still be taught literally by an increasingly fringe evangelical movement.

Maybe I am being too optimistic.:think:

 

[DavisBJ]

Sure, you could do all that. But there is a clear distinction between all these things and the things God has clearly laid out in Genesis. We have a foundation and a rational reason to test the idea that the solar system is but a few thousand years old. We have no reason to believe God holds each airplane in the sky.

Since I am not a believer in your God or the Holy Book you speak of, what is said in Genesis is no more relevant than any other religious creation fable.

 

[Stripe]

Since I am not a believer in your God or the Holy Book you speak of, what is said in Genesis is no more relevant than any other religious creation fable.

And since reality is independent of what you believe I am justified in presuming the truth of what I believe and testing it's veracity.

 

[Stripe]

What if light is affected by gravity in a different manner from rocks and stuff? A rock in the center of the Earth feels equal net pull in every direction rendering it weightless, but perhaps light is affected differently. Perhaps light speed is not affected in the same fashion. Perhaps light responds solely to the total mass in close proximity such that light (hypothetically) traveling through the center of the Sun is more affected the light passing through the center of the Earth.

Is that a reasonable or testable idea?

 

[DavisBJ]

And since reality is independent of what you believe I am justified in presuming the truth of what I believe and testing it's veracity.

Yes, just as people whose theology gives them reason to believe the earth is sitting on top of a tower of turtles might want to investigate that idea. (No apostrophe in “it’s” when used to indicate possession. The apostrophe makes it into a contraction for “it is”.)

What if light is affected by gravity in a different manner from rocks and stuff? A rock in the center of the Earth feels equal net pull in every direction rendering it weightless, but perhaps light is affected differently. Perhaps light speed is not affected in the same fashion. Perhaps light responds solely to the total mass in close proximity such that light (hypothetically) traveling through the center of the Sun is more affected the light passing through the center of the Earth.

Is that a reasonable or testable idea?

I tend to shy away from spending much time scientifically analyzing most ideas, like yours or the turtle one, that are inspired by one’s religious leanings. There is too much real science, unfettered by theological dogma, that I need to allocate my time to.

 

[Frayed Knot]

Actually in Perry's case I think he actually believes it. So it's not pandering, it's just rot gut ignorance...

I agree that Perry actually believes in the power of prayer, but it's still pandering. He's not holding the giant Prayer Day in a football stadium because he thinks that's the best way to solve problems; it's the public demonstration of his piety that he's after.

And the Genesis story will of course still be taught literally by an increasingly fringe evangelical movement.

I agree with you completely.

Perhaps light responds solely to the total mass in close proximity such that light (hypothetically) traveling through the center of the Sun is more affected the light passing through the center of the Earth.

Is that a reasonable or testable idea?

It's not testable in that form - you would have to make a prediction if this were true. However, every measurement that's ever been made is consistent with the idea that gravity bends light just like it would bend the path of any other object.

 

[Stripe]

It's not testable in that form - you would have to make a prediction if this were true.

:dizzy: So it is testable, right?

However, every measurement that's ever been made is consistent with the idea that gravity bends light just like it would bend the path of any other object.

Sure. But doesn't gravity also affect the speed of light?

 

[Flipper]

:dizzy: So it is testable, right?Sure. But doesn't gravity also affect the speed of light?

No, but it bends the path along which light travels (at the appropriate speed for the medium it is traveling through).

 

[Stripe]

Really?

Is the time delay because of extra distance travelled?

 

[Frayed Knot]

Really?

Is the time delay because of extra distance travelled?

No, it's because of time dilation. Light always moves the same speed, but time slows down in a gravity well.