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Messages - Hortensius

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1
Flat Earth Debate / Re: The Moon does not appear flat
« on: September 16, 2010, 07:02:45 PM »
LMAO.. Is this your supporting evidence for a moon that shines under it's own light? LOL. Clearly you are playing for antiquity here. And let me guess, you are one of those magic anti-moon fans.  ::) BTW (a bit off topic), do you know how parallax is correctly done? As in the use of Radar to determine what the correct distance of the moon from Earth is. And I am hardly making a fool out of myself here. Also, do you understand lambert's law when considering the moon or even a full moon, or the presumed flatness appearance of the moon? I would hope those who read the OP would understand this law and why the moon for the most part is considered Non-Lambertian.

I'm not a Flat Earth proponent, Einstein. Where did you get that prejudice from? And you don't have to teach me about parallax mate. I happen to know all about it, and it has nothing to do with radar. You are confusing two methods of determining the distance to the moon... Your level in Astrophysics is not sufficient to teach me, stop making a fool of yourself.

I tell ya what, you can feel free to lay down your evidence that validates the moon shines by it's own power lol.

I didn't give you the link to that astrophysics book for nothing mate. Each object radiates its own thermal light, and so does the Moon. If you want to understand how that works, I suggest you order and study the book.

2
Flat Earth Debate / Re: The Moon does not appear flat
« on: September 15, 2010, 10:04:26 PM »
I believe in a disc shaped earth, but its very obvious from my high powered telescope that the moon craters have shadows. I dont see any shadows on the sun.

What make more sense is that the sun shines a floodlight beam that creates the phases of the moon and also causes our days and nights.

That is by definition the difference between something that has an albedo vs something that produces it's own light.  However, the sun isn't a disk or flashlight for obvious reasons.


Something with an albedo can produce its own light also. In fact every known object in the universe with an albedo produces its own (thermal) light. And the sun has an albedo too.

Please try again. It might help you to understand by actually knowing what an Albedo is:

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

And the moon is clearly reflecting sunlight.

If you think the Sun has no reflectivity you are wrong. And if you think that the moon does not radiate by itself (apart from reflecting sunlight), you are also wrong. What is your level in Astrophysics?

If you want to understand more about what you're talking about: http://www.amazon.com/Radiative-Processes-Astrophysics-George-Rybicki/dp/0471827592

Wow, you really didn't comprehend the argument did you.. The sun reflecting it's own light is not the problem son. You can take the time stare at the sun and tell me if you see a crater, or any land features. Hell, turn a flashlight on and flash it in someones face and ask them if they can see any scratches or lens textures. If you want to get technical, Stars would have an Albedo of 100 (which is why most consider them without an albedo since they are the producers or sources of light). You comeback when you fully grasp the context of my posts above ;) And if you read that book, it will concur with the links I provided you. And I strongly suggest you learn how to measure the angle of the moon phases in accordance to the position of the sun.






You didn't answer my question about your level in astrophysics, but your answer speaks for itself more than you think. Don't try to outrun me on the astrophysics department mate, you're making a fool of yourself...

3
Flat Earth Debate / Re: The Moon does not appear flat
« on: September 14, 2010, 10:47:28 PM »
I believe in a disc shaped earth, but its very obvious from my high powered telescope that the moon craters have shadows. I dont see any shadows on the sun.

What make more sense is that the sun shines a floodlight beam that creates the phases of the moon and also causes our days and nights.

That is by definition the difference between something that has an albedo vs something that produces it's own light.  However, the sun isn't a disk or flashlight for obvious reasons.


Something with an albedo can produce its own light also. In fact every known object in the universe with an albedo produces its own (thermal) light. And the sun has an albedo too.

Please try again. It might help you to understand by actually knowing what an Albedo is:

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

And the moon is clearly reflecting sunlight.

If you think the Sun has no reflectivity you are wrong. And if you think that the moon does not radiate by itself (apart from reflecting sunlight), you are also wrong. What is your level in Astrophysics?

If you want to understand more about what you're talking about: http://www.amazon.com/Radiative-Processes-Astrophysics-George-Rybicki/dp/0471827592

4
Flat Earth Debate / Re: The Moon does not appear flat
« on: September 14, 2010, 07:17:57 PM »
I believe in a disc shaped earth, but its very obvious from my high powered telescope that the moon craters have shadows. I dont see any shadows on the sun.

What make more sense is that the sun shines a floodlight beam that creates the phases of the moon and also causes our days and nights.

That is by definition the difference between something that has an albedo vs something that produces it's own light.  However, the sun isn't a disk or flashlight for obvious reasons.

Something with an albedo can produce its own light also. In fact every known object in the universe with an albedo produces its own (thermal) light. And the sun has an albedo too.

5
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 14, 2010, 07:12:22 PM »
Haven't been here in a while so I'm forced to skim a lot of threads, but it looks like Olbers' paradox assumes space between stars to be a perfect vacuum.
As soon as I read the OP I thought, "shit like space dust and gravitational fields would interrupt paths of light". Did I miss something?
But wouldn't the space dust warm up to the same temperature of the stars over time?

The "paradox" applies to present day observations...
Are you suggesting that the estimated age of the universe is incorrect, or that there has already been enough time for 'space' to warm up?  ???

Quote
Even if a line of sight terminates at a dust granule, it would be just as bright as a star's surface.
Why?

Space has had enough time to warm up indeed, in fact the temperature of 'space' is (on average) in perfect thermal balance with the radiation field of the universe. And if the sky was filled with stars, individual dust grains would warm up very quickly until thermal balance with the background radiation, which means that it would have the same temperature (and therefore the same brightness) as the average star. So dust doesn't do the trick.
What you just said here is that EVERYTHING IN THE UNIVERSE should be as hot as stars. Notice how that doesn't work?

If the sky was completely filled with stars. In that case indeed EVERYTHING would be as hot as the stars. We know that the sky is NOT completely filled with stars, and therefore not everything is as hot as stars.

6
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 14, 2010, 07:06:57 PM »
Where did you get this crap from?

I'm not sure what you're asking me.

Dark matter? Or its uniform distribution about galaxies? Or something else?

So much anger...

First, what has dark matter to do with the paradox?
Second, where did you get the idea from that it is uniformly distributed?

7
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 14, 2010, 07:00:26 PM »
And distant stars are dimmer due to 2 effects. 1. The intensity of light falls of as 1/(distance of the star)2. And 2. The intensity of visual light of stars falls of because their radiation is absorbed by colder dustgrains along the line of sight.
Ah, you see this was all I was looking for. An admission that colder particle clouds exist and absorb light.

Yes, and the dust particles are cold because there are not enough stars on the sky to heat them. So sure, cold dust absorbs visible light and emits at infrared wavelengths (according to its temperature). If there were more stars on the sky the dust would be hotter. And eventually if the sky was filled with stars, the dust would have the same temperature as the stars and would start emitting the same light. So in a universe with a star-filled sky, the dust is hot and it is therefore impossible that there is a net absorption of light by the dust.

8
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 14, 2010, 01:03:53 AM »
Your intuition tells you wrong. Thermal radiation is virtually independent of the composition of a dust grain.
If composition of the heated material has no effect than wouldn't a graph of the luminosity vs. temperature of stars be a straight line?
And I'd bet that space dust is less similar than different stars are since they aren't undergoing nuclear fusion. If you have any sources that can clarify this, I'd appreciate it.

Actually, I should have asked for sources that everything is the same temperature too. I find it hard to believe that all clouds of interstellar matter is the same temperature.

EDIT:

Hmm, you pushed me to doing actually work.

Well, a brief search reveals the cooling mechanisms of interstellar matter and a temperature table.

^^^
Keep in mind that small stars have surface temps of a few thousand K.

Ofcourse composition of the material has some effect, but for stars and dust the effect is very small.

Luminosity is proportional to (temperature)4, so no straight line, instead a doubling of temperature leads to an increase of luminosity of a factor 16. And stars and dust are actually very similar when it comes to thermal radiation. When you're looking at a star, you're only looking at its surface which is heated by internal nuclear fusion, you won't see the fusion itself.

Here's a link: http://en.wikipedia.org/wiki/Black_body. It's about blackbodies. Blackbodies are theoretical, idealized objects, but stars and dustgrains actually resemble blackbodies very closely...

9
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 13, 2010, 08:22:56 PM »
[...]which means that it would have the same temperature (and therefore the same brightness) as the average star. So dust doesn't do the trick.
Intuition tells me that temperature doesn't imply equal brightness unless the material is the same composition.
Anyways, not only does dust scatter light (like holding a piece of paper in front of a light bulb), but if you are suggesting they don't absorb a small degree of light, why do you think all the more distant stars are comparably dimmer?  ???

Your intuition tells you wrong. Thermal radiation is virtually independent of the composition of a dust grain.

And I'm not suggesting that dust only scatters light, on the contrary, dust absorbs about 90% of infalling light. For each foton that a dust particle absorbs, it heats up a little and emits thermal fotons according to its own temperature. But if the particle is colder than the background radiation, the amount of energy (and therefore heat) that is lost by emitting thermal photons is always smaller than the amount of heat that it receives from the background radiation. Therefore, the dust grain will heat up until it eventually reaches the same temperature as the background radiation.

And distant stars are dimmer due to 2 effects. 1. The intensity of light falls of as 1/(distance of the star)2. And 2. The intensity of visual light of stars falls of because their radiation is absorbed by colder dustgrains along the line of sight.

10
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 13, 2010, 04:25:25 PM »
Yes, but a non-infinite universe means non-infinite stars, which means plenty of empty space in the sky. A finite universe cannot hold an infinite amount of stars.

You would still have to see an edge somewhere, which in not observed; the universe on large scales appears isotropic (same in all directions) and homogeneous (evenly distributed). Finite universe is not a correct explanation.

11
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 13, 2010, 04:20:54 PM »
Did I miss something?

No.

There's also a lot of dark matter which appears to be uniformly distributed about galaxies which would goof things up a bit.

Where did you get this crap from?

12
Technology, Science & Alt Science / Re: Olbers' paradox
« on: September 13, 2010, 04:18:43 PM »
Haven't been here in a while so I'm forced to skim a lot of threads, but it looks like Olbers' paradox assumes space between stars to be a perfect vacuum.
As soon as I read the OP I thought, "shit like space dust and gravitational fields would interrupt paths of light". Did I miss something?
But wouldn't the space dust warm up to the same temperature of the stars over time?

The "paradox" applies to present day observations...
Are you suggesting that the estimated age of the universe is incorrect, or that there has already been enough time for 'space' to warm up?  ???

Quote
Even if a line of sight terminates at a dust granule, it would be just as bright as a star's surface.
Why?

Space has had enough time to warm up indeed, in fact the temperature of 'space' is (on average) in perfect thermal balance with the radiation field of the universe. And if the sky was filled with stars, individual dust grains would warm up very quickly until thermal balance with the background radiation, which means that it would have the same temperature (and therefore the same brightness) as the average star. So dust doesn't do the trick.

13
Flat Earth Q&A / Re: Question to Infinite Plane Believers
« on: August 30, 2010, 12:02:01 AM »
This is a question specifically directed to Infinite Plane Believers, is it not?

He succesfully answered the question by copy-pasting my argument. Nothing wrong with that...
I believe that point is that the OP asked FEers to respond, not REers. I do appreciate though, and often even myself, try to answer these type of questions if and only if I've seen an FEer answer it.

Sure, but I think it should be a correct question. Not one that is explicitly based on a wrong argument.
It's kind of pointless to have two blind guys discuss the beauty of a flower, if you see what I mean...

14
Flat Earth Q&A / Re: Question to Infinite Plane Believers
« on: August 29, 2010, 11:53:13 PM »
This is a question specifically directed to Infinite Plane Believers, is it not?

He succesfully answered the question by copy-pasting my argument. Nothing wrong with that...

15
Flat Earth Q&A / Re: FE model support
« on: August 29, 2010, 11:46:10 PM »
ITT: Hortensius wins and Username's model is possible?

Nah, what about: Hortensius wins and Username's model is gravitationally unstable...

What are the causes of Earthquakes in Username's model? I recall in some models there aren't any tectonic plates.

Don't know, but for my argument it doesn't really matter what the causes are... And plausible is certainly not the right word...

If I remember you said that earthquakes could make it unstable, but didn't give any further reasons. I also couldn't find those calculations you said you would make.  :(

By now I have made the calculation, but it is far too lengthy and technical to post on this forum. I have shown Username how to reproduce it in a private message and I have given him some literature so that he can do the calculation for himself. So far he hasn't finished it presumably, and I don't expect him to because it involves some advanced physics...

Even without the calculations, (I going to assume they are correct) for what reasons would an earthquake make his model unstable?

Eartquakes, most earthquakes, disturb the gravitational field. And it turns out that only a slight perturbation of the gravitational field leads to instability, or collapse. The stability of an infinite massive slab is comparable to the stability of a huge ball on top of a sharp mountain; if you touch the ball softly it will start to fall...

The nice thing of an infinite plane which is in rest (no earthquake or anything of that sort) is that there is no horizontal component of the gravitational force; gravity is pulling strictly downward. But if you start shaking it, at some places there will be slightly more mass and there will therefore be a slightly stronger gravitational force which will attract the surrounding mass slightly stronger than average. This is the soft push that will lead to collapse.

The only thing that will stabilize a flat earth a little bit is the solid crust. But as you probably know, in reality strong earthquakes can sometimes be strong enough to crack the earth's crust locally. If this would happen on an infinite flat earth, it would simply collapse.

16
Flat Earth Q&A / Re: FE model support
« on: August 29, 2010, 09:39:47 PM »
ITT: Hortensius wins and Username's model is possible?

Nah, what about: Hortensius wins and Username's model is gravitationally unstable...

What are the causes of Earthquakes in Username's model? I recall in some models there aren't any tectonic plates.

Don't know, but for my argument it doesn't really matter what the causes are... And plausible is certainly not the right word...

If I remember you said that earthquakes could make it unstable, but didn't give any further reasons. I also couldn't find those calculations you said you would make.  :(

By now I have made the calculation, but it is far too lengthy and technical to post on this forum. I have shown Username how to reproduce it in a private message and I have given him some literature so that he can do the calculation for himself. So far he hasn't finished it presumably, and I don't expect him to because it involves some advanced physics...

17
Flat Earth Q&A / Re: FE model support
« on: August 29, 2010, 09:26:08 PM »
ITT: Hortensius wins and Username's model is possible?

Nah, what about: Hortensius wins and Username's model is plausible?

What are the causes of Earthquakes in Username's model? I recall in some models there aren't any tectonic plates.

Don't know, but for my argument it doesn't really matter what the causes are... And plausible is definately not the right word...

18
Flat Earth Q&A / Re: FE model support
« on: August 29, 2010, 09:14:03 PM »
ITT: Hortensius wins and Username's model is possible?

Nah, what about: Hortensius wins and Username's model is gravitationally unstable...

19
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 26, 2010, 07:18:51 PM »
I do think its funny when internet dumbasses ask questions on the internet that the internet can easily answer.

So you think it is stupid to discuss subjects that have their explanations on the internet? What are you doing on a forum then? What have you actually understood of the copypasta that you posted here? And what is your level of understanding of cosmology in general? I'm sure that if you had the slightest clue about it, you would have been able to produce your own explanation instead of copy pasting your first google hit...

20
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 26, 2010, 07:10:55 PM »
Nothing in our causally connected Universe moves faster than the speed of light. Beyond that, ok. But your expansion explanation (+ redshift) is the right one I think...
Something moving <-- that way at .6 times the speed of light is moving faster than the speed of light away from something moving --> at .6 times the speed of light.

No, velocities don't add up like this.
So, something moving <-- 20 mph isn't moving away from something moving --> 20 mph at 40 mph?

No, although for 20 mph + 20 mph the answer is very close to 40 mph, it isn't exactly the correct answer. The difference is more pronounced for higher velocities. If you add up for example 450 million mph + 450 million mph, the answer is 620 million mph as opposed to 900 million mph.

21
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 24, 2010, 05:04:37 PM »
Should I interpret this as: "Could you elaborate on this, please?"

No, I would like proof.

Well, go and derive the equations of special relativity yourself then. The link provided contains all the relevant references. Come back when you've learnt something, including decent manners...

22
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 24, 2010, 04:25:23 PM »
Nothing in our causally connected Universe moves faster than the speed of light. Beyond that, ok. But your expansion explanation (+ redshift) is the right one I think...
Something moving <-- that way at .6 times the speed of light is moving faster than the speed of light away from something moving --> at .6 times the speed of light.

No, velocities don't add up like this.
Prove it.


Should I interpret this as: "Could you elaborate on this, please?"

I am not going to give you a course in relativity theory here, but if you want to know how velocities add up, check the following link and references therein: http://en.wikipedia.org/wiki/Velocity-addition_formula

23
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 24, 2010, 04:04:11 PM »
Nothing in our causally connected Universe moves faster than the speed of light. Beyond that, ok. But your expansion explanation (+ redshift) is the right one I think...
Something moving <-- that way at .6 times the speed of light is moving faster than the speed of light away from something moving --> at .6 times the speed of light.

No, velocities don't add up like this.

24
Green Lake.

Elaborate please. How is this Green lake mapped wrong in RE maps wrt to reality, and how are FE maps more accurate?

25
Is there one that is 100% accurate?

No 100% accurate Flat Earth map exists. Therein lies the problem.

First I need to see a 100% accurate Round Earth map.
Why would you need something from a theory that you consider to be false?

And tell us where the existing RE maps are inaccurate.

26
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 20, 2010, 07:40:55 AM »
You mean the light is absorbed somehow?

Yes, either absorbed or diffused. Just as our planet is absorbing and diffusing starlight.

The point being that there would still be variation in the night sky, as observed.

Clearly some light in the Universe is absorbed, buth this can't explain the paradox for the reason that if so much light was actually absorbed, the absorbing medium would heat up until it would start radiating optical light by itself...

27
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 20, 2010, 12:49:51 AM »
Why is this a paradox?

First of all, the Universe can be infinite but that doesn't mean the matter in it is.  You can have an infinite amount of space with a finite amount of matter.

Observations show that on large scales matter in the Universe is distributed homogeneously and isotropically, which means that the matter density doesn't just drop beyond some distance...
But we can't see from a large scale perspective, we can only see from a "in the middle" perspective.  If we could, I'm sure we'd see a lot of white.

Quote
Add to that the rate of universal expansion that is faster than the speed of light, diminished light from the inverse square law, and you get a good explanation.

Universal expansion, although not faster than the speed of light, might be a good hint.
I had thought it was faster than the speed of light. 

-Yep it is. 
The metric expansion of the universe allows for two objects to move away from each other faster than the speed of light because the objects aren't moving, space is expanding.  This is how we can see microwaves that are 13 billion years old, which is the current estimated age of the universe.

http://www.astro.ucla.edu/~wright/cosmology_faq.html#ct2

Some good info.


And, of course, the redshift as mentioned earlier.

Nothing in our causally connected Universe moves faster than the speed of light. Beyond that, ok. But your expansion explanation (+ redshift) is the right one I think...

28
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 20, 2010, 12:44:18 AM »
I'd suggest that stars occupy a finite portion of space and the light from that portion will be proportional to the inverse square distance. Light from stars cannot be stacked cumulatively behind one another, so one star at 10 ly isn't the same as 4 stars at 20 ly stacked behind one another.

The depth would be perceptible.

Add in a few million ly3 gas clouds and you've got starlight that in undetectable to the naked eye.

And starlight will also be scattered by gravity...


You mean the light is absorbed somehow? This can't explain the paradox either. If you absorb the light of so many stars, the absorbing medium must heat up until it radiates like stars. This follows from energy conservation.

29
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 20, 2010, 12:37:30 AM »
Can't be an explanation since the number of stars grows according to r3. So we still have a net increase of brightness as a function of r.

So we can see through stars to other stars behind them?

No we can't

Then the number of visible stars doesn't grow according to r3.

At the point that stars start blocking light of stars behind them, there are already so many stars on the sky that the sky will be extremely bright. Before this happens, the number of visible stars grows according to r3 roughly.

30
Technology, Science & Alt Science / Re: Olbers' paradox
« on: August 19, 2010, 03:05:50 PM »
Why do I state facts as questions? All it really means is that there are not a infinite number of stars in the universe, or rather it proves there are not an infinite number of luminous stars. Its not really a paradox, or a particularly powerful statement.

It could be that there's not an infinite stars on the heavens, but that's not the explanation for the paradox. The expanding universe causing starlight to redden by the Doppler effect is the true reason. It is observed that at very large distances the number of stars doesn't become less, but in fact their light becomes redder and thereby less luminous.

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