mzatanoskas

Thanks swansont, this is just special relativity 101 isn't it. Trying to get my head round its most basic tenets almost feels like a religious experience it's so counter-intuitive. Just to check I've got it right: In the wonderful world of special relativity then the following situation is just normal: There are 3 light emitting objects in a line: A, B and C. A__________>>>B__________C<<<__________ 1. A is "stationary" 2. B has a velocity of 0.6c measured by red shift from A (going away from A towards C) 3. C has a velocity of -0.6c measured by blu shift from A (going towards A and B) 4. So B has a velocity of **funky equation**c as measured by blu shift from C? (0.8823529411764707c according to the link you gave me)

I know there's Stellarium for my planetarium needs, but are there any noob friendly free orrery programs out there? Preferably with an easy to use interface and nice graphics, more for fun and to get a feel of the solar sytem than to accurately map stuff? I've seen a bunch of stuff online, but it seems very much of the windows 98 variety and focused on accurate data and simulation with no eye candy.

Thanks for your answers Atheist. This was the question that was getting to me given the special relativity speed o' lite don't change thingy... So can I ask in the above situation, what speed would the blu shift represent? If I stick in some numbers: say the light is moving towards the observer at 200,000 km/s and the observer is moving towards the light at 200,000 km/s, how much blu shift would there be? Not 400,000 km/s because that is more than c, so does blu/red shift max out at c, or is there some funky equation which shows that it gradually gets closer to but never reaches c? Given your answer to 2), I guess though the amount of shift is very limited. Say from infrared to red, or violet to UV only given the speeds it takes to shift 10 nm of wavelength. hmm, I know nothing of these shifts I'm afraid! I thought the red shift was to do with relative velocities and was the evidence for the expansion of the universe... I may be using lots of terms incorrectly and confusing the issue.

Was watching some astronomy program which was talking about red shift and it got me wondering how much red/blue shift is possible. Now I don't have the knowledge to do the calculations but according to wikipedia, in order to get a yellowish light to appear orange or green (a change in wavelength of 10nm or so), the light source would have to be travelling at about 5200 km/s away or towards you. So first question: 1. If we discounted the limit of the speed of light, theoretically radio waves broadcast by some object traveling at a gazillion miles an hour towards earth might start microwaving us and at yet faster speeds become visible? Second question has a bit to do with special relativity but my understanding of the subject is basically non-existent. 2. Say you have a light source traveling as close as possible to the speed of light, and a receiver traveling towards it also at a speed close to that of light. Would the amount of blue shift measured by the receiver reflect the relative velocity that is greater than the speed of light?

Thanks for the suggestions. Unfortunately I don't speak Turkish but I'll check SPCF out. I'm having real trouble finding specific well frequented forums for things like economics and art history. I'm not sure why they shouldn't exist though. When those topics feature as subforums, they tend not to have many visitors and the level of expertise is often questionable. Maybe forums are the wrong medium and I should look at mailing lists instead.

Hey daniellos3, Severian's post comes across as a light-hearted joke, I'm sure he wasn't trying to be offensive. Like the other guys said, IQ tests are just tests. We don't measure the greatness of our intellectual heroes by their score on some test. I wonder whether you don't feel like a bit of an outsider amongst your family and friends and instead have defined yourself as "the intelligent, philosophical one". If so, I'd say that it is your interest in intellectual things that makes you intellectual, not some IQ score. I wouldn't take it seriously. It sounds like you are quite an earnest kind of guy and have high ambitions in life which is great. But I would suggest you go a little easier on yourself, "[figuring] out the unsolved mysteries of the universe" is a pretty lofty goal seeing as no other human being has managed that yet! Also, the "average" life can often include so much that is extraordinary, deep and fulfilling. Please don't believe that to validate your life or yourself, you need to be the "most intelligent", "the best", to be praised or have great "success". Pursue your dreams by all means, but stay open-minded about life and about what might bring you happiness and fulfillment.

Synthosis, Here's a famous scientist and a christian who talks about these issues: Dr Francis Collins There are a fair few videos of him on youtube including this short . He has a website: biologos.org And a best-selling book: The Language of God: A Scientist Presents Evidence for Belief

I agree with quite a lot of what you said re the OP's problem, but... Why is it more arrogant to disbelieve something because we cannot see it or understand it, than believe something because/even though we cannot see it or understand it? I mean, do you believe in a God who demands your death as an infidel for not obeying the edicts of the Koran and the hadiths as understood by fundamentalist jihadis? Or the God of the Westborough Church who entraps America in conflict in the middle east in order to punish it for not persecuting homosexuals? Less offensively, how about Shiva, Isis or Zeus? How about the existence of the "ether", or ghosts, or elves, or Uri Geller's spoon bending? I'm sure you cannot see any of them (apart from Uri Geller) or understand the beliefs, but I don't think you are arrogant for not believing in their existence. Personally, I tend to see much less arrogance in scientific as opposed to religious modes of thinking. However whether individual scientists or atheists are arrogant or not is a different matter.

I often tend towards a pretty virulent atheism myself, but like arguing the "other" case so to speak, to keep me on my toes. Firstly I'm guessing that your definition is of a literal biblical Christianity? The definition is not necessarily accurate of all religious/spiritual beliefs. Also, words and concepts are slippery things. For example "evidence" to you might have different connotations to others. I'm sure many religious people would assert that their overwhelming and deeply felt faith qualified as "evidence" even though we might disagree. Regardless of the definition, as I mentioned in my first post, I have met many people who have derived great strength and solace from beliefs that they have not been able to accurately or logically describe or explain to me. Life can be pretty shitty and I've experienced enough to know that like everyone else I have a breaking point. If logically incoherent beliefs can help you through, good for you. Where does it say that something has to be "true" to be beneficial to someone? Finally from the OP's point of view, a belief system such as you describe may simply be very beneficial if everyone you know and care about in your community subscribes to it.

Hey Syntho-sis, I read your post and spent ages trying to come up with some deep heart-felt insights about your situation. However I'm dying of man-flu right now and can barely string a sentence coherent together. Instead I'm going to resort to bullet points: 1. I come from a very different background (no religion) but have still had problems when my philosophical beliefs haven't fitted in with those of my friends and family. 2. There are always going to be contradictions in your beliefs in life. Some you may be able to deal with, some not, some you'll forget about, others not... It's an ongoing process. 3. I'm guessing a conservative, literal biblical Christianity is not going to be for you. But that is not the only religious or spiritual mode. 4. I'm sure there are many, many other Americans in your position with a bunch of forums and mailing lists on the web for you to talk to. 5. Don't read Dawkins to try and come to terms with your religious and scientific beliefs!! I don't think he'll give you much solace. I'm sure there are plenty of books written by competent religious scientists out there. 6. Throughout history, "God" has been used to explain all sorts of facets of our existence that we didn't understand. Modern science is rapidly rendering most of this irrelevant. However that has no bearing on whether a belief in God or religion is important to you on a personal level. 7. Some people I know have tried to explain their faith to me, but ended up spouting contradictions and downright confusion. However these same people have drawn great strength from that faith and triumphed in difficult situations in which I would probably flounder. 8. I need to have some Lemsip. It feels like a pig pooped in my head. Good luck to you.

Thanks for your reply John. After reading your post a couple of times and that gravitational potential >> kinetic >> heat stuff, I think I realise where I was going wrong. I seemed to be imagining pressure itself as creating heat, instead of an increase in pressure creating heat. So all that is really happening in my example is that when the moon is initially formed, gravity compacts the rocks and pressure increases and the temperature goes up. Like when you pump up a bicycle tyre. Once you stop increasing that pressure, then no more heat is generated. The tyre and the moon just cool down. So over time, all you get is a cold moon. No new radical theory of thermodynamic mass/energy equivalential heat decay. Thanks again John, I learned something today. My reconstructed thought experiment: 1. Imagine a large mass of rock in space, say the size of our moon. 2. When the moon is created, the gravity of the moon causes pressure on the rock inside the moon, and this increase in pressure causes the rock to heat up. 3. This heat conducts/convects to the surface and then radiates out into space. 4. Now jump forward some ridiculous amount of time. The moon is now cold. 5. The implication therefore is that nothing of any great interest has happened here at all. 1 confused thought down, many, many more to go...

Hello. I recently decided that I should use the internet more to get closure on all the strange and sometimes silly ideas and questions that occur to me for whatever reason late at night. Googling "best science forum" gave SFN, so I registered here. I was wondering what other forums people use for science and other related subjects. What are the best forums, with the best posters (educated but noob-friendly)? Topics I am interested in right now are: Economics, Geology, History, Art, Medicine, Religion (pretty much everything really) Any recommendations? Thx!

The Bad Science blog on which the book is based is great too, although I'm guessing most users here know about it already: Edited version at Guardian newspaper site. Original version at Ben's blog.

Hello everyone. I sometimes get niggling questions, or half baked ideas about science/religion/philosophy or whatever that keep me up tossing and turning for oh... a good 5 minutes at night. The other day I decided I might as well register on some forums where clever people could tell me what was what, and I might actually benefit from my midnight pondering. So here goes my confused thought experiment #1: I started thinking about this after reading some article talking about the geology of the earth, please excuse any shocking beginner logical/scientific mistakes! 1. Imagine a large mass of rock in space, say the size of our moon. 2. The gravity of the moon causes pressure on the rock inside the moon, and this pressure causes the rock to heat up. 3. This heat conducts/convects to the surface and then radiates out into space. 4. Now jump forward some ridiculous amount of time. If the moon has the same mass, then presumably it is still emitting heat and we have just flouted the first law of thermodynamics. 5. The implication therefore is that as the moon radiates heat, so it is losing mass. Over time, the mass would be less, gravity less and heat emitted less. Hence mass and energy are the same thing or intimately related. Well that was my thought process. So my questions are: 1. Is that essentially a coherent thought experiment, or am I making any terrible mistakes? 2. If valid, then what is the actual mechanism at a molecular level of this kind of heat decay? 3. That will do for now. Thanks for putting me right guys!