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Everything posted by [Tycho?]
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When Galaxies collide, supermassive black holes?
[Tycho?] replied to The Peon's topic in Astronomy and Cosmology
Well for a black hole there isn't a whole lot to rip at. If it was a Kerr (rotating) black hole then you might get a bit of a bulge in the event horizon... maybe.... but I wouldn't count on it. Once one of the black holes enteres the others event horizon, they are essentially the same thing. Wait a minute. Ok, so two black holes merging, big and small. Lets say the smaller singularity has just passed over the event horizon of the larger black hole. Yet there would be something of a bulge; if an observer was orbiting the larger black hole, the observer would notice a stronger gravitational attraction when he was over the point the smaller singularity had just entered. Here I just whipped up a paint diagram http://i23.photobucket.com/albums/b390/Traxus/Blackhole.gif I dont see how this can work, because it would allow us to observe what was inside the event horizon of the large black hole; we would know a mass is present, and would even be able to tell that its a black hole due to the pressence of a singularity "bulging" outwards. Could someone point out to me why this is incorrect? -
Something like light has a great deal more energy than radio waves. As such, where light waves are absorbed by atoms when an electron goes up a quantum level (im not sure if this is the correct terminology), radio waves do not have the energy to do this, and will not be absorbed as readily. So light is easier to absorb than the radio waves, which is why the radio waves can travel through things like walls to reach your radio inside the house. This also depends on the antenna. Certain lengths of antennae can absorb certain wavelengths of radio waves. I dont really know much about the relationship though, but talk to swans more about it, since it is very true that light would need a much MUCH smaller antenna than radio waves.
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Less than 100 years in the future you're beat for any sort of terraforming. In that time frame any colony would just have self-enclosed structures, and probably not very big ones either (100 years is not really much time considering the magnitude of the task). Terraforming is a very time consuming task, and one that would require very large feats of industrial production as well as technological advance.
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You'd power a fusion engine with stuff that fuses. The most likely possibilities are deuterium-tritium fusion, deuterium-deuterium fusion, and deuterium-helium3 fusion. I got these straight from the wiki article by the way, perhaps you should look at it again http://en.wikipedia.org/wiki/Nuclear_fusion
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You've got your decays mixed up. Beta netative decay is N -> p + e- + antineutrino. Beta positive is p -> N + positron + neutrino
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Food Cravings While Pregnant
[Tycho?] replied to SorceressPol's topic in Anatomy, Physiology and Neuroscience
Apparently some women get the urge to eat dirt while pregnant, which means they have an iron deficiency. I just heard this somewhere, not sure of accuracy. -
I think you should actually read a little bit about the big bang so you develop some idea of what the hell you're talking about. How does an ultimate beginning represent a fatal flaw? Since when have scientists rejected the big bang theory because of this (this is a rhetorical question, since I know they havn't rejected the theory, its the only mainstream theory used to describe the begining of the universe). And it also does not imply an ultimate begining anyway. Our theories cannot predict what happend before the big bang. Does it mean that there was nothing before that? We dont know. Nobody has any idea what went on before the big bang, if anything did at all. The theory doesn't try to explain that, so its certainly not flawed in that regard. I'll bold this for you to make sure you notice it: The Big Bang theory does not explain what caused the Big Bang, nor what occured before it. It is not meant to.
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I think he means best theory yet proposed to describe these phenomenon. I doubt he's saying that Big Bang is so much cooler than General Relativity, or whatever.
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I'm shy, insecure and self conscious.
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I did not say that. A theory will not be thrown out the instant someone finds a possible error. The big bang explains a lot of things, so contradictions may be the result of bad data. If the theory itself is flawed, then it will only be rejected once a superior theory is proposed. The big bang is not as perfect as it is? This doesn't make sense. And I've never heard it said that the big bang theory is perfect anyway. Right, Theory is not truth. I stated that the theory will probably need revision. I'm just saying this because there are a lot of big unanswered questions about the universe and the big bang itself (like how inflation works). The theory could be bang on at this moment, but since there is so much we dont know I'd bet on it needing some changes at some point. I dont know how it would be revised because there aren't any fatal flaws in the theory yet that need revising. I dont "believe" in the big bang theory. I accept that its the best theory we have at the moment, but I am perfectly willing to reject it if a better one comes along. Again, it MIGHT need revision, thats just opinion on my part. All scientists know that theories have limits, they know it far better than laypeople. No you dont throw out a theory if it has limits (unless these limits are very large). General Relativity does not explain things on quantum scales, this is quite the limit. Do we throw it out? No, because its extremely useful. But at some point something is going to have to change in order to get quantum mechanics and general relativity to work together. Einstein worked his theories to make the universe steady state. Once it was shown the universe was expanding he immediately fixed his blunder. As for the rest, who cares? Carl Sagan thinks the universe will collapse and expand again. Good for him. Once he has evidence to back this up, I might start to believe him. At the moment the expansion of the universe seems to be accelerating, meaning that it seems rather unlikely the universe will collapse at all. I dont know what came before the big bang, nobody does, because we have no way of observing or predicting it at this time. If god made the universe, then what made god? If your response is that god doesn't need to be made, then why do you say the universe does have to be made?
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My thoughts on this matter are that you have the education of a 10 year old. For one thing "the Scientist" is a rather odd term. Scientist is plural (there are a few more than one scientist in the world) and is not a title, and so is not capitalized. I am admitting that the big bang theory is almost certainly not perfect, and probably needs some revision. Point of how the universe came to be? Seeing things in a positive way? I have no idea what you're talking about. What the hell are you asking? If you want to know what the theory states look it up, any source will give a better explanation than I possibly could. Lets get a few things out of the way. If a scientist says something, this is not something that everyone in that field thinks. Just because a scientist says something, does not mean its a theory, or that there is any evidence for it. Anyone can come up with an idea like this, not just a scientist. I have looked this up. I've never seen a theory that actually states that the universe oscillates in such a manner, and have never heard of any evidence to back it up. If you can provide a link to a credible source, be my guest, although I dont know what it would prove in this argument. Since this is a physics forum I'm not going to directly argue the evolution based points. There are other forums on this site where people can show you the faults in that. Because of the current laws of physics, there is no way to determine what happend before the big bang. This is why there arn't any decent theories to explain what caused the big bang, and also precludes any that suggest it oscilates.
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Nothing that I really know of. One could use powerful electric fields to repel charged particles, or huge magnetic field manipulation could probably deflect larger objects. Nothing like the classic star-trek force field though.
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Blue White shooting meteor over D.C.
[Tycho?] replied to bender0569's topic in Astronomy and Cosmology
UFO lolozor!!~~!!1! -
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This was thought of a long time ago, largely work done by Hawking and whats his face.... Roger Penrose. Now correct me if I'm wrong here, but I believe the reasoning went like this: matter falls into a black hole, where it is compressed so much that it becomes a singularity. Since the big bang is matter moving outwards, this can be thought of as a black hole in reverse, with the matter going out instead of in. As one moves back in time, the matter of the universe will have been closer together. At only a short time after the big bang all the matter in the universe would be at a super tiny size, and the further back you go the denser the matter becomes. Once one goes to time zero one reaches a point where the density is infinite. I believe this is where the big bang was first proposed to have started as a singularity. (if the singularity acutally exists is open to question, its simply what GR predicts)
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It could have evolved such that it trapped some species of insects, while allowing others to escape. This would keep the mutation in the gene pool and allow it to develop the genes to digest the fly. This is just speculation of course.
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In case you havn't heard, RFID tags (like the anti-theft devices that are in most CD/DVD cases) have been getting a fair amount of press lately, and many people are concerned about privacy, namely that RFID tags in products could be used to trace what sort of things a person buys, or can be used to trace the person themselves etc etc. Basically I am wondering how one would block and RFID chip. I was thinking that just having a faraday cage around it would block it, as that would at least block the radio waves. However I only have a vague idea of how RFID chips work, and some might use magnetic fields instead of radio waves (I have no idea). So would a faraday cage do it, or is something else needed?
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Well even if physics is "out of control" (something I would fine quite unlikely, considering how much has been learned in the past 100 years) it doesn't really matter if it is. If a theory is accepted or rejected by the mainstream only matters so much. If a rejected theory allows people to make more accurate predictions of real world events, it will gain in popularity, regardless of what anyone else thinks. Similarly an accepted theory that is trash will not allow people to make real predictions, and so wont be used. Herd mentality certainly does exist in physics, but the herd goes where the accurate predictions are.
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How exactly would this save fuel? You still have to get everything into orbit, if you do it over a period of time it may be more spread out, but you still have you use a ton of energy to get it into space. And once you're in space, why leave booster rockets behind?
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Look at my sig.
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If your asking on internet forums I'd say you have quite a ways to go.
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The diagram does anyway, it doesn't seem to mention it in the article itself. This depends largely on if you want your sphere to spin or not. I dont see why you'd want it to, but spinning would greatly increase the stress on the structure.