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Everything posted by Strange
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https://en.wikipedia.org/wiki/Galaxy_merger Lots more interesting information there.
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The speed of the expansion of the universe at the beginning?
Strange replied to noctua's topic in Astronomy and Cosmology
Expansion is not a speed. It is a rate of proportional increase in distance. The speed of separation of two points is proportional to how far apart they are. The "faster than light" description of expansion is just journalism. -
How is the cause for the expansion of the universe explained?
Strange replied to noctua's topic in Relativity
It is a consequence of the curvature of space-time, the same thing that causes gravity. Imagine two people standing near the north pole. They both start walking due south in a straight line. Because they are following lines of longitude, they gradually get further apart. The same is true of objects in space. -
Morality, religion and language are entirely cultural. There is no genetic component. Arab populations are very mixed because they have spread over such a large area in the past. (I suspect "Arab" is a linguistic rather than an ethnic/genetic definition). Of course, you will find different frequencies of some alleles in different populations. That can be used to study the movement and relationships of groups in the past.
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Yes we can. We have these things called "clocks". (I hope this isn't going to turn into yet another "time doesn't exist it is only change/movement/bat-poo/etc") Postion is not absolute either. It can only be defined relative to something else. It seems to work extremely well. In everyday life, if you want to meet someone, you need to specify both the spatial location and the temporal coordinate. And, of course, GR is an extremely succesful theory. Can you give an example of these crises? That is a bold claim. Can you back it up?
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I don't think visualization is related to other spatial skills. I can't tell left from right - the words are exact synonyms to me - I worked out the "write=right" mnemonic when I young and have relied on it ever since (good job I wasn't left handed!). After more than 50 years my ability to understand left and right hasn't improved with practice. But I have no problem manipulating 3D shapes in my head. When I studied chemistry I never had to use the "ball and stick" kit to understand the structure of the molecules we were studying. I could work out which were stereoisomers, which were just rotated, etc.
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The "theory" (in the general sense) doesn't require a non rotating, symmetrical sphere. Only the Schwarzschild solution to the equations of GR require that. There are other solutions that describe a rotating sphere, a charged sphere, a rotating charged sphere, a homogeneous distribution of mass, and so on. You could have a non-spinning object as well. There is no theoretical reason why not. It is the distance from the center. The specific value rs refers to the Schwarzschild radius. The event horizon occurs at a radius, the Schwarzschild radius, which is proportional to the mass: double the mass and you double the Schwarzschild radius. If the mass is concentrated inside the Schwarzschild radius, then it will be a black hole. In this case, the mass will be inexorably crushed to a radius of zero. If you are describing the tidal forces, then these would tend to tear you apart rather than crush you. And would be greater for a small black hole. This is certainly true within the black hole. Once matter gets inside it will, according to GR, be crushed to zero size. It is generally assumed that this may not be realistic and that there may be other (quantum?) effects that prevent this. But we have no idea what they might be. For example, string theory describes black holes as "fuzzballs": https://en.wikipedia.org/wiki/Fuzzball_%28string_theory%29 And some recent work suggests that quantum effects may mean that the event horizon itself is not well defined.
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Does Dark Matter imply Dark Gravity?
Strange replied to mothythewso's topic in Astronomy and Cosmology
The thing is, the "non-clumped" nature of dark matter is pretty much what would be expected for "stuff" that doesn't interact much. It doesn't need a new, unknown repulsive force to explain it. And that large-scale structure is largely created by gravity - including dark matter. Expanding is just a natural consequence of the same description of space-time (General Relativity) that explains gravity. Mordred posted a nice link to a (relatively) non-mathematical explanation of this, in another thread. No problem. Hope the answers make sense! -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
How is that relevant? Do you think that it would be acceptable in a murder trial to point out that Ghengis Khan killed lots of people and therefore the accused must be guilty? Maybe you need to take a short course in logic or critical thinking. -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
Yes, by making predictions and comparing them against evidence. I'm not sure what that means. Yes, the lack of evidence means you have no hypothesis. A baseless opinion is not a hypothesis. A wild guess is not a hypothesis. Do you have the right to post opinions and wild guesses on this forum? Probably not. And yet you have no basis for make such an attack on science. Would it be reasonable for someone to accuse you of, say, being a child molester? They have no evidence, they just think it is possible, so why shouldn't they make the accusation? It is not an attack, they are just pointing out the possibility. -
Fair enough. Except this is his prediction: So not only is the change not described quantitatively, it isn't even described qualitatively. Just "some attribute of the light will be changed in some way." What will change? Don't know. How much will it change? Don't know. Will it get bigger or smaller? Don't know. Even Doris Stokes would be embarrassed by a prediction that vague. This isn't true. There are phenomena which are, as far as we know, entirely acausal.
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I have no idea. These are some of the questions I might ask: 1. Is there any evidence that the size of the atmosphere has increased? (This is something that is monitored pretty much continuously, as far as I know) 2. How much would the atmosphere have to grow by to cause the observed thinning? 2. Is there any mechanism by which halocarbons could cause the atmosphere to increase in size? By that much? 3. Why would this cause a decrease in ozone only over the polar regions, rather than uniformly? 4. What is wrong with the well-studied chemistry that enables halocarbons to catalyse the breakdown of ozone? 5. Why do you think the ozone is not depleting?
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You miss the point: they BOTH predict it. Which one is right?
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High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
Yes, like all those smug people who boast about how clever they are to "think out of the box" (but apparently not clever enough to learn anything about the subject). You keep saying this, but when challenged to provide an example or some evidence, you change the subject. Why is that? Oh, yes, that's right: you are lazy and don't know anything about science. If you are too lazy to support your own nonsense, why would anyone else do it? No. Not OK. -
Both Newton's law of gravity and General Relativity predict that light will be affected by gravity. So how do we know which is correct? They make quantitative predictions so we know that one is wrong and one is right. So how, exactly, does your prediction differ from that of GR or Newton? My prediction is that something will affect something else to a greater or lesser extent. So I win.
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High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
So not really an example of someone who knows nothing about the subject, can't be bothered to learn anything but throws out random ideas that he hopes make sense and expects others to check. -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
No. The out-of-the-boxers like to shout about how important it is to be lazy and ignorant, but never actually come up with anything useful, nor any examples of people like them who have come up with anything useful. On the other hand, intelligent, well-educated, hard-working and imaginative scientists or engineers? Thousands, maybe millions. And lots of practical results. -
Talking of high-speed baseball: https://what-if.xkcd.com/1/
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High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
I can't think of a single example. Can you? Or is this another empty claim? Anyone can do that. That is the easy bit. So well done for picking the job that requires no knowledge, no intelligance, no effort and gets no results. No one is "unsettled" by the same idiotic claims we have seen hundreds of times from all those people who think it smart to "think out of the box" (aka "make crap up") instead of learning. Yes, let's focus on the topic: YOU are the one who refuses to discuss it. Please provide some evidence that science today has become unscientific. Just one example. It can be invalidated trivially: you made it up and it isn't true. "He has a face totally unmarked by the ravages of intelligence." -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
OK. Why not start a thread on the evolution of invisible pink unicorns? Or the type of underwear Santa Clause wears? They would be far more sensible than this one. -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
What do you think the claimed relationship is? What do you think is wrong with that relationship, specifically? And why? -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
As your conspiracy theory is completely baseless, you won't have much luck. What "clues" do you have? Do you have any specific problems with the theory? With the evidence? Or is it just a personal dislike of general relativity (the only theory you have mentioned)? -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
But not just baseless speculation. Where is your evidence? It hasn't. Evolution has been known about since. at least, the domestication of plants and animals. Evolutionary theory has a shorter history but evolutionary theories have been discussed for at least 200 years. Because of lack of evidence. So, without any evidence, we can just dismiss your "speculation" as the nonsense it is. -
Phenotypic Plasticity and Speciation
Strange replied to starlarvae's topic in Evolution, Morphology and Exobiology
Not really. There are plenty of examples where two species can succesfully interbreed with suitable intervention. After all, reproductive isolation could just be caused bya mountain. -
High-energy physics, cosmology today are closer to scams than science
Strange replied to nobox's topic in Speculations
It is hard to correct an idea that appears to be based on no information at all. Perhaps you could explain what you think is wrong with either the theories or the evidence. As you mention black holes and the big bang, p[erhaps you would like to show the errors in the Einstein Field Equations? Or why observations do not match the predictions of the theory? As for collusion, why would scientists conspire to deprive themselves of the big prizes that come from new discoveries? Why would people want to put money and effort into wrong ideas, instead of exciting new stuff?