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Everything posted by Strange
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I agree completely that it depends on the definition of the words, especially "religion". Especially as it is extremely difficult to come with a definition of religion that really covers everything we think of as religion (it is one of those "hard to define, but you know it when you see it" things). But I struggle to think of a (meaningful) definition of religion that would make the original claim plausible. The closest I can think of is if "religion" stands for a specific religious organization. So someone might believe in their god but not think that any related organization (church or equivalent) has any validity or authority. So they don't "believe" in that organization. But I would argue that, because they believe in a god, they have a religious belief, in other words they believe in their religion, even if it is purely personal. Can you give a better example of someone who beleives in a god (or gods) but doesn't believe in a religion?
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The only reason they seek different answers is because they are asking totally different questions. The Michelson-Morely experiment was looking for variations in the speed of light as the detector moved through space. LIGO is looking for gravitational waves caused by things like binary black holes / neutron stars. If the speed of light did vary with the direction of movement (i.e. Michelson-Morely had a non-zero result) then this would affect LIGO as well and would have to be taken into account in the measurements.
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Thought Experiment on Quantum Entanglement Communications
Strange replied to Old Guy In Stanton's topic in Quantum Theory
There is no change in the other entangled particle. The only thing that changes is (knowledge about) the value of a property that you will measure. As you don't know what the value is going to be until you measure it, you can't tell that anything has happened. No box reacts. Because nothing changes. -
That is not quite the same thing as people handing out leaflets on the street (and you getting a bit annoyed by it). There are far worse things in the world than that. There are worse things on your high street than that. People who let their dogs foul the street, for example. Or, even worse, those who "clean up" after their dog in the woods but then think it is a good idea to leave bags of poo hanging in the bushes. Exile is to good for them. I would put them in a bag hanging from a tree. I think you are exaggerating things a lot. Surely not. By believing in God, you are, by definition, believing in a religion. On the other hand, one can believe in religion (seeing people all around doing it) without believing in god yourself. There are few (maybe no) medical treatments for which there is absolute proof. Therefore, applying your rule very strictly would mean they would have to go. This is exactly how dictatorships and extremist groups start. Initially, they start off saying "we must get rid of corrupt politicians" (or whatever). Then "corrupt" gets defined as "anyone who disagrees with us" and "politicians" as "anyone who expresses an opinion". Eventually, anyone who is not a member of their group is, by definition, suspect. And then, the leading clique start to suspect one another and they start plotting against each other in power struggles.
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Thought Experiment on Quantum Entanglement Communications
Strange replied to Old Guy In Stanton's topic in Quantum Theory
I think you are confusing "superposition" and "entanglement". Not the same thing (although related). The cat thought experiment relies purely on superposition, it does not require entanglement. Nothing changes. (Except that the person at the transmitter end knows what entangled value you will read, if/when you read it. But they can only transmit that information to you at light speed.) -
You might want to work through the pages here: http://profmattstrassler.com/articles-and-posts/particle-physics-basics/fields-and-their-particles-with-math/ball-on-a-spring-classical/ They are a bit mathematical (and he skips some steps, which can make it hard to follow) but you might find it useful.
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Also, there isn't "a gene for this" that you could just transplant. It is a whole mechanism that is distributed across large numbers of genes and how they are expressed. But people are working on this. There are attempts to get nerve cells to regrow. And this recent story about a new treatment for cataracts: http://www.bbc.co.uk/news/health-35762713 OK, not growing a new hand, but these small scale things may be the best we can ever do.
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And we are asking: how would you tell the difference?
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Someone should set up a website offering to match up potential super-heroes/villains with upcoming accidents.
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None of this appears to have anything to do with the question of whether we can tell if particles are real or just a useful model. Or even if there is any difference between those two concepts. But it sounds a bit like you are talking about "emergent phenomena"; behaviours which are not obviously predictable from the system (e.g. the complex pattern of waves which emerge from the interaction of wind, water and gravity).
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You should try relaxing. There are still a few brutal, repressive regimes. The number is dwindling as more liberal views take hold. So I'm not sure you will find one that is vile enough to suit you. You might just have to take up a new career and become an Evil Dictator. It can't be too hard. It wouldn't entirely stop that. You would also have to exile the merely superstitious, those who believe in alternative medicine, the generally ignorant, pathological liars, and people who believe in ghosts. And if you are very strict about the definition of proof, you will also have to throw out the philosophers, doctors, scientists and engineers. It will just be you and a bunch of mathematicians.
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What is the connection between the big bang model (1) and plate-tectonics (2) ? (1) Which, contrary to the pop-sci you might have read, is a description of how the universe has expanded and cooled over the last 13 billion years. (Not a description of an explosion or the creation of the universe.) (2) Which is a good example of paradigm shift -- in my lifetime -- due to the slow accumulation of overwhelming evidence. Actually, the same is true of the big bang model so they have that in common. Anything else?
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Goedel's theorem applies to formal systems, not theories. This, by itself, makes the rest of your posts irrelevant. Also, Goedel's theorem says nothing about paradoxes. Physics does not have the answer to all questions. For example, we don't know how to form a theory of quantum gravity. So for many questions, the only answer is "don't know". On the other hand, physics can give multiple answers to a question. For example Newton's theory of gravitation describes gravity as a force that acts instantly over any distant. GR describes it as the geometry of space-time that propagates at the speed of light. Physics doesn't deal with truth. Also, physics does not prove anything, thus Goedel's theorem is irrelevant. Physics is incomplete (as is all science) but not for the reasons you claim. It is because Zeno's paradox has nothing to do with physics. Also, the apparent paradox is solved in modern mathematics. This sounds like a crude description of the way science works. Which is exactly why science is so successful despite the fact we know it is always incomplete. I can't be bothered to read something by someone who: a) Doesn't know what Goedel's theorem is b) Doesn't know what science is c) Doesn't know how science works
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But the only way we have of "checking reality" is to make some measurements, do some experiments, etc. So far, the results of all these are consistent with there being things we can model as fields and particles. Whether they really exist or not is probably unknowable. Until we have some experiment that says so.
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Having a spirited discussion with a friend about climate science
Strange replied to DaveinJapan's topic in Climate Science
That is proof of how powerful the conspiracy is. Anyone who seriously believes that sort of conspiracy is not open to rational discussion. It is exactly the same as people who believe the moon landings were faked. It doesn't matter how irrational their belief is, or how much evidence is presented, they will just latch on to one tiny detail and insist it proves they are right. -
Ha. I once had to rewrite the user guide for a new product as a requirements spec because the new marketing man said we couldn't have a product without requirements.
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Shifting LIGO to the binary. Thought experiment.
Strange replied to Robittybob1's topic in Speculations
So you trying to detect changes in gravity by it stretching the arm of the experiment by varying amounts? It would be straightforward to calculate the changing (Newtonian) force of gravity at some point near the pair of objects. You could do this in a spreadsheet as previously suggested (in one of your other threads). It is a pretty straightforward application of Newton's law and vector addition. If you wanted to convert this to what would happen to a LIGO type instrument (although I'm not sure why you would) you would have to make some assumptions about the mass and stiffness of the structure to work out how much it would be affected. This would effectively be a tidal effect over the length of the arm. I'm not sure what this would tell you beyond the changing force of gravity that would make the extra complexity worthwhile. -
It may be a specification problem. But is more often an implementation problem: the code doesn't match the specification. Or it could be a compiler bug. On the other hand, as most code (rather depressingly) seems to get written without a specification, maybe you are right. And, of course, with no specification there is little scope for formal validation. You could check some properties that should be true for all programs (memory leaks, all memory accesses are valid, etc) but you couldn't check that the program is "correct". Of course, just having a specification (even without any attempt at formal validation) will improve the quality of the code and shorten development time. Which is why it astounds me that so many companies don't do it. The number of times I have had the "It will shorten development time" "But we don't have time" "But it will save you more time than you spend" "I'm sure it will but we just don't have time" conversation is staggering.
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Shapiro (or Shapiro-like) delay of GW signals (split)
Strange replied to DanMP's topic in Speculations
Correct. The system generates graviational waves. No it doesn't. It says "it" (singular) will generate gravitational waves. "It" is very clearly the pair of objects which can be compared to a dumbbell. Of course not. It will radiate continuously, as long as it is spinning. -
Shifting LIGO to the binary. Thought experiment.
Strange replied to Robittybob1's topic in Speculations
You could use Newtonian gravity to answer that (incorrectly). In which case, they would be in a stable orbit like any other pair of masses. But, of course, they would not be creating gravitational waves, which is why the orbit is stable. And LIGO would detect nothing because there would be no gravitational waves. -
Shapiro (or Shapiro-like) delay of GW signals (split)
Strange replied to DanMP's topic in Speculations
Of course they weren't: they were in orbit and therefore accelerating. Their orbits were getting faster so they weren't at a constant speed, either. But they are not in the set of things that don't generate gravitational waves and so are not covered by the clause "symmetric rotating object of constant velocity". -
Shifting LIGO to the binary. Thought experiment.
Strange replied to Robittybob1's topic in Speculations
So you want to simplify the situation to the point you can use a theory that doesn't generate gravitational waves (and then make some ad-hoc assumptions to add them back in)/ Any gravitational waves generated that way will be purely fictional and have no connection to the gravitational waves that actually exist. As such, they would not provide any sort of answer to your original question. You might as well just keep it really simple and make up the answer you want. So, the only way you are going to get any sort of realistic answer is by doing the full analysis. (And note that LIGO is quite possibly larger than the system generating the waves! But presumably you could use a much smaller detector as the waves would be much greater in magnitude.) -
Those are (largely) just checking for syntactical correctness. They do little or no semantic validation. Formal validation of code written hardware description languages (effectively, software that will be compiled into the design of a silicon chip) is commonly done. This is because of the huge manufacturing costs and the difficulty of replacing faulty hardware. Because it costs almost nothing to distribute buggy software and the issue updates, there is no incentive to be as careful with most software. (Embedded software is treated a little more seriously.) I think the thread was revived by a spammer. (And it is quite an interesting subject...)
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Shapiro (or Shapiro-like) delay of GW signals (split)
Strange replied to DanMP's topic in Speculations
You don't seem to reading what is written. He was describing objects that do not generate gravitational waves, not these or similar black holes. "Not all objects emit gravity waves. Any symmetric rotating object of constant velocity will not produce waves." -
Shapiro (or Shapiro-like) delay of GW signals (split)
Strange replied to DanMP's topic in Speculations
Except it didn't "disappear". That is hardly surprising: the orbital frequency was calculated as half the frequency of the signal. You have yet to show that this claimed effect matches either the theoretical predictions or the observations. As such, there is not reason to take it seriously. And that seems to b a large part of the problem. Of course it was. Or perhaps you would like to show an alternative to the Einstein Field Equations that reproduce all the effects of GR but not Shapiro delay. Then use that to predict the behaviour of black holes. And then add back a delay caused by GR (but ignoring all the other effects of GR). Do you begin to see how silly that sounds? This has nothing to do with "truth". What makes you think they need to be included? Light passing a black hole would show the Shapiro delay. So would gravitational waves. Detecting this would require a fairly continuous source of gravitational waves that was then occulted by a large mass. You would then see a phase shift in the signal as the mass passed in front of it. I imagine we are many decades from being able to make those sort of observations, never mind the probability of such an occultation happening. Dan is not talking about some third mass that the waves might have passed. Any such mass (and there may have been many galaxies in between us and this event) would not have been included in the calculations (as they are not relevant to the generation of gravitational waves). They also would have been static during the period of the detected signal and so can be ignored.