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Everything posted by Strange
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These two powers are not connected to one another. One is the value of the density and the other is the units of density. The first one is just the value of the density being shown in scientific notation: 1.24x103 = 1,240 The second one is representing the fact that the units of density are mass / volume; in other words kg / m3. Dividing by a power is the same as multiplying by the negative of the power, so the units of density can also be written as kg m-3. You have one value measured in kg and another value measured in kg m-3. If your calculation is correct then, as Ghideon suggests, the result should have the units of volume (m3) because the units can be multiplied, divided or cancelled like numbers.. This process of analysing the units in an equation is called dimensional analysis and is a valuable way of checking that a calculation makes sense. It can also, as in this case, tell you which number needs to be divided by which.
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If this is true and it is "well known" then it will be taken into account in measurements of supernova apparent brightness and therefore distance. (My guess is that the effect is much smaller than the uncertainty in the absolute brightness, but I don't have any data to support that at the moment.) I know that light absorption is taken into account when Cepheid variables are used as standard candles. So I see no reason to doubt the same is true (or, at least that it has been considered) for supernovae.
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It is not about uncertainty, it is about testability. How would you test if the universe is actually 13.8 billion years old or it was created last Thursday but made to look as if it were 13.8 billion years old? It is impossible. I have great faith in science as the best way of understanding and describing the world. But what you are suggesting is simply not possible. You can think of all sorts of tests based on guesses about the way we might create such a simulation. Then you can show that the universe is or is not consistent with that type of simulation. But what you can never do is show that the universe is not consistent with itself.
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You can show that the set of integers, for example, is the the same "size" as the set of fractions between 0 and 1 because you can work out a way of mapping from integers to fractions (or vice versa). In other words there is a one-to-one mapping between them (there is a technical mathematical term for this, but I am not a mathematician; "bijection", maybe?) What Cantor showed is that it is impossible to form an equivalent mapping between the integers and the real numbers. However you try and do this, you can always invent another real number that fits between the two that you have mapped. (It is a bit like Euclid's proof that there are infinite primes, in that respect.) The conclusion is that there are infinitely many more real numbers than there are integers. Even though there are an infinite number of integers. He went on to show that that are multiple levels of infinity which are not equal to one another. In fact, an infinite number of them. Some explanations below, hopefully you will find one that makes sense to you http://jlmartin.faculty.ku.edu/~jlmartin/courses/math410-S09/cantor.pdf https://www.cs.virginia.edu/luther/blog/posts/124.html https://en.wikipedia.org/wiki/Cantor's_diagonal_argument
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But you just said we do: you said (and the experiments show) that our mind makes the decisions. But that has nothing to do with free will. (And I am not going to start debating free will. I ... just ... can't.)
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But if that were to rule out a simulation on a grid, it would not rule out a simulation. And if it were to show a lattice structure to the universe, it would not rule out that being completely natural. Either result could be either a simulation or natural. But even if those were to find the results they claim would support a particular type of hypothesis, there is absolutely no reason to not just assume that "that is the way the universe works". Whatever results they get could be either a simulation or natural. Evidence that space is quantized on a lattice, or that things only come into existence when observed (or any other claimed evidence for simulation) may be consistent with the simulation hypothesis. But it can't rule out the alternative that we just live in a world that behaves like our idea of a simulation. Nothing can. There is nothing you can come up with that could only happen if the universe were a simulation. And nothing you can come up with that would be impossible if the universe were a simulation. Nope. It is the philosophical equivalent of solipsism or Last Thursdayism. Completely unfalsifiable by its very definition.
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That is not evidence in the scientific sense because it cannot be objectively measured or verified. No one has suggested you are a madman, nor has any reason to do so. Many people experience hallucinations without being "mad" (however you choose to define that). Many people experience spirits without being mad. Our mind is us. So we are making the choice for ourselves. (I don't believe this says anything about free will one way or the other.)
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I don't doubt you. There are many conditions that cause auditory and other hallucinations. In most cases, people are convinced that what they see and hear are real because, obviously, they are real to them. It really doesn't sound very interesting. I have experienced some strange hallucinations but I would not expect anyone else to be interested. It would be about as boring and annoying as people who insist on telling you what they dreamt last night. But you are not talking about science. You are just talking about your own personal experiences. These have little relevance to anyone else or the wider world.
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! Moderator Note You don't appear to have anything to discuss. And, apparently, you don't have time to discuss it. So: moved to a more appropriate location. Don't start any more nonsensical threads.
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It sounds completely typical of schizophrenia and other causes of hearing voices; right down to the belief that your experience cannot be explained by an "illness". It is good to know that you are not suffering because of the voices any more. ! Moderator Note Do not use this forum to start preaching your beliefs. That is against the rules. I don't think anyone here will be surprised to hear that. (I think there are some who would say that nothing in the bible is true.) Maybe they migrated to North America after the flood (I have a feeling you haven't really thought this argument through). But actually, as you say, the flood never happened. We know this from the geological record.
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This also highlights the importance of the double bond. That forces the relative alignment of the two halves of the molecule to stay the same. That is a key reason that isomerism exists (otherwise you could just rotate half the molecule and get to the other form).
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Are the weirdnesses of QM still regarded as mysteries to be resolved?
Strange replied to Alfred001's topic in Quantum Theory
The observer effect is a classical phenomenon, so I'm not sure it is relevant. What is a "GPU response"? Not sure how you can use common sense to explain something that is counter-intuitive (i.e. counter to common sense). If that were the case, it wouldn't be considered "mysterious". (Having grown up with these concepts, I'm not sure why they are considered so mysterious, anyway. I mean, come on guys, we have known about this for 100 years. It can't still be surprising.) -
The key thing is, can the two forms be made the same by one or more rotations. So in your G1, if you were to create an isomer by swapping the R and H at the top, then you could just rotate it by 180° to get back to G1. In G3, if you were to swap the orientation of the diether ring you can still rotate the whole molecule by 180° and get back to where you stated. But in G2 if you swap the R and H at the top, you can't rotate it to get back to the molecule you started with. You have to reflect it. In other words, you have a chiral pair (like a pair of gloves, rather than a pair of socks). If this is not clear from looking at the diagrams, then you need to build a model as Sensei suggests. (I bought a ball and stick kit when I was doing chemistry but never used it because I can see the symmetries immediately from the drawings. Which is bizarre because I have almost total aphantasia and can't tell left from right!)
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Are the weirdnesses of QM still regarded as mysteries to be resolved?
Strange replied to Alfred001's topic in Quantum Theory
Done. The "logical reason" is quantisation. Pretty much all the counter-intuitive ("mysterious") quantum behaviour is just a consequence of the quantisation of the wave and field equations. BTW: slightly off-topic, but relevant, there was a great BBC radio program on Paul Dirac this morning: https://www.bbc.co.uk/programmes/m000fw0p -
Great religious sicentists since the 20th century?
Strange replied to Alfred001's topic in The Lounge
Lots. The one who comes to mind immediately (just because he has talked a lot about his faith) is Paul Davies, the physicist. I expect most religious people just don’t make a big deal of it (probably true of most agnostics and atheists). There are a small number of anti-religious types who shout about religion a lot, which might give the impression that most scientists have similar views. -
Nervous system fatigue (weight lifting )
Strange replied to Keysi's topic in Anatomy, Physiology and Neuroscience
That always helps -
What is between 5/6 Pi and 17/18 Pi?
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I just tried Google translate to see if "arc of definition" meant something difference when translated into Russian. It doesn't seem to. So I have no idea what this means. Are you thinking in terms of an arc (presumably one subtended by the angle in question) that can be used to define the sine (or other) function?