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Fanghur

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Everything posted by Fanghur

  1. I have a question relating to supercritical fluids and their compressibility as compared to that same substance in liquid form. Let’s say we took 500g of water and turned it supercritical. Would we be able to then compress that fluid to a greater extent than we would that same mass of liquid water at the equivalent pressures? My instinct tells me no, but I can’t find any actual sources to back that up.
  2. So then the firecracker comparison was a bit of an exaggeration, but not by much. Either way, I guess Hamilton didn't bother doing the math.
  3. I recently finished reading Peter F. Hamilton's Commonwealth Saga (which I highly recommend to any Sci-Fi fans out there), and usually he's pretty good at incorporating actual scientific concepts into his stories when the plot doesn't require him to invent various Clarke-techs, but I was hoping someone with the know-how might be able to answer something. One of the technologies that humanity develops in the series is something they call a nova bomb, which is fired into a star to cause it to go nova. But the explanation given for exactly how it works is that once it gets deep into the star it emits some kind of quantum field that causes, quote, 'A volume of the star's interior the size of a super-Jovian gas giant to be converted directly into energy'. Now clearly this is an entirely fictional technology, but does anyone know how something like that would compare to an ACTUAL supernova assuming for the sake of argument that is possible? I don't know how to work out the math, but from what I do know about it, I would think that the actual effect the nova bomb would have would make an actual supernova look like a firecracker by comparison.
  4. Okay, so this is going to seem like a really odd post, and quite frankly I'm very depressed that I even need to make it, but there it is. So shortly after the movie 'Life' came out a few months ago, I had come across one of the scenes posted on YouTube. Specifically the scene where the alien, despite being completely boneless and seemingly only being about the size and thickness of a typical latex glove, only around 30 or 40 grams at most, manages to force a man's clenched fist open and proceed to essentially pulverize his hand. I had made what I thought would be a 'do duh!' remark in the comments section in the effect of enjoying how creepy the scene was but there's simply no way any organism that size could be that strong. But it's actually turned into an all-out flame war of people saying I'm an idiot and shouldn't judge an alien by the standards we would a terrestrial organism. In the story, Calvin is described as simultaneously being "all muscle, all eye, and all brain", and people seem to think that the 'all muscle' part makes it capable of seemingly defying the laws of physics. Anyway, I know perfectly well that this scene is impossible as portrayed, but could anyone who knows the physics that would be at play here and maybe some rough calculations tell me if I'm wrong about this? Or if I'm right, provide some rough figures to demonstrate it? I confess I'm not familiar with anatomy. https://www.youtube.com/watch?v=pzsoPzmn3qI
  5. I recently watched the new movie 'Passengers', and in the beginning of the movie, the starship has the misfortune of travelling through a cloud of space debris while travelling at approximately 50% of the speed of light. In the movie, the ship had some manner of force field to shield it, but I was wondering what would have happened in the real world if a ship travelling at that speed or greater were to collide with, say, a piece of debris the size of a grain of sand or a small pebble? I know that at those speeds, the impact would have a kinetic energy dwarfing any (possibly even all) weapons we have in our arsenal by several orders of magnitude, but what would actually happen at the moment of impact? Would it simply obliterate (or at the very least severely damage) the ship by creating an explosion comparable to an asteroid impacting a planet? Or would the effect be more akin to a bullet going through wet paper? That is to say, it would simply punch a hole clear through the ship like it wasn't even there and continue on? I'd imagine the answer would depend on how thick the ship's hull is, but I can't say for sure.
  6. Does anyone know whether there are currently any interpretations of quantum mechanics that are entirely deterministic? I was recently watching a debate between the cosmologist Sean Carroll and the Christian apologist William Lane Craig, wherein Craig claimed that there exist interpretations of quantum mechanics that are entirely deterministic. Now, frankly I would be tempted to just dismiss the assertion outright as an ad hoc attempt at rescuing his first premise from being falsified, because I've certainly never heard of such an interpretation if it exists, but I could be mistaken. My understanding is that even the most deterministic interpretation I'm aware of that hasn't been experimentally falsified by Bell's Theorem and the experiments that followed thereafter, namely the Bohm interpretation, does contain some elements of indeterminacy within it, including radioactive decay and virtual particles. Basically, does anyone know if I am simply ignorant on this topic, or was Craig being deliberately misleading?
  7. No, my beef is that what he is saying cannot in any logically intelligible way be the case, anymore than hitting a home run without a ball could be the case.
  8. If a proposition is logically self-contradictory, then it is by definition logically impossible. And saying that God causally produced an effect X, despite not carrying out any causal interactions on anything whatsoever (an affectless effect) IS self-contradictory, since effects are by definition the result of something being affected.
  9. What physicists mean when they use the term 'nothing' is not the same thing that philosophers mean when they use the term 'nothing', they're typically referring to some kind of quantum vacuum state. But even setting that aside, it would still have a material cause in that case, namely the quantum vacuum energy, though it might lack an efficient cause, which is really what people tend to mean when they talk about the 'cause' of something. Causality as we know it seems to simply not apply at the quantum level. What I am talking about is the concept of something CAUSING something else to come into existence with no material cause (i.e. to somehow bring about the effect that is something coming into existence, despite not exerting any sort of causal influence on anything whatsoever, including the 'cause' itself. And I have yet to find a single coherent explanation for how such a thing is even coherent; it's essentially like saying that God hit a home run without a ball.
  10. Okay, just to clarify, what I meant to say is that I am confident that even if a deity did exist, it WOULD NOT be capable of performing logically impossible actions. The autocorrect messed up.
  11. So, lately I've been spending quite a bit of time on William Lane Craig's Facebook page, and he is always espousing the idea of the universe being caused to come into existence ex nihilo, which is here defined as coming into existence with an efficient cause but no material cause. Now, to me this simply seems incoherent, because I cannot for the life of me think of a single coherent way in which this could logically occur. When we say that, for example, a carpenter causes a table to come into existence, we don't mean that the carpenter literally causally influenced the non-existent table such as to make it come into existence, what we mean is that the carpenter causally influenced pre-existing non-table material in such a way to cause them to become the table. Something which does not exist clearly has no potential to be influenced by a cause. Causality (at least at the post-quantum level) necessarily involves at least three things: 1) the efficient cause, that which causally influences (2) the material cause, which is that which is causally influenced, and the interaction between the efficient and material causes produces (3) the effect. And the material cause doesn't necessarily have to be 'material' in the sense of being made of matter; it could be anything. For example, Christians claim that God is composed of some kind of immaterial substance that they call 'spirit' (the adjective 'spiritual' in this case means "Made of or consisting of spirit". Whatever spirit is supposed to be, it is not made of matter as we know it, and yet it is still perfectly coherent to say that something causally affected 'spirit' to produce an effect. So what in the world does it even mean to say that God caused the universe to come into existence ex nihilo? It would mean that God didn't causally affect anything (including itself, since it is at least logically coherent to say that a god could be the efficient AND material cause of the universe), and the lack of causal interaction with anything resulted in the effect which is the universe coming into existence. Now look, as a metaphysical naturalist I don't believe that there are any supernatural deities, but I can say with confidence that even if there were such a thing, that entity would be be capable of performing actions that are logically impossible, as even the most ardent apologists will concede. Of course we also have the meaningless notion of time itself being CAUSED to begin existing, which since causality is itself a necessarily temporal phenomenon is itself logically incoherent. Thoughts?
  12. Lately I've been arguing with one of William Lane Craig's drone lackeys on his Facebook page. On the one hand this person is reciting the common mantra that 'infinities cannot exist in reality', and on the other hand he is claiming to hold to a classical view of space-time. When I pointed out to him that these two views are incompatible since if space truly is classical in nature then there would be an actual infinity quantity of spatial locations within space-time, he retorted that that is 'just a potential infinity, not an actual one!' Now, I think I know enough about calculus to be pretty sure that he is simply misusing terms here, but on the off chance that I am the one who is mistaken, I just wanted to ask for a second opinion. My understanding is that a potential infinity refers to the limit of a function over time that goes to infinity. For example, if someone asked you how many numbers can be counted (i.e. 1, 2, 3, 4, 5, 6... etc. ad infinitum), that would be an example of a potential infinity, since you couldn't actually count to infinity. However, if someone asks how any possible numbers actually exist, that would be an actual infinity. Similarly, if we assume that space-time is classical in nature (which assumes that space is infinitely divisible), the number of spatial locations that you could actually count, or attain through a function that continuously halves the number of points, etc. would be a potential infinity, but that if you asked how many spatial locations/points would actually exist given a classic view of space-time, that would be an actual infinity by definition. Am I more or less understanding this properly?
  13. I actually am not quite sure whether what I am referring to would even technically be referred to as 'holograms' per se. Basically, does anyone know whether or not the fully three-dimensional (as opposed to merely virtual three-dimensional) projecting technology seen in science fiction movies like Prometheus are possible even in principle? I'm referring to the common Sci-fi thing where a 3D image is projected seemingly into empty space/mid-air and a person can literally walk right through it without disturbing it in the least? Would that be holography or is that something else entirely?
  14. Ever since reading Lawrence Krauss' book 'A Universe From Nothing', I've been very curious about something. We have apparently determined that the universe is flat, meaning that if a light beam (or presumably any other object moving in a straight line) will never return to where it began. And we also know that space is expanding. To properly convey what I want to know, I'll use a thought experiment. Let's say you blasted off from earth at trillions of times the speed of light, such that you were moving through space faster than the space in front of you was expanding. And let's for the sake of it discount any time dilation effects. My question is, what would happen eventually? If the universe is finite and flat, would you eventually run out of space and literally fly into nothingness? Or am I thinking about it wrong altogether?
  15. But that doesn't mean that it doesn't actually have one.
  16. No you didn't, and in fact I specifically explained how they would apply even to that system of logic, or at the very least would not be violated by that system of logic, as they deal with dichotomies, and the system you named deals with trichotomies.
  17. That is why I specifically named the ones I was referring to.
  18. That is a different situation. Excluded Middle only applies to exhaustive and exclusive dichotomies in which there by definition can be no third option or hidden variable. And if you were to claim that 'true or false' were a true dichotomy, you would be incorrect. True or false is not a true dichotomy, 'true or not true', that's the true dichotomy. Therefore the Law of Excluded Middle still applies. And YdoaPs, what you said is certainly true apart from the false dichotomy that I pointed out, however, the laws of logic are also descriptive of the nature and behaviour of existence. It is the nature of all things that exist that they are themselves and not something else; the Law of Identity is our conceptual description of this necessary fact about existence.
  19. I was having a discussion with someone a little while ago and he made a claim that I found completely preposterous. He claimed that the laws of logic did not apply at the quantum level, which seems entirely self-refuting, as violating the laws of logic is by definition logically impossible. When I say the laws of logic, I am referring to the Law of Identity, which states that something is what it is and is not what it isn't (X = X), the Law of Non-contradiction, which states that in a true dichotomy of X or ~X, nothing can simultaneously be both X and ~X, and the Law of excluded Middle, which states that nothing can be neither X or ~X. I know a fair bit about quantum mechanics, and absolutely nothing that I know about it violates any of these laws; of course, quantum mechanics does indeed violate our notions of common sense and human intuition, but the three laws of logic are necessarily true due to the impossibility of the contrary. Did this person I was talking to simply have a misunderstanding of how quantum mechanics works?
  20. Okay, just to clarify, I am not talking about echolocation, such as it is, in humans. I am talking about echolocation in an animal where that is its soul means of 'seeing', like the Bioraptors in the movie 'Pitch Black', or even animals like bats on Earth whose primary means of navigation is by echolocation. Would they perceive the world via their echolocation in a way comparable to how we perceive the world using our eyes?
  21. I recently watched a documentary involving an interstellar mission to a fictional alien planet in which the majority of lifeforms on the planet perceived the world around them using a form of echolocation rather than eyes. Echolocation has always interested me, and one thing I notice whenever it is used in movies such as Pitch Black and TV is that from the point of view of the animals/aliens using it, it seems to produce an actual 'visible' image comparable to the way that we see using our eyes, albeit grainy and without colour. Is this biologically accurate or is it simply done for the viewers' benefit? Is it even possible for us to know?
  22. Lately I've been having some discussions with people online (theists), and one of the things that I find is almost invariably brought up on at least one occasion is that the Big Bang is supposedly, according to science, the absolute beginning of everything, and that this has been proven by something known as the Borde-Vilenkin-Guth Theorem. Now, I know that the latter comment is simply not true, as all three of those scientists have gone on record and clarified that their theorem only demonstrates that the expansion of our universe has a definite beginning, not necessarily existence itself. But as for the Big Bang itself, I was always under the impression that all science has been able to say about it thus far is that it is the beginning of the universe in its current state, not necessarily the beginning of our universe in the absolute sense of the term (discounting the possibility, for the sake of argument, that our universe is only one of an infinite number of parallel universes, which if I'm not mistaken recently had some evidence found for it). That is to say, contrary to what the Kent Hovinds of the world would have the public believe, I have never heard any cosmologist or theoretical physicist make the claim that the universe actually did emerge out of a state of complete nothingness (in the most absolute possible sense of the term), and I personally think that such a thing is most likely a logical impossibility. Is my understanding of the science more or less accurate? Or have I been misinformed?
  23. The other day I had all four of my wisdom teeth removed (two and a half were still under the gums, and I noticed afterward that my speech seemed to be slightly improved. What I mean by this is that for a while now I noticed that I had some slight difficulty making the 'roo' sound within a word, for example, the word 'truth' ended up sounding more like simply 'true', but now I no longer seem to be having that 'problem' quite as much, at least I don't think I am. Is there any reason that my wisdom teeth would be affecting my pronunciation like that? Or am I just 'hearing things', as it were?
  24. Does anyone know whether the common fundamentalist claim of something existing 'outside of space and time' has any meaning whatsoever given what we now know about the universe? I mean, to me, saying that essentially reduces to 'existing outside of existence' since existence is necessarily spacial and temporal. It seems to me like a clear violation of the Laws of Identity and Non-contradiction, which of course is logically impossible, but I'm not a physicist so I don't know for sure.
  25. Let's say that we eventually progress to the point where we are able to (somehow) produce huge amounts of antimatter, at least by today's standards, and we build an interstellar spacecraft to travel to Proxima Centauri. Let's say that using antimatter propulsion, along with several other propulsion types, we are able to propel the spacecraft up to a significant percent of the speed of light, say 50%. If I'm not mistaken, at those speeds it would take approximately 9 years for the ship to travel to Alpha Centauri from the point of view of those left on Earth, and ~2.5 years from the perspective of those inside the ship travelling at 50% the speed of light due to the time dilation effect. *Note that these numbers are not taking into account the deceleration period. Would I be correct in saying that when travelling at such speeds, hitting anything along the way, even something as tiny as a speck of dust smaller than the width of a human hair, would spell disaster for the entire ship? I'm not certain of the mathematics involved, but I would imagine that at those speeds the relativistic mass of that speck of dust, and its resulting kinetic energy, would dwarf any atomic bomb we have ever created. Would that be a fair assessment?
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