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y_feldblum

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Everything posted by y_feldblum

  1. The number 3 is a concept. The number 3 does not exist as a metaphysical reality.
  2. Quark, gluon, proton, neutron, electron, hydrogen atom, hydrogen molecule, star, star system, galaxy, galaxy cluster, supercluster - all are things - all are bounded, all are aspects of reality. The universe is not bounded, in an epistemological sense. That is, when one speaks of the universe, one is not speaking of such and such bounded part of the universe, separate and apart from the rest of the universe which, for the moment, one is ignoring. One cannot speak of the universe as a thing, neither in any sense of the word universe nor in any sense of the word thing. There is no metaphysical universe thing, nor an epistemological universe thing. One can speak of the universe as - epistemologically - everything (but not a thing). Keep in mind that "entity" is actually an epistemological tool, a cognitive tool. The universe is actually an undivided whole - it is we who are observing it who, as our method of cognition, focus on certain aspects at a time and then on other aspects, as we find it necessary. Furthermore, it is an inversion of logic to speak of predecessor or successor universes, or alternate universes within a multiverse. Such sequences of words do not have any ontological meaning whatever. They have no cognitive status except for "mumbo jumbo." One cannot point to a predecessor, successor or alternate universe. One cannot acquire data from them. One cannot even speculate, because speculation requires a basic minimum of evidence to go on. One can only speak in tongues in a manner which almost, but not quite, sounds like comprehensible English.
  3. Completely wrong. Both theories are supernaturalist. That is, they pronounce the existence of phenomena for which there cannot possibly be evidence, phenomena completely outside of the universe, etc. In essence, they are theories of multiple realities, of of realities separate from our own. Logically and empirically, such a notion is a baseball bat to the head. The very same implications from Kant which, no doubt, also get on his nerves. Objectivism starts with observation of reality. The claim of multiple universes does not start with observation of reality.
  4. To speak of a thing is to speak of some bounded aspect of reality, mentally separated from the rest of reality. The universe, being everything, is not a thing. One ought not to confuse the universe with an actual infinity. The universe is not a thing. If it is indeed possible to go on indefinitely observing new things, it is still problematic to speak of the universe as an actual infinity. Nothing is an actual infinity: i.e., no thing is an actual infinity: i.e., no bounded aspect of reality, mentally separated from the unbounded rest of reality, is itself unbounded. The universe does not "contain" the things in the universe. The universe is the things in the universe. It is everything. Note that space and time are not things, but properties of things or relationships between things - properties such as location, extent, duration, motion, etc. It is impossible to observe space and time "in themselves" - we observe the above listed properties which things tend to possess. Space and time are unbounded, in the sense that a thing can be anywhere or anywhen, can have any extent or any duration. An unbounded space and time does not make for an "infinite universe," however. The universe is everything - not every potential location or potential time of things.
  5. Windows Explorer? Menu > Tools > Folder Options... > View > (uncheck) Hide extensions for known file types.
  6. Google Search: Result #1; Result #2. Apparently, rename a file with extension .cbz to have extension .zip and then unzip; rename a file with extension .cbr to have extension .rar and then unrar. 7-Zip is free software which can decompress .zip and .rar archives.
  7. Yes, general relativity says that an object moving solely under the effect of gravitation experiences no forces whatever and does not undergo any acceleration whatever at any given instant in time. And yes, obviously, this contradicts the everyday observation that objects do seem to accelerate and do seem to experience a force when moving under the effect of gravitation. And again, this phenomenon is easily and straightforwardly accounted for by supposing that spacetime is curved and that the trajectories through spacetime of objects moving solely under the effect of gravitation are geodesics: at any point or time, perfectly straight, but the result (in terms of, say, one's velocity) of moving from point A to point B depends on how one moves. Spherical geometry shows an example of what happens to an orientation in space as it is dragged along a sphere:if one drags the arrow from the equator to the north pole, the arrow points in one direction, but if one first drags the arrow 90 degrees to the left around the equator and then to the north pole, the arrow points fully in another direction. As you can see, the orientation of the arrow depends on its path through space along the surface of the sphere. In a similar way, velocity is an orientation in spacetime, and the orientation of an object moving along a trajectory depends on that trajectory. Newton accounted for the impossibility of observing local acceleration of an object moving in free fall by supposing that every gravitating object instantaneously and simultaneously affects the entirety of the universe ... and naturally did not offer a causal explanation, because such a proposition violates the principle that all of physics is local (that is, nearby objects affect nearby objects, and faraway objects affect each other only after time has passed so that whatever carries a force from one place to another has the time to carry it). In other words, Newton's explanation of why no acceleration could be detected was that the entirety of the universe was working against such detection. Einstein accounted for it more straightforwardly ... if one is comfortable with geometry in four dimensions and having curvature.
  8. I am going round and round making the same points: 1. Free fall is, locally (at any and every instant), unaccelerated motion. That is, an object in free fall feels no forces whatever. Free fall is motion affected only by gravity. This fact comes from observation and experiment, and the observation and experiment can be performed by anyone anywhere. 2. Free fall is, globally (when two separate places or times are compared), seemingly accelerated motion. Again, this fact comes from observation and experiment. 3. Newtonian physics can account for this only by supposing that gravity somehow permeates through space by some physical mechanism, which remains undetected and undetectable - in such a way as to simultaneously affect the entire universe. The conclusion of this approach is that no equipment in free fall can measure the effect of gravity as a force on another object again in free fall, because the effect is canceled out, but that point 1 is false and appears true by obfuscation. Newtonian physics is a good approximation at low relative velocities, but breaks down at high relative velocities. 4. Einsteinian physics can account for this by taking point 1 at face value, but saying that point 2 is false and appears true by obfuscation, and explaining them by means of a curvature of spacetime. Curvature of spacetime seems a physical oddity, but it is far from a mathematical oddity. Einsteinian physics is, so far as we know, a perfect match at low and high relative velocities. Newtonian physics accounts for all motions affected by gravity in one way, while Einsteinian physics accounts for it all in another way. Questions asking whether relativity account for this or that macro effect are pointless: yes it can.
  9. The feeling of standing on earth is the feeling of a force acting on you: the upward force of the Earth resisting your natural motion towards the Earth's center. The feeling of weightlessness is the feeling of nothing, i.e., of no forces acting on you. This of course has been tested repeatedly with instruments designed to identify and measure force. This phenomena of weightlessness is felt by astronauts hurtling through space from the Earth to the Moon, astronauts simply orbiting the Earth in the Shuttle, and astronauts in training on the Vomit Comet. When an object is in free fall, when it is moving in response to gravity and nothing else, no forces are felt. And yes, the Vomit Comet does move in a parabolic arc, first ascending and then descending for a period of 25 seconds, during which the occupants feel no forces. This is a real phenomena, tested and observed every day, and it requires an explanation. Newton's physics are inadequate to provide that explanation, because Newton considered gravity to act as a force and to be felt as a force. While Newton's physics do describe and predict the motions of objects to a high degree of accuracy when the objects move at low speeds with respect to each other, the same laws are inadequate to provide a correct physical explanation for the way gravity works. Time dilation is not what causes curvature of spacetime. Conceptually, the two [mathematical] phenomena are completely unrelated. Dealing with space and time together as opposed to separately is done, mathematically, in flat geometry; curvature of a geometry is dealt with independently of the relation between space and time. High relative speeds have nothing to do with whether objects in free fall feel any forces acting on them. Manifolds, Geodesics, Curvature and Local Flatness (General Relativity) - part of a FAQ on relativity theory, and (after skimming) seems to introduce well the concept of a locally flat and globally curved space. It is this phenomenon which accounts for motion which is always and everywhere locally constant and unaccelerated but which is globally accelerated (i.e., velocity changes). Recall that objects moving under the influence of only gravity do not feel any forces at all, and that an account of gravity which introduces forces is apparently wholly inadequate to explain gravitational motion. This is the (directly observable and testable) fact which led Einstein to hypothesize a curved spacetime.
  10. According to Wikipedia, M-theory is a unification of various approaches to string theory. Garrett Lisi's approach is not a kind of string theory.
  11. Are you interested in Ayn Rand's philosophical principles or in dictionary definitions?
  12. The paper was an attempt to unify all of physics into an extremely complicated mathematical structure known as E8. E8 is not a shape. However, it is possible to capture a small fraction of the information contained within E8 in some extraordinarily complicated graphs and even - but these depictions, unfortunately, are much more entertaining than enlightening. Garrett Lisi's paper contains no new physical predictions and is not based on physical evidence. It is based on a technique of capturing essential similarities between different kinds of equations. But his paper tends not to stand up to scrutiny.
  13. Existing and having identity independently of anyone's wishes.
  14. Which of your observations of reality, specifically, lead you to the conclusion that your observations are of unreality?
  15. Things exist, they have certain properties and not others at any particular moment, they act in certain ways and not others at any particular moment. That they change is but proof that reality is absolute.
  16. It is of course a fair question, and no I cannot offer a philosophical or metaphysical explanation of the nature of space and time and their relationship to our senses. I do know, however, that treating space and time as fundamentally similar, as aspects of a whole instead of as wholes in themselves, has various advantages: it accounts for observation and experiment; it accounts for observation and experiment without the necessity of proposing new entities which there is no clear conception of, let alone evidence for; it accounts for observation and experiment without suggesting that extents and durations are somehow "fluid" in that physical extents and durations depend on how they are observed. Ether theories propose new entities into existence for which there is no evidence, and various popularizations of relativity suggest that extents and durations are fluid, but the actual relativity theory does neither. In fact, the phrase "move between points" is not meaningful, neither on relativity theory nor on Galilean and Newtonian theory; the statement that "move between points" is not meaningful is part of the principle of Galilean relativity and is assumed in Newton's laws of physics, including his three universal laws of motion. Your trajectory through spacetime (your "worldline") can be measured. The length along your trajectory between any two spacetime events on your trajectory is called "proper time," and it is the amount of time which passes for you as you move between those events along your trajectory. Another person taking a different trajectory through spacetime, such that the same two spacetime events are present on his trajectory as well (i.e. you two meet up at two distinct moments) will experience a different quantity of proper time. The phenomenon is identical to that wherein you take a circular route between two cities and your friend takes the direct route: one of you will have traveled a shorter total distance.
  17. My point is not that the mathematics are accurate - they are, but that is a given. My point is that the mathematics describing the kind of motion of a body undergoing free fall - always and everywhere locally straight, free from the effects of any force or acceleration (by observation and experiment), but globally curved, seemingly moving in accordance with force or acceleration (also by observation and experiment) - is the exact same mathematics which describes a curved space. The mathematics of curved spaces (rather, general spaces) perfectly describes the motion of bodies influenced only by gravity. It is very difficult to make the case that there is something else there, undetectable thus far, which masquerades in the mathematics as a curved spacetime. A pervasive material permeating all of space and transmitting gravity is quite likely to have a very different mathematical description: incompatible with and contradictory to the mathematics of curved spaces. But there is as yet no proposed mathematical description of such a pervasive material, to my knowledge, so no comparisons can even be made. Note that the mathematics describing an object undergoing force or acceleration in a noncurved (specialized space) are vastly different from the mathematics describing the global movement of an object experiencing only the effect of gravity, and the differences in the mathematics are to be found again represented in observation and experiment. In other words, curved spacetime (rather, general spacetime) without forces is a good description of gravity, i.e., in accordance with observation and experiment, while noncurved spacetime with forces is a poor description of gravity, essentially Newton's description, which is not in accordance with observation and experiment (namely, the observation that falling objects feel neither force nor acceleration). The source of curvature in spacetime is, as asserted in Einstein's theory, material. This particular deduction from the mathematics has predicted very many astronomical discoveries, such as binary stars, pulsars, and black holes. By all accounts, general relativity is a very successful theory: its accurately describes the way bodies move in response to the presence of other moving bodies. It does leave unexplained the mechanism by which material effects curvature of spacetime, although the mathematical relationship between moving material and curvature of spacetime is completely specified. This lack of mechanism makes the theory suspect and difficult to swallow. But it does not change the fact that the assertion of a pervasive material permeating the universe is unable to account for the motion of material in the presence of moving material.
  18. As Einstein observed, objects in free fall (i.e., objects moving under the effect of gravitation and only under the effect of gravitation) experience no accelerations, no forces; yet we observe them accelerating as though forces were acting on them. This is an indisputable observation of fact (which you're not disputing). As Einstein observed, a mathematical description of this phenomenon is that the trajectory of such an object moving in free fall is the trajectory of a locally straight yet globally curved line. Lines are locally straight and globally curved in curved spaces. Therefore a mathematical description of this phenomenon is that spacetime - the spatiotemporal relationships between entities - is curved. Now let me invert your perspective. It is the general case that the spaces which mathematics deals with are curved. It is sometimes a useful special case to consider spaces which lack curvature. We observe, with our naked eyes, no curvature of spacetime. But we know from mathematics that the general descriptions of spaces account for curved as well as noncurved spaces equally, treating noncurved spaces as a useful special case. And we know from observation that mathematics would suggest that spacetime is curved, and again mathematics suggests where to look to find evidence of this curvature - that is, bodies which have followed curved paths. And lo, we have found such bodies, moving in exactly the trajectories which the curvature explanation of free fall would have them move. Do we have evidence that space is noncurved? Actually, no. We have mountains of evidence that, in all contexts observable and knowable before the 20th century, that no curvature was ever observed or expected, because velocities had not yet become so high, and observations had not yet become so precise, and the theory of electromagnetism had not yet reached the point of contradiction with Newtonian physics. Curvature of a space has nothing to do with the observed curvature of the surface of a body. Space is not a thing. Curvature means that locally straight lines are not globally straight - lines parallel here may not be parallel there, parallel trajectories a certain distance apart here may be farther apart or closer together there, etc. Is this the correct explanation. That's a good question. Mathematically, it fits. The correspondence is there between free fall and locally straight yet globally curved lines. The theory based on this mathematical explanation of free fall has been very successful. The theory neglects to answer, of course, by what mechanism the presence of matter induces curvature of space, and that is a serious flaw. The quantitative description is there, but not the causitive description. However, the solution is not to look for things which are not there.
  19. Special relativity uses geometry as its tool, just as Newtonian physics did. Geometry allows the physicist to abstract from what in particular he is studying to the general laws which describe all motion. General relativity attributes seemingly curved or accelerated motion to the curvature of space (note: not the same meaning as when one speaks of an object being curved) and the fact that straight-line, unaccelerated motion in a curved space seems curved or accelerated (which is true independent of Einstein's interpretation). Einstein argued that matter curves space - and it immediately follows that other objects moved through curved space in straight, unaccelerated motion, and that their apparent curved or accelerated motion is caused by the curvature of space, which is caused by the presence of matter. Obviously, the interesting part is Einstein's argument that matter curves space, and that matter is therefore the cause of seemingly gravitational motion in a universe where gravitational motion does not exist (by observation - this is the part which has to be explained somehow). Obviously, it's a philosophically deep question. But treating the use of "curved" here the same as the use of "curved" when describing everyday objects only obscures the argument.
  20. Why the hostility to the deep focus on geometrical methods in Einstein's theory, especially considering there exists the same deep focus on geometrical methods in Newton's theory?
  21. The video does a decent job describing the general understanding of quantum tunneling. An understanding of probability and statistics as well as an understanding of potential energies would help significantly in understanding what that Wikipedia article means, but the video is a good start.
  22. "We definitely know when the particle is inside the nucleus of a radioactive atom, and we can clearly tell when the particle spontaneously "hops out" of the nucleus." Not according to the proponents of Quantum Mechanics.
  23. Hah. An accessible resource on quantum physics. It doesn't exist. That's why I know only very little about it quantum physics. In your argument, you again reify the void, that is, the lack of entities in any particular region. Without reifying the void, and starting with perceptual observation, how does one come to the philosophical conclusion of a full plenum - that is, a universe with no empty spaces between entities? Personally, starting with perceptual observation, I observe that there are entities here and here, but I do not see anything in between. Being somewhat of a scientist, I design and perform experiments to test for the existence of other entities invisible to the naked eye, but, no matter what I try, I find none. I induce mathematical formula which describe all the observed phenomena, and which do not rely on any other entities which I have not yet observed, and these formula are very accurate. The conclusions is, of course, that there is not a full plenum, that there are regions of space (without reifying space) in which there are no entities.
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