throng Posted November 4, 2008 Share Posted November 4, 2008 The universe is motion or transfer of energy. The expansion can't be into nothing so it is into itself. The dimensions of the universe are in relation to c. If the observer travels at c he takes no time to traverse distance so the universe is relatively very small. By that notion. expansion is relative to our slowing down in relation to c, which is in accordance with entropy. The universe's size is governed by the speed of the observer relative to c, so it isn't really expanding. It's an illusion we observe as we slow due to entropy. Link to comment Share on other sites More sharing options...
Edtharan Posted November 5, 2008 Share Posted November 5, 2008 The expansion can't be into nothing so it is into itself. This is a common misconception. A better way of thinking of the expansion of the universe is not to think of it like a balloon blowing up, but that the distances between things is getting bigger without them having to move (inertia = 0 and acceleration = 0). The balloon type analogy is often used because it is easier for people to think of Expansion like that (even though it is incorrect). Because it is just the distance between things that is getting bigger, and not that the Universe is blowing up like a balloon, it doesn't need anything to "expand into". Link to comment Share on other sites More sharing options...
mooeypoo Posted November 5, 2008 Share Posted November 5, 2008 You could also think about it as a raisin bread. When you finish preparing the dough with all the raisins inside, you let it rise in the fridge. As you do, the dough itself rises and the raisins "move away" from one another, but they don't actually move -- the space between them expands. Link to comment Share on other sites More sharing options...
traveler Posted November 5, 2008 Share Posted November 5, 2008 What do you mean they don't move?? The term "move" means that the object being measured using the standards of distance (meter), and time (second) traveled a distance in a time period (d/t). That IS MOTION. That IS what "move" means. Of course they "moved," every object constantly "moves." Link to comment Share on other sites More sharing options...
YT2095 Posted November 5, 2008 Share Posted November 5, 2008 what is the "Dough" rising into though, if not void space? the dough surely wouldn`t rise or the raisins get further apart in a sealed vessel! Link to comment Share on other sites More sharing options...
mooeypoo Posted November 5, 2008 Share Posted November 5, 2008 what is the "Dough" rising into though, if not void space? the dough surely wouldn`t rise or the raisins get further apart in a sealed vessel! well, same with the balloon in that aspect - the balloon itself "grows".. if you put it in a sealed box, the drawn dots won't move either, just like the raisin dough. It's not REALLY what's going on in the Universe, it's an analogy, YT. It's not very easy to think about the expansion of the universe, we're just trying to pick up the *closest* analogies so it will be easier. The point is that the "particles" themselves don't move. The space between them expands. It's not easy to think about space expanding (rather than particles moving), so we try to pick up analogies from things we do know to make it easier. Either think of it as a balloon or as a raisin dough, they're both similarly inaccurate, and yet similarly analogous enough to help us imagine it. 1 Link to comment Share on other sites More sharing options...
bombus Posted November 5, 2008 Share Posted November 5, 2008 Time is the expansion of space. Gravity is the effect of mass slowing time. I think... Link to comment Share on other sites More sharing options...
mooeypoo Posted November 6, 2008 Share Posted November 6, 2008 Time is the expansion of space. Gravity is the effect of mass slowing time. I think... I'm not sure I understand what you mean..? Link to comment Share on other sites More sharing options...
gcol Posted November 6, 2008 Share Posted November 6, 2008 Does he perhaps mean that if our notion of time depends upon the observation of movement, and unrestrained movement (within an unbounded environment) creates its own ever expanding and energy diluted space, and philosophically we don't like the idea of total entropy, we need gravity to restrain the expansion. Thus gravity could be said to restrain time as long as we measure time by movement. If energy, through entropy becomes mass, and mass begets gravity, I can imagine a closed-loop servo mechanism at work here. Apologies to Bombus if he did not mean something similar, and to anyone who is offended by my laymans terms. Link to comment Share on other sites More sharing options...
pioneer Posted November 6, 2008 Share Posted November 6, 2008 Energy moves from higher energy toward lower energy. A heated body will cool and not get hotter. Mass, on the other hand, due to gravity, goes from lower mass to higher mass. According to E=MC2 there is an equivalency of mass and energy. But the above observation has mass and energy going in opposite directions. Does this mean although mass and energy can interconvert, mass can not be composed of energy, directly, since gravity or GR makes this types of energy go toward higher mass-energy. In other words, if we assume mass was composed of confined energy, we could start with a vacuum (low energy density) and end up will all the mass(photons) forming a dense high (mass) energy zone. It goes cold to hot. To prove this we burn the mass in both scenarios. The final dense blob will display higher energy density. The energy will then flow the other way. Mass (energy), via gravity, acts like more what we would expect of negative-energy since it will go from lower to higher mass-energy density. In other words, if gravity increases negative energy, this would be the next logical step below zero energy. The direction of gravity would be consistent with lowering of total energy if mass was defined as negative energy. This is supported by the observation that mass can not move at C. If we normalize the C of energy as sort of a zero point, by staying less than C mass has to be negative at some conceptual level. We would have to add a lot of energy to dissociate the mass to substructure so it become pure energy again so it can reach C again. We use a different zero point and get two separate things with this energy paradox. Mass can be made to avoid the direction of gravity, but we need to add some form positive energy to cancel out the negative energy. We can add heat, entropy, etc., to overcome the negative energy called mass-gravity and make the composite go in the direction we expect of positive energy. But without any positive energy, mass defaults back to going in the opposite direction expect of positive energy. Gravity does not occur out of the context of mass but may simply be part of the negative energy affect. Using this standard, the expansion of the universe, to overcome the negative energy of mass-gravity, requires more positive energy. This could be generated by all the stars and the original positive expansion energy. An accelerated expansion only means the universe is burning hotter and hotter. This could be simply due to time allowing more and more stars to form. I am not saying this is the way, but how do we explain mass being energy, and this type of energy increasing energy density? Link to comment Share on other sites More sharing options...
gcol Posted November 6, 2008 Share Posted November 6, 2008 Pioneer: I am digesting that post. I think we are possibly on the same wavelength. Do we have to explain mass being energy? Not if we think of mass being potential energy, and energy being potential mass, perhaps. At any one moment either one or the other, but never both at once. Energy moving from higher energy to lower energy? How about phrasing it as moving from an area of higher to lower potential? The resolution of space-time strain caused by unequal potentials? That seems to be a desirable mechanism. (Enter stage left the panoply of strain-resolving charge carriers). As for the accelerating universe, and we are considering the possibility that mass slows time, then how do we know that time is invariant? If our standard model is based on invariant time, and in fact it is not, how would we know. Link to comment Share on other sites More sharing options...
mooeypoo Posted November 7, 2008 Share Posted November 7, 2008 (edited) Eh, okay, there are a few inaccuracies in this explanation, and i'm not sure if you misunderstand physics or if you just didn't explain yourself correctly, but those inaccuracies are quite important. Energy moves from higher energy toward lower energy. I'm assuming that by 'moves' you mean "changes state", but in any case that's completely inaccurate. Energy is conserved in a system, that's one of the laws of thermodynamics. That means that an object will not lose energy unless it has somewhere to transfer that energy to. For example: An object moving in circular motion, lacking any friction, would theoretically move like that forever, losing or gaining no energy. If there *is* friction (which is usually the case), then the kinetic energy is transferred out of the object and into the floor (or whatever it's moving in/on) in the form of, usually, heat. Energy doesn't *have* to change. In fact, it HAS to be conserved. If we have a "movement" of that energy (again, I think 'change of state' is more accurate, but that's not too bad), then it now exists in some other form. For sure. From kinetic it may have changed to heat, or from potential to kinetic, etc etc. But it doesn't just changes states on its own, and it does not do that all the time. A heated body will cool and not get hotter. That only happens because the object transforms its energy to the environment. For that matter, if you put that object inside a box that 'refuses' to accept the heat energy on itself, then the object will NOT cool down. That's the purpose of a thermos; to put the hot water in a place where the container 'refuses' to take the heat, therefore the heat stays in the water and the water's still hot after a long time. The only reason the water lose heat eventually is because the thermos is not perfect, it 'accepts' *some* of the excess energy (not a whole lot, and muuuuch much less than, say, air) and eventually the water cools. Mass, on the other hand, due to gravity, goes from lower mass to higher mass. Absolutely not. Maybe you mean a black hole, "eating" other massive objects is gaining mass (which is true) but mass does not go away with movement, or gravity. Hit a pingpong ball in space and it will continue on forever (theoretically, if it doesn't 'encounter' other objects), with the same mass. The only way it will gain or lose mass is if particles actively hit it (or 'join' it). According to E=MC2 there is an equivalency of mass and energy. No. There's a RELATIONSHIP between mass and energy and the speed of light, but they are FAR from being equivalent. Think of the equation F=ma, for example. That equation "simply" defines the *relationship* between mass, acceleration and force applied. It means that when force is applied on a body, it will gain acceleration proportional to its mass. That above equation does NOT mean that force and mass are equivalent. It just defines a relationship between them. Same with E=mc^2. That equation defines the relationship between energy, mass and the speed of light. It basically states that the energy produced by whatever-reaction on the mass would be propotional with the speed of light. Think of a Nuclear bomb; tiny amount of matter creates HUGGGE explosion (lots of energy). But something needs to HAPPEN to that mass so it will explode and produce such energy, it doesn't "just happen" and it doesn't mean that they're both the same. In fact, the equation *shows* they're not the same. E=mc^2. If they were equivalent, it would've been E=m. But the above observation has mass and energy going in opposite directions. ... ? What? Where? Energy has no direction, it's a scalar. Does this mean although mass and energy can interconvert, "Interconvert"? That's the same as saying radius and energy can interconvert because I can represent them both in the same equation. It's not untrue, it's just not quite leading to the conclusion you have next: mass can not be composed of energy, directly, since gravity or GR makes this types of energy go toward higher mass-energy. In other words, if we assume mass was composed of confined energy, we could start with a vacuum (low energy density) and end up will all the mass(photons) (ahem, photons are massless, hence they can move in the speed of light.) forming a dense high (mass) energy zone. It goes cold to hot. To prove this we burn the mass in both scenarios. The final dense blob will display higher energy density. The energy will then flow the other way. You will need to do a better job explaining this, along with some substantiation. I have no idea what you're trying to say, and it makes very little sense to me. Explain? Mass (energy) (mass is not energy) , via gravity, acts like more what we would expect of negative-energy since it will go from lower to higher mass-energy density. In other words, if gravity increases negative energy, this would be the next logical step below zero energy. The direction of gravity would be consistent with lowering of total energy if mass was defined as negative energy. This is supported by the observation that mass can not move at C. If we normalize the C of energy as sort of a zero point, by staying less than C mass has to be negative at some conceptual level. We would have to add a lot of energy to dissociate the mass to substructure so it become pure energy again so it can reach C again. We use a different zero point and get two separate things with this energy paradox. Mass can be made to avoid the direction of gravity, but we need to add some form positive energy to cancel out the negative energy. We can add heat, entropy, etc., to overcome the negative energy called mass-gravity and make the composite go in the direction we expect of positive energy. But without any positive energy, mass defaults back to going in the opposite direction expect of positive energy. Gravity does not occur out of the context of mass but may simply be part of the negative energy affect. Using this standard, the expansion of the universe, to overcome the negative energy of mass-gravity, requires more positive energy. This could be generated by all the stars and the original positive expansion energy. An accelerated expansion only means the universe is burning hotter and hotter. This could be simply due to time allowing more and more stars to form. I am not saying this is the way, but how do we explain mass being energy, and this type of energy increasing energy density? Meh, wordsalad up to here. Mass is not energy, they're both different definnitions of DIFFERENT physical phenomena. Of course they have a relationship between them, we discovered this relationship and can explain things with it, but they are *NOT* the same, they are NOT equivalent. Everything you say seems to stem from mass being energy, and since that's not accurate, I'm not sure I understand what you're trying to say here. Are you saying mass has potential energy? that mass can be 'converted' to energy? maybe, but then that doesn't quite lead to what you're saying above... I am not sure if you just explained in a way that I didn't understand you, or if you just misrepresent mass and energy definitions. Either way, you need to explain yourself again and, I would recommend, use some substantiations this time. If you claim mass is equivalent to energy, for example, you need to supply the proof for it, since it's not quite as obvious as you seem to think it is. ~moo Edited November 7, 2008 by mooeypoo 1 Link to comment Share on other sites More sharing options...
iNow Posted November 7, 2008 Share Posted November 7, 2008 Thank you for that, Moo. A much needed and well worded clarification, indeed. Link to comment Share on other sites More sharing options...
mooeypoo Posted November 8, 2008 Share Posted November 8, 2008 Thank you for that, Moo. A much needed and well worded clarification, indeed. Thanks, iNow, I tried, specifically since this -- Pioneer: I am digesting that post. I think we are possibly on the same wavelength. -- bothered me deeply. gcol, reading your question, you seem to have a bit better general understanding of mass and energy than pioneer (your attempt to rephrase his ideas to better fit physics is quite commendable), please don't let his misunderstanding confuse you. ~moo Link to comment Share on other sites More sharing options...
gcol Posted November 8, 2008 Share Posted November 8, 2008 -- bothered me deeply. Fear not, I was buying time. I hope my subsequent post full of questions hinted at my doubts. As a side-note, this thread and "Is relativity really necessary? Have helped me overcome my awkward squad aversion to the imposition of a cosmic (at least in our cosmos) speed limit. The phrase cosmic speed limiter comes easily to mind. Things would surely be too chaotic without it, and science does not like too much chaos. Link to comment Share on other sites More sharing options...
insane_alien Posted November 8, 2008 Share Posted November 8, 2008 science doesn't mind chaos as long as it is actually there. 999/1000 it just turns out to merely be slightly disorganized. Link to comment Share on other sites More sharing options...
gcol Posted November 8, 2008 Share Posted November 8, 2008 If you are looking for an argument over the various definitions of chaos, I am too tired. Might make an interesting thread, though. Why not start one? Link to comment Share on other sites More sharing options...
bombus Posted November 11, 2008 Share Posted November 11, 2008 I'm not sure I understand what you mean..? This is what I mean: http://www.timephysics.com/ This guy has some very interesting ideas. Can anyone pick any holes in them? Link to comment Share on other sites More sharing options...
Klaynos Posted November 11, 2008 Share Posted November 11, 2008 "believe in physics" We've had a thread on what is time, I seem to recall it addressed all the points on that site... which seems to be pretty void on physics content... Link to comment Share on other sites More sharing options...
bombus Posted November 12, 2008 Share Posted November 12, 2008 "believe in physics" We've had a thread on what is time, I seem to recall it addressed all the points on that site... which seems to be pretty void on physics content... I am no physicist so can you tell me, what laws of physics does this website transgress? The theories appear to answer many of the puzzles standard accepted physics does not. Link to comment Share on other sites More sharing options...
foodchain Posted November 13, 2008 Share Posted November 13, 2008 Would wave function collapse violate conservation laws? Link to comment Share on other sites More sharing options...
iNow Posted November 13, 2008 Share Posted November 13, 2008 I don't see how it would since a "wave function" is a mathematical concept, not a physical system. Link to comment Share on other sites More sharing options...
foodchain Posted November 13, 2008 Share Posted November 13, 2008 I don't see how it would since a "wave function" is a mathematical concept, not a physical system. I would agree I guess, but it seems the measurement problem still persists as some standing question. Link to comment Share on other sites More sharing options...
Royston Posted November 13, 2008 Share Posted November 13, 2008 (edited) Would wave function collapse violate conservation laws? I'm intrigued to know, why on Earth you think it would. In a nutshell, there's a probability of a certain outcome before we make a measurement, so supposing I fired an electron through a double slit, there's a probability of where it will end up on the screen. Once it hits that screen, we have an exact position, so the probability is reduced to one value (an eigenvalue.) So why would that violate, or have anything to do with a conservation law ? Here's another example, have a look at my sig. This assumes that some deluded numty thinks Elvis is probably still alive. So if said numty thinks they observed Elvis buying some brylcream in Walmart, the wavefunction collapses to Elvis being alive i.e [math]\Psi_{Elvis}(t) = \Psi_{Alive}(t)[/math]. Well, according to them. I'm not sure I follow iNow's reasoning in answer to your question. I don't see how it would since a "wave function" is a mathematical concept, not a physical system. But the wavefunction describes and is used to predict a physical system, I wouldn't class it as solely a mathematical concept. In any case, not meaning to sound rude, that doesn't really address the question. I would agree I guess, but it seems the measurement problem still persists as some standing question. What measurement problem, and what does that have to do with conservation laws ? EDIT: I don't have my textbooks for reference, but I can go into more detail later, if you wish. Edited November 13, 2008 by Snail Link to comment Share on other sites More sharing options...
iNow Posted November 13, 2008 Share Posted November 13, 2008 I'm not sure I follow iNow's reasoning in answer to your question. <...> But the wavefunction describes and is used to predict a physical system, I wouldn't class it as solely a mathematical concept. In any case, not meaning to sound rude, that doesn't really address the question. Basically, while the wave function describes the event, it is the event that must follow conservation laws, not the description of the event (sort of). I could very well be wrong, but I am of the impression that it is the event which follows conservation laws, that the description of the event must take them into account, but that the description wouldn't itself violate conservation. Am I too far off base? Link to comment Share on other sites More sharing options...
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