swansont Posted June 25, 2008 Posted June 25, 2008 I have good logic and common sense, but it doesn't agree with SR. That is my problem. Who said SR has to agree with common sense? The world we readily observe seems to follow a Galilean transformation. The Lorentz transformation reduces to this at low speeds, so we don't notice the difference until we measure carefully and/or go to extreme speeds. There's nothing "common" about this. It follows directly from the speed of light being constant. Apply your logic to that, and stop dicking around, pretending you don't understand basic things like vectors, etc. Or, if you really don't understand basic things like vectors, stop dicking around with relativity until you understand the fundamentals. In either case, though, there's a common action.
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 Who said SR has to agree with common sense? The world we readily observe seems to follow a Galilean transformation. The Lorentz transformation reduces to this at low speeds, so we don't notice the difference until we measure carefully and/or go to extreme speeds. There's nothing "common" about this. It follows directly from the speed of light being constant. Apply your logic to that, and stop dicking around, pretending you don't understand basic things like vectors, etc. Or, if you really don't understand basic things like vectors, stop dicking around with relativity until you understand the fundamentals. In either case, though, there's a common action. I don't know, who did say SR agreed with common sense? How can we measure the speed of light without a tape measure and stop watch standard?
Phi for All Posted June 25, 2008 Posted June 25, 2008 I have good logic and common sense, but it doesn't agree with SR. I don't know, who did say SR agreed with common sense?Troll infraction issued.
foodchain Posted June 25, 2008 Posted June 25, 2008 I've made up my mind that distance is measured with a tape measure, and time is measured with the timer. I have no clue of how to measure distance and time without those two items, do you? I am, however, open to suggestions. I am not beyond changing directions of travel, I just need to do a little accelerating to do that, though. Actually the concept of time can be related to lots of things, like the sun for instance. Also if you use a tape stick to measure something you are already using a logical system, much like what is being described to you, same goes for the clock. Plus measurement can be a lot of things, like the length of some royal persons arm span. Second you have to take all the variables into account, put them in the equations with the right units and then do the math to get the answer. Also the car thing would never be accurate enough i would think to measure such a situation along with a time and a yardstick, are you sure that both cars stayed exact for instance, such as one did not start a billionth of a second before the other one, could your timer tell you that? I think the basic idea here is that reference frames are relative? and that its the speed of light that allows your to discern ultimately other variables, not sure though so someone correct me if I am wrong please. here is a question for you, if two people witnessed a lighting strike one was to the left of it at 100 meters, and the other was to the right at 120 meters, who saw the lighting strike first and why?
Klaynos Posted June 25, 2008 Posted June 25, 2008 No, I am having extreme difficulty with SR, as it goes against everything I know to be true, as measured with a tape measure and stop watch. I think we need to try and help you understand classical relativity before we hope to get anywhere with SR. Which was the point of the split thread, but that didn't get anywhere, at some points you seem to know what we're talking about but when I tried to explain the difference between speed and velocity you said that you never brought up speed... But you did you just CALLED it velocity. I don't know, who did say SR agreed with common sense? How can we measure the speed of light without a tape measure and stop watch standard? You did. And if you want to measure the speed of light, give it a go during your little break from us. http://www.scienceforums.net/forum/showthread.php?t=33703
ecoli Posted June 25, 2008 Posted June 25, 2008 Yes, because I still don't understand it. And, we're glad to try and help you get it... However, since it doesn't seem like you're making much progress, this may be a sign that an internet forum won't be a good place for you to learn this information. There's absolutely nothing wrong with that, and I will do my best to keep the banter to a minimum, but you have to try and understand, that you don't seem to be learning anything from us, and having to answer the same questions over and over again gets annoying. That being said, perhaps you should take some introductory physics classes or at the very least, get a physics textbook and look at some websites. That way you'll have access to graphics and movies demonstrating the concepts we're trying to convey. It is a difficult concept if you've never thought about reference frames before and if you are new to this type of study. However it is indeed a study. Asking a string of questions isn't going to help you, because you don't seem to be familiar with the common jargon and basic concepts. This is NOT an insult. I'm just telling you that, if you really want to learn physics (and I think it's great that you do) than you'll do better in a classroom or more structured setting. Good luck.
Pantaz Posted June 25, 2008 Posted June 25, 2008 I've made up my mind that distance is measured with a tape measure, and time is measured with the timer. I have no clue of how to measure distance and time without those two items, do you? Ultrasonic distance measurment -- http://www.sonin.com/measure45.html (I have one. Very handy.) Laser distance measurment -- http://www.professionalequipment.com/laser-measuring/
swansont Posted June 25, 2008 Posted June 25, 2008 I don't know, who did say SR agreed with common sense? Try and differentiate yourself from the ELIZA program that ran on my Commodore PET 25 years ago. Please. You're passing the Turing test in the wrong way.
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 Actually the concept of time can be related to lots of things, like the sun for instance. With no knowledge of the current standards of the second and the meter, how would you measure the speed of light? here is a question for you, if two people witnessed a lighting strike one was to the left of it at 100 meters, and the other was to the right at 120 meters, who saw the lighting strike first and why? I have no idea, as the measurements are only a distance away from the lightning strike at impact. You only mentioned one point of the event, not a duration of the event.
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 With no knowledge of the current standards of the second and the meter, how would you measure the speed of light? http://www.scienceforums.net/forum/showthread.php?t=33703 You can measure it without knowing what a meter is -- you just need any system of measurement. Cubits will work, if you don't mind defining the speed of light in terms of cubits.
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 (edited) And if you want to measure the speed of light, give it a go during your little break from us. http://www.scienceforums.net/forum/showthread.php?t=33703 But she used a ruler, which is a standard of distance. She also did not actually measure the duration (time) of the event. I fail to see how she measured anything except the distance between two points using a ruler. I watched the video once, but it will not load now, so I don't quite remember all the details of how she arrived at the "time" portion, without already knowing the speed of light. Ultrasonic distance measurment -- http://www.sonin.com/measure45.html (I have one. Very handy.)Laser distance measurment -- http://www.professionalequipment.com/laser-measuring/ Those items use the standard of measures of distance and time. Without knowing and using the predefined standards, how would those items measure anything? http://www.scienceforums.net/forum/showthread.php?t=33703 You can measure it without knowing what a meter is -- you just need any system of measurement. Cubits will work, if you don't mind defining the speed of light in terms of cubits. I am not talking about the difference between a meter, or inch, or Cubits, I am talking about the established standard of DISTANCE. Sure, I could make up my own distance and call it whatever I want, but for you to understand what that distance is, I must tell you how many KHYUG's there are in a meter, no? Edited June 25, 2008 by Motor Daddy multiple post merged
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 You don't need to measure the duration of the event. The frequency of a wave equals its wavelength divided by its speed. Find the frequency (which is known for a microwave) and its wavelength (the two points on the chocolate) and you've found the speed. The point with SR is that I can make the same measurement while flying in a spaceship at Ludicrous SpeedTM and get exactly the same answer. Suppose we developed a microwave gun that could perform mooeypoo's experiment from afar -- aim the microwave gun at the chocolate from far away and you can perform her measurements. Then we go out in space and set up a space station with the microwave gun aimed and ready, then launch another spaceship at Ludicrous SpeedTM past the spaceship, the microwave gun aimed at it as it flies away. You'd assume that because the spaceship is going Ludicrously FastTM and the light is only going a little faster, the light would struggle to overtake the spaceship. But if I were sitting on the spaceship with the chocolate bar, I'd still get the same answer -- it's as if I were sitting still. Do you understand what I'm trying to explain here? (You don't have to see how that could happen. It's not supposed to make sense. I'm just asking if I was clear.)
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 You don't need to measure the duration of the event. The frequency of a wave equals its wavelength divided by its speed. Find the frequency (which is known for a microwave) and its wavelength (the two points on the chocolate) and you've found the speed. Speed? Does that have a time element already incorporated?
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 Yes, but it's something you're deriving. Frequency also has a time element (cycles per second).
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 Yes, but it's something you're deriving. Frequency also has a time element (cycles per second). And how was the cycles per SECOND determined?
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 Some fancy math determining the output from a given magnetron, I'm guessing. (At least that's how they'd design it.)
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 Some fancy math determining the output from a given magnetron, I'm guessing. (At least that's how they'd design it.) The point I make, and surely it's nothing personal with ANYONE here, as I respect all of you, but there was/is a standard of duration (time) already established, and ALL measures of TIME are taken according to that standard of duration.
swansont Posted June 25, 2008 Posted June 25, 2008 I am not talking about the difference between a meter, or inch, or Cubits, I am talking about the established standard of DISTANCE. Sure, I could make up my own distance and call it whatever I want, but for you to understand what that distance is, I must tell you how many KHYUG's there are in a meter, no? So do what they used to do. Hack a platinum+iridium bar to a certain length, and use that as your standard. Divide the rotation of the earth into a certain number of elements, and define that as your time interval. The actual standards do not matter for the concept. Get to the point.
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 Motor Daddy: I don't disagree with you. The trouble is that if I produce two devices that can measure time accurately according to the standard, and stick one on Jupiter (gravity affects time) or on a spaceship, it'll disagree with one that's been sitting on Earth. Time dilation is a real effect of motion, and it's not because my clocks are messed up by being flown at high velocity. I could build all sorts of high-tech clocks and they'd do exactly the same thing. Time dilation reflects reality.
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 (edited) So do what they used to do. Hack a platinum+iridium bar to a certain length, and use that as your standard. Divide the rotation of the earth into a certain number of elements, and define that as your time interval. The actual standards do not matter for the concept. Get to the point. That is the point. There is a STANDARD of distance and time already established. How do you measure the speed of light without already knowing the distance and duration (time) standards, a measuring them? How was the time measured without a standard second? Motor Daddy: I don't disagree with you. The trouble is that if I produce two devices that can measure time accurately according to the standard, and stick one on Jupiter (gravity affects time) or on a spaceship, it'll disagree with one that's been sitting on Earth. Time dilation is a real effect of motion, and it's not because my clocks are messed up by being flown at high velocity. I could build all sorts of high-tech clocks and they'd do exactly the same thing. Time dilation reflects reality. That's fine, then don't call it a second, because a second is a second is a second. If a clock runs slower or faster (which I never doubted), then it does NOT reflect the duration of a second. I am not trying to say relativity is useless. If something works, don't mess with it. But Distance and time have standards, and those standards don't change, regardless of if I break my tape measure or my watch runs faster or slower somewhere else in the universe. Edited June 25, 2008 by Motor Daddy multiple post merged
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 What does it matter? You measure the speed of something in units which are either predefined or you define. That's fine, then don;t cal lit a second, because a second is a second is a second. If a clock runs slower or faster (which I never doubted), then it does NOT reflect the duration of a second. How do I know which clock is right? You are assuming there's some absolute "second" that's the same everywhere. There isn't. Time itself passes at different speeds in different reference frames, making clocks seem to go faster or slower. The trouble isn't that we don't have a good standard of time -- it's that time doesn't play by simple rules. I am not trying to say relativity is useless. If something works, don't mess with it. But Distance and time have standards, and those standards don't change, regardless of if I break my tape measure or my watch runs faster or slower somewhere else in the universe. You don't have to break your tape measure, and the standards never change at all. They're the same. It's just that time (and space) change at high velocities.
Motor Daddy Posted June 25, 2008 Author Posted June 25, 2008 (edited) What does it matter? You measure the speed of something in units which are either predefined or you define. I just invented a new standard of distance and time. The unit of measure of distance is the length of my living room table, to be known as the unit of a TL. The unit of measure of time is the duration it takes me to walk to the mailbox and back, to be known as a MR. Now that that is established for all to use, can you relate? How do I know which clock is right? You are assuming there's some absolute "second" that's the same everywhere. There isn't. Time itself passes at different speeds in different reference frames, making clocks seem to go faster or slower. The trouble isn't that we don't have a good standard of time -- it's that time doesn't play by simple rules. If we don't have a good standard of time, then how do you know the speed of light? Edited June 25, 2008 by Motor Daddy multiple post merged
swansont Posted June 25, 2008 Posted June 25, 2008 That is the point. There is a STANDARD of distance and time already established. How do you measure the speed of light without already knowing the distance and duration (time) standards, a measuring them? How was the time measured without a standard second? That's fine, then don't call it a second, because a second is a second is a second. If a clock runs slower or faster (which I never doubted), then it does NOT reflect the duration of a second. I am not trying to say relativity is useless. If something works, don't mess with it. But Distance and time have standards, and those standards don't change, regardless of if I break my tape measure or my watch runs faster or slower somewhere else in the universe. The standards are defined under specific conditions. People who realize the timing standards have to account for their altitude when comparing signals, for example, because of the gravitational time dilation effects. If your watch runs faster or slower somewhere else in the universe, or under different conditions, how do you tell who is right?
Cap'n Refsmmat Posted June 25, 2008 Posted June 25, 2008 If we don't have a good standard of time, then how do you know the speed of light? We do have a good standard of time. Light also travels at the same speed in all reference frames, so it doesn't really matter if time dilation is occurring.
swansont Posted June 25, 2008 Posted June 25, 2008 (edited) I just invented a new standard of distance and time. The unit of measure of distance is the length of my living room table, to be known as the unit of a TL. The unit of measure of time is the duration it takes me to walk to the mailbox and back, to be known as a MR. Now that that is established for all to use, can you relate? If I faithfully realize this standard, but am moving at some speed relative to you, we well disagree when we compare times. We do have a good standard of time. Light also travels at the same speed in all reference frames, so it doesn't really matter if time dilation is occurring. Others should note that this was adopted only after many years of confirmation by experiment. There's no "circular argument" leverage here. Edited June 25, 2008 by swansont multiple post merged
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