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Everything posted by Robonewt
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Did the Hafele-Keating Experiment prove anything? In the experiment the moving Clock was travelling at height and speed at the same time, is there any way you could differentiate how much of the effect was due to the speed, and how much was due to the reduced gravity at height. It could have been that there was no effect due to speed, only due to the reduced gravity at height. Also, as you say, it didn’t necessarily prove that the rate of time changed, only that the mechanics of the clock was affected. Could the effect also have been due to the clock travelling across the magnetic field of the Earth? Could or have other experiments been done? such as flying north south to discount any magnetic field effects or floating a clock stationery at 10,000ft. Is there any other clock type that could be developed to show the effect isn’t only relative to atomic clocks? Practically, nothing would change, even if the effect is only mechanical, we would still need the relativity equations to allow the atomic clocks to be of use, all that changes is our reasoning behind it.
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If light speed is always C how do rangefinders work?
Robonewt replied to Robonewt's topic in Relativity
Yes on Earth everything is in a closed system, everything is spinning around the Centre of the Earth, Which is spinning around the centre of the Solar system, which is spinning around the Centre of the galaxy. And because everything is travelling at the same speed to start with, you can ignore these speeds in our calculations on Earth. That makes sense, and if light follows the same rules as everything else, that is fine. In the closed system of Earth, the speed of light will also be measured at C. Also because it is a closed system, it can be said that the mechanism that emits light always emits it at C relative to the Emitter. However, anyone else looking in from outside, would have to consider the relative speed of the emitter to themselves. The problem I have is where it says that light is measured as C regardless of the frame of reference. By saying that you are taking it outside all frames of reference and as such would have to include somehow all the relative speeds. If someone was standing at the centre of the galaxy watching the rangefinder at work, then the relative speeds of the solar system round themselves, the Earth round the sun and the spin of the Earth come into play. They would measure a different speed of C that would vary depending on the time of the experiment, but they could calculate the same speed of C as us in the closed system. Relative to them, the light is not travelling at C. However using what they know about the speeds of the various components they could calculate the value of C relative to the emitter. Also a speed change could cause an apparent, frequency or wavelength shift, as you are measuring the signal end on, but I suspect that statement will be knocked down by saying the maths prove otherwise. -
Range finders can measure distances up to 5km to within an accuracy of +-10cm if reflectors are used. http://www.onsitetools.com/measuring/laser/surveying/detail/5000/ If a system were set up to measure a known distance of 5km in a north south direction somewhere using a reflector. How does the laser return to the emitter? The sun and the earth with it, is travelling around the galaxy at 250,000m/s. http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Speeds.shtml Light travels at approx 300,000,000m/s Light takes 1.667e-5 seconds to travel 5000m (t=d/v, t=5000/300,000,000) The Earth will have travelled 4.2m in that time. (d=vt, d=250,000x1.667e-5) For the laser to return to the emitter it must travel 10km, which works out at 8.4m in total that the earth will have moved. If you assume the laser does not carry the momentum of the emitter, and If you did the experiment when the Earth was in front of the sun on its orbit, then the laser would likely hit the ground before it got back. If you did it when the Earth was behind the Sun in its orbit the light would likely shoot past 8m above the emitter. With the Earth running parallel the laser would pass to the left or right. Surely the only way the Laser can work over such distances is that it carries the momentum of the emitter, but this could mean a variable speed of light.
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How about this for a paradox. You go back in time, but rather than kill your grandfather, you go visit the young Einstein and explain to him the theories of Relativity, which you have learnt from his teachings. The question is, where did the theories come from? He would not have known them had you not gone back to explain them, but you would not have been able to teach them to him if you had not learnt them from his teachings……..
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If phase 2 causes a difference in the ages, why doesn’t Phase 1? In both, Adam experiences acceleration, why does one cause a different effect than the other? If the effect does not occur under constant motion, why does the size of time difference also depend on the amount of time spent at near light speeds?
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Are you saying that the difference between the two clocks when Betty returns is dependant only on the acceleration that Betty experiences and not the length of time she travels at a high but constant speed?
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Some questions If the two observers see the same effect (Clocks running slow) when Betty accelerates away from Adam, then they will surely both see the same effect (Clocks running behind but at a faster rate) when Betty accelerates back towards Adam and also the same again through the deceleration processes. Visually there would be no way to tell who was moving, so the experience should be equivalent for both. How does this create a difference in the clocks when they return? If you want to include the force as a distinction then it has to be valid in all accelerations and decelerations and so would affect the experience had by Betty in all instances, losing the simultaneity in every case. Secondly, what would A or B actually see with regards to the clocks? If the speed of light is always C regardless of the frame of reference then it would always take 1 second of local time to see the second hand move on the other clock. You would not be able to see the apparent change of rate of the clock, because light would always bring it to the observer at the same rate as it was sent.
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So What happens if you take your money from your monthly wage out of a useful hole in the wall, pile it in a safe place and burn it? The money is destroyed, you have less of it, but no one has more. The total sum of money in circulation has been reduced.
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Let me start by saying I am not a physicist, I am just interested in the theoretical ideas of science. I find it amazing that we still have problems defining light, is it a particle, a wave, both or neither. These thoughts I have presented here just look at it from a different angle. I am also no mathematician and so apologise before hand if my explanations appear very simplistic. Ok with that said, let me begin. Light is always compared to water and sound for its wave properties, but considered as a particle because it can travel across a vacuum. Perhaps we should take the comparison closer instead of further away. Let me expand…… Waves on water are caused by vibration of a physical body within the water, this causes that kinetic energy to be transferred from one particle of water to the next creating a wave that moves along the water. Sound waves follow the same process, only the vibrations are sent through the medium of air rather than water, so each particle of air passes the kinetic energy onto the next transferring the energy along, the wave shape is held by the bonding between the air particles. Now I think that the problem we have when looking at light stem from our trying to view it as a wave and a particle in a single entity, rather than a medium of particles that are carrying a wave, just like water and air. If you take the photons themselves as the medium of particles, just as water or air is. The wave effect is actually the vibrations of the source travelling through the medium of the light particles. The only difference is that the light particles have a velocity as well. Water, air and even solid matter consist of particles that are held together by a force of attraction. It is this attraction between the particles that holds the body of whatever the medium is together, the stronger the force the more dense the body and the more solid. When one particle moves it affects the particles around it, thus when a vibration moves the first it affects the next which affects the next. Light is no different. When an object emits light it does two things, firstly an energy is released in the form of (for arguments sake) photons. At the same time, the source is vibrating. This motion is passed into each photon as it is emitted. Each photon is bonded to the preceding, following and surrounding photons, this transfers the kinetic energy of the vibration along the path of the photons creating a wave. As the medium is moving outwards the wave is carried along with it. A similar effect would be seen if you were to shoot a hose of water out into space all the while moving the nozzle up and down. The water would travel across the vacuum at the speed it left the hose, and it would also carry the wave of kinetic energy caused by the vibrating movement of the hose. The wavelength of the wave would relate to the vibration of the object emitting the vibration. For an object to emit white light it must have enough electrons to vibrate at the various rates to produce the various wavelengths. The next bit is just a guess at the mechanics of atoms emitting light. I think that each of the electrons would be vibrating at a constant rate, but each electron would vibrate at different speeds to the others. As electrons are excited they build in energy speeding up, until a maximum is reached and the friction between them and the nucleus emits electromagnetic energy and the electron drops back to a closer orbit and velocity, starting the cycle again. The wave transmitted on the back of the energy would be relative to the vibration rate of the electron. Because the mass is so small the photons will continue to move in the direction they were first sent at constant speed because there is no force large enough to inhibit them. To summarize, I believe light can travel through the vacuum of space because it consists of particles of electromagnetic energy that are carrying the wave generated by the vibrations of the electrons at source. Its speed is only constant because it encounters nothing in the vacuum to absorb its energy or affect its path, with the exception of extremely high gravitational pulls from masses of extreme size, enough to affect the tiny mass of the electromagnetic energy. A change in speed as the particles entered a new medium would not alter the wavelength, but if the particles have to work against an external gravitational force, some energy would be converted to mass and so the wavelength would change slightly (red shift effect?). Another way to look at it would be to use water to replicate the effects of a light emitter. Consider a large sphere covered in tiny holes. Take the sphere into space away from any gravitational effect and fill it with water. The water would just stay at rest within the sphere. Now add a water supply that pumps water into the centre of the sphere and start it pumping. The water would be pushed out evenly in every direction at a constant speed, the speed of the water pump. Now loosen the fixtures holding the sphere so that it vibrates. The water would continue to be emitted in every direction at uniform speed, but it would now be carrying a wave, generated by the vibration of the sphere. This wave would be transferred across the vacuum of space until it received sufficient outside force influence to deflect it. I think light and electromagnetic waves are just very efficient versions of this effect. The emitter constantly pumps out electromagnetic particles of various energy levels, all the while vibrating with a frequency generated by the electrons moving around the nucleus. To take this further, if all electromagnetic particles have an equal total mass that is the sum of its energy and physical mass, then the higher the energy the smaller the physical mass, this would allow for higher energies of electromagnetic particles to pass through denser mediums, hence light can pass through water but not flesh, X-Rays can travel through flesh but not bone and Gamma Rays can travel through everything. Denser mediums have smaller holes between particles, so it requires smaller physical mass to pass through the holes. Maybe when poets describe an ocean of light they are closer to the truth than they realise.
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This is the heart of it. For the clock travelling at speed to have ticked less, means it has experienced the same amount of time as the stationery one, but the mechanical means of measuring the passage of time was compromised by the motion of the clock. This is where special relativity fails to differentiate between illusion and reality. You are saying both clocks have experienced the same amount of time, but the faster is inaccurate due to the effects of its velocity on its mechanics. Its not a real time difference just an illusion The current interpretation of Special Relativity says that because the faster clock shows a slower time it has travelled slower through time, it’s not an illusion it’s a real time difference. So your theory is only possible if Special Relativity is wrong.
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The point is you do know what all three are, because C is a constant velocity which is equal to 300,000,000 m per second. Because you know all three, any two can define the third.
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How is a ratio of 196,850,393:1 equal to 300,000,000:1? Yes the speed of light is constant regardless of the units used, but the value we assign it isn't. We could explain the length of a metre by giving them a pole a meter long. We could explain a second by showing the atomic clock and how it works. The only way we could describe the value we use to describe the speed of light would be to show them our metre, show them our second and they could then compare it to their unit of length and time to see how our speed of light value compares to theirs.
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I know it isn't how it is defined by science, I was just saying that you could define it that way. If all three parts are constant for the situation you could use any two to define the third. My point was that seconds and metres can be defined by alternate methods where the value of the speed of light is reliant on the value previously defined for the other two.
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Light isn’t a constant, the speed of light is a constant. That is for a second as measured by an atomic clock, light will cover a measured distance. It is travelling at a fixed constant speed from A to B. The only way special relativity works is for light to experience a different rate of time. That is, if light were carrying an atomic clock then it would not witness any change in the clock as so would experience no time, as it experiences no time it cannot lose energy and so can travel across a vacuum. For us as observers though we witness a number of ticks in our atomic clock and so for us an amount of time has passed. This would seem to suggest that the rate of time you experience is dependant on the speed you are travelling. Multiple rates of time mean time travel. If C is just a constant number then it has no relevance to anything and is just a figure that is used to give results a magnitude. Your whole argument fails if we choose to no longer define the metre using light. The circular definition disappears and the speed of light, whilst always the same, is a magnitude is dependant on the length we define as a metre. It is not an absolute constant, just constant relative to our definition of the metre.
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If time was like a river you could go up it, down it or travel along it at different rates. I was trying to say that time passes at the same rate whether motion happens or not. If no one existed to count anything would time no longer exist? Just because something is not recorded does not mean it doesn’t happen. With regards to the traveling through temperature, yes it is a figure of speech, but what I was trying to say is that heat has a direction; you can get hotter or cooler along the heat scale. Ok it’s a measure of the amount of radiation, but you do travel through all the amounts in between, you can’t just jump from one temperature to another. How else would you describe it other than a motion. I was trying to show that time doesn’t relate to heat in the same way. You can only go along with time and you can only travel at a certain rate, whereas you can change your temperature up and down at varying rates. Heat can be touched, experienced and changed. Distance can be seen, experienced and changed. Time can be experienced, but not touched and not changed.
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Your analogy is flawed (a strawman) because you have only provided only one defined quantity, and in reality we have two. Both c and the second are defined quantities. All three components could be defined from the equation Speed of light is 299,792,458 metres travelled every second 1 second is the time it takes light to travel 299,792,458 metres 1 Metre is the distance travelled by light in 1/299,792,458 of a second because, for the situation, all three are fixed values. However, we could also define the second using the atomic clock and we could define the length of the metre in the traditional way. Can the speed of light be defined any other way than as a result of dividing known a known length of the metre by a known value of the second? That we have chosen to define the metre as the distance travelled by light in a set period of time is fair enough. And I am sure it helps when calculating results. All I am saying is that by doing so you open up this argument of a circular definition that Farsight is using to base his premise on.
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Farsight :- from your original essay This is why I thought you were trying to take time out of all the equations.
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The fraction was chosen because the metre was the base unit of all length calculations, if any other fraction was used, and the term called for example the litemetre then all the formulas would have to be rewritten. But they would still have to be compared to the metre for everyday use creating an unnecessary complication. It could cause problems if the constant of the speed of light in a vacuum were wrong, however the concept isn’t implausible, there are already theories that think the speed of light is slowing over time. In order to define the speed of light you had to know how long a metre was in order to calculate the fraction you wanted to use to define a metre. You have to know that light takes 1/299,792,458 of a second to travel a metre in order to say that a meter is the distance it travels in 1/299,792,458 of a second. The problem lies in that you are using a velocity to define a measurement when the measurement you are trying to define is a component of the velocity. Try setting the equation up in excel, type “=B1*299792458/A1” in cell C1, then type “1” in cell A1 and finally type “=A1/C1” in cell B1. Excel will tell you it can’t calculate the result because it contains a circular reference.
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Absolutely, I was just saying it is difficult to create clocks that are accurate to the base time, not impossible. I was just saying there is always a chance that the place a clock is taken to has some aspect previiously unencountered. I don't mean to offend, I understand the area of atomic clocks is something you understand in great detail, much more than me, after reading your profile. I still disagree to an extent. The Definition of the speed of light is dependant on the meter being a known constant measured by a different means. If we had originally defined the metre as say one tenth the height of nelsons column then when we came to measure the speed of light we would have arrived at a different magnitude of constant C, because it was defined using distance over time with the distance measured in metres, so one metre would equal approx 5.6 of our metres as we know it. C would then have been 5.6 times smaller. We could then reverse engineer the definition to redefine the metre. And the circle would begin again. If we were to discover that the speed of light in a vacuum was slightly wrong, does this then mean the length of the metre would change? or would the speed of light be redefined? But if the speed of light was redefined then the definition of the metre which is dependant on the speed of light would need to change...... Both definitions rely on each other so which do we change if one is found to be inaccurate?
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My apologies swansont regarding the atomic clock, I hadn't fully read into the mechanics, but my point is that the clocks operate using mechanics, that are possibly susceptable to other energies that could affect the mechanics should the clock be moved from one location to another. Because of the very high accuracy of measurement this could result in one clock running at a different rate to the other. I was just trying to losely explain how difficult it is to create a base time that can be taken anywhere which we can then rely on as being as accurate as the original, but as I said this is to do my own ideas. With regards to the speed of light verses metre derivation or definition. The speed of light is defined as a speed of metres per second, therefore it is reliant on the definition of the metre, which is defined as the distance light travels in x amount of time which means it is reliant on the definition of light and so on. The definitions are circular. It is this circular definition that Farsight is using as is basis for his argument to banish time from the science books. <quote>A wavelength is a distance, a thing like a metre: “The metre is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second...” And a velocity is a distance divided by a time. So: A period T is a distance divided by a distance divided by a time. That’s a another period, another time. OK, so that definition of time is circular</quote> You do need a bootstrap to start from, and that is fine, I was merely commenting on his use of the circular definition. The metre used to be defined as "as 1/10,000,000 of the distance from the equator to the north pole through Paris" which would prevent Farsight from creating the circular definition.
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I am going to return to the beginning and comment on the original essay, taking each point as I get to it. I will first tackle the perception theme. I am not quite sure how you are relating this to the rest of the argument. The various examples you use don’t quite mix with each other. The colour example indicates how results we see cannot be assumed to be accurate when viewed through the naked eye because the brain makes assumptions and takes short cuts to interpret the experience as efficient as possible. It does not show that colour is a perception, because the colour is grey, even though your brain fools you into seeing yellow. If you put a yellow box on screen with no colours around it you see it as yellow, because it is yellow. The heat example is just showing that we can experience something without having to know the mechanics of how it works; heat is the term we use to describe an experience. Considering pressure at sub atomic levels, the only reason it is derived, is because we don’t have the technology to measure it. For the kinetic energy example, if you are moving and the ball is stationery then you have the kinetic energy it isn’t nowhere as you state. I happen to agree with you that it doesn’t exist as an entity in the same vein as electromagnetic energy, but is just a mathematical tool. Sound as heat is the term we use to describe an effect, the effect is there, just because we know the mechanics, does not mean sound does not really exist. Now to get down to your mathematics regarding time. The problem you are having is down to a problem that physics has with maths, in that they often use a definition to define a measure that itself was defined by the original definition. The meter is now defined as the distance light travels in a period of time, but the speed of light was defined as a distance over time where the distance was measured in meters. This is a wonderful circular definition. The problem is that the metre is the term we use to define length, so anything that uses length in its definition should not then be used to define the metre. A meter is a meter, the only way to truly define it would be to decide a base length and then everything else has to be compared to that physical length. All dimensions are terms that have been created by the human race in order to try and make sense of the universe by breaking it into manageable bits. This is true for length width height and time. The same could be said of pressure, temperature and other dimension. If you travel from zero degrees to 50 degrees over 2 seconds, you have still gone through a motion, just one of temperature. Fundamentally dimensions are just the terms we use to describe a change from one state to another. I do partly agree with you in that time is different from other dimensions, because like you, I don’t think time can be travelled along like a river. Time will pass if there is movement or not, If nothing happens, you don’t move from a to b, your pressure, temperature and bank account stay at zero for three days, three days will still have passed. Even if your atomic clock has stopped time will still pass at the same rate. The difficulty is in defining a base time. We do this by measuring the rate of caesium atoms hitting a Geiger counter when excited by an electromagnetic field. However this can only be true for a physical location, for as soon as you move it to a different location the environment may well change the rate, but that is my own theories, so we’ll get back to yours. With regards to your beans analogy, it does have a direction, one of volume, more beans = more volume. As I said, I believe time is different to all other dimensions. Time existed before the beginning of the universe and will exist after, after all nothing still needs time to take place in. We can travel a length of temperature, if you are at 10 degrees for 2 seconds you travel at ten degrees for two seconds, if you go from 5 degrees to 10 in 2 seconds you have accelerated at 2.5 degrees per second. We travel in time, we travel for a length of seconds, but we can only travel at a fixed rate and we can’t travel for a negative value of seconds. If anything time is the only scalar dimension. All other dimensions are vectors. Time has only one direction all others have 2. If you take time out of all equations nothing could happen because there is no time for it to happen in, if you want to say that time is a human invention and doesn’t exist, then you have to use the same argument to say the other dimensions don’t exist after all every dimension is just a term we use to describe the state of an object therefore you don’t have any equations. Yahoo no science……. Science needs the dimension of time to describe the change of state of an object to try and understand the way things work. It seems the essay you provide and the arguments that have been going back and forth are the very reason the theory of relativity came about in the first place, taking definitions and terms that can mean several things, and taking them from a relative or perceived result to an actual physical result. Think on this, if humans didn’t exist to define time, would the rest of the universe suddenly stop working.