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Thread: speed of light=costant?????

  1. #1 speed of light=costant????? 
    3s
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    I wonder why today every body is hanging on to what is believed to be atoms?
    I learned at school about atoms and molecules.atoms are the smallest particle of matter, which have still all the characteristics of that matter. but if a core releases a photon,it was not the smallest particle,the atom I mean.Then they say its a particle without mass...Like a car without a car.Then they say its the fastest speed possible,light travels at a fixed speed.
    Today there are gyroscopes working with a coiled optic fibre working on the principal of light travelling faster counter earth rotation (they call it Sagnac effect,...)
    electrons,protons,nuons,gluons,nutrino's,... all based on a atom model,nobody has ever seen
    I have seen a picture showing a surface where they moved atoms around (IBM). How can you move atoms, without getting tangled up with the electrons? How did Einstein ever come to the figure of light speed? Does an atom look like a solar system because of lack of imagination?


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  3. #2  
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    It's all theory. THEORY.

    Sure its observable, but try observing all known science in non-minkowski space. It goes all hairy. Light speed isn't constant everywhere in all circumstances. In fact, it can go a fraction faster in a magnetic sub atomic distanced space (I can't remember the name of it now).

    In some water like substance it is moved around a lot faster, creating something called 'Cherenkov radiation' which is a wierd blue haze.

    The speed of light is constant in a vacuum of Minkowski space, the speed being 2.99792458 metres per second/per second.

    As for you saying atoms are like planets. Yes they are, but imagine the planets appearing everywhere around the sun at once (this is called an electron cloud) which isn't observable its just a probablity of where the electrons or planets are.

    Electromagnetism and the other forces are alike each other, EM and Gravity are very similar its just that EM is about 10 to the power 36 times more powerful than gravity. They all interact somehow and that needs to be proven with some GUTs (joke lol, It means Grand Unified theory).


    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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    The speed of light is constant to all observers in all reference frames. That's an observation. Why we observe that was studied by Einstein and others.

    The coiled fiber gyroscope does not assume that light is traveling faster or slower it travels a greater or smaller distance as the coil is rotated.

    Cherenkov radiation is given off by particles, not by light. In this case a particle enters a medium (not a vacuum) at a speed faster than light moves through the medium and emits energy. Again, the speed of light is not the issue here.

    The atoms that were moved around with a special microscope. Check out this link:

    http://www.warrenrobinett.com/nano/index.html

    If the world of the atom and light seems weird then you might be interested in looking around at the early history of quantum mechanics. The early researchers were surprised at the unusual properties of the microscopic world that did not match the macroscopic world.
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  5. #4 The Constant? speed of light 
    Forum Freshman vistotutti's Avatar
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    As I understand Einsteins theory (or maybe I don't) he described the relationship between time, space and the speed of light.
    For mathematical reasons, he chose to make the speed of light the constant, and vary space and time.
    But like any good equation, one could choose to keep any factor constant, and vary the others. in fact from the point of view of a person traveling close to the speed of light, they could be forgiven for saying that the speed of light didn't seem as fast as it used to when they were stationary, as time had slowed down for them.

    Put another way if distance were to grow longer, then is not light going to take longer to cross it?
    or if time slows, does not light crossing the same distance take longer.

    It is all a matter of perspective, hence relative. one mans kilometre long ship looks 10 metres long to another man. one hours seems like a mere second to another observer.
    Surly if you are standing on a spaceship you know to be 1 kilometre long, and light taking x time to travel it's length......

    Wait, I just remembered that the light will change frequency( red or blue shift), and energy will be conserved in this manner...

    Ok. forget that rant. I just realised that I Don't understand Einstein.
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    I would like to answer the initial "problem" involving earths rotation and the speed of light. Imagine two people walking, then running. As one person slows down, the other does not increase his speed. Then, imagine the slower person beginning to walk backward. The speed of the other person is still constant from their frame of reference, but the distance between the two increases dramatically faster. This is not speed.

    In the same way, if particle is "shot" across something opposite to its rotation, it will circle said body sooner (because the "ground" below it is moving in the opposite direction). In a simpler manner, two particles of light going in opposite directions have a greater distance between them then if one was traveling and the other was not, or if one was traveling at a lower speed.
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    They made a movie of that about a watch that made you go so fast everyone else stopped moving (from your perception)
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    I saw that movie. It was lame.
    Om mani padme hum

    "In dishonorable things we are not bound to obey any man." - The Book of the Courtier [1561], pg 99 (144 in pdf)
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    Yeah, it was really bad... but it did talk about what hes asking in it. the "science" was based of it
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  10. #9 Re: The Constant? speed of light 
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    Quote Originally Posted by vistotutti
    Ok. forget that rant. I just realised that I Don't understand Einstein.
    I would just like to give honour and respect to the first post fragment in the Physics forum that I completely understood and wholly agreed with. :wink:
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  11. #10 the mind believes what the eye sees 
    3s
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    In this perspective I was thinking...
    What the little world, the world and the universe have in common is matter.To grasp the concept of matter, not matter should also exist, call it vacuum. lets say for example I am a particle and I am aware being a particle. I became aware because when I moved aside, I created a void as big as me. So lets say I am matter and the void, I created is not-me or not-matter. Or you could say matter is me, a 3D body and not-matter is its 3D surface or the perception of the 3D body. When the 3D body moved outside its surface, it became aware of its body. Most likely, becoming aware of its own existence would have been not so nice a feeling because at the same time nothing came into existence, caused by the void itself created. So in the attempt to reclaim its void, it would only move the void from one side of the body to the other side...
    Why this story?
    If you analyse your perception today, you being a well organised cluster of particles,well...
    your ears are specialised in detecting clusters of particles, moving back and forth, within a range of 20-20 000 Hz .
    your eyes are specialised in detecting moving clusters within a wavelength of 390nm-710nm
    Of both types, you have two (how cruel in a 3D universe...)
    Then you have a nose and a taste, both working in conjunction, to detect particle clusters smaller than you, to be qualified or not, as food.
    Then you have a skin, your surface, capable of detecting moving clusters bigger than you
    clusters to be explored,conquered...
    Then of coarse there is technology...
    In humans eager to explore the universe, I can only bow for the intelligence of a brick.
    It was the effort of the monkey that evolved the monkey into a human.
    It was the effort of the human that evolved a brick into a rocket.
    Einstein had it all wrong:
    E=mC˛ should be really
    C=E˛m from the human point of view, C=m from the brick point of view
    C being the world today in which both humans and bricks exist.
    or
    Ib=C and Ih= 1/C, Ib being the intelligence of the brick, Ih being the intelligence of human,
    C being the speed of light...
    What is so difficult to comprehend the universe?
    For the universe to exist, you need particle exchange between at least two particle clusters
    or communication between an observer and its target.
    For a particle to exist, it needs to move therefore in a 3D world, 3 different movements:
    a circular, a torus and a vortex movement
    All awareness of mass (or particle cluster) comprises particles and their movement
    All awareness of mass only involves their surface to interact
    therefore temperature,pressure,colour,sound,weight,radiation ,volt,current,magnetism,...
    are particles either travelling a surface of a cluster or travelling from one cluster to the other
    So they could be expressed in particle speed, speed pattern and particle quantity, then the
    universe only exist out of speed and particles
    I think I could work that out mathematically, though it would require some effort.
    But then again,who am I working for, a brick?
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  12. #11 Re: The Constant? speed of light 
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    Quote Originally Posted by vistotutti
    As I understand Einsteins theory (or maybe I don't) he described the relationship between time, space and the speed of light.
    For mathematical reasons, he chose to make the speed of light the constant, and vary space and time.
    But like any good equation, one could choose to keep any factor constant, and vary the others. in fact from the point of view of a person traveling close to the speed of light, they could be forgiven for saying that the speed of light didn't seem as fast as it used to when they were stationary, as time had slowed down for them.

    Put another way if distance were to grow longer, then is not light going to take longer to cross it?
    or if time slows, does not light crossing the same distance take longer.

    It is all a matter of perspective, hence relative. one mans kilometre long ship looks 10 metres long to another man. one hours seems like a mere second to another observer.
    Surly if you are standing on a spaceship you know to be 1 kilometre long, and light taking x time to travel it's length......

    Wait, I just remembered that the light will change frequency( red or blue shift), and energy will be conserved in this manner...

    Ok. forget that rant. I just realised that I Don't understand Einstein.
    Well, I can't explain everything, but I'd like to point out that the speed of light isn't a variable that's held constant. It's actually a constant. So, no, no matter how fast you go, light always moves towards/away from you at about 300,000,000 m/s. Not only that, but to anyone watching from a different frame of reference, the light is still moving towards/away from you at about 300,000,000 m/s. It is confusing, but so far, no experiment has been able to disprove it, and not for lack of trying.
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    Just a few things.

    First, the speed of light in a given medium is a constant. That is, light travels at one speed in a vacuum (essentially 3.0x10^8 m/s), while at a slightly different speed in air or water. This is what leads to the refractive index of different materials.

    In formulating relativity, Einstein didn't just arbitrarily make the speed of light constant. It was measured as constant in a series of experiments conducted by Michelson and Morley (Michelson-Morley experiment), which was actually aimed at proving the existence of the universal ether (widely believed at the time). That they actually measured light as traveling at a constant speed regardless of its direction of travel relative to the orbit of the earth suggested that the ether theory was flawed, and ultimately served as the impetus for Einstein's formulation of relativity.
    No, the name isn't because I take drugs. I make them.
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  14. #13 Re: speed of light=costant????? 
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    Quote Originally Posted by 3s
    I wonder why today every body is hanging on to what is believed to be atoms?
    I learned at school about atoms and molecules.atoms are the smallest particle of matter, which have still all the characteristics of that matter. but if a core releases a photon,it was not the smallest particle,the atom I mean.Then they say its a particle without mass...Like a car without a car.Then they say its the fastest speed possible,light travels at a fixed speed.
    Today there are gyroscopes working with a coiled optic fibre working on the principal of light travelling faster counter earth rotation (they call it Sagnac effect,...)
    electrons,protons,nuons,gluons,nutrino's,... all based on a atom model,nobody has ever seen
    I have seen a picture showing a surface where they moved atoms around (IBM). How can you move atoms, without getting tangled up with the electrons? How did Einstein ever come to the figure of light speed? Does an atom look like a solar system because of lack of imagination?
    A few points"

    The atom is NOT the smallest particle. Atoms are composed of electrons, neutrons and protons. Neutrons and protons are composed of quarks.

    The atomic theory of matter is pretty well established. If is is incorrect (rather unlikely) the entire discipline of chemistry will come crashing down.

    What the special theory of relativity deals with is the speed of light IN A VACUUM. Further the only assumption regarding that speed is that it is the same in all inertial reference frames. With that assumption and the additional assumption that the laws of physics are the same in all inertial reference frames one DERIVES the Lorentz transformation and concludes that the speed of light is a limiting speed. That seems to be rather well supported by a mountain of experimental data

    What is perceived as a change in the speed of light in a medium is something of an illusion. Photons travel at c, the speed of light in a vacuum, and only at c, even in a medium But in a medium photons are constantly interacting with electrons, being absorbed and re-emited. It is that process of absorption and re-eimision, which takes some time, that is perceived as a speed of light that is less than c at a macroscopic scale.

    At atom DOES NOT look like a little solar system. That was a very early model that more or less worked when the hydrogen atom was modeled but is really rather misleading. Go take a look at a chemistry book and the pictures of the orbital structure.
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    Every occurrence in nature and detected by humans has been given a name...
    At the moment neutrons were named, the atom model existed already,comprising only electrons and protons, keeping the atom in balance. Then there was a scientist (I forgot his name) who was able to remove mass, without the atom getting out of balance.Therefore he concluded that the core of the atom existed, besides protons, out of neutrons.Quarks, I believe came a lot later (if I remember well,they come in different tastes???)
    Indeed the atomic theory is well established, and so was the flatness of the earth, at a certain period in history.It did not make the earth crashing down,finding out otherwise...

    I believe the assumption was first made, the speed of light to be constant and then Einstein and Poincarre defended that space time model (lorentz transformation) because they didn't had a fixed reference frame, because everything is moving in space.Do you need a fixed reference frame to define nature???
    Absorbing and re emitting light...
    I suppose transparent substance means re-emitting light in the same direction ,as it came
    not-transparent, for instance green substance means reflecting the green part of the light...

    The orbital structure of the atom came in existence as a mathematical model, showing the regions where the possibility was the biggest for one to find an electron (orbit is a somewhat circular motion, thus a little solar system....)

    What I think is funny is that Einstein wanted to be sure his law would be applicable throughout the universe and hence came up with the lorentz transformation where as his laws find today their applicability at level of quantum physics, where the laws of nature do not apply????
    Background radiation is believed to be the proof of the bigbang theory, whereas theory has provided a foreground "fog" around the atom (orbital structure)
    Mathematics derived from nature, it shouldn't overrule nature.
    If Pointcarre had lived at the time of Newton, maybe Newton would have stated:
    If an apple three relieves an apple, the earth jumps to catch it...
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  16. #15  
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    I can't tell what that last post is arguing for or against. Would you care to make it a bit more intelligible, or at least clarify your points?
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  17. #16  
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    The reason for starting the topic was to create a cavity in which there is room a GUT (see first reply) could be created. With all science existing, there is no such cavity to be found within this universe. For the GUT to be applicable throughout the universe, it needs to be created within. As for my life quest in trying to understand things, I came across Einstein...
    Einstein who left the whole scientific world, shaking on its foundations...
    E=mC˛ For all the times I tried to understand it, I have posed questions and analysed the answers. I have come to one main conclusion:nobody understands Einstein theory fully.
    No matter what units you're working with, there is a one to one relationship with it's metric equivalent:
    The only thing existing in the reel world is mass and its energy state:
    mass is expressed as newton
    entropy is expressed as joule
    All the other units define a relationship between mass and mass,mass and a device or between a unit and another unit (clock,thermometer,mathematics,...):
    distance is expressed as meter
    time is expressed as second
    speed is expressed as meter/second
    power is expressed as joule/second (watt)
    energy is expressed as watt x second (joule)
    or:
    joule= newton x meter = watt x second
    or:
    watt= joule/second= newton x meter/second
    Some answers I got stated that light speed is C, some stated light speed is C˛ ???

    first case:
    joule=newton x meter/second
    This contradicts with the unit of energy (joule):
    joule=newton x meter

    second case:
    joule=newton x meter˛/second˛
    meter/second˛ is the unit of accelaration
    joule=newton x meter x acceration
    so again some contradiction

    I can comprehend light having a certain speed, so has sound
    I can comprehend red shift (doppler effect)
    I can not understand the world if the unit of length (meter) is a rubber unit
    I can not understand the world if the speed of light to be the maximum speed
    However the world accepted the speed of a photon (meter/second) to be the standard of length (about 300 000 000 meter)

    If science would have proven that the unit of time (second)is a rubber unit I wouldn't have a problem at all to comprehend.
    Time is "only" of by a few seconds a year and "only" of by a day every four year....

    Do you need a nuke to prove the speed of light is a big figure???

    to quote some big achiever, although less known as Einstein (Wittgenstein):
    What exist can be expressed in a simple way.
    to quote Einstein:
    Everybody likes me, nobody understands me...

    Few questions remains: Is there scientific data about the ratio between the mass of electrons,neutrons and protons. Is there any rotation speed known or scientific accepted
    data for electrons,neutrons and protons?

    The only cavity a GUT could be created would be on sub atomic level, get the mathematics watertight and then calculate the one to one relationship between all scientific units.
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  18. #17  
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    I haven't read the whole thing in detail, but I just wanted to make one small comment: the need for leap years has nothing to do with time dilation.
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    mass is expressed as newton
    You poor deluded soul. Mass is expressed in kilograms, not newtons. Newton is the unit of force equal to mass x acceleration, or kg*m/s^2. Hence E=mc^2 is correct and all your so-called contradictions fall apart.

    If science would have proven that the unit of time (second)is a rubber unit I wouldn't have a problem at all to comprehend.
    By your definition of a something being rubber time and space (length) are both rubber. It's called time dilation and length contraction and results from the Lorentz Transformation.
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  20. #19 Re: The Constant? speed of light 
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    Quote Originally Posted by vistotutti
    For mathematical reasons, he chose to make the speed of light the constant, and vary space and time.

    Put another way if distance were to grow longer, then is not light going to take longer to cross it?
    or if time slows, does not light crossing the same distance take longer.

    It is all a matter of perspective, hence relative. one mans kilometre long ship looks 10 metres long to another man. one hours seems like a mere second to another observer.

    Wait, I just remembered that the light will change frequency( red or blue shift), and energy will be conserved in this manner...
    your first affirmation is incorrect, because the speed of light was observed through experiments, its not just a proportion constant.
    your second affirmation is correct, and that is called the dilation of time. since light travels at limited speed, it consumes time to do so, and the longer the distance, the longer time it takes for light to travel through it. however, time doesnt "slow", but it reflects the proportion between speed of light and distance.
    light does change frequency, but frequency isnt speed. frequency has to do with cicles around a inertial centre, and speed has to do with distance traveled in tangent space. and light is just a portion of the electromagnetic spectre, and invisible radiation also travels at speed of light.

    on the other hand, that affirmation about the ships is completely mistaken. again we have to look closely to the situation and its implications. the phenomena of contraction of distances has to do with the measuring of objects that are in movement in relation to an inertial measuring referential. the dilation of time has to do with the necessary amount of time for a person to witness the movement of light across a definite distance. the longer the distance, the longer time it will take for an observer to witness a beam of light crossing a definite space. this is aplicable to all reality phenomena since we can only see what is iluminated by light.
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