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Fine structure constant changes over time

  1. Jul 2, 2004 #1
    In this month's edition of the "New Scientist" magazine (July 2004),
    there is an article which says that the fine structure constant alpha
    was smaller
    in the past ( alpha = e^2/ hbar c), and the speed of light was
    Since the speed of light can be given by the ratio of E/B (electric
    field/ magnetic field) does this mean that the electric and magnetic
    fields of photons could have been different in the past?
    Energy in a photon is distributed between the electric and magnetic
    fields, and if E and B had changed in the past then energy must have
    left the photon with some E and B associated with it - perhaps another
    photon with a smaller wavelength.If a photon from a distant galaxy
    originally had a wavelength of
    10^ - 7 metres (and therefore a frequency of 10^15),since, according
    to the article in the magazine,there is evidence that the constant has
    by about 4 parts in 10^8 over 2 x 10^9 years,this would mean that the
    energy of any photons created from a photon of wavelength 10^ - 7
    metres,coming from a galaxy at a distance of 2 x 10^9 years,would be:

    (10^15 / 10^8 x 4 = 2.5 x 10^6
    so the created photon would have a maximum frequency of 7.5 x 10^6 and
    since the speed of light is about 3 x 10^8 m/s it would have a
    wavelength of about
    3 x 10^8 / 2.5 x 10^6 = 120 metres.

    So, one possible way to test whether or not the fine structure
    constant has changed with time, would be to look for photons in space
    with this wavelength
    and to see if they are as abundant as photons from galaxies with
    wavelengths corresponding to 10^ -7 metres ( 10^-7 metres at the time
    they were emitted from the galaxies).
  2. jcsd
  3. Jul 4, 2004 #2
    Careful how you interpret the article. We don't *know* that these fundamental constants (alpha, c, hbar, G, etc...) were different in the past. It's just a theory which is being used to try and explain strange observations (for example, the accelerated expansion of the universe). This isn't a new idea, either -- even Dirac proposed that constants may not be constant on cosmological time scales.
  4. Jul 11, 2004 #3
    By the way, according to my theoretical researches, the fine structure constant depends on amplitude of fluctuations (i.e. it has geometrical sense) and consequently it cannot be a constant.
    Generally speaking, theories which are constructed on world constants have one common feature – they are nonconstant in time.
  5. Jul 12, 2004 #4


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    Originally posted by kurious,

  6. Jul 12, 2004 #5
    The vacuum is poorly understood - hence some people put the energy density at 10^120 J /m^3 - when experiment suggests 10^-10 J /m^3.
    It is not easyto draw conclusions about what the vacuum is composed of- never mind how light would behave in it at a different epoch of the universe.
  7. Jul 13, 2004 #6
    Hie according to an article (French edition of American Scientific N° 320 June 2004 page28) related to recent observations made by the astronomic Observatory of Strasbourg, universal constants... are constant since ... over 10^9 years. These measurements are in contradiction with (your article and) older one made in 1999 by John Webb in Hawai (Keck telescop). This article suggests that some theory should be revisited according to these new informations (e.g. string theory).
  8. Jul 13, 2004 #7


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    Originally posted by kurious:
    It may not be easy to draw conclusions about the composition of the vacccum, but we can certainly observe how it should behave at different epochs. The vacuum cannot change its composition with time, only its state is able to change - just like how only the states of matter change with temperature but not the composition of the matter so also the vacuum can only change its state.
    This change of state of the vacuum can only be one of relative compression. It is the same as comparing the vacuum that exists between molecules within a glass of liquid hydrogen and that which exists between the molecules in a glass of hydrogen gas. The only difference that affects the velocity of light is the density of the vacuum.
    We know already that e-m radiation travels at a slower velocity in a denser medium and is 'bent' more than in a thinner medium. Einstein's experiment to show how light bends as it grazes the sun early in the last century settled that as far as cosmological scales go and that is in agreement with what we observe in gas, liquid and solid matter.
    The immediate implication here is not that the article is 'wrong', the article only presents empirical information which must be correct.

    However, we know also that as light velocity slows the velocity of matter in the same state of vacuum increases - just like the velocity of orbit closer to the sun increases with decreasing orbital distance but the velocity of light decreases. Therefore if c were different in the past there must have been a change in the angular momentum of the electron on which alpha ( alpha = e^2/ hbar c)is based. This simply means that the fine structure constant should be constant over time - it might be better described as a 'gearing' of the matter-vacuum-time interface rather than as a fundamental constant.
  9. Jul 13, 2004 #8
    Really, if we speak about density of energy and the compressed vacuum, hence, in the past the vacuum occupied smaller volume.
    But it means, that we cannot separate vacuum from space in the own brains.
    Let's discuss the mathematical nature of the fine structure constant.
  10. Jul 22, 2004 #9


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    I have always thought of the 'vacuum' as another word for 'space', or 'space-time'.
    But you know Vlamir, mathematics is only the framework on which we construct our theory, the theory cannot be determined by mathematical expressions. To discuss the mathematical nature of the fine structure constant is like trying to paint a portrait by looking at an individuals shadow.
    In any case, if the velocity of light changes (due to a greater compression of the vacuum) in the mathematical expression, then we must also realise that the greater compression of the vacuum has the opposite effect on matter and therefore the angular momentum expression (Planck constant) changes also.
    This means that the value of alpha will not change although the velocity of light and the Planck constant change.
    What we ought to examine might be the quantity of basic charge that appears in the expression for alpha.
    But what is the mathematical expression for 'charge'. My logic tells me that the function e^2 that appears in the alpha expression has units of kilogram metre. How can we express this mathematically?
  11. Jul 24, 2004 #10
    For many years I studied electrophysiological features of creative thinking.
    In result, I have come to the conclusion, that a brain of an individual (to tell more truly, nervous system of an individual) is not capable to design a true picture of the universe.
    Therefore, I agree with your standpoint, that the vacuum is not neither empty space, nor suspension of space and time.
    But we have no other method for the analysis of results of experiences, except of mathematical comparison.
    I had read some works where the fine structure constant was calculated with the help of various mathematical constants and operations.
    I think, you mean these methods.
    I would like to show you the method, which gives value of the fine structure constant both in experiences of a mechanical resonance, and in optical experiences:

    This method shows also, that the electric charge has no physical sense (since it has incomprehensible unit of measurements), but the square of electric charge e^2 has the concrete physical nature.
    I think, mathematical formulas can prompt – where we are mistaken.
    Last edited: Jul 24, 2004
  12. Jul 28, 2004 #11


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    some excellent points in your post, I will read up on your coupling of constants file soon, but I'm rather busy right now.
    What you have said implies that we can never attain 'grand theory of everything', and in some ways I agree. But I still prefer creative thought to mathematical reasoning.
  13. Jul 29, 2004 #12
    I have a similar situation with a free time. By the evening I get tired, so have no forces to approach computer. Summer short. It is necessary to work from morning to night to have the warm house and a piece of bread in the winter.
    As to 'grand theory of everything', I think, this theory exists, but it is inaccessible for modern homo sapience. Conditions (laws) of a life and development, which were created for itself by people, completely exclude an opportunity of comprehension of this theory.
    Generally speaking, any creative idea is a remembrance.
    Probably, this remembrance has the genetic nature and wakes up in depths of molecular structures of nervous system of the person.
    In my researches of the mechanical resonance I did not put the purpose to receive and explain the fine structure constant. The mathematics has led me to this result.
    Except of the fine structure constant, I have found many other interesting mathematical concurrences, but to explain their nature I cannot.
    It seems to me, as if someone omnipotent sometimes prompts me, what I should make.
    If I begin to do mistakes – he severely punishes me.
  14. Jul 30, 2004 #13
    All of physics assumes matter and energy existing in emptiness. That's "background independent". But look at a TV screen. The picture does not exist in nothing, it exist in a bunch of prearranged pixels.

    If you examine closer, you will notice the TV screen cannot reproduce lines in certain directions. The screen can be said to represent the classic two dimensions of a flat plane, but instead of reproducing lines, it reproduces short steps (strings?) to represent lines in certain directions. Look at the letter V. It is made of short lines in steps, because the TV screen has to exist as small generators of light. A TV screen’s pixels arranged in a pattern only have three directions inherent in it. The flat screen could be said to have three dimensions because the pixels only go in three directions. It portrays the two dimensions of a plane, but not precisely. In all, the TV screen has five dimensions!

    What if space is made of points of matter rather than nothingness? Space as points of matter would have six underlying dimensions, since physical points in a volume of space can only be arranged in six directions.

    A TV screen can be small with small pixels closer together, or large with larger pixels. The speed of a car going across the screen is relative to the screen. But the car is actually going faster on a large screen.

    If space is points of matter rather than nothing, then in younger expanding space the points are closer together. The speed of light would appear the same, but it would actually be slower, just like the car moving across a smaller screen is actually moving slower.

    If expanding space is made of points of matter rather than made of nothing, then space has a total of ten dimensions, and light would actually be moving at a different speed today than before.

    This is not complex. A TV screen has five total dimensions because the pixels are arranged in three directions and though it actually can't reproduce lines in certain directions, it can appear to reproduce lines in the classic two dimensions. (That is a total five dimensions.) Objects actually move faster across a bigger screen, though they move at a constant rate according to the screen size.

    If space is expanding points of matter, then light is traveling the same speed relative to the size of space, but it is actually traveling faster in older space.

    That is the opposite conclusion to "the speed of light was greater in the past", but if space is expanding points of matter, and if light is drawn from point to point by an alpha energy, then in older space the energy between points could be running down, which you also said was the case. So, due to less efficiency in older less dense space, light would appear to be moving slightly slower relative to the perceived size of space.
  15. Jul 30, 2004 #14


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    It really does make more sense that c increases over time. Perhaps that would explain the apparent expansion of the universe. In a denser universe [as in the past], photons would experience more collisions, hence take longer to reach us than they do now. I'm not convinced that is the case, but it makes a lot more sense than c slowing down over time.
  16. Jul 30, 2004 #15
    Fine structure constant, like many terms in QFT, is a misnomer - the "constant" is actually a variable, dependent on the energy. For a detailed explanation read Peskin and Schroeder's expostion of the renormalization group.
    P.S. The renormalization "group" is another misnomer - it is actually a semigroup.
  17. Jul 30, 2004 #16

    It is interesting to note the attention paid to vacuum in this forum. On a webpage discontinued for lack of interest, I made the case for vacuum as the only fundamental force needed to explain the universe. On that page I showed that the fractions of electron charge found by experiment are the same as the fractions of radii found in observed solar orbits, comet rings and in theoretical galaxy arms.
    On my current webpage I show how vacuum theory accounts for the structure of fundamental particles in a novel manner; it also shows how this structure explains electromagnetic charge.
    Of relevance to this forum is that it explains the relationship between force (vacuum) and anti-force (matter) in that the relationship can alter in two ways, either changes in volume or density (transfer in or out of matter).
    Within the universe the transfer process is caused by expansion and the result is the gradual 'changing of all universal constants' . Expansion, of course, arises from the vacuum between universes.
    Last edited by a moderator: Jul 30, 2004
  18. Jul 30, 2004 #17
    It takes a little slight of hand to get to c slowing down, but it is experimentally slowing down, so that's what we have to explain.

    Instead of empty space with a lot of objects in it, think of space MADE of points of matter.

    Like this line made of A's.


    compared to this line made of A's.


    The rule is, light travels from A to A in the same amount of time because, let's say, it is drawn by a force that is between the A's. So it travels faster when the A's are farther apart. And yet, since it has to travel physically faster, it would be harder to increase from the more dense space in the line above to the less dense space in the line below with perfect efficiency. So in a space made of matter, and ruled by physical forces, let's say c determines that it takes one second to get from one A to another A. If the A's are almost three times farther apart in an older part of space, then a photon, while trying to make it in one second, in a physical space made of real matter and real force, it might actually take .999 of a second to go almost three times farther in bigger and older space, while the massless image of car always goes exactly the same speed relative to the size of the TV screen.

    I am looking at a relatively clumsy physical version of space: space made of points of matter, as opposed to a perfectly neat mathematical version of space. That clumsy version has 9 spatial dimensions when neatly arranged. It can physically rearrange itself five different ways to have five different sets of dimensions.

    And I too am sure the vacuum accounts for all force, and that matter accounts for all anti-force. But in a space made of points of matter, the vacuum is between the points. Two points separated into the vacuum are a string, and the vacuum force sucking them back together is the strong force, string tension. It's very simple. Space is made of physical points. This idea can be used to explain a lot of weird stuff we are seeing experimentally.
  19. Jul 31, 2004 #18
    vacuum accounts for all force,----- But in a space made of points of matter, the vacuum is between the points.
    Two points separated into the vacuum are a string, and the vacuum force sucking them back together is the strong force,

    Almost exactly what I have been saying for several years; but why points of matter why not points of vacuum (Zero Points).
    Why confuse the issue with strings the term is not necessary - stick with the Law of Economy, two radials do not make a string.
    Why limit the action to the strong force when the force between two ZPs is determined by the density of the force carrier. therefore the force could be any one of the four forces. That means that all the so-called forces are variations of a vacuum force/anti-vacuum force relationship; gravity is simply vacuum with a weak carrier "sucking objects together "(your words).
    What makes the vacuum weak? In my opinion it is an increase in force carrier, that means more matter equals less vacuum, hence force plus anti-force equals a different constant for each density (force) level
    Last edited by a moderator: Jul 31, 2004
  20. Jul 31, 2004 #19
    Elas, have you tried putting your ideas to physical review D.Michio Kaku said on physics forums that people should do this because they will get a fair hearing from experts who will assess their theory properly.I sent an equation in which predicts quark masses, that I had derived by trial and error,and even though I had no fundamental derivation for the equation they gave it very reasonable consideration
    just in case it might have been right.I suggest you send your hypothesis into them by the internet because,as I say,they can give you an expert opinion.
  21. Jul 31, 2004 #20
    Dear gentlemen,
    The problem consists, that the brain of the person is formed under influence of the limited amount of physical and chemical impacts on "screen" of space - time. These influences create concrete dynamic patterns in nervous cells. In the further life the person uses these patterns automatically (i.e. subconsciously) and creates from them the own picture of a universe.
    Any other patterns are inaccessible for a human brain.
    I know sad experiment on talented children. These children were forced to learn, to so-called, abstract thinking. In result, at them neuropsychic diseases had started.
    Therefore, I think, that we should learn to understand mathematics.
    Hertz had told about the theory by Maxwell: "It is impossible to study this wonderful theory, that occasionally there was not feel, that in the mathematical formulas are generic independent life and own reason, that they are cleverer than we, they are cleverer even of opened them, that they give more, than in them was earlier enclosed."
    As to the fine structure constant, it results from several operations of mathematical approximation, and it is displayed at stimulating of oscillations in a narrow range of energies. For these reasons, I could not to name it as global constant.
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