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Editor's note: In Thursday's programme Melvyn Bragg and his guests discussed Relativity. As always the programme is available to listen to online or to download and keep.



Well, I got through it. People who know more about physics than I do (most of you) will have realised again and again how thin the ice was on which I was attempting to skate. Nevertheless, once again, those who contributed to the programme were not only a safety net and a cradle, but considerate enough to let me say a few words along the way. Martin Rees said afterwards how difficult it was to do this sort of programme without illustrations. "That's why we kept waving our arms around," he said. He also spoke about the number of letters he gets from people who are very interested in physics who sometimes begin "Even Newton was wrong..." Roger Penrose's letters include those that begin by saying how much they admire his books, but then attempt to explain why he's wrong. As a young man apparently Einstein was very dapper and beautifully dressed in the annus mirabilis of 1905, when he produced four papers while not working inside a university or a scientific community – four papers which changed the understanding of the universe. As an older man, the scruffy and bemused-looking mop top (the model for the first Dr Who?). He could have been a refugee from the Marx Brothers. Both Roger Penrose and the producer, Tom Morris, had personal anecdotes transmitted to them down their respective families that although Einstein loved to play the violin, especially in string quartets, and his name commanded only the best people to play with him, he had one grave fault. He couldn't count.

Ruth Gregory said that four dimensions were nothing like as complicated as we thought they were. When we came across a crowd of people and worked out how to navigate our way through them, we were using four dimensions. Martin said that the reason why Einstein's greater theory lay dormant for about forty years at the beginning of the twentieth century was that there were only very crude ways of testing their veracity. They could only come within 10% of establishing the truth. Now they can come within 1/100,000.

Doing this from the train, on the way to Carlisle, to give a talk about my novel in the town in which I was born. The event is being laid on by Gwenda Matthews, an independent bookseller, valiantly and, I hope, successfully continuing in her increasingly lovely occupation. I think it's 400 independent bookshops that have closed down over the last two or three years.

Tunnel, tunnel, tunnel... back in the light again. When I was at a grammar school I used to go into Carlisle sometimes to traipse around the independent bookshops. There was one second-hand bookshop, dug into the castle wall, which was wonderfully ripe for looting, with an extremely benevolent bookseller practically giving them away. Anyway, good luck to Gwenda Matthews and all who share her determination to stay independent.

It's been a John Ball week - filming a BBC documentary on this extraordinary fourteenth century preacher who helped inspire and amplify what has too long been miscalled the Peasants' Revolt. We've been whirling around Kent and Essex; at a wonderful sheep market in Colchester which has been there since at least the twelfth century, to abbey ruins which again – the abbey, that is – date from the twelfth century. Into Chelmsford for an unusual lunch break (i.e. not a sandwich in a car park), beside a river, and young Chelmsford folk wandering in the sunshine while cricket was being played nearby. In and out of churches beside the Essex Marshes, England past and present delighted by the appearance of the sun and leaping out to lap it up.

Best wishes

Melvyn Bragg


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  • Comment number 68. Posted by ProllyMathic

    on 19 Jun 2013 13:27


    Your comments of this nature "Starlight aberration (J Bradley 1727) can be explained as due to the effects of a relative velocity of starlight with respect to Earth's orbital movement. A confirmation of relative light velocity." are precisely the kind of non sequiturs that I have been objecting to throughout this thread. Astronomical effects are not controlled experiments; they don't serve to confirm anything.

    Also you don't seem to have decided whether or not you believe in an absolute reference frame. If you do, then your approach is inconsistent with SR.

    Another point is that if you're moving away from a light source at 100mph, the reason it's got a longer wavelength than when you're moving away at 50 mph is precisely because the speed of light reaches you, in the first case, at a *lower speed relative to your own motion* - hence less energy, per unit time, in the light as it reaches you. What we process as wavelength and frequency are not directly the properties of some actual, longitudinal wave propagating through an ether; they're just a way of speaking of energetic relations.

    Please also see my comments (eg. in my first post) as regards the twin paradox; and I repeat that physics doesn't deal in illusions. The world of the illusory is enough of a limbo realm as it is; relativists seem - in so far as it is possible to comprehend what they have in mind - to be arguing for a second limbo world characterised by being somewhere between the real and the illusory. Physics??

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  • Comment number 67. Posted by Jaffas

    on 19 Jun 2013 09:06

    For mantuesday (52 & 62) and anyone interested to a new approach to relativity.

    A useful definition, in my view, is this:
    "A relativistic effect is just the way something appears to be, while the underlying characteristic itself does not change".
    The part "appears to be" was emphasised in the broadcast but did, at times, become elevated to the status of reality which was not helpful.
    Special Relativity (SR), which is basically a mathematical method for resolving problems of relative movement of an em source and an observer, has come to be regarded as the only one to be used for all situations. There is another choice when the situation is different.

    SR is the only option when movement of source and observer cannot be established related to a common reference point. Where such a common reference can be identified (it is possible!) there are simpler solutions, SR is not then needed and may even be misleading.
    It is not difficult to show that a relative velocity of em radiation, e.g. light, is possible and logical. It can be shown that light travels direct from source to observer in relation to their common reference, Earth for example, unaffected by movement of that reference, e.g. Earth's orbital travel. Precise laser alignment would otherwise not be possible.
    Starlight aberration (J Bradley 1727) can be explained as due to the effects of a relative velocity of starlight with respect to Earth's orbital movement. A confirmation of relative light velocity.

    Source movement changes wavelength, with radiation always at constant C (W de Sitter 1913). Observer movement changes the frequency of the radiation with respect to the observer.
    Applying math to these basic laws of physics yields a relative velocity of light with respect to the observer. From this simple beginning (Basic Relativity - BR say) all relativistic situations can be explained, with the exception of those where only relative movement can be identified between source and observer. Simple resolution of simultaneity, twin paradox, and other 'puzzles' can be demystified by use of BR.

    It is also possible to show that the oft-quoted Michelson-Morley experiment should have yielded interference, well within the sensitivity of the apparatus, at some point(s) during its rotation if length-contraction was a reality. As interference has never been detected in the M-M experiment, this is another relative light velocity confirmation.

    I could continue but am aware that many minds are closed to all but SR - if yours is not, or your healthy curiosity is aroused, there is fully referenced data and math at As well as the usual relativity topics there are studies of absolute rotation (Sagac theory), Pioneer10 anomalous acceleration, Galaxy expansion rate limitations/dark matter magnitude.

    Simplest is often best, the principle of Occam's Razor - see In other words one should apply Basic Relativity (relative light velocity) unless it is necessary to use Special Relativity because a common reference for source and observer cannot be determined.

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  • Comment number 66. Posted by ProllyMathic

    on 18 Jun 2013 12:51

    On the subject of questioning the tenets of science, here's Rupert Sheldrake doing a presentation of his book, The Science Delusion ('Science Set Free' in the US): .

    Note, especially, what he says about 'the most embarrassing episode in the history of our science [metrology]' regarding the fundamental constants, starting half-way through.

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  • Comment number 65. Posted by feedbackdestroyer

    on 17 Jun 2013 12:44

    Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
    Albert Einstein

    Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe.
    Frank Zappa

    We know that quantum mechanics and relativity do not fit together - which is wrong?

    We know that the mass of the universe and relativity do not fit together - which is wrong?

    At either end of the scale there is a major fundamental problem and relativity is in the middle.

    I don't claim to have the answer - that appears to be the job of religion. I only have questions. We don't have to wait for an new paradigm to arise before we question an existing one - on the contrary, it's exactly the other way around. Darwin accepted that his theory could collapse without any other to replace it.

    Science appears to be only interested in money. Careers, funding and politics come first. Who would dare to admit that he doesn't understand relativity (nobody I've seen here so far!) It's a clear case of the "Emperor's New Clothes". Yet Feynman boldly stated "If you think you understand quantum mechanics, you don't!" Well isn't it just fine that even a Nobel winning physicist doesn't understand QM and we are spending billions trying to invent new theories that nobody understands to fit QM to GR which nobody understands to start with. Right.

    Time to bring this nonsense to an end.

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  • Comment number 64. Posted by ProllyMathic

    on 16 Jun 2013 23:51

    Oh and I forgot to say that there is a recent fad in academe to describe people who disagree with Einstein - or indeed others from Jewish families, be they Rothschilds or whoever (but note that the common factor is that they are influential) -- as antisemitic. I have witnessed this ludicrous and decidedly pathetic form of counterattack even among distinguished Professors (note the capital 'P') at respectable universities in the UK.

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  • Comment number 63. Posted by ProllyMathic

    on 16 Jun 2013 18:54

    Mantuesday, billions of dollars get wasted in ever more elaborate efforts to confirm the reality of relativistic effects (as though they can't decide on what it means to confirm a theory, once and for all!) and genuine, honest physicists get their careers and/or reputations ruined by being labelled cranks. Your comments make you just another member of this zombie cult, which will receive anything (discovery of the Higgs boson - yes, must be true, etc.), from the science priesthood. When I was an undergraduate, people actually *questioned* things that were fed to them, and indeed questioned anything that had an aurora of 'mainstream' about it -- whether academic or cultural. Personally, I couldn't trust any news story reporting any kind of sensational discovery (eg. another possible 'missing link' fossil, between the humans and the apes) that came from the scientific community, or, as I have already said, anything hyped; it's all a game of money and manipulation by belief-system. They're taking the Mick.

    The link to the Guy Burniston Brown article, which I feel everyone interested in physics should read:

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  • Comment number 62. Posted by mantuesday

    on 16 Jun 2013 16:32

    feedbackdestroyer, the history of scientific progress is not about people showing 'potential problems' with existing models. Progress comes about when a radically new model overthrows an old one. What is notable about current attempts to discredit Einstein is that none of his critics has an alternative model that stands up to five minutes' scrutiny. Plasma cosmology is laughably inept, ether theory is speculative and unsupported by experimental evidence. And was rejected a century ago for good reasons. GR gives a good description of the universe which can be reconciled with what we observe, dark matter and all. Can you provide an alternative? If you want to dismiss the vast majority of cosmologists on a hunch, that's your prerogative, but don't claim your opinion is self-evidently correct if the truth is that it's wilful and eccentric.

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  • Comment number 61. Posted by feedbackdestroyer

    on 16 Jun 2013 13:04

    mantuesday - even if only one single scientist was to show that Einstein's Relativity was potentially flawed how would that make it "not much of an argument"? Surely that's exactly how science works! Darwin exclaimed that his theory would never be proven but that one single piece of evidence could completely disprove it.

    Was GR not disproven as a comprehensive model when it failed to agree with the observable behaviour of the motion of the galaxies - requiring a twenty times multiplication of the mass of the galaxy for it to fit? Why are you looking for a fictitious "Dark matter/Energy" when the obvious is staring you in the face? You would not accept any other theory that was so fantastically off the mark - except this one that has a gigantic level of cultural, media and educational brainwashing behind it.

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  • Comment number 60. Posted by ProllyMathic

    on 15 Jun 2013 23:05

    I was trying to quote the introduction to Hatch's article but this site cuts out quotation, when done in a certain way. I'll try again.
    Ron R. Hatch:
    "Much can be learned from relativistic clock behavior. The Global Positioning System (GPS) has become a primary source for knowledge of relativistic clock behavior. One of the characteristics of clock behavior clearly evident in GPS is that all clocks in the earth-centered inertial (ECI) frame which are at sea level run at the same rate. A clock at sea level on the equator should run slow according to the Special Relativity Theory (SRT) due to its speed in the ECI frame. However, a clock at sea level on the equator should run faster according to the General Relativity Theory (GRT) due to the spin-induced equatorial bulge which causes the clock to be higher in the earth’s gravitational potential (i.e. at a less negative potential). These two effects, explained by disjoint theories, are of exactly equal magnitude but opposite sign and precisely cancel each other.

    "A somewhat similar effect is observed regarding the clocks on board the GPS satellites. When the satellite is near perigee, it has a faster speed; and the SRT indicates that the clocks should run slower than nominal. But near perigee the satellites have a lower (i.e. more negative) potential in the earth’s gravitational field which, according to GRT, should also result in a slower clock rate. Again, surprisingly, these effects explained by different theories have precisely the same magnitude—but in this case the sign is the same and the two effects add together.
    Why should the magnitude of the clock effects be exactly equal in the two examples above? It is a highly unlikely coincidence. Yet Einstein’s two theories, SRT and GRT, have no explanation for the equality. Since clock effects are a function of velocity squared (kinetic energy) and gravitational potential energy, it would seem that the common factor is related to the energy of the particle. But SRT treats kinetic energy as relative and GRT treats gravitation as a geometric effect completely independent of energy considerations. This suggests a need to search for an underlying mechanism for relativistic phenomena via some other theory. There are a number of other reasons leading to the same conclusion. The alternative which seems to agree best with most of the experimental data is an absolute ether theory."

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  • Comment number 59. Posted by ProllyMathic

    on 15 Jun 2013 23:00

    Mantuesday, you don't seem to have properly read anything I have said. I do not deny that the equations, which are sloppily termed the equations of GR, developed by Grossmann (and which Einstein admitted he did not understand), give results that correspond closely to reality. However, they bear very little semblance to relativity theory. It seems Grossmann knew something about the effects of energy on atomic resonance frequency (and how he knew it is, I concede, rather puzzling), and grafted his knowledge onto Einstein's flawed work, using the 4-vector tensor maths as a thin guise for computations that are in essence about gravitational field energy.

    Energy, however, doesn't feature in relativity, save tangentially in GR. The principle of the conservation of energy is at odds with SR, because it suggests an absolute reference frame in relation to which the kinetic energies of each moving body are realised. In any case, whatever is found by experiment, there is no disputing flawed logic; relativity is replete with logical errors and unlike Roger Penrose I cannot believe that one can patch up an inconsistent theory by adding bits on to it (which is how SR became developed into GR). If you can't see the logical errors, after they have been explained to you, then further discussion is futile.

    Anyhow, for what it's worth, this is what Ron Hatch - the 'one [GPS] expert', as you so demeaningly put it, that I personally cite (though there are others) -- says [note SRT = special theory of relativity, etc.]:

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