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Nat Edgar - Antimatter
Curious - no one mentioned the "Standard Model" of particle physics; about 80% of the program concerned the model.From Melvyn's Newsletter:"Is it (the antimatter theory) a new version of how many angels can dance on the point of a needle?"Not much experimental evidence for the "angels dancing" theory ! Whereas ...
Antimatter
The formula E=mc squared was well known before Einstein. A great deal of the hard work of the derivation was carried out during the late 19th Century by the great J.J. Thomson. (Newton also advanced that matter and light were in some sense interchangeable.) Other pre-Einsteinian figures in the derivation and conjecture of the physical validity of the formula included S. Tolver Preston, Oliver Heaviside, Hasenöhrl, P.N. Lebedev and, in particular, Poincare (who supplied, without Einstein's recognition, *all* the basic ideas of special relativity, in his 1904 work) and Olinto De Pretto, who, in 1903, published the formula in a paper in the journal Atti. There were also developments by eg. Planck and G.N. Lewis which were made a very short time after Einstein's 1905 paper but before Einstein's work was at all well known; in contrast to the work of Einstein, these developments were made on solid conceptual foundations. Einstein was shown by Ives (1952) to have assumed what he wanted to prove, so in mathematical terms his derivation would be deemed unacceptable. Further, he just seems to have inserted the 'derivation' rather negligently. How he can have considered that it conforms with the other ideas in special relativity is most obscure. If a body increases in mass with increased velocity, its increased gravity makes for a physical criterion that can serve as a measure of its velocity in non-relative terms. The history of physics is a world of myths.
Chris Whitehead
Would it be possible to visit the work and thought of the philoshopher and spitiual scientist Rudolph Steiner ?A man whose thought covered a vast range and has continued to influence many fields to this day.Thank you.
Lulu Hancock - Antimatter
Here's a thought.My all-to-solid flesh (particularly my bum) is made of matter.Somewhere in the multiverse, there is an equal and opposite anti-matter me.If we met, there would be a colossal annihilation. But because there is a fundamental asymmetry - and matter always comes off slightly better than anti-matter - I would not disappear, but become an ultra-slim version of me. Is this true/possible/completely nuts?If this is true, can anyone fix up a meeting with Anti-Me?
PET in 'Physics and the Human Body' by H Baddeley
Positron emitting radioisotopes produced in a cyclotron eg. F-18 can be attached to deoxyglucose(18FDG.Then a PET scanner can locate sites of active metabolism in the body for functional brain imaging or cancer detection.
Matter and Anti-Matter
The question about why matter and anti-matter don´t immediately cancel each other - is this not the question of how time, space, self and world are gestated into being? In Zen the experience of this is to go beyond time, space self and world and experience the "big bang" happening now moment by moment. It may be that theory will not provide the answer but that we will need to return to the experience of consciousness itself being brought into existence through meditative practice. Deirdre
Antimatter moderating
Thank you, Mr. Bragg, for playing the part of an educated Everyman. Your questions were dead on for a difficult and dense topic.
Roger Foyle, Anti-matter
Dear Melvyn,As a Physics gratuate (just scraped a 3rd class honours!) I found your programme on Anti-matter fascinating.One of the opening comments, that when energy is converted to an equal amount of matter and anti-matter according to m = m.c^2, underlines the "Big Bang Theory" at the creation of the Universe and, for me as a Christian, re-enforces the truth of God as the Creator, and shows how he did it.By the way, I think you look better on the radio than you do in the photograph on the In Our Time web-page.I particularly love your sideswipes at John Humphries and the "Today" team at 8.45 when you promote your programme. It's worth it just to listen to that --quite apart from the prog!Keep up the good work, Melvyn. I listen with 1000 ears.Roger Foyle
léo burton: a universe without origin
in the preamble to this extraordinary programme, it was said that research into anti-matter would contribute to our understanding of the origin of the universe.within the limitations of our culture and language, is it possible for us to think/imagine a universe (or anything that matters) without an origin?can mathematics construct a theoreticial system which has no origin ?
CERN, pet scans, antimatter and cancer
My brother-in-law works in CERN, where they developed the techniques now used in pet scans. How ironic then that when my husband was diagnosed with stage III non-hodgkins lymphoma, it was the technology developed by his brother that helped to diagnose him accurately, to assist in his treatment, and to continue to monitor his recovery.Whilst the discussions had a lot of theoretical content today, I for one will always be grateful that they have a practical application!
David Doff - Antimatter
A few years ago I went to a fete at Dirac's old primary school in Bristol. There is a plaque on the wall of the Dirac equation which I pointed out to several people - none of whom had ever heard of Dirac. On another wall was a plaque commemorating Cary Grant. Everybody knew who he was. A sad reflection on public knowledge of science today.
Roy Vickers - Antimatter
Is it possible that when the "Big Bang" occured and time began, there was an infinitesimally small separation between the creation of matter and antimatter? Tme in effect beginning for matter and antimatter at very slightly different points.This "time separation" being enough of a barrier to keep matter away from antimatter thus preventing annihilation and because ourselves are made from matter and exist in our time we can only see our side of the barrier?
Judith Johnstone - Antimatter
This was a brilliantly illuminating session. Actually managed to make brief notes I could understand on a topic which has been previously incomprehensible. Fantastic!
Tom Milner-Gulland. Antimatter
From a metaphysical perspective anti-matter can be viewed as the capacity, inhering in all substance, of aspects of reality undergo fundamental change: for the components of matter to be, of themselves, annihilated and replaced by other manifestations of matter and energy. It strikes me as rather reductionistic to conceive of discrete particles of anti-matter, even if there appear to be determinate traces of such entities in the form of effects upon the media that are said to detect them. It should be remembered that these traces are *mere* effects; what is more they are invariably *positive* in the sense that they are empirical manifestations. To suggest that there is a positive form of ontology (i.e. being/reality/existence) and negative form of ontology, the two having the capacity to perfectly annihilate one another, will end in nonsense. It says a great deal about modern thinking that there continues to be a kind of blind faith in a) reductionism as advanced by particle physicists and b) such theories as big bang theory - on which I shan't offer an opinion, save to say that it's worth reading Tom van Flandern's 'Top 30 Problems with the Big Bang'; it's online.
Avid listener. In Our Time. Antimatter
A riveting programme. However, one small thing niggles me and it's something I think which crops up often on scientific programmes. I detected it in yours today. Scientists have a theory but it needs more evidence. They go looking and find some. But how much are they influenced by auto-suggestion? Can your contributors say that, in finding the evidence for the imbalance between matter and antimatter in the universe they're not just a little, tiny bit prejudiced in wanting to find some? But really, the programme was excellent and please do not take this as a criticism in any way.
John Grint - Antimatter
This is my favourite story about Paul Dirac, showing the power of his analytical mind in an unlikely setting. During his student days at Cambridge, he was once invited to tea with his tutor. The tutor's wife was knitting by the fireside. Dirac was fascinated; he had never seen knitting before. After observing her carefully for a few minutes he remained in deep thought for a while, then calmly announced, with precise accuracy, that there were just two distinct ways to knit wool into a connected structure.He was right, of course - we call these "Plain" and "Pearl" stitches.
Maxine Etheridge what holds matter together?
Dear Melvyn Bragg,I wonder whether anyone has ever researched the possibility that colour could be the glue that holds matter together.We can recognise everything by its colour from infancy and the only variation seems to be what is around the matter, ie atmosphere. Blood is only red and skin is only altered by the elements it comes into contact with. I want to be convinced I'm wrong by someone because it seems too simple a theory and yet..............fromMaxine Etheridge
Antimatter; Graham Wadsworth
The program did not really answer the question of where all the antimatter has gone. All the contributors accepted that matter and antimatter were created in equal amounts, but then failed to explain clearly why we are now left with an excess of matter. In actual fact, this was dealt with in Stephen Hawking’s book, A Brief History of Time. He states that if all quarks and antiquarks had annihilated each other, then we should be left with a universe filled with radiation but hardly any matter. However, he goes on to explain this by stating that Grand Unified Theories allow quarks to change into antielectrons at high energy. They also allow for the reverse. Then why much more quarks than antiquarks? The answer is that the laws of physics are not quite the same for particles and antiparticles. Up to 1956, it was believed that the laws of physics obeyed each of three separate symmetries called C, P and T. However, the early universe did not obey symmetry T. As a result, more antielectrons turned into quarks than electrons into antiquarks. As the universe expanded and cooled the antiquarks would annihilate with quarks, but since there was a small excess of quarks, this small excess would remain. This then makes up the matter which we see today and of which we ourselves are made.
Tony Cheney Cosmology
Frank Close, Ruth Gregory et al talk about re-creating the conditions of the "big bang" in the LHC, but they are not really doing that, they are "only" reaching the energies involved, but they are leaving out the effect of the massive gravitational fields existing then - after all, the whole mass of the universe was compressed into the early volume - and we know from Einstein that massive gravitational fields have an effect on space and time. Surely this will have time dilation effects on particle formation that don't seem to be taken into account.
Anti-matter: Robert Gore
Well done Melvin, you got in THE killer question and boggled the experts in their tracks. If matter and anti-matter were produced in equal amounts and annihilate immediately why didn't everything disappear right at the beginning? The explanation of tiny asymmetries and flaws in the Laws of Nature seemed to add up to little more than, 'dunno mate'. Strip away the fancy terms, and we are left with a number of profound mysteries. Where did the anti-matter go? Why is the annihilation field between the twin universes of matter and anti-matter not visible, if there, and just exactly what is dark matter and dark energy?We need much more public discussion about all of these topics, because we are in a mediaeval phase in which at the heart of science there is trust and faith and hope and speculation and beauteous mathematical embroidery, but not enough facts. The wonders of science, which are undeniable in terms of incredible products and effects and domestic understandings, like all the other religions, are predicated dreams.We have used science to destroy religion, and have created a society without rules and without a secure founded ethical basis, but now science is turning into a religious belief system itself.Interesting sequel after last week's program in which Socrates was famous for bothering people in the Market Place with seemingly innocent questions that uncovered deep inconsistencies and confusions!
Mike Wells - antimatter & the origin of the univer
Very interesting - BUT!! No mention of gravity, how it may have been acting or affecting in the "beginning" - its a weak force but at intra atomic distances may be considerable - does gravity of antimatter differ from that of matter? I feel that this should have been considered by the commentators & that Melvin may have missed an opportunity to really provoke some more interesting discussion.
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