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saac

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About saac

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  1. Louise I remember watching that Horizon video some time ago, really enjoyable and just shows how challenging the concept is. The little companion video with Prof Gowers, for me at least, sums up the dangers of a literal interpretation of infinity. With some very basic algebraic operations Gowers demonstrates how infinity can lead to a nonsensical conclusion that 1 + 1 = 1. ∞= 1/0 ( a commonly accepted definition) 0 x ∞ = 1 (0+0) ∞ = 1 0 x ∞ + 0 x ∞ = 1 (line 2) but 0 x ∞ = 1 therefore 1 + 1 = 1 The outcome is clearly "real world" nonsense; however, as Gowers explains, one cannot treat infinity as a normal number and expect all the usual laws of arithmetic to hold. Infinity, aye there be monsters, but also beauty as Blake found: "To see a World in a grain of sand And Heaven in a wild flower, Hold infinity in the palm of your hand, And eternity in an hour" William Blake fragments from "Auguries of Innocence , To See A World" Jim - still beneath an infinite cloud cover
  2. The hunt for the Higgs Boson captured the world's attention but there is an awful lot going on at CERN outside of the LHC. CERN Current Projects As an aside if you find yourself visiting Geneva that take some time to visit CERN, the public exhibition is well worth the effort. Really convenient too, only a short tram ride from the city centre. Jim
  3. I think it was done in a crystal, as Andrew said they are really making the refractive index do the work. I believe the laser pulse was effectively slowed to a walking pace! But again what does it really mean. In a most recent example that I read scientist were able to alternate a crystal from being transparent to opaque with a laser. They were manipulating the material by changing the way the photons from the laser interacted with the atoms of the crystal. Here is an equally intriguing concept - the femto camera which allows visualisation of short pulses of laser light. Another example of where I have to say ok so what exactly am I looking at here! Femto Camera Jim
  4. Ah Kirk O' Shots my home ground. You're right about the lack of line of sight, used to drive along the M8 watching the Black Hill transmitters appear above the cloud line! Come to think of it the cloud line there was often infinite (give or take a few feet) Jim
  5. Alan what a great write up, I really enjoyed reading that. You put me to shame with your determination, I would really struggle to get up at that time. Just shows what happens if you make the effort. Jim
  6. Agreed. The trouble I have with infinity Andrew is that it is so beguiling that it takes us to strange places where our imagination runs riot. This can be a good thing of course, challenging our assumptions and understanding. It can give rise to new ideas and understanding of the world. But if we are not careful it can take us down rabbit holes. Whenever I see infinity in the equation I here a little voice saying "ok so what does this mean in reality". The equation is telling me something, most likely I have something wrong and normally in my boundary conditions. If infinity is real and physically achievable then perhaps the world won't end in a zombie apocalypse after all. Perhaps CERN will in the near future discover that a non zero rest mass particle can indeed travel at the speed of light (by accident of course) - only at that instance for the universe to disappear from existence as infinity is attained. Infinity was best described to me as a process - we can tend toward infinity but never reach it - once reached it is no longer infinity. Mathematicians will however defend infinity to the death, they love it, it intrigues of course it does. Perhaps more so because they have the luxury of not having to cut metal and turn the equation into reality. I am of course an engineer, as Sheldon Cooper from the Big Bang Theory described, "the younger, slower brother of physics". I do love that line - it's my excuse in class. Jim
  7. That would be my fist thing to look at Dan, if as you say the handset has been proven to work directly with the mount then I think it is pointing to a com conflict rather than an issue with the connector on the handset. Good luck with running this one to ground, faults like this can be frustrating. I manage to overcome the bug issue with Win 10 by swapping the prolific USB driver for an FTDI driver - no issue with EQMOD or com conflict since - touch wood Jim
  8. Dan are you sure the problem lies with the handset connection? Does the handset connect to the mount when you use just the handset itself? When I connect my computer to my AZ EQ6 it does not involve the handset at all. I use a serial/usb cable straight from the computer to the mount and connect via EQMOD. When I have had problems with this it was due to the well known Win 10 prolific driver conflict on the usb/serial cable. Looking at the photograph of your handset socket I don't think the pins are that badly corroded - there is plenty of shiny copper there to make a good connection. Jim
  9. Don't get too excited about the term "infinite", it's nothing more than a mathematical operator that points to a gap in our understanding. Physicist hate it when the maths points to "infinite". Reality is much more complicated and interesting than the dead end of infinity on the other side of the equal sign. Jim
  10. Reverend Georges Lemaitre had a bit of a hard time convincing Einstein that his theory was anything but simplistic. Took Einstein a while but he was eventually swayed by the emerging evidence. Today of course there are a number of other theories some more fanciful than others but the one thing that marks Lemaitre's theory, latterly as modified by the Lambda CDM boundaries, is the ubiquity of the evidence. The model fits what we see remarkably well. That's not to say that the model is not challenging, of course it is. By its very definition it leaves questions unanswered, notably "what was before". In truth the model never made any pretence to answer such questions, we simply don't have anyway of applying our understanding of physics there - there is no physics there! Equally, the "expansion into what" question leaves us unsatisfied. We don't like the answer because it does not fit with our experience in our everyday interaction with the world. But that is the nature of physics, it is not there to reflect our safe understanding of reality. As an aside there was a BBC Horizon programme (presented by Prof Jim Al-Khalili) that compared the current challenges to the Big Bang model, it was very watchable and interesting to see the current direction of research. I must admit, I wasn't swayed by notions of holographic projections, multiple universes etc so I'm still with Lemaitre. I have a saved copy that I use in class but I'll see if I can find the link on the iPlayer if it is still there. Jim
  11. There is no way you would see any Mars/Jupiter impact from the UK with a telescope - it would be cloudy Jim
  12. We have already past the point of complacency with these laser pointers and the idiots that misuse them. One lady in Clydebank has paid a heavy price. I can't help but think that we will see more casualties of the complacency. http://www.bbc.co.uk/news/uk-scotland-glasgow-west-37396748 Jim
  13. I think the main thing to consider is would there be any advantage over a more traditional approach. First consider the initial purchase, then cost of craning in. I'm a bit pressed at the moment to see any major advantage and a real big disadvantage when attempting to relocate or dispose of it. Aesthetics may also be a concern if sited in a residential location (garden etc). Now if it were to be used on a remote unmanned site then security would be one advantage perhaps. Jim
  14. I think you have identified the root of the problem Andrew. The very counter intuitive nature of light in its quantum realm means that many of our questions are invalid from the outset. We end up chasing ourselves down rabbit holes in search for an explanation rather than consider we may need to reconsider the question. Jim
  15. I think we are pushing against the same open door regarding the first part of your reply The photon is not travelling at infinite speed, nor faster than the speed of light. The Universe is safe! I'm not sure why you then go on to say that the light from distant galaxies arrives instantly - if that is what you are saying, my apology If I have misunderstood. We do have to consider relativistic effects - from our reference the light from say Andromeda (2.5 million light years distant) takes 2.5 million years to arrive. Hence we can consider that we are looking at Andromeda as it was 2.5 million years ago. However from the light's perspective it has travelled a much shorter distance and as far as it is concerned it will have a different journey time. The times recorded by us, the observer, and the photon will not be the same as there is no absolute frame of reference for time. So we can consider that we are looking into the past. The Universe is safe again- I think I would contest that there is no doubt, save for any interaction the photon may have had during its journey, about our understanding, I certainly don't consider it to be opinion as the governing physics is pretty much established and tested. Jim