skipper

skipper

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Member since
Jun 4, 2009
Last active
Oct 16, 2010
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  1. #Threads

    9fbea41d-90fa-411f-8a49-52d8e5481a86

    1) You can adjust the audio level with the volume control. As stated earlier this gives a qualitative measurement of the field...

  2. #Threads

    e15ed761-3775-41c0-a7e1-578fc12b7bc7

    Well, I was kind of hoping someone would raise an objection to using a radio receiver like this. Determining the total background...

  3. #Threads

    125020e4-1259-427e-b383-573918280e46

    radio volume will be the internal control of amplifier right? how does it being maintained constant at various frequencies/power, convey the strength...

  4. #Threads

    e41c6c53-b96f-4c14-bbf7-a590c0938130

    Can you think of a way to use a multimeter as a signal meter that measures field strength? If you attach an...

  5. #Threads

    0dc8f9ce-ea2f-4c21-93fe-90a1c338c2b7

    Mass is conserved. An electron has, like all massive particles, a rest mass. But electrons can only truly be at rest at...

  6. #Threads

    a39f9b68-ccc9-439f-8605-b793084de1b9

    durgais it measuring the received power or frequency?By "it" I assume you mean the radio? The power depends on the strength of...

  7. #Threads

    Measuring an electric field

    Riddle me this: If you have a battery-powered radio, can you think of a way to use it to get a qualitative...

  8. #Threads

    5ca3b380-d895-4adf-9599-098955dbf00b

    I assume you mean a waveform generator? A piece of equipment that has sine, sawtooth, square, etc waveforms at various amplitudes and...

  9. #Threads

    Hypercubic computers

    You may have heard of the Connection Machine. This was/is a massively parallel system in which the processors communicate with each other...

  10. #Threads

    53f9f599-395b-4c0d-b4d6-24436f853a2a

    Compressing files is about redundant codes. What counts as redundant depends on the file. Check out what MPEG and JPEG compression is...

  11. #Threads

    35f53ce8-6870-4615-9ddb-5043e3063fb1

    Okey dokey. I think I've managed to finally see the connection between the puzzles (starting with the Pocket Cube) and Riemann space...

  12. #Threads

    efa23417-76c1-4ad2-912a-2888dce35350

    One other detail I think is important: the figure I keep mentioning which you can form with an algorithm: "X,Y',Z',X", as long...

  13. #Threads

    a13dfa52-5736-4c80-8ab2-59cea36326f4

    Suppose there is a word, or 'work' W, in several parts (here, any sort of construction that be considered "computational" is possible,...

  14. #Threads

    ffd2f241-dfc0-4536-bb0d-65ea2b6569e4

    Hmm. I would say that the movie used a "toy model" of quantum physics.... Put it this way, if you see a...

  15. #Threads

    ceebfe81-fc38-4830-a58a-ee0d352b4638

    Ok, another clue for mathematicians. If you imagine the numbers are piles or stacks of Rubik's cubes, each looks different, but some...

  16. #Threads

    066ffff6-7037-4ba9-a40b-d2b289898020

    Let's look at the first few members of each sequence. 1 9 54 321 1,847 1 6 27 120 534 If I...

  17. #Threads

    77fec134-7903-4435-a78b-3d9c44733b9f

    Have you tried wikipedia, or google? A metric is just another term for a standard measurement or "distance generator". A space with...

  18. #Threads

    33ef9a5b-9716-44a2-a818-c91ec3bdc21b

    A Fibonacci series (recurrence) is: a[sub]n[/sub] = a[sub]n-1[/sub] + a[sub]n-2[/sub], with a[sub]1[/sub]= a[sub]2[/sub] = 1. So a[sub]3[/sub]= 1 + 1, a[sub]4[...

  19. #Threads

    0c2955d6-1f17-413e-bc9d-17b980478d07

    Oops, the second sequence isn't complete, I missed some terms at the end: 1 6 27 120 534 2,256 8,969 33,058 114,149...

  20. #Threads

    c4321bcf-2ff2-4319-bb79-6812b2db3a0f

    Ok both series are what "falls out" of the Pocket Cube. The second is formed by using only quarter turns (QTM), and...

  21. #Threads

    c2e8f97b-92ef-464f-82ae-eba5c1c11674

    This is another sequence that adds to the same total. 1 6 27 120 534 2,256 8,969 33,058 114,149 360,508 930,588 1,350,652...

  22. #Threads

    Recurrence algorithms, logarithmic series etc

    Is there anyone here good at finding recurrence formulas in algorithm design? Or with a good grasp of a logarithmic series like:...

  23. #Threads

    2a7fe060-bef9-4e50-ad15-6b40c32f99e8

    Ok, apologies for the long absence. I have news from the front - the war is going well. No, wait, that was...

  24. #Threads

    17d2f048-6275-4c54-9a72-55f5e3522bb1

    With the T in hysteresis it's usually heat or electromagnetic energy, so abstracting this means going all the way to computational space...

  25. #Threads

    ab5c15cb-a4c4-4281-b4c4-38458a782da4

    You see, tensor calculus lets you do stuff like imagine what a tank of water, or its pressure gradient is like at...

  26. #Threads

    a0695da4-4034-43ec-9c63-a00730fa19bd

    Well, in Newton's time they were still searching for the "essence" of metals - the Philosopher's Stone - and using the forerunner...

  27. #Threads

    Crazy Cubology

    Our generator, who art in the group, give us this day our daily cube. And forgive our trespasses into the Moebius domain,...

  28. #Threads

    77b4d576-24bd-4f7f-8e9f-dd536cceb8d7

    Ok, check this out. If T = -T so the "-" vanishes, when you "rewrite" -T as T and the arrow changes...

  29. #Threads

    b2c1ee15-6355-4749-a364-36f2bfcd812a

    Hmm. A gravitational force exists because of a field. The earth's field is distorted by the moon's. Far away from the earth-moon...

  30. #Threads

    Gravity account

    What does gravity mean to an engineer? They have to make sure all materials will withstand "the force" of gravity that pulls...

  31. #Threads

    b4a2df22-b51c-40e3-a626-480dd7a1218e

    Factorial 0 is 1. Then there is some argument about 0[sup]0[/sup]. Zero is a quotient group in the integers as Z/nZ, n...

  32. #Threads

    Languages, theories, and a theory of languages

    Language is the medium of theory; although we "react" unconsciously to a lot of "theoretical" information, most of it is discarded (from...

  33. #Threads

    Hysteresis model

    Who can guess what this resembles? Is there a "word" in a general (or special) group, which is normal to an hysteresis...

  34. #Threads

    e25e9ada-bf83-4149-b4fc-6dce194e6cbb

    There are a lot of memonics "buried" in these things; apart from building patterns and finding words that preserve them there is...

  35. #Threads

    85166d0d-09dd-4961-936b-0472cc7bc793

    Ah, you see, any letter in the basic alphabet is a number in 4 places, as mentioned. In fact, each "X" an...

  36. #Threads

    c528b636-d97b-4061-a563-b0146ad29643

    Now suppose I want to think about "heat and temperature". There is an obvious "work function" which is rotation of any face,...

  37. #Threads

    30baebf5-28a0-4f8a-a76f-5b92b777bbfa

    Hmm. The title "Turing numbers and geometry" implies a connection between the two subjects. This connection is to the numbers in the...

  38. #Threads

    eb39a4d0-c14d-454c-b1ac-0e71f8cc5acc

    I'm trying to parameterize the space (of stacks of cubes). Obviously the N[sup]3[/sup] geometric parameter, when N = 2 is the number...

  39. #Threads

    cf192ab2-65cd-4f1f-96c2-68f8f607ef38

    There might be a problem or two with the above formulations; the reason 8!3[sup]7[/sup] is divided by 24 is that the 2-cube...

  40. #Threads

    dbdbfdc0-4eac-4bd8-a3a6-6cf97bf22a14

    What is a Turing number? Well, Alan Turing picked up a sheet of paper one day and had a think about what...

  41. #Threads

    Turing numbers and geometry

    Here's some more stuff on the group of cube puzzles: Stacking cubes together is where Erno Rubik started with his eventual design...

  42. #Threads

    f1a9abee-4504-407d-901c-f6833ab45863

    My synth's keyboard is really clunky. I've thought about using some kind of filler in the big gap above the keys (in...

  43. #Threads

    Pressure in liquids

    There were some queries a while back about liquids and the Venturi effect; why pressure is lower when a fluid is compressed...

  44. #Threads

    96c9d0cd-afcd-4250-ad2f-f5be0dd7051c

    Questions: 1) Why was the particular set of puzzles - corresponding to sliced and sectioned Platonic solids, the cube, the dodecahedron, the...

  45. #Threads

    77b57e6c-1146-4390-8b68-2bafd081f89c

    Symmetry: The mechanism of each individual face is a rotor r, which is 'sign-extended' because a conjugation (i.e. a number of places)...

  46. #Threads

    5c041808-e88d-4c41-86df-ced41b03c542

    Here is where I would like to directly connect the algorithmic side of the puzzles in play, to digital computers that use...

  47. #Threads

    1324bb14-b47d-49c5-a13d-2b3039ec781b

    I could keep this up for a while; but I can recommend that interested parties use google and try terms like "rubik's...

  48. #Threads

    eb64a8ef-4e80-4787-8603-ff420d179ec1

    Can you explain what the "*" operator does? Usually this is used to signify conjugation, or multiplication.

  49. #Threads

    fe782a1b-f7e7-4cef-8eaa-7219cd2ee055

    Correction: there are 4 places for the digits, r[sup]1[/sup]r[sup]2[/sup]r[sup]3[/sup]r[sup]4[/sup]. But the last digit = r[sup]0[/sup] = 1, the multiplicative...

  50. #Threads

    ca19d67f-7a8c-4ffb-a990-5dc3ea16cfa2

    Now I have several sequences in hand for the cube groups. The questions in Rubik's permutation puzzles are along the lines: "how...

  51. #Threads

    ed91607e-92dd-47ca-a4e0-294062c5e4ee

    Uh hm. So, if you get your hands on a couple of cube puzzles you can do the "twist" move that builds...

  52. #Threads

    2e3a546d-36ea-4ae2-8601-3d2df67f91ba

    I once agonized over which path to take in the CS domain. But here's the thing: if you have good programming skills...

  53. #Threads

    39334a06-67fc-431a-bd3c-ad3ec5cabfc9

    Another thing I could mention: the generators I've listed are a way to solve a scrambled cube. The "trivial step" in reconstructing...

  54. #Threads

    3e0f07a4-599d-4a25-9a89-6a5a3249411c

    Well, it would take a long time to enumerate all the 4.3 quintillion possible permutations of the 3x3x3 Rubik's cube; however calculating...

  55. #Threads

    8feb349b-387a-4bb9-ae78-b1324446798a

    I should add to this that I did a postgrad in parallel computation, in which an assignment was to design and implement...

  56. #Threads

    75daaa77-e127-4d34-bfba-61870562be07

    Well, thanks to Cube Explorer I now know the length of the "word" that corresponds to my stack-generator: R'FDR' which I label...

  57. #Threads

    9f2b3128-27f1-444c-9a7b-6c27b5352c18

    From wikipedia's <a href="https://en.wikipedia.org/wiki/Clos_network" target="_blank" rel="nofollow noopener noreferrer">Clos Network</a> on Clos switching nets...

  58. #Threads

    e6d6b5eb-db39-4e84-9e8a-bab9f2042e74

    I should be more specific with the term "handle"; I mean by this that a given switching network can switch an input...

  59. #Threads

    d36fd796-df1f-4deb-acbf-8723d99e5a15

    Switching theory: The Rubik's cubes are all made so you can rotate any face, clockwise or anticlockwise. This is equivalent to inverting...

  60. #Threads

    3221f8c4-3a3d-4a12-af70-c1c75dc3ce5f

    Some group theory: The set that generates the first step - of which R'FDR' is a member is a g which is...

  61. #Threads

    Exact sequence question

    This is actually something you can puzzle out on a Rubik's cube, starting with the 2x2x2, although a 3x3x3 is better because...

  62. #Threads

    01d8cd8d-1ccd-4e88-824e-da245842dab1

    Can I ask what led you to guess it was length of English words, just a hunch? Actually when you think about...

  63. #Threads

    a8806c8e-fb73-408c-b587-fbaf0fe9c20f

    Have you looked at GAP or Matlab programs for Golay codes?

  64. #Threads

    57e918d1-a381-42d6-883f-75e41e9415e1

    uh huh. How do you have any idea that you can try English words, and the numbers are the numbers of letters?...

  65. #Threads

    dac37125-91af-4edf-8b1d-3f0b44a2f479

    1,13,2 1,5,3,2 1,4,4,7,3 1,5,3,5,?,? Write it in binary: 1,1101,10 1,101,11,10 1,100,100,111,11 1,101,11,101,?? Rewrite as sums of powers of 2: 0,3+2+0,1 0,2+...

  66. #Threads

    8b5340dc-8535-41a1-9c56-babef717aeb9

    This is 1st year calculus. To calculate a solid of revolution first define the "y" curve that will be revolved around the...