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  1. J

    Moving the description to the right of an icon

    I have this webpage: http://www.generalrelativityandlqg.co.uk/test.html My question is can you tell me how to modify the html code so that the description and "Download.pdf" is to the right of the pdf icon? The easiest way possible. Thanks.
  2. J

    I Mistake in CLQG thesis?

    I've been reading this interesting thesis recently posted. But I think I spotted a mistake. On page 52 of "Semi-Classical Holomorphic Transition Amplitudes in Covariant Loop Quantum Gravity": https://arxiv.org/pdf/2001.04651.pdf It says "In general, removing ##k## vertices from ##[v_0, v_1, ...
  3. J

    Making a copy of a KNOPPIX 5.0 disc that boots

    I had a KNOPPIX 5.0 disc. I made a copy of the files on this disc, but I then damaged the disc. I have tried simply burning these files onto a dvd disc but it wont boot. Can I use the files that I saved to created a "bootable" KNOPPIX disc?
  4. J

    Driver for my printer/scanner

    Looking for a driver for my HP Laser Jet M1120 MFP printer/scanner that works with windows 10. Thanks
  5. J

    Booting from USB to default to KNOPPIX

    I have an external cd drive for my laptop. When I restart my computer I want it to boot from this external drive and my KNOPPIX disc. I'm trying to get my computer to default to the USB upon restarting. But I'm not sure how to do it. When the computer restarts I press F2 for setup (I have...
  6. J

    LaTeX Subscript on the left

    I am working with a "ket" ##|0>_{loc}##, and I want to display the corresponding "bra" where the subscript ##loc## appears on the left side. The best I can do is this \;_{loc} <0| but this isn't satisfactory: ##\;_{loc} <0|##. Is there a specific command for putting the subscript on the left...
  7. J

    I Relating integral expressions for Euler's constant

    Euler's constant is defined as ##\gamma = \lim_{n \rightarrow \infty} \left( 1 + {1 \over 2} + {1 \over 3} + \cdots + {1 \over n} - \ln n \right)##. This can be easily represented as an integral: ## \gamma = \int_0^\infty \left( {1 \over 1 - e^{-x}} - {1 \over x} \right) e^{-x} dx \qquad Eq.1...
  8. J

    B Proofs: Hypotenuse is the longest side of a right triangle

    I want to prove that the hypotenuse is the longest side of a right angled triangle. Could people check that the proof I'm giving is correct? Say the hypotenuse is of length ##c## and the other two sides are of length ##a## and ##b##. First of all, we obviously have: ##a^2 + b^2 > a^2 \quad##...
  9. J

    I Commutator between Casimirs and generators for Lorentz group

    The generators ##\{ L^1, L^2 , L^3 , K^1 , K^2 , K^3 \}## of the Lorentz group satisfy the Lie algebra: \begin{array}{l} [L^i , L^j] = \epsilon^{ij}_{\;\; k} L^k \\ [L^i , K^j] = \epsilon^{ij}_{\;\; k} K^k \\ [K^i , K^j] = \epsilon^{ij}_{\;\; k} L^k \end{array} It has the Casimirs C_1 =...
  10. J

    A LQG wiki page in book

    Go to amazon.co.uk and do a search for: Quantum Gravity & Gravitational Waves: " Ripples in The Curvature of Space-Time " Paperback – 7 Dec 2015 by Edited by Paul F. Kisak (Author) Look inside the book on the chapter on loop quantum gravity. The guy has taken the wikipedia page on LQG and just...
  11. J

    A check: shortest distance from point to line

    We want to know the shortest distance from the point P to the line (see figure 1). As far as I know it is given by the length of the segment perpendicular to the line that joins the line to the point. Can you check this argument I give is correct? Part A. First let us draw in the segment from...
  12. J

    Who and when - simple piece of geometry

    It is well known that: The shortest distance from a point to a line is the length of the line segment which is perpendicular to the line and joins to the point. Who first proved this? How far back in time does it go?
  13. J

    Relation between "widths" of non-paralleogram

    I'm trying to relate different ways of getting a value for the "width" of a non-parallelogram. The non-parallelogram is given in figure 1: note that the left-hand side edge is vertical, the right-hand side is tilted 4 degrees away from vertical, and the bottom edge is 24 degrees below the...
  14. J

    How to explain this?

    I buy a packet of 28 biscuits with intention of eating two biscuits every lunch time (including weekends). However, sometimes I get greedy and eat an extra biscuit at lunch time (I always eat 2 or 3 biscuits each day). If I DONT eat any extra I would end up eating the last two biscuits on say a...
  15. J

    Deduction of the action of this unitary on the wavefunction

    I have operators satisfying ##[\hat{Z} , \hat{E}] = i \hbar##. The operators ##\hat{Z}## and ##\hat{E}## are taken to be Hermitian. You consider the unitary operator ##U_\lambda = \exp (i \lambda \hat{Z} / \hbar)##. I have proved that ##U_\lambda \hat{E} U_\lambda^\dagger = \hat{E} - \lambda...
  16. J

    One of these is wrong.

    I buy a box of 28 doughnuts with the intention of eating two doughnuts each lunch time. If I stick to two doughnuts per day I end up eating the last two doughnuts on say a Thursday. (I then need to start the next box of 28 doughnuts the day after that on the Friday at lunch time.) I have a...
  17. J

    What are the causes of mass delusion?

    What are the causes of mass delusion? Conformity? Pluralistic ignorance? (everybody seems sincere in their convictions it must just be me!) Illusions of unanimity? Illusions of invulnerability? Direct pressure on any member who questions the group to conform - disloyalty! The list goes on... I...
  18. J

    LaTeX Inserting figure into Latex

    I am trying to insert the tif file: https://dl.dropboxusercontent.com/u/81787406/image.tif [Broken] into a Latex file with: \usepackage{graphicx} \begin{figure}[ht!] \centering \includegraphics[width=50mm]{image.tif} \end{figure} but when I latex it I get the error: "Cannot determine size...
  19. J

    Will society ever get rid of stupidity?

    I'm keen on the idea of groupthink. I have read that psychologists find (as do I) that when people think as a group they go stupid... ...here is an recent example I have encountered. Say you buy a box of 7 doughnuts every Friday morning with the intention of eating one doughnut every noon...
  20. J

    Inner product structure for classical diff equations

    I'm interested in what people know about the application of inner product structures (usually reserved for QM) to diff equations describing classical physics, in particular non- hermitician diff operator of the Fokker-Plank equation. Thanks.
  21. J

    How repeat prescriptions work

    Say you are on a 14 day repeat prescription. Two tablets to be taken per day, so 28 tablets. If I picked up and started the first prescription on say a Tuesday would the next prescription be issued on another Tuesday? I work it out this way...I write out a log. The first day is in my log is a...
  22. J

    Einstein or non science?

    There was a recent post about "parroting Einstein". There are these people I know who have got themselves a new idea about rectangles. They think that you can take a 2 by 1 rectangle and make it half the size, not by putting it into the distance but by angling it! This seems like utter...
  23. J

    Number of doughnuts

    I buy a box of 7 doughnuts and intend to eat 1 a day starting on say a Friday. Say I get greedy and eat all 7 doughnuts by the end of Tuesday and then buy another box of doughnuts and eat 1 a day starting from the Wednesday. How many extra doughnuts have I eaten during the 7 day period starting...
  24. J

    Bit of an odd request

    I've indicated two rectangles. Can peeps tell me what they get for the ratio of widths? And then the ratio of lengths? Thanks. rectangles.JPG
  25. J

    On general expansion of cos nΘ

    So I know \cos n \theta + i \sin n \theta = (\cos \theta + i \sin \theta)^n and by applying binomial to the RHS and taking the real part gives you: \cos n \theta = \sum_{k=0}^{\lfloor {n \over 2} \rfloor} C^n_{2k} (\cos^2 \theta - 1)^k \cos^{n - 2k} \theta . I have come across another...
  26. J

    C/++/# Getting back into C++ with knoppix

    Been a long time since I did any C/C++. I have an older version of knoppix which looks like it might have C++. I'll need some step by step help here - dont know very much. I go to the menu, go to "Development", and there is a "KDevelop: C/C++ (IDE for C/C++)". Should I click on this or...
  27. J

    Fuids - vorticity from viscocity

    If invisid flow starts with no vorticity then no vorticity will be produced. This can be understood intuitively: we note that of the three types of force that can act on a cubic fluid element, the pressure, body forces, and viscous forces, only the viscous shear forces are able to give rotary...
  28. J

    Coupled 2nd order diff eq's (Bessel functions?)

    I have derived these pair of coupled diff equations for U_1 (r) and U_2 (r): r^2 \dfrac{d^2 U_1 (r)}{dr^2} + r \dfrac{d U_1 (r)}{dr} + r^2 U_2(r) = 0 and r^2 \dfrac{d^2 U_2 (r)}{dr^2} + r \dfrac{d U_2 (r)}{dr} - r^2 U_1(r) = 0 Or written in matrix form (r^2 \dfrac{d^2}{dr^2} + r...
  29. J

    Medical Froment's sign with cubital tunnel sydrome

    Recently I had a fairly serious case of cubital Tunnel Syndrome with symptoms of hand clawing and Froment's sign. However I have been told Froment's sign never happens with cubital tunnel syndrome. However the book "Anatomic Basis of Neurologic Diagnosis" states that Froment's sign is a cardinal...
  30. J

    Groupthink in ordinary groups

    It was suggested in Smolin's book "The trouble with physics" that stringy people may have succumb to a group condition called groupthink - this is where social factors lead people to defective decision making processes. More generally, no offense to string people as it might be just a mild...
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