### Bernadette Mercieca

Research -Does anyone have a Maths Community of Practice in their school in a Melbourne area? Keen to research this for my PhD

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Does anyone have a Maths Community of Practice in their school in a Melbourne area? Keen to research this for my PhD

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Did you know that "bipropagation" and "border pairs algorithm" outperform the backpropagation in many ways?

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Well it's not a big deal. You just take the weights and run them through PSO: http://visualstudiomagazine.com/articles/2013/12/01/neural-network-training-using-particle-swarm-optimization.aspx

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Does anyone here have any experience with programming their own symbolic mathematics library and would like to share a few tips? I have been working on one for a while now in C# and have a few questions concerning some simplification algorithms.

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Euler's conjecture refuted !

Euler's conjecture, a theory proposed by Leonhard Euler in 1769, hung in there for 200 years. Then L.J. Lander and T.R. Parkin came along in 1966, and debunked the conjecture in two swift sentences.

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It probably was. In the end it is a paper of math guys. They know how to write precisely :-)

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An extra algorithm, this time on Fast WHT...

http://www.quantatrisk.com/2015/04/10/fast-walsh-hadamard-transform-python-matlab/

http://www.quantatrisk.com/2015/04/10/fast-walsh-hadamard-transform-python-matlab/

Fast Walsh–Hadamard Transform in Python and its comparison to Matlab's version as well to Python's Slow Walsh–Hadamard Transform.

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Hi Buddies,

You must know the series and parallel circuits and know how to calculate the equicalent resistance of it.

But you did not know the formula for general complex resistance network.

I don't know how to attach a pdf file here, so I have to add below link, in which the attached paper, "The Formula for the Equicalent Resistance of Complex Resistance Network.pdf", give you the answer. You will feel the electrifying beauty of the formula.

You're welcome to discuss any question of it.

Thanks,

Deli

You must know the series and parallel circuits and know how to calculate the equicalent resistance of it.

But you did not know the formula for general complex resistance network.

I don't know how to attach a pdf file here, so I have to add below link, in which the attached paper, "The Formula for the Equicalent Resistance of Complex Resistance Network.pdf", give you the answer. You will feel the electrifying beauty of the formula.

You're welcome to discuss any question of it.

Thanks,

Deli

Hi All, I have found the formula for the equicalent resistance of general complex resistance network, and written a printable article. So if you are interested in it, you can downlad the attachment to read. You are welcome to raise any question. Thanks, ...

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Send it to deli.zhang21th@gmail.com, I will check the issue.

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Demonstrates how different models of #informationretrieval (IR) can be combined in the same #framework used to formulate the general #principles of #quantum #mechanics. All the standard results can be applied to address problems in IR, such as pseudo-relevance feedback, relevance feedback and ostensive retrieval. The relation with quantum computing is examined. Appendices with background material on #physics and #mathematics are also included #geometry

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Hello, I'm looking for a website that gives me various math equations based on a topic. I have come across many websites that do so, but it's very time consuming as I face having to go through pages of lessons to find such equations.

Is there a website where if I give it a topic, (ex. Vectors, Parabolas, Trigonometry...) it will only give me equations relating to such topic?

Is there a website where if I give it a topic, (ex. Vectors, Parabolas, Trigonometry...) it will only give me equations relating to such topic?

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I don't want to use Wikipedia because I have to scroll through so much content just to get a single formula.

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I give a purely mathematical analysis strongly suggesting that the orbs I photographed one day cannot at all be explained as mere particles of dust in front of the camera.

Photo date: March 26, 2015. Photographer: Mark Mahin. Orbs are unusual circular anomalies that appear in photos like the photo below. In previous posts I have done experiments debunking the "orb zone theory" -- the claim th...

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Otherwise known as Lens Flare. http://en.wikipedia.org/wiki/Lens_flare

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Fermi physics/math problem solved

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It looks like an artificial problem to me. I don't have time to investigate it right now either. There are issues though before I'm convinced of its veracity.

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Take for example a proof

4x + 2y = 6 for x = 5 and y = 8

Since L.H.S is not equal to R.H.S.

This cannot be proved right.

But......

0*(4x + 2y) = 0 * 6

0 = 0

Now ... L.H.S = R.H.S

Does that mean a proof has two solutions , one that is always true (0 = 0) and the other depends....

4x + 2y = 6 for x = 5 and y = 8

Since L.H.S is not equal to R.H.S.

This cannot be proved right.

But......

0*(4x + 2y) = 0 * 6

0 = 0

Now ... L.H.S = R.H.S

Does that mean a proof has two solutions , one that is always true (0 = 0) and the other depends....

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Vu Dinh

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I uh... have nothing more to say on the topic. I personally prefer to abstain from trying to define the undefined behaviors.

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You guys might enjoy this blog post :)

I have been long due for an update to the development blog of my project. Truth is, I got a little sidetracked with a lot of personal things (I promise I wasn't too lazy!). That being said, I have a...

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We're trying to find a global pattern of notation. **If you were not educated in the United States**, please answer the following questions:

1. What does 3¾ equal?

2. How would you write 7/4 as a combination of an integer and a fraction?

3. What country did you learn math in?

1. What does 3¾ equal?

2. How would you write 7/4 as a combination of an integer and a fraction?

3. What country did you learn math in?

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1) 15/4

2) 1 and 3/4

3)canada

2) 1 and 3/4

3)canada

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Researchers are on the trail of a mysterious connection between number theory, algebra and string theory.

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End of conic sections. Standard solves, interprets and explains.

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I×,A=R×B

R=√(d2/4ε-c

Whether

√(d2/4ε-c=I×,A/B.

True or False.

R=√(d2/4ε-c

Whether

√(d2/4ε-c=I×,A/B.

True or False.

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Original question: "... looking to make a 3-column layout similar to that of piccsy.com. Given a number of images of the same width but varying height, what is a algorithm to order them so that the difference in column lengths is minimal?"

Paddy McCarthy originally shared:

http://stackoverflow.com/questions/5626520/fitting-n-variable-height-images-into-3-similar-length-column-layout/5689594#5689594

Not so much new, but one I'm proud of.

Not so much new, but one I'm proud of.

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Can gravity be derived from quantum mechanics?

I've just watched a video where the speaker seems to be claiming that if you have a predictive quantum theory of matter particles, then you can derive General Relativity, or more generally a metric of space time.

So if I were to be able to derive quantum theory starting from nothing more than a manifold, would this allow me to derive the metric of spacetime

I've just watched a video where the speaker seems to be claiming that if you have a predictive quantum theory of matter particles, then you can derive General Relativity, or more generally a metric of space time.

So if I were to be able to derive quantum theory starting from nothing more than a manifold, would this allow me to derive the metric of spacetime

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+Layra Idarani

Sorry if I offended you. It was not intentional. My point was that as mathematicians we are employing a level of abstraction which has no physical counterpart. That abstraction in our minds is a kind of space in which we put our models. Our mind's eye has access to information about the various entities and can see how they relate to each other. However, physically all information about a disconnected region would reside only in that region. Nothing outside those regions would be able to process anything about them. Sure it is a stretch of the imagination how reality could not process things we can plainly see in our mind's eye. But I think physically we have to consider it. There in no mind outside the disconnected regions to process their relationships.

Anyway, thanks for the help. I appreciate it.

Sorry if I offended you. It was not intentional. My point was that as mathematicians we are employing a level of abstraction which has no physical counterpart. That abstraction in our minds is a kind of space in which we put our models. Our mind's eye has access to information about the various entities and can see how they relate to each other. However, physically all information about a disconnected region would reside only in that region. Nothing outside those regions would be able to process anything about them. Sure it is a stretch of the imagination how reality could not process things we can plainly see in our mind's eye. But I think physically we have to consider it. There in no mind outside the disconnected regions to process their relationships.

Anyway, thanks for the help. I appreciate it.

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Mathematician made famous by Hollywood will share US$765,000 award with Louis Nirenberg for work in the field of geometric analysis.

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This guys awesome

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"In this paper, we develop a cascadic multigrid algorithm for fast computation of the Fiedler vector of a graph Laplacian, namely, the eigenvector corresponding to the second smallest eigenvalue. This vector has been found to have applications in fields such as graph partitioning and graph drawing. The algorithm is a purely algebraic approach based on a heavy edge coarsening scheme and pointwise smoothing for refinement. To gain theoretical insight, we also consider the related cascadic multigrid method in the geometric setting for elliptic eigenvalue problems and show its uniform convergence under certain assumptions. Numerical tests are presented for computing the Fiedler vector of several practical graphs, and numerical results show the efficiency and optimality of our proposed cascadic multigrid algorithm."

"A Cascadic Multigrid Algorithm for Computing the Fiedler Vector of Graph Laplacians" was published in the Journal of Computational Mathematics. It's not Urschel's first paper.

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+David Johnston I agree binary curves are **potentially** vulnerable, but so far the only curves with proven demonstrated vulnerability are binary elliptic curves with small embedding degree. It is simply not the case that all binary curves are proven vulnerable, because not all binary elliptic curves have small embedding degree.

You claimed that "binary extension field Wierstrass [sic] elliptic curves ... are proven insecure" (a direct, verbatim quote from you), which is just wrong.

You claimed that "binary extension field Wierstrass [sic] elliptic curves ... are proven insecure" (a direct, verbatim quote from you), which is just wrong.

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