Recent content by russel

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    Graduate Is This Process Markovian and What Is Its Transition Matrix?

    I tried to prove that P(X(n+1) | X(1),...,X(n))=P(X(n+1) | X(n)) but I can't. Must I use the P(A|B)=P(A,B)/P(B) ? Is it easier to prove that has independent increments and, therefore, it's markovian? The funny part is I found the transition matrix... Could I just say that the probability X(n)...
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    Graduate Is This Process Markovian and What Is Its Transition Matrix?

    Hello there, I'm stuck at a problem on markov chains... Could anyone help? Here it is: There are two machines that operate or don't during a day. Let $$X(n)$$ be the number of machines operating during the n-th day. Every machine is independently operating during the n-th day with probability...
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    Graduate Finite axiomatizability of a Theory

    What I had in mind was about computation related subjects, like the one you mention about enumerating all proofs. So, it has to do with the "power" of the theory too? Has it to do with noncompleteness too? For example, if you give a theorem to a not finitely axiomatizable theory it may be not...
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    Graduate Finite axiomatizability of a Theory

    Hello to everyone, I would like to ask what does it mean that a theory is NOT finitely axiomatizable? What are the pleasant and unpleasant consequences of that?
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    Graduate Are any two infinite-dim. V.Spaces isomorphic?

    Hello there, I'd like to ask if the Φ space (the one where each element is a sequence of finite non-zero terms) with norm 1 is isomorphic to Φ space with norm 2. Is it or not? And why? Has this to do with the fact that Φ is never Banach?
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    Graduate Prove that a normed space is not Banach

    The exercise does not refer to a particular space. It is just a normed space X with an uncountable Hamel basis. A solution I came up with was to make a finite dimension closed subspace and show using baire that it is X, leading to a contadiction. If the problem gave us a space for this example...
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    Graduate Prove that a normed space is not Banach

    Hello everyone, I have a problem and cannot solve it. Could you help? Here it is We have a normed space and an uncountable Hamel basis of it. Prove that it is not a Banach space. Should I use Baire theorem? Any suggestions?
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    Graduate Show that a group of operators generates a Lie algebra

    referring to the initial problem, could someone thoroughly explain how to prove that this Lie algebra is a semi-simple one?
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    Graduate Show that a group of operators generates a Lie algebra

    Oh, I see. So, I'll choose every element and see if this condition is satisfied.
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    Graduate Show that a group of operators generates a Lie algebra

    I'll haven't had enough time, so I didn't really managed to solve it. As far as I know, a lie algebra is a semi-simple one if it is a direct sum of simple lie algebras. I will follow this path? Or should I think of a different way to prove it?
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    Graduate Show that a group of operators generates a Lie algebra

    I think I got it! Thanks a lot! What about the last equation? How do I prove it?
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    Graduate Show that a group of operators generates a Lie algebra

    ok! I fixed it! I didn't know the exact code, sorry!
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    Graduate Show that a group of operators generates a Lie algebra

    Hello there! Above is a problem that has to do with Lie Theory. Here it is: The operators P_{i},J,T (i,j=1,2) satisfy the following permutation relations: [J,P_{i}]= \epsilon_{ij}P_{ij},[P_{i},P_{j}]= \epsilon_{ij}T, [J,T]=[P_{i},T]=0 Show that these operators generate a Lie algebra. Is that...