enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Pushout (category theory) - Wikipedia

    en.wikipedia.org/wiki/Pushout_(category_theory)

    The Seifert–van Kampen theorem answers the following question. Suppose we have a path-connected space X, covered by path-connected open subspaces A and B whose intersection D is also path-connected. (Assume also that the basepoint * lies in the intersection of A and B.)

  3. Hilbert's fifth problem - Wikipedia

    en.wikipedia.org/wiki/Hilbert's_fifth_problem

    The question Hilbert asked was an acute one of making this precise: is there any difference if a restriction to smooth manifolds is imposed? The expected answer was in the negative (the classical groups, the most central examples in Lie group theory, are smooth manifolds). This was eventually confirmed in the early 1950s.

  4. Hilbert's third problem - Wikipedia

    en.wikipedia.org/wiki/Hilbert's_third_problem

    This was confirmed within the year by his student Max Dehn, who proved that the answer in general is "no" by producing a counterexample. [ 2 ] The answer for the analogous question about polygons in 2 dimensions is "yes" and had been known for a long time; this is the Wallace–Bolyai–Gerwien theorem .

  5. Hilbert's tenth problem - Wikipedia

    en.wikipedia.org/wiki/Hilbert's_tenth_problem

    Hilbert's tenth problem is the tenth on the list of mathematical problems that the German mathematician David Hilbert posed in 1900. It is the challenge to provide a general algorithm that, for any given Diophantine equation (a polynomial equation with integer coefficients and a finite number of unknowns), can decide whether the equation has a solution with all unknowns taking integer values.

  6. Stone's theorem on one-parameter unitary groups - Wikipedia

    en.wikipedia.org/wiki/Stone's_theorem_on_one...

    In both parts of the theorem, the expression is defined by means of the functional calculus, which uses the spectral theorem for unbounded self-adjoint operators. The operator A {\displaystyle A} is called the infinitesimal generator of ( U t ) t ∈ R . {\displaystyle (U_{t})_{t\in \mathbb {R} }.}

  7. Classification of finite simple groups - Wikipedia

    en.wikipedia.org/wiki/Classification_of_finite...

    In mathematics, the classification of finite simple groups (popularly called the enormous theorem [1] [2]) is a result of group theory stating that every finite simple group is either cyclic, or alternating, or belongs to a broad infinite class called the groups of Lie type, or else it is one of twenty-six exceptions, called sporadic (the Tits group is sometimes regarded as a sporadic group ...

  8. Entscheidungsproblem - Wikipedia

    en.wikipedia.org/wiki/Entscheidungsproblem

    A negative answer to the Entscheidungsproblem was then given by Alonzo Church in 1935–36 (Church's theorem) and independently shortly thereafter by Alan Turing in 1936 (Turing's proof). Church proved that there is no computable function which decides, for two given λ-calculus expressions, whether they are equivalent or not.

  9. Pythagorean theorem - Wikipedia

    en.wikipedia.org/wiki/Pythagorean_theorem

    In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle.It states that the area of the square whose side is the hypotenuse (the side opposite the right angle) is equal to the sum of the areas of the squares on the other two sides.