Why is the gaussian free field a distribution but Brownian motion is a function?












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As I understand it, a GFF is a generalisation of Brownian motion to dimensions greater than one. However, they seem like very different objects. Brownian motion is just a continuous function (even though it is nowhere differentiable). By contrast, the Gaussian free field is not a function but only a distribution (it does not have well defined values at points, but only under integrals).



What makes these two objects 'the same'? and why does moving from dimension one to two lead to such different behaviour?










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    As I understand it, a GFF is a generalisation of Brownian motion to dimensions greater than one. However, they seem like very different objects. Brownian motion is just a continuous function (even though it is nowhere differentiable). By contrast, the Gaussian free field is not a function but only a distribution (it does not have well defined values at points, but only under integrals).



    What makes these two objects 'the same'? and why does moving from dimension one to two lead to such different behaviour?










    share|cite|improve this question

























      2












      2








      2


      2





      As I understand it, a GFF is a generalisation of Brownian motion to dimensions greater than one. However, they seem like very different objects. Brownian motion is just a continuous function (even though it is nowhere differentiable). By contrast, the Gaussian free field is not a function but only a distribution (it does not have well defined values at points, but only under integrals).



      What makes these two objects 'the same'? and why does moving from dimension one to two lead to such different behaviour?










      share|cite|improve this question













      As I understand it, a GFF is a generalisation of Brownian motion to dimensions greater than one. However, they seem like very different objects. Brownian motion is just a continuous function (even though it is nowhere differentiable). By contrast, the Gaussian free field is not a function but only a distribution (it does not have well defined values at points, but only under integrals).



      What makes these two objects 'the same'? and why does moving from dimension one to two lead to such different behaviour?







      probability-theory stochastic-processes stochastic-calculus stochastic-pde






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      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Nov 18 at 23:12









      prdnr

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