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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  • To complicate things further, there's also Brownian sheet.
    – Zachary Selk
    Nov 19 at 6:22















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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






















  • To complicate things further, there's also Brownian sheet.
    – Zachary Selk
    Nov 19 at 6:22













up vote
2
down vote

favorite
1









up vote
2
down vote

favorite
1






1





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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asked Nov 18 at 23:12









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  • To complicate things further, there's also Brownian sheet.
    – Zachary Selk
    Nov 19 at 6:22


















  • To complicate things further, there's also Brownian sheet.
    – Zachary Selk
    Nov 19 at 6:22
















To complicate things further, there's also Brownian sheet.
– Zachary Selk
Nov 19 at 6:22




To complicate things further, there's also Brownian sheet.
– Zachary Selk
Nov 19 at 6:22















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