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space-time

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http://hyperphysics.phy-astr.gsu.edu/hbase/electric/maxeq.html

I noticed that the notations for those integrals do not match the notations for line integrals of vector fields that I learned on the following page:

http://tutorial.math.lamar.edu/Classes/CalcIII/CurlDivergence.aspx

(Look in the last two blue boxes on the page I just posted)

The integrals in the Maxwell equations on the hyperphysics page have differentials (dA and ds) that have the vector arrow head symbols over them.

In the line integrals on the Calculus III page (http://tutorial.math.lamar.edu/Classes/CalcIII/CurlDivergence.aspx) in the last two blue boxes, you can see that the differentials dA and ds are present either in the line integral itself or in the double integral. However, on this page those differentials do not have arrow heads over them.This makes me question whether the integrals in the Maxwell equations are actually even line integrals or if they are surface integrals. I wonder this because I notice that on this page on surface integrals (http://tutorial.math.lamar.edu/Classes/CalcIII/SurfIntVectorField.aspx) the integrals have the differential ds with an arrow head over it (unlike on the page with the line integrals). That aspect is similar to some of the integrals in the Maxwell equations on the hyperphysics page. However, the ds (w/ arrow head) differential is only present within double integrals on the page about surface integrals (unlike in the hyperphysics page where the ds w/ arrow head differential is present in integrals that look like line integrals that satisfy Green's theorem.) Additionally, I haven't seen any surface integrals that have the circle in the middle of the integral sign like the ones on the hyperphysics page. I have only seen that on line integrals. Finally, no dA (w/ arrowhead) differential appears on the surface integral page. This is why I question what type of integrals the hyperphysics page is using.In short, is the hyperphysics page using line integrals, surface integrals, or some other type of integral? If it is using line integrals, then which type of line integral is each equation using. Are Gauss' two laws the type of vector field line integrals that use the curl, while Faraday's law of induction and Ampere's law are the type that uses the divergence (or vice versa)? If you want to know what I mean by these two types, then here is what I mean:

http://tutorial.math.lamar.edu/Classes/CalcIII/CurlDivergence.aspx (last two blue boxes)