Disagree entirely Undefined.......
but anyway......
http://mathworld.wolfram.com/MinkowskiSpace.html
Minkowski space is a four-dimensional space possessing a Minkowski metric
dtau^2=-(dx^0)^2+(dx^1)^2+(dx^2)^2+(dx^3)^2.
Alternatively (but less desirably), it can be considered to have a Euclidean metric but with imaginary time coordinate x^0=ict, where c is the speed of light, by convention c=1 is normally used, and i is the imaginary number sqrt(-1). Minkowski space unifies Euclidean three-space plus time (the "fourth dimension") in Einstein's theory of special relativity.
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http://ncatlab.org/nlab/show/Minkowski+space
Definition
For d−1∈N, d-dimensional Minkowski space is the Lorentzian manifold whose underlying smooth manifold is the Cartesian space Rd and whose pseudo-Riemannian metric is at each point the Minkowski metric.
This is naturally a spacetime.
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ENERGY-DEPENDENT MINKOWSKI METRIC
IN SPACE-TIME
http://www.mathem.pub.ro/proc/bsgp-10/0MIRON01.PDF
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