How effective is the Mozart effect? In 1993 Rauscher et al. made the surprising claim that, after listening to Mozart's sonata for two pianos (K448) for 10 minutes, normal subjects showed significantly better spatial reasoning skills than after periods of listening to relaxation instructions designed to lower blood pressure or silence. Is the Mozart effect widely accepted? only showed an increase in "spatial intelligence", the results were popularly interpreted as an increase in general IQ. This misconception, and the fact that the music used in the study was by Mozart, had an obvious appeal to those who valued this music;...

When was rollerblading removed from X Games? 2005 Aggressive inline skating was removed from the ESPN X-Games in 2005 although it is still included in the Asian X Games, LG Action Sports Competitions, Montpellier Fise, and many other large competitions, some associated with WRS, some not. Why did everyone stop Rollerblading? The primary reasons were the lack of facilities to support the sport. There were fewer professionals at the time who provided formal training to beginners. Also, the rollerblades were not a cheap commodity to buy. The event of 9/11 made a silent blow to the sport raising terror in...

Is a symmetric matrix always invertible? The short answer is no. Recall that a symmetric matrix is such that it is equal to its own transpose. If we consider the zero (square) matrix of any dimension for a moment, then we can clearly see it's equal to its own transpose. Yet, it is, as seen from the fact that its determinant is zero, not invertible. Is a basis matrix always invertible? So every change-of-basis matrix is necessarily invertible. How do you check if a matrix is invertible? We say that a square matrix is invertible if and only if the...