Is it true that a matrix is always positive semi-definite if it is positive definite?
91409
Semi positive definite matrix is always positive definite matrix
75104
Existence of some type matrix
98631
Postive-semidefiniteness of matrix with entries $1/(a_i+a_j)$
117293
sufficient and necessary conditions for matrix to be diagonalize or triangular
82962
Partial Ordering of Positive Definite Matrices
87318
Why are symmetric positive definite (SPD) matrices so important?
24459
Why does correlation matrix need to be positive semi-definite and what does it mean to be or not to be positive semi-definite?
99600
Show that a 2x2 matrix A is symmetric positive definite if and only if A is symmetric, trace(A) > 0 and det(A) > 0
27306
Positive semi-definite vs positive definite
88820
Three linked question on non-negative definite matrices.
64741
The square root of positive definite matrix
67820
Showing that $(A_{ij})=\left(\frac1{1+x_i+x_j}\right)$ is positive semidefinite
146405
Norm with symmetric positive definite matrix
133496
is $\sqrt{x}$ always positive?
85550
Positive definiteness of difference of inverse matrices
29454
A and B are real, symmetric and positive semi-definite matrices of the same order; is AB diagonalizable?
146316
what is no. of positive eigen value of symmetric matrix A with some given relationship