All articles starting with M

Matrix function

A matrix function extends a scalar function such as the exponential, logarithm, sine, or square root to a square matrix, defined through the matrix's eigenstructure rather than applied to each entry.

Oct 21, 2026

Matrix Gla protein

Matrix Gla protein, or MGP, is a vitamin K-dependent extracellular matrix protein secreted by vascular smooth muscle cells and chondrocytes that binds calcium and inhibits arterial calcification.

Matrix isolation is a sample-preparation technique that dilutes reactive or unstable molecules in an inert matrix, usually solid argon or nitrogen, at cryogenic temperature so their structure can be identified by spectroscopy.

Matrix logarithm

The matrix logarithm of a square matrix A is any matrix X whose matrix exponential is A, so e^X = A. It need not exist or be unique.

Matrix management

Matrix management, also called a matrix organization, is an arrangement where employees report to two managers, one functional and one project-based, formalized in the 1950s US aerospace industry.

Matrix mechanics

Matrix mechanics, also known as Heisenberg matrix mechanics, is the first complete formulation of quantum mechanics, developed in 1925, representing observables like position and momentum by noncommuting Hermitian matrices.

Matrix metallopeptidase 13

Matrix metallopeptidase 13 (MMP-13, collagenase-3, CLG3) is a zinc-dependent human collagenase cloned in 1994 from breast carcinoma; it cleaves type II collagen at least 10 times faster than MMP-1 and is implicated in osteoarthritis, skeletal development, and cancer.

Matrix metalloproteinase

Matrix metalloproteinases (MMPs, matrixins), 23 human zinc-dependent metzincin endopeptidases of MEROPS family M10, degrade extracellular matrix and non-matrix substrates; classified into collagenases, gelatinases, stromelysins, matrilysins, and membrane-type MMPs; regulated by cysteine-switch zymogens and TIMPs; no approved cancer inhibitor.

Matrix multiplication

Matrix multiplication combines two matrices into a third, each entry a dot product of a row with a column; it is not commutative and costs O(n³) operations.

Matrix multiplication algorithm

A matrix multiplication algorithm is a procedure for computing the product of two matrices, classically costing about 2n³ operations; since Strassen's 1969 algorithm the exponent has fallen below 2.372.

Matrix norm

A matrix norm assigns each matrix a nonnegative size under the norm axioms, measuring how much it can amplify a vector and underpinning error analysis and condition numbers.

Matrix number

A matrix number is an identifier a record company assigns to a specific recording, etched into the runout area, with one number per side of a disc.

Matrix Partners India

Matrix Partners India is an India-focused early-stage venture capital firm founded in 2006 as the India arm of US firm Matrix Partners, backing unicorns including Ola and Razorpay.

Matrix pencil

A matrix pencil is the family of matrices A − λB for same-size matrices A and B, central to the generalized eigenvalue problem Ax = λBx.

Matrix pencil method

The matrix pencil method is a numerical technique that estimates the poles and residues of damped complex exponentials from uniformly sampled data, widely used in signal processing and electromagnetics.

Matrix polarimetry

Matrix polarimetry is an optical measurement technique that determines a sample's full polarization response by measuring its 4×4 Mueller matrix, used in microscopy and materials characterization.

Matrix population model

A matrix population model is a demographic method that projects populations divided into age or stage classes through a matrix of survival and reproduction rates, introduced by P. H. Leslie in 1945.

Matrix product state

A matrix product state (MPS) represents a quantum many-body wave function as a one-dimensional chain of small tensors, one per lattice site, and underlies the density-matrix renormalization group.

Oct 21, 2026

Matrix protein 1

Matrix protein 1 (M1), influenza A virus's most abundant structural protein, a 252-amino-acid, ~28 kDa segment 7 product forming the matrix layer under the envelope; drives assembly, budding, vRNP export, and pH-dependent uncoating.

Matrix similarity

Matrix similarity, also called matrix conjugation or similarity transformation, is a relation between square matrices of the same order: A and B are similar when B = S⁻¹AS for some invertible S.

Matrix solid-phase dispersion

Matrix solid-phase dispersion is an extraction technique in analytical chemistry in which a solid or semi-solid sample is blended with an abrasive sorbent and analytes are recovered by solvent elution.

Matrix theory (M-theory)

Matrix theory, also called the BFSS matrix model, is a conjectured nonperturbative definition of M-theory, proposed by Banks, Fischler, Shenker, and Susskind in October 1996.

Oct 20, 2026

MATRIX trial (NCT01433627)

MATRIX (NCT01433627), Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of AngioX, a three-trial European randomized program in acute coronary syndrome: radial vs femoral access, bivalirudin vs heparin, and bivalirudin infusion duration.

Matrix-assisted laser desorption/ionization

Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique in mass spectrometry, introduced in 1987 by Karas and coworkers and most often coupled to time-of-flight analysis of proteins, peptides, and polymers.

Matrix-assisted laser desorption/ionization mass spectrometry imaging

Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a label-free technique that maps molecules, from lipids to proteins, across tissue sections, first demonstrated by Caprioli in 1997 and used in drug and cancer research.