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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
For X a smooth quasi-projective variety and 𝑋[𝑛] its associated Hilbert scheme of n points, we study two canonical Fourier–Mukai transforms 𝖣(𝑋)→𝖣(𝑋[𝑛]), the one along the structure sheaf and the one along the ideal ...
(Doctoral thesis / Doktoravhandling, 2022)
Renewable energy sources receive increasingly more attention as the world seeks cheap, reliable and less CO2-intensive ways of producing electricity. Wind is recognized as an important source of renewable energy and reaches ...
(Doctoral thesis / Doktoravhandling, 2022)
Real algebraic geometry is the study of geometric objects defined by polynomial equations with real coefficients. This domain has connections with many areas of mathematics, such as analytic geometry, algebraic topology ...
(Doctoral thesis / Doktoravhandling, 2022)
A tensor is a multi-dimensional data array, occurring ubiquitously in mathematics, physics, engineering and, more generally, in all the situations where one needs to organize data by more than two indices. If tensors remain ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We argue that there is a link between implicit computational complexity theory and reversible computation. We introduce inherently reversible programming languages which capture the complexity classes etime and Image 1. ...
(Doctoral thesis / Doktoravhandling, 2022)
In this thesis we consider two different kinds of brain malfunctions. The Chiari 1 malformation is characterised by abnormal cerebrospinal fluid (CSF) flow conditions surrounding the brain. The other malfunction we consider ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Gravitational settling of a droplet in air onto a soft substrate is a ubiquitous event relevant to many natural processes and engineering applications. We study this phenomenon by developing a three-phase lubrication model ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
For an infinity of number rings we express stable motivic invariants in terms of topological data determined by the complex numbers, the real numbers and finite fields. We use this to extend Morel’s identification of the ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewedPeer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
This study suggests a stochastic model for time series of daily zonal (circumpolar) mean stratospheric temperature at a given pressure level. It can be seen as an extension of previous studies which have developed stochastic ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Capillaries are the smallest vessels in the body which are responsible for delivering oxygen and nutrients to surrounding cells. Various life-threatening diseases are known to alter the density of healthy capillaries and ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Abstract
Copulas are appealing tools in multivariate probability theory and statistics. Nevertheless, the transfer of this concept to infinite dimensions entails some nontrivial topological and functional analytic ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We present a novel numerical technique for computational models of thin tubular networks embedded in a bulk domain, for example a porous medium. These systems occur in the simulation of fluid flow in vascularized biological ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
This article generalises the concept of realised covariation to Hilbert-space-valued stochastic processes. More precisely, based on high-frequency functional data, we construct an estimator of the trace-class operator-valued ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We present a numerical scheme for the solution of nonlinear mixed-dimensional PDEs describing coupled processes in embedded tubular network system in exchange with a bulk domain. Such problems arise in various biological ...
(Doctoral thesis / Doktoravhandling, 2022)
One of the biggest open problems in Complex Geometry is whether every open Riemann Surface admits a proper holomorphic embedding into the 2-dimensional euclidean complex space, as this provides a good representation of ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We apply the specialization technique based on the decomposition of the diagonal to the intersection of a quadric and cubic hypersurface in P6. We find an explicit example defined over Q that is smooth, and does not admit ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Reliable probabilistic information of the long-term ocean wave climate is important in many coastal and ocean engineering applications such as the design of marine and coastal structures. There is therefore a need to ...
(Doctoral thesis / Doktoravhandling, 2022)
To a mathematician, a surface is a shape that, upon close enough inspection, looks like a flat piece of paper around each of its points. Thus, to an ant, the surface of a bagel is conceived as flat, while the (roughly) ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2022)
We propose Fit4CAD, a benchmark for the evaluation and comparison of methods for fitting simple geometric primitives in point clouds representing CAD objects. This benchmark is meant to help both method developers and those ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
In this paper we propose a boosting algorithm to extend the applicability of a first hitting time model to high-dimensional frameworks. Based on an underlying stochastic process, first hitting time models do not require ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
There is a wide consensus within the polar science, meteorology, and oceanography communities that more in situ observations of the ocean, atmosphere, and sea ice are required to further improve operational forecasting ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2022)
We extend the recently developed rough path theory for Volterra equations from [12] to the case of more rough noise and/or more singular Volterra kernels. It was already observed in [12] that the Volterra rough path ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We prove convergence rates of monotone schemes for conservation laws for Hölder continuous initial data with unbounded total variation, provided that the Hölder exponent of the initial data is greater than 12/. For strictly ...
(Doctoral thesis / Doktoravhandling, 2022)
The last decades have witnessed an exponential growth in the amounts of data that are collected, stored, and shared worldwide daily.
In many scientific disciplines, information consists of a set of sample points describing ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Abstract Assisted reproductive technology (ART) may affect fetal development through epigenetic mechanisms as the timing of ART procedures coincides with the extensive epigenetic remodeling occurring between fertilization ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
This paper deals with the specification of probability distributions expressing ignorance concerning annual or otherwise discretized failure or mortality rates, when these rates can safely be assumed to be increasing and ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Administrative data may suffer from delays or mistakes in reporting. To adjust for the resulting measurement errors, it is often necessary to combine data from related sources, such as sample survey, administrative or ‘big’ ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Objective
To investigate the association between smoking and infertility.
Design
Prospective study.
Setting
Nationwide cohort.
Patients
28,606 women and 27,096 men with questionnaire and genotype information ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
This paper provides sufficient density conditions for the existence of smooth vectors generating a frame or Riesz sequence in the lattice orbit of a square-integrable projective representation of a nilpotent Lie group. The ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We consider converses to the density theorem for square-integrable, irreducible, projective, unitary group representations restricted to lattices using the dimension theory of Hilbert modules over twisted group von Neumann ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2022)
When major disruptions occur in a rail network, the infrastructure manager and train operating companies may be forced to stop trains until the normal status is recovered. A crucial aspect is to identify, for each train, ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
We study distribution dependent stochastic differential equation driven by a continuous process, without any specification on its law, following the approach initiated in [17]. We provide several criteria for existence and ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
In the book Helland (2021) the general problem of reconstructing the Hilbert space formulation in quantum theory is discussed from the point of view of what I called conceptual variables, any variables defined by a person ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
The well known Bell experiment with two actors Alice and Bob is considered. First the simple deduction leading to the CHSH inequality under local realism is reviewed, and some arguments from the literature are recapitulated. ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
In the language {0,1,∘,⪯}, where 0 and 1 are constant symbols, ∘ is a binary function symbol and ⪯ is a binary relation symbol, we formulate two theories, WD and D, that are mutually interpretable with the theory of ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Many banks and credit institutions are required to assess the value of dwellings in their mortgage portfolio. This valuation often relies on an Automated Valuation Model (AVM). Moreover, these institutions often report the ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
This note provides new criteria on a unimodular group G and a discrete series representation (π,Hπ) of formal degree dπ>0 under which any lattice Γ≤G with vol(G/Γ)dπ≤1 (resp. vol(G/Γ)dπ≥1) admits g∈Hπ such that π(Γ)g is a ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2022)
In this note we introduce higher order polar loci as natural generalizations of the classical polar loci, replacing the role of tangent spaces by that of higher order osculating spaces. The close connection between polar ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Abstract Understanding the droplet cloud and spray dynamics is important for the study of the ocean surface and marine boundary layer. The role that the wave energy and the type of wave breaking play in the resulting ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
(Doctoral thesis / Doktoravhandling, 2022)
Traffic volumes are increasing in most of the major modes of transportation. As population centers grow in size and density, the increasing demand for public transit and delivery services leads to increased rail and road ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Longevity and safety of lithium-ion batteries are facilitated by efficient monitoring and adjustment of the battery operating conditions. Hence, it is crucial to implement fast and accurate algorithms for State of Health ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
The bottleneck matrix M of a rooted tree T is a combinatorial object encoding the spatial distribution of the vertices with respect to the root. The spectral radius of M, known as the Perron value of the rooted tree, is ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Abstract We prove the crepant resolution conjecture for Donaldson–Thomas invariants of hard Lefschetz 3-Calabi–Yau (CY3) orbifolds, formulated by Bryan–Cadman–Young, interpreting the statement as an equality of rational ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Objectives This study examined the association between night shift work and risk of breast cancer, overall and by hormone receptor subtype, among females in the Norwegian Offshore Petroleum Workers (NOPW) cohort. We also ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
With the introduction of the exchange-traded German wind power futures, opportunities for German wind power producers to hedge their volumetric risk are present. We propose two continuous-time multivariate models for wind ...
(Doctoral thesis / Doktoravhandling, 2021)
The polar oceans consist of open water, continuous ice covers and zones of broken ice floes of various sizes in the transition between water and ice. As the waves from the open ocean travel into the zone of ice floes, the ...
(Doctoral thesis / Doktoravhandling, 2021)
Submarine mass movements are important sources for tsunamis with potential destructive consequences at coastlines. A famous example from historical records is, for instance, the 1929 Grand Banks tsunami in Canada. This ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Deep Reinforcement Learning (DRL) has recently spread into a range of domains within physics and engineering, with multiple remarkable achievements. Still, much remains to be explored before the capabilities of these methods ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Background
Studies of mammalian CSF dynamics have been focused on three things: paravascular flow, pressure and pulsatility, and “bulk” flow; and three (respective) potential motive forces have been ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Many of the widely used models for description of nonlinear surface gravity waves, in deep or shallow water, such as High Order Spectral Method (HOSM) and Boussinesq-type equations, rely on the elimination of the vertical ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
This study presents wave measurements in the Marginal Ice Zone (MIZ) obtained from ship mounted sensors. The system combines altimeter readings from the ship bow with ship motion correction data to provide estimated single ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
We study the stability of a unique weak solution to certain parabolic systems with nonstandard growth condition, which are additionally dependent on a cross-diffusion term. More precisely, we show that two unique weak ...
(Doctoral thesis / Doktoravhandling, 2021)
In our modern society, with the bourgeoning of e-commerce and online streaming platforms, customers are overwhelmed by the choices. One important approach to solve this problem is recommender systems. Recommender systems ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
We study the dynamic wetting of a self-propelled viscous droplet using the time-dependent lubrication equation on a conical-shaped substrate for different cone radii, cone angles and slip lengths. The droplet velocity is ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
We investigate the probabilistic and analytic properties of Volterra processes constructed as pathwise integrals of deterministic kernels with respect to the Hölder continuous trajectories of Hilbert-valued Gaussian ...
(Doctoral thesis / Doktoravhandling, 2021)
Both in science and industry, the sizes of data sets are growing. It is not uncommon to encounter sets containing millions or even billions of measurements. Without appropriate tools for turning such enormous amounts of ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
A sharp version of a recent inequality of Kovalev and Yang on the ratio of the (H1)∗ and H4 norms for certain polynomials is obtained. The inequality is applied to establish a sharp and tractable sufficient condition for ...
(Doctoral thesis / Doktoravhandling, 2021)
The development of research and exploration in Arctic waters is very common nowadays. One of the environmental difficulties to carry out research in these regions is the icing of surfaces. After short periods of time, ice ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
System logs or log files containing textual messages with associated time stamps are generated by many technologies and systems. The clustering technique proposed in this paper provides a tool to discover and identify ...
(Doctoral thesis / Doktoravhandling, 2021)
Many important results in mathematics deal with the question of figuring out what objects are ‘the same’. One way of rigorously dealing with this is through the notion of isomorphic objects. However, it is sometimes better ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Structural reliability analysis is concerned with estimation of the probability of a critical event taking place, described by P(g(X)≤0) for some n-dimensional random variable X and some real-valued function g. In many ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Operating in energy and commodity markets require a management of risk using derivative products such as forward and futures, as well as options on these. Many of the popular stochastic models for spot dynamics and weather ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Plants and insects use slender conical structures to transport and collect small droplets, which are propelled along the conical structures due to capillary action. These droplets can deposit a fluid film during their ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Graph products of groups were introduced by Green in her thesis [32]. They have an operator algebraic counterpart introduced and explored in [14]. In this paper we prove Khintchine type inequalities for general C⁎-algebraic ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Coupled partial differential equations (PDEs) defined on domains with different dimensionality are usually called mixed-dimensional PDEs. We address mixed-dimensional PDEs on three-dimensional (3D) and one-dimensional (1D) ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Two-phase oil and gas flow were simulated in an entirely eccentric annulus and compared with experimental data at horizontal, 4, 10, and 90° inclination. The gas-phase was sulphur hexafluoride and the liquid phase a mixture ...
(Doctoral thesis / Doktoravhandling, 2021)
In this thesis, two-phase flow in an annular pipe geometry is studied using an open-source software known as OpenFOAM. The data collected through the simulations in this thesis are compared to experimental data collected ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
This paper considers data-based real-time adaptive Fault Detection (FD) in Grid-connected PV (GPV) systems under Power Point Tracking (PPT) modes during large variations. Faults under PPT modes remain undetected for longer ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
This work introduces the deconvolution as a technique to reconstruct missing information in data. While the method was originally developed for ocean waves, it will be useful in a wider range of applications where gaps in ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
A novel Dynamic Kernel PCA (DKPCA) method is developed for process monitoring in nonlinear dynamical systems. Classical DKPCA approaches still exhibit vague linearity assumptions to determine the number of principal ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
We introduce a mean counting function for Dirichlet series, which plays the same role in the function theory of Hardy spaces of Dirichlet series as the Nevanlinna counting function does in the classical theory. The existence ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
The present study was originally motivated by some intriguing exact solutions for waves propagating in nonuniform media. In particular, for special depth profiles reflected waves did not appear and ray theory became exact. ...
(Doctoral thesis / Doktoravhandling, 2021)
Rogue waves are unexpected and unusually larger waves than their surrounding and can be dangerous to ship and offshore structures. In normally distributed wave fields also known as Gaussian sea, rogue waves actually exist, ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Publication bias and p-hacking are two well-known phenomena that strongly affect the scientific literature and cause severe problems in meta-analyses. Due to these phenomena, the assumptions of meta-analyses are seriously ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Experimental and numerical evidence have shown that nonuniform bathymetry may alter significantly the statistical properties of surface elevation in irregular wave fields. The probability of “rogue” waves is increased near ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
We introduce a rough perturbation of the Navier–Stokes system and justify its physical relevance from balance of momentum and conservation of circulation in the inviscid limit. We present a framework for a well-posedness ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
In the setting of one-dimensional polynomial jump-diffusion dynamics, we provide an explicit formula for computing correlators, namely, cross-moments of the process at different time points along its path. The formula ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Background
The overall aim of this study is to examine the effect of prenatal maternal anxiety on birthweight and gestational age, controlling for shared family confounding using a sibling comparison design.
...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Background
Several central nervous system diseases are associated with disturbed cerebrospinal fluid (CSF) flow patterns and have typically been characterized in vivo by phase-contrast magnetic resonance ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Rational quartic spectrahedra in 3-space are semialgebraic convex subsets in R3 of semidefinite, real symmetric (4×4)-matrices, whose boundary admits a rational parameterization. The Zariski closure in CP3 of the boundary ...
(Journal article / Tidsskriftartikkel / PublishedVersion, 2021)
We investigate the space-time regularity of the local time associated with Volterra–Lévy processes, including Volterra processes driven by α-stable processes for α∈(0,2]. We show that the spatial regularity of the local ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Abstract We study C*-algebras generated by left regular representations of right LCM one-relator monoids and Artin–Tits monoids of finite type. We obtain structural results concerning nuclearity, ideal structure and pure ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Machine learning has recently become a promising technique in fluid mechanics, especially for active flow control (AFC) applications. A recent work [Rabault et al., J. Fluid Mech. 865, 281–302 (2019)] has demonstrated the ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
A cohomology class of a smooth complex variety of dimension n has coniveau at least c if it vanishes in the complement of a closed subvariety of codimension at least c, and it has strong coniveau at least c if it comes by ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
We study the computational complexity of three representations of irrational numbers: standard Baire sequences, dual Baire sequences and contractors. Our main results: Irrationals whose standard Baire sequences are of low ...
(Journal article / Tidsskriftartikkel / SubmittedVersion, 2021)
We propose a refined version of the stochastic SEIR model for epidemic of the new corona virus SARS-Cov-2, causing the COVID-19 disease, taking into account the spread of the virus due to the regular infected individuals ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Physical inactivity, high postmenopausal body mass index, alcohol consumption and use of menopausal hormone therapy are established risk factors for breast cancer. Less is known about whether these factors influence the ...
(Journal article / Tidsskriftartikkel / SubmittedVersion, 2021)
We analyse forward prices observed at the Fishpool market, and propose a two-factor continuous-time stochastic process for modelling the time dynamics. The data analysis reveals that the two factors can be assumed to be a ...
(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2021)
We present skweak, a versatile, Python-based software toolkit enabling NLP developers to apply weak supervision to a wide range of NLP tasks. Weak supervision is an emerging machine learning paradigm based on a simple idea: ...
Accurate discretization of poroelasticity without Darcy stability -- Stokes–Biot stability revisited
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Abstract In this manuscript we focus on the question: what is the correct notion of Stokes–Biot stability? Stokes–Biot stable discretizations have been introduced, independently by several authors, as a means of discretizing ...