Questions tagged [soft-matter]
Soft-matter is a vast field of research at the interfaces between physics, chemistry and biology. It consists in the study of the physical properties of composite objects described by a characteristic energy scale of the excitations of a few room temperature thermal energy.
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Resources on Phase Ordering Dynamics and Non-Linear System
I am doing a course on Non-Equilibrium Physics. Prof. was initially following Strogatz but has now started teaching Phase ordering dynamics, Cahn-Hillard equation and all?
I can't seem to find a good ...
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Why do stones in a garden rise to the surface?
Why do stones in a garden rise to the surface?
I haven't done my own research on the subject, but experienced gardeners seem to suggest that, even if the garden is cleaned from stones, they reappear ...
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Time derivative term in Navier Stokes equation for fluid in porous media
I was reading the research paper Homogenization of peristaltic flows in piezoelectric porous media and came across the hydrodynamic equation:
$$\mu \nabla^2 v^f -\underline{ \rho_f (\dot{v}^f + w \...
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I want to know: what is the principle that causes this phenomenon? [closed]
The effect of fractal fingering can be observed if a droplet of an ink-alcohol mixture is deposited onto diluted acrylic paint. How are the geometry and dynamics of the fingers influenced by relevant ...
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Non-linear corrections to the Oseen-Frank free energy density
A nematic liquid crystal is essentially a fluid of long, rod-like molecules whose average orientation is dictated by a vector field $\mathbf {\hat {n}} $. The so-called Frank-Oseen (free) energy (...
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How can we calculate deposition flux in terms of monolayer per second?
In the nucleation and growth theory, I read the unit of deposition flux of atoms in a substrate in terms of monolayer per second. But could not figure it out how to calculate the flux in terms of ...
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Question about 1D Percolation Theory [closed]
I am currently reading "Introduction to Percolation Theory" by Stauffer and Aharony and am doing the problems. Question 2.2 wants me to calculate a closed-form expression for the $k$-th ...
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Homotopy group for spin-1 BEC
Homotopy group can be used to classify topological defects. The procedure is
Find the Lie group $G$ that leaves the free-energy functional invariant when transforming $\psi$, where $\psi$ is the ...
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How to specify the dimension of the simulation box to run molecular dynamics simulation?
I want to study the physical properties of binary liquids, molecular dynamics simulation using gromacs software is used to simulate the liquids. To set the initial coordinate configuration, how do we ...
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Converting order parameter to director (nematics)
If I have a differential equation for the order parameter of a uniaxial nematic, like
$\frac{\partial S_{\alpha \beta}}{\partial t} = f(S_{\alpha \beta})$,
for
$S_{\alpha \beta} = S(n_{\alpha}n_{\beta}...
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Scaling of the shear rate with pipe diameter
In a laminar flow regime the flow profile in a pipe should be given by:
$$ v(r) = \frac{\Delta p}{4 \eta l} (R^2-r^2)$$
If we assume that the radial shear rate is a meaningful indicator for the ...
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What determines water flow speed in the Clever Dripper coffee maker?
Recently James Hoffmann (a YouTuber that has a coffee channel) posted a video on 'the ultimate technique of using the Clever Dripper'. Many users of this brewer have experienced 'choking' of the brew, ...
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Why is the energy required to bend a flat bilayer membrane to vesicle independent of its radius?
Imagine that we have a flat bilayer sheet (let it be a disc-shaped bilayer) lipid membrane. When I naively think about this system being bent to form a vesicle (closed bilayer membrane), my intuition ...
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Using Persistence length to establish straightness of position data
In the following picture I am showing 3D position data for 4 different tracks just to illustrate how the tracks looks like.
As we can see that we have all kind of behaviors occurring from helical ...
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Force balance that includes solution gradient
In the provided figure, pistons seal the top and bottom of a cylinder of cross sectional area $A$ containing solution, which is split into two chambers via a semi-permeable barrier. The initial number ...
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