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Questions tagged [phase-transition]

A phase transition is a change in the nature of a phase or in the number of phases of a system as a result of a change in the external conditions. Examples: melting/freezing, vaporization/condensation, ferromagnetic transition, superconducting transition.

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Is there a temperature-pressure phase diagram of carbon dioxide for the lowest temperatures and pressures?

The image above will probably be well known to visitors of Wikipedia on CO$_2$. But is there a temperature-pressure phase diagram of CO$_2$ for still lower temperatures and lower pressures as well ?...
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Pressure of a liquid when discussing boiling

It's said that at boiling point the pressure of the liquid is equal to the pressure of its vapor. That way, bubbles can form in the liquid phase. However, unless I'm mistaken, while the pressure of a ...
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What is the precise definition of phase? [duplicate]

the phase of matter can be understood by landau argument and/or with topology. how ever, I cant find anywhere a precise definition of what phase is?
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If states of matter transition discretely or continuously

When you see phase diagrams for states of matter, they typically look something like this: This shows discrete changes from one state to the next. I am wondering though if it is actually a discrete ...
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Quantum phase transitions in a finite lattice

Sachdev begins his book on Quantum Phase Transitions by asserting that, for a system on a finite lattice, the ground state energy of a Hamiltonian H(g) (where g is some coupling) is a smooth, analytic ...
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What is the broken symmetry in a phase transition into Anderson localisation?

Anderson localisation is a state of matter where there is no diffusion of particles because of randonmness in the potential landscape. The wavefunction is localised, i.e. exponentially dropping to ...
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Dynamic critical exponents of Curie-Weiss model

I'm looking for the dynamical exponent z (relaxation time) of the Curie-Weiss - Ising like model with infinite-range interactions ($J \sim 1/N$). Does anyone know a reference where this was solved? ...
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Why a superconductor expel magnetic lines of force from inside completely when cooled below critical temperature?

Suppose a superconductor which is in a normal state (i.e. $T>Tc$) is subjected to a magnetic field. As soon as magnetic field switched from 0 to some value, eddy currents will develop on the ...
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Phase Transitions from a Bayesian Perspective of Statistical Mechanics

I have been reading papers by E.T. Jaynes recently about viewing all of statistical mechanics as just Bayesian inference applied to physics. (For an introduction: https://journals.aps.org/pr/abstract/...
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Why is boiling a non-equilibrium process? [closed]

Boiling is a non-equilibrium process. Which equilibrium (mechanical, chemical and thermal) are not maintained during boiling and why?
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Classical Heisenberg Model Using Mean Field Approximation

Suppose we have the Classical Heisenberg Model of N spins $\vec S_i$ (unit vectors), external field $\vec H // \hat z $ $$ {\cal{H}} = -2J \sum_{<i,j>} \vec S_i \cdot \vec S_j - gμ_B \sum_i \...
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System-size dependent phase transitions

I noticed that some physical phenomena require a system of size above some critical value to be observed. Two examples I know are: For a single-atom gold wire, there is a critical number of atoms to ...
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Trouble with critical expotent β

In the context of the Landau Theory of phase transitions, applying the mean field theory in an attempt to describe transitions such as the Nematic - Isotropic, the Landau energy density is given by $...
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Susceptibility in Bifurcations

In dynamical systems a bifurcation describes the phenomenon where, as a system parameter is varies, a qualitative property of the system might be altered. Similarly, in statistical physics, a ...
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How to numerically calculate Fisher zeros?

The main quantity in the study of dynamical quantum phase transition (DQPT) is Loschmidt echo amplitude defined as $G(t)=\langle \Psi_{0}|\Psi_{0}(t)\rangle=\langle \Psi_{0}|e^{-iHt}|\Psi_{0}\rangle$...
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Why does ice form when you break the seal on a very cold bottle of water? [duplicate]

I put a sealed bottle of commercially available drinking water in a freezer and let it get really cold, but not frozen solid. The water is not carbonated. Then I remove the bottle and place it in a ...
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Evaporation amount of water for a Storm [closed]

How much water from the ocean is evaporated for a storm over water? I am trying to figure out what conditions will cause the most evaporation or how to calculate the amount of water evaporated for a ...
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What is an intuitive explanation of wave ordering vector $Q$? (Pierls Instability)

How does the wave ordering vector $Q$ order a CDW? I saw this vector while studying the following system. We have a system with $N$ sites and $N/2$ spinless fermions and system is in the fully ...
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Free energy second derivative at critical point of gas-liquid transition

In 2 lines this book says that the second derivative of the thermodynamic Helmholtz free energy density $a\left(\rho,T\right)$ with respect to density of a one-component fluid, $\rho$, when we ...
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Can phase transitions occur in open systems?

Is it possible that in open systems can occur phase transitions if the required conditions (i.e., temperature and pressure) are met? Are there examples?
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Heat Capacity relations on phase transition

The question is about proving the following relation : Cs=(dq/dT)s=Cp-(αVΔH/ΔV) For the first order phase transition,where clausius equation applies. Where Cs=heat capacity along coexistence curve ...
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What is the Graceful exit problem?

During my studies on Extra-dimension BSM models, I encountered some discussion about the "Graceful exit problem" some model suffers in cosmology. In particular, in this paper https://arxiv.org/abs/...
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Are saturation temperature and boiling point same thing?

In my view they both are same thing. Boiling point is the temp at which vapor pressure of water becomes greater than pressure outside vessel. Liquid water change it's phase during this. And. At a ...
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Definition of boiling point of water

As we all know at normal boiling point, vapor pressure of water is equal to atmospheric pressure. Vapour pressure of water is pressure exerted by its vapor(in dynamic equilibrium with water) on the ...
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Topological soliton objects in Minkowski v.s. Euclidean spacetime?

What makes the distinctions between the soliton objects in Minkowski or in Euclidean spacetime? It looks that usually, the Euclidean path integral is easier to be performed in many cases. In fact, ...
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Why does it become difficult to sample configuration during a phase change in Monte Carlo simulation?

I recently read in a paper that Monte Carlo integration is very slow near phase transitions. I couldn't understand the concept properly. The paper is Phys. Rev. B 95, 035105 (2017).
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Violation of Gibbs Phase Rule?

According to Gibbs phase rule, only one intensive property is required to completely specify a simple compressible system which is in a liquid/vapor equilibrium. F = 2 + C - P For a pure substance, ...
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Is it possible to force a temperature difference using evaporation/condensation cycle?

Here's a picture of my supposed "cooler": The apparatus has following properties: The bottom and upper part: thermally very conductive Side: thermally very non-conductive The "some liquid" is an ...
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What goes on inside a kettle if you can't get to it after the whistling begins? [closed]

Let's say you can't get to the kettle for a few minutes after the kettle starts to whistle. Presumably the temperature of the water inside the kettle is still rising, past boiling point If there wasn'...
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What's measured by weighting a fluid?

Suppose you have a glass of water at room temperature. Now suppose you put the glass of water on a weighting scale. What the quantity actually measures ? I have read that in fluids are basically lots ...
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How presence of metastable state ensure that there is first order phase transition?

Recently, I took a lecture in which professor showed a graph which was similar to following figure Professor told that if there is a metastable state, it means that there must be some kind of first ...
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How does the virial expansion converging, mean that there is no phase transition?

I have a question regarding how the virial expansion relates to phase transition. I watch the lecture https://www.coursera.org/learn/statistical-mechanics/lecture/1a5Di/tutorial-3-algorithms-exact-...
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Is partition function algorithm-dependent or configuration-dependent?

I am reading this resource to learn statistical mechanics: http://blancopeck.net/Statistics.pdf I am trying to learn about the partition function, which as I understand it, is equal to the number of ...
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Why doesn't Coleman-Mermin-Wanger theorem contradict phase transitions in systems with 1D reaction coordinate?

How does both hold: Coleman-Mermin-Wanger theorem continuous symmetries cannot be spontaneously broken at finite temperature in systems with sufficiently short-range interactions in dimensions ...
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Phase transition in a generalised SYK model

Crossposted from math.stackexchange. (Link: https://math.stackexchange.com/questions/2848558/is-this-function-meromorphic) Question Let $$e^{g\left(\tau,T,J_1,J_2\right)}=\frac{2}{\left(\frac{J_1}{...
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Why does evaporation cause cooling?

I am aware that the evaporation process causes cooling in the remaining liquid, but why? If anyone can give me the maths and or equations to prove / show this I would be most appreciative.
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What determines strength of a phase transition?

Consider a phase transition involving a scalar field $\phi$. After including temperature corrections to a typical Mexican hat potential, one obtains, $$ V(\phi, T) = D ( T^2 - T_0^2) \phi^2 - ET\phi^...
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Phase of refrigerant when entering evaporator?

In the diagrams for refrigeration cycle(vapour-compression), the refrigerant at the inlet to the evaporator lies under the vapour dome i.e partly vapour and partly liquid. Now i have been studying ...
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Classical statistical model based on group multiplication

For a (finite) group $G$, consider the following classical statistical model on a 2 dimensional lattice with oriented edges: Each edge carries a classical degree of freedom that can take values in ...
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Is there an intuitive reason as to why there is no phase transition to get to a degenerate Fermi gas?

Cooling a bosonic gas leads to a phase transition into the Bose-Einstein condesate. This is characterised by a symmetry broken ( U(1), by choosing a specific phase for the macroscopic wavefunction) ...
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Phase transition and energy conservation inside neutron star

I'm stuck at the moment with this simple question: If a phase transition from hadronic to quark matter of 1st order with a big jump in the energy density occurs inside a neutron star one can get ...
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Data for plotting phase changes in water

I want to plot phase diagrams of water that show its density, heat capacity, and entropy as it undergoes various first order (discontinuous) phase transitions with increasing temperature. I'm ...
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What would happen to a 10 meter sphere of room temperature water if released into space?

Imagine that we had a space station with a relatively large hangar, and we allowed a ball of water to accumulate that had a 10 meter diameter and a water temperature of 20C. While the hangar is ...
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Why does a vanishing energy gap indicate a phase transition?

More concretely: When looking at the Ising model in the description of Bogoliubov fermions, we get an explicit expression for the energy gap, that vanishes for a particular value of the magnetic field....
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Why does $[H,N]=0$ violate with superfluid phase judgement $\left<b\right>=0?$

I'm working with the standard Boson Hubbard model. It's Hamiltonian is defined in Fock space and commutes with total particle number N. $$[{{\hat H}_{BH}},\hat N] = 0$$ So I can simultaneously ...
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Does carbon form a gas in the absense of oxygen?

If I take pure carbon and heat it in an inert atmospher, at what temperature will it vaporize into carbon gas?
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As the universe expands, do we have any reason to suspect further separation of the fundamental forces/interactions?

At some point, all four forces were one force. (another question: what exactly does that mean?). At some point gravity and the strong force separated out leaving the electroweak force. Then the ...
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Apparition of scale invariance

When did "scale invariance" started to be seen as an important concept in the theory of phase transition? Phase transition and critical points started to be investigated in earnest in the middle of ...
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Symmetry breaking - mixed state in $T\rightarrow 0$ limit

In the quantum$^1$ system with a continuous symmetry (in the Thermodynamic limit) relating the ground states $\newcommand{\ket}[1]{\left|#1\right>}\{\ket{\theta}\} \newcommand{\bra}[1]{\left<#1\...
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Correlation length at low temperatures?

The correlation length gives (approximately) the distance over which a spin flip has an effect. For systems with ordered phases, at low temperatures the correlation length is then small (since a ...