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8
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3answers
113 views
+150

Fluids with critical point at ordinary temperature and pressure

Are there any fluids with critical point near STP or that are supercritical at STP? If not would it be feasible to design a molecule for a substance with critical point near STP using theoretical/...
-1
votes
0answers
9 views

Speed of sound at phase transition — does percolation theory describe it?

I was discussing with a friend whether we expected liquid water or ice to have a higher speed of sound, near freezing; we figured it would be water since it was more dense. It turned out to be ice (by ...
2
votes
4answers
406 views

Why does solid turn to liquid deep in the Earth? [duplicate]

Usually pressure decreases inter-molecular movement thereby keeping the substance in solid state. Given this, why do the earth's crust and mantle, which are both solid, turn into a liquid outer core, ...
-3
votes
0answers
29 views

Renormalization Group in Condensed Matter [closed]

Are RG calculations done only in the vicinity of a phase transitions in cond-matt?
2
votes
0answers
24 views

Is the free energy density analytic in temperature at the Kosterlitz-Thouless phase transition?

I know that the KT transition is infinite-order so the free energy density is a smooth (i.e. infinitely differentiable) function of temperature, but is the function actually analytic at the critical ...
2
votes
0answers
41 views

Why are phase transitions discrete?

It seems like there is no "in-between" for the phases of matter; it can be "solid" or "liquid", but what about the in-between? Why is there no spectrum of matter between the phases (e.g. a range of ...
27
votes
5answers
2k views

Why does a critical point exist? [duplicate]

I still cannot fully comprehend the essence of a critical point on phase diagrams. It is usually said in textbooks that the difference between liquid and gaseous state of a substance is quantitative ...
0
votes
0answers
15 views

Quantum phase transition from a gapless spin liquid to a gapped topological spin liquid

What do we know about a quantum phase transition from a gapless spin liquid to a gapped topological spin liquid? Is there any model to realize such a transiton? Thanks!
0
votes
0answers
11 views

experimental phase diagram of Li_xFe_(1-x)O system

From material project, we could get the computational phase diagram of Li_xFe_(1-x)O system. However, there does not seem to be sources for the corresponding experimental phase diagram. Where could we ...
1
vote
1answer
54 views

Rotation of superfluid

I have two questions related to rotation of superfluids. Firstly, what is the main reason that superfluid cannot rotate as a whole object ? (I found that it is true in Landau's Statistical Physics but ...
30
votes
3answers
27k views

First and second order phase transitions

Recently I've been puzzling over the definitions of first and second order phase transitions. The Wikipedia article starts by explaining that Ehrenfest's original definition was that a first-order ...
0
votes
1answer
31 views

Quantum ising/heisenberg model, states representation

I am working with a hamiltonian which looks like this (Heisenberg model) I have made a program which computes this hamiltonian using Pauli matrices (spin 1/2). My working space is then the tensor ...
0
votes
2answers
75 views

Why does hot water freezes faster than normal water? [duplicate]

What is the reason behind hot water gets Freezes faster than normal water when we keep both the hot and normal water together in freezer ?
6
votes
2answers
239 views

does a rocking kettle cause the water to boil more slowly?

When I boil water in the kettle on my electric stove, sometimes it rocks back and forth making an annoying sound at a frequency of about 6Hz. When that happens, I move the kettle slightly to make it ...
5
votes
0answers
56 views

Are second-order phase transitions always scale/Lorentz invariant?

I know that both scale invariance and Lorentz invariance typically emerge at second-order phase transitions, but is there a proof or a counterexample? (I know that it's believed that any theory that ...
0
votes
1answer
292 views

Why is specific volume of saturated water greater at 1 MPA than at 0.1 MPA during the phase change process?

Why is specific volume of saturated water greater at 1 MPA than at 0.1 MPA during the phase change process? check out the T-V diagram here in the link. http://www.ohio.edu/mechanical/thermo/Intro/...
13
votes
2answers
422 views

Phase transition water

The water-gas phase transition is said to be similar to the ferromagnetic-paramagnetic phase transition (same set of critical exponents = same universality class). In the former case the order ...
0
votes
0answers
13 views

Is there a way to calculate the change in temperature of water in a vacuum?

My understanding is that water boils when the vapor pressure is reached and then, at some point, freezes. Is there a way to relate the vacuum pressure to the temperature of the water until it changes ...
4
votes
2answers
46 views

In the Landau theory of phase transitions, is the order parameter a thermodynamic variable of state?

In the Landau theory of phase transitions, one typically considers a "free energy" $F$ as a function of the temperature $T$ and the "order parameter" $\psi$: $F(T, \psi)$. For the sake of clarity, ...
5
votes
4answers
201 views

Does salt speed the transition of water from ice to vapor?

In a dry environment that is somewhat below the freezing point, water ice will, over time, sublimate to vapor. If you scatter salt across the ice, some of the ice will melt, and the melted water will ...
5
votes
1answer
419 views

Does a negative line tension in a 3-fluid immiscible interface make sense?

This question is inspired by this question/answer pair: Is this formula for the energy of a configuration of 3 fluids physically reasonable? Consider three immiscible fluids forming contact surfaces, ...
1
vote
1answer
217 views

Helmholtz Free Energy vs Gibbs Free Energy in Landau Theory

When I was studying thermodynamics potentials for the first time, I learned that keeping the pressure and the temperature constant, the Gibbs Free Energy is a minimum, also, if we maintain the ...
17
votes
4answers
612 views

Why does water ($\mathrm{H_2O}$) only have two distinct fluid phases?

Water (and other substances) can exist in many distinct solid phases (with different crystallic micro-structure), but only in two fluid phases - liquid and gaseous, in which the molecules are oriented ...
1
vote
0answers
26 views

Correct terminology or way to refer to the 2 “types” of ice sublimation

I'm trying to get the right terminology for various forms of phase change. I am familiar with the phase change / triple point diagram for water, and we have various terms for the transition of a ...
-1
votes
2answers
121 views

Can any material be a fluid?

Please find mistakes in the following (if found): Since any material can change its phase to a gaseous, supercritical, liquid or fluid state any material can be considered as a fluid, so it is wrong ...
0
votes
3answers
454 views

How to calculate critical temperature of the Ising model?

Can someone name a paper or book which calculates the critical temperature of the Ising model from scratch? It might be a book and should contain the necessary prerequisites. I have had a basic course ...
1
vote
0answers
60 views

Exact Solution of Ising Model in Open Boundary condition

What will be the exact expression of the partition function for 1d Ising model, if we consider open boundary case (This implies that the last spin in the sequence does not interact with the first spin)...
1
vote
0answers
50 views

Confusion on meaning of fugacity in scientific publication

in my research project in statistical mechanics, in the context of phase transition and condensation, I was reading the seminal paper of Yang and Lee titled: "Statistical theory of equations of state ...
1
vote
1answer
31 views

Help with understanding result from publication on phase transition

In my current research project in statistical mechanics, in the context of phase transition and condensation, I was reading the seminal paper of Yang and Lee titled: "Statistical theory of equations ...
2
votes
2answers
197 views

What actually makes boiling happen?

Boiling can be breezed over easily with a few rudimentary diagrams and a couple equations, but I seek a deeper explanation. The definition of boiling is that the vapor pressure in the liquid is ...
1
vote
0answers
30 views

Why do the singularities of the thermodynamic functions expected to be non-negative powers?

I am going through the first chapter of Exactly Solved Models in Statistical Mechanics. On page 4, at the end of section 1.1 it is said that: I would like to know the basis of this expectation. ...
0
votes
0answers
21 views

2D slab model for LJ potential

I have a program implementing a LJ(Lennard-Jones) molecular Dynamics(MD) simulation with isokinetic thermostat. I want to modify that program to study the phase characteristics of LJ particlesin 2D ...
3
votes
1answer
35 views

Effectiveness of phase-change materials vs water for heat storage?

I'm trying to understand the benefit of specialized phase-change materials vs. water for absorbing heat in a home during the day. It's my understanding that selecting phase-change materials whose ...
0
votes
0answers
45 views

What is Hastatic order?

I've looked around for a proper definition and defining terms for this property. Can anyone explain Hastatic order? Is there a proper theory as to why it occurs? (Also, I don't have points to create a ...
6
votes
3answers
769 views

Solidification by the application of heat

When you add heat to a liquid (or a fluid), can it be solidified? If not, why in the world does an egg's stuffs become solid (or at least no more a liquid) when you 'boil' it in water?
0
votes
1answer
21 views

What is the vapour pressure of carbon at room temperature?

The vapour pressure of carbon at 3642°C is one atmosphere (this is the sublimation temperature given in Wikipedia). At lower temperatures, the vapour pressure will be less, but of course it will ...
1
vote
0answers
23 views

Master curve of the 3D Ising model

I am currently doing some grand canonical Monte Carlo simulations for LJ particles and my professor has asked me to map the normalized probability distribution of density on to a master curve of the ...
0
votes
0answers
30 views

Electroweak phase transition

Is it true that when the temperature of the universe was greater than ~200GeV the Higgs did not have any nonzero vacuum expectation value, hence all the particles were massless? So if one calculates ...
7
votes
1answer
306 views

Phase Transition at Zero Temperature (Not QPT)

As is well known the Ising model exhibits a phase transition, except the one dimensional case in which the phase transition occurs strictly at $T=0$. Now I have always thought that this makes the case ...
3
votes
0answers
35 views

What is the Kosterlitz -Thouless transition?

I couldn't find any simple texts explaining the Kosterlitz-Thouless transition. More specifically can someone explain the role of vortices in the transition. edit: links explaining the transition in ...
0
votes
0answers
28 views

Susceptibility at a first-order phase transition

I have two questions about first-order phase transitions: 1) is the susceptibility divergent at a first-order phase transition? 2) if yes, does it diverge in a universal way as in continuous phase ...
5
votes
1answer
88 views

How to understand the idea of functional renormalization group?

I have been looking at how to use the functional RG method in many-body systems, but I don't quiet get the idea of it, it look different from Wilson's RG approach (eg. why shall we integrate out the ...
1
vote
1answer
30 views

Why do $C_p$, $\alpha$ and $\kappa_T$ all approach to infinity when two phases coexist at the mean time?

My textbook (writed by Chinese) says that when two phases of a system coexist at the same time, this system's isobaric thermal capacity $C_p=T(\frac{\partial S}{\partial T})_p$, coefficient of ...
1
vote
1answer
50 views

Adiabatic transition from superfluid to Mott insulator?

I have a question about the dynamical passage from superfluid to Mott insulator state in the Bose-Hubbard model. Is it possible to go from superfluid region to the Mott insulator by changing the ...
9
votes
4answers
308 views

What is the real cause of the boiling (forming of bubbles) of water?

I've got a question about the boiling of water. I'm a first year physics student and from the Netherlands. I've searched alot about the boiling of water and this confused me. Everyone said something ...
0
votes
0answers
19 views

Role of heat flux on bubble size

This is sort of related to this question, in that the question was spawned from the same question on Worldbuilding. Say you have a relatively shallow open pool of water (a pot or pan). When the ...
-5
votes
1answer
45 views

What phase is water at 262C and 15bar? [closed]

what phase is water at 262C and 15bar? at which conditions and above can we be sure that the water is totally gaseous? can I see a water phase graph for 262C and 15bar?
6
votes
1answer
100 views

FCC-to-BCC phase transition in NaCl, Buckingham or Lennard-Jones potentials?

Background The transformation from B1 (face centered cubic (FCC) type) to B2 (body centered cubic (body centered cubic (BCC) type) structures is one of the best documented high pressure phase ...
8
votes
1answer
151 views

Why does Landau theory not fail when dealing with a first order phase transition?

Here is a problem where I can do the calculation, but I am not understanding the philosophy behind it. It is about Landau theory: The Landau theory of phase transitions is based on the idea that the ...
0
votes
0answers
21 views

What is Phase Transition in Cosmology and where does the energy of it comes from?

There are different theories on how our universe will end. The Big Crunch, The Big Rip, The Big Freeze but I also heard about Phase Transition on a space science program on a science channel, what ...