The tag has no usage guidance.

learn more… | top users | synonyms

2
votes
4answers
384 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
25 views

Renormalization Group in Condensed Matter [on hold]

Are RG calculations done only in the vicinity of a phase transitions in cond-matt?
2
votes
0answers
22 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
37 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 ...
0
votes
0answers
14 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!
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
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 ...
0
votes
2answers
74 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 ?
0
votes
1answer
29 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 ...
1
vote
1answer
53 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 ...
4
votes
0answers
54 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
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
200 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 ...
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
vote
0answers
58 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 ...
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
19 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
44 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 ...
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 ...
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
29 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 ...
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
98 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 ...
1
vote
1answer
40 views

What is the source of the Curie point?

I'm seriously revisiting my knowledge on magnetism, and the Curie point has been both enlightening and mystifying. I understand what it does ((ferro)magnetism disappears above it), and have a faint ...
0
votes
0answers
39 views

How to deduce the modified Flory-Huggins equation in this form?

In the paper of "Solution Properties of Poly(N-isopropylacrylamide)" (M. Heskins and J. E. Guillet, Journal of Macromolecular Science: Part A - Chemistry, Vol. 2, Issue 8, pages 1441-1455, 1968), they ...
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 ...
0
votes
0answers
35 views

The driving force for first order phase transition

The driving force for the solidfication is said to be the free energy difference, but phase transition actually happens due to change of temperature toward the critical temperature. It seems that ...
0
votes
0answers
37 views

Phase transition in mean field theory Ising model

For the Ising model mean field theory is supposed to give quantitatively correct answers in dimensions>=4. I have written code to compare the results of mean field theory to a 4D or 5D Ising model and ...
10
votes
1answer
955 views

What leads to the existence of critical temperature?

We know that $T_c$ is the temperature above which no amount of pressure could force a gas to liquefy. But why is this? Somehow I don't buy the point that the gas molecules exert too much pressure ...
6
votes
1answer
247 views

Melting ice: reversible or irreversible?

I am looking into whether the melting of ice (or any substance for that matter) at constant pressure and temperature is reversible or irreversible. Different sources say different things, and it may ...
0
votes
0answers
12 views

Temperature dependence of phase transition in Quantum Hall Effect

Most phase transitions have a distinct critical temperature, depending on the parameters of the system. For example, the critical temperature of Bose-Einstein condensation depends on the particle ...
15
votes
2answers
503 views

What is “Dynamical phase transition”?

What is "Dynamical phase transition"? It is a fancy notion now. But what exactly does it mean? What is the difference between it and the conventional phase transition?
1
vote
0answers
23 views

Kerr-Newman Black Holes' Phase Transitions in De Sitter Space

At $J=km^2$ Kerr black holes' specific heat shows infinite discontinuity. Therefore as Kerr black holes' angular momentum gets close to $km^2$ where $k$ is determined by Kerr-Newman metric and $m$ is ...
0
votes
0answers
15 views

Example of a system that becomes anisotropic

I'm trying to find examples of physical systems that go through some type of phase transition in which they go from being isotropic to anisotropic. Perhaps some system that become more anisotropic as ...
77
votes
9answers
14k views

Why does matter exist in 3 states (liquids, solid, gas)?

Why does matter on the earth exist in three states? Why cannot all matter exist in only one state (i.e. solid/liquid/gas)?
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 ...
0
votes
0answers
32 views

How to calculate the critical temperatures of noble gases such as He, Ne, and Ar?

It seems like Lennard-Jones potential should be used to calculate the critical temperatures of such noble gases. But I'm not sure how to actually do it. Could anyone give me some ideas or suggestions ...
3
votes
1answer
59 views

What is special about many-body localization as opposed to Mott insulator

What is the difference between localization in a many-body localization system and localization in a Mott insulator? Is the difference that many-body localization is driven by disorder while Mott ...
4
votes
1answer
95 views

Why does a Heisenberg magnet break the O(3) symmetry in stead of SU(2)?

As stated in the question, why does a Heisenberg magnet break the $O(3)$ symmetry while degrees of freedom of the underlying spins are $SU(2)$?
1
vote
2answers
76 views

Are there alternatives to steam in thermal power stations?

'A thermal power station is a power plant in which heat energy is converted to electric power. In most of the world the prime mover is steam driven. Water is heated, turns into steam and spins a steam ...
2
votes
2answers
314 views

Why does Triple point exist?

In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases (gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium. Is the ...