What is Bose einstein: Definition and 38 Discussions
In condensed matter physics, a Bose–Einstein condensate (BEC) is a state of matter (also called the fifth state of matter) which is typically formed when a gas of bosons at low densities is cooled to temperatures very close to absolute zero (−273.15 °C or −459.67 °F). Under such conditions, a large fraction of bosons occupy the lowest quantum state, at which point microscopic quantum mechanical phenomena, particularly wavefunction interference, become apparent macroscopically. A BEC is formed by cooling a gas of extremely low density (about one-hundred-thousandth (1/100,000) the density of normal air) to ultra-low temperatures.
This state was first predicted, generally, in 1924–1925 by Albert Einstein following and crediting a pioneering paper by Satyendra Nath Bose on the new field now known as quantum statistics.
I tried to show this equality by explicitly determining what
$$ \overline{(\Delta \eta)^2} $$
is, but I got a totally different answer for some reason, here is my attempt to solve it, what did I miss?
For finding n, I believe that directly applying the above formula gives the results. But I am confused whether I have to put the value of given temperature T = 100K or the actual temperature Tc for Rb-87 at which BE Condensation occurs (i.e. 100 nK, which I got from a quick Google search)? Or do...
I am interested in whether or not Bose Einstein condensates have been realized for spin zero stable oxygen isotopes and if so, the maximum density achieved for these condensates. I understand that the quantum spins of oxygen 16 and oxygen 18 are both zero so such condensates would seem to be...
iam not getting why in bose statistics the number of ways to arrange ni particles in gi degenerate states is = (gi+ni-1) ?
and why do we divide by ni factorial , and gi factorial .
I'm not a physicist nor an academic, however, the world around me fascinates me. I was watching YouTube and came across an explanation of Bose Einstein condensate, and thought with less space between atoms that would potentially be a better target for creating new elements. So my question is...
Testing Quantum Gravity
Johan Hansson, Stephane Francois
(Submitted on 19 Oct 2017)
The search for a theory of quantum gravity is the most fundamental problem in all of theoretical physics, but there are as yet no experimental results at all to guide this endeavor. What seems to be needed is a...
Hello! I'm trying to simulate a one dimensional time independent BEC, I hope this is the right place to ask for help.
First of all, here's my code in Python.
import sys
import numpy as np
import matplotlib.pyplot as plt
if len(sys.argv) == 1:
niter = 100
elif len(sys.argv) == 2:
niter...
Hi,
I was given the following question:
Show that Bose condensation does not occur in 2D. Hint: The integral you will get when you write the formula for N is doable in elementary functions. You should find that that N ∝ ln(1 − e βµ).
I do indeed find that N ∝ ln(1/(1 − e βµ)) ∝ ln(1 − e βµ)...
We know that the average occupation number cannot be negative for all systems and chemical potential must be negative in Ideal Bose Gas. This fact leads us to arrive a conclusion for fugacity which is related by chemical potential, as I quoted below:
The restriction of the fugacity to the...
Dear All:
I'm trying to use fluctuation dissipation theorem to describe spontaneous photon emission process by electron-hole recombination in semiconductor material.
I notice that all the references using such a method considers the dipole's degree of freedom separately, for example in x, y, z...
Hi everybody, I was doing one asignment form class, I was tasked to prove that in one system, the arimetic mean of FD and BE distributions is equal to MB's distribution for undishtingable particles.
After doing the numbers I found out that it actually was, but I don't know why this happens, can...
Homework Statement
Explain the conditions under which Bose-Einstein condensation occurs and show this happens for density ##\rho \equiv N/V > \rho_C(T)##, where $$\rho_C(T) = A(kT)^{3/2} \int_0^{\infty} \frac{x^{1/2}}{ e^x − 1} dx .$$
Suppose the energy of the particles on the lattice is now...
If say a hundred or more objects, at a human scale, are connected by a string, and they can be made to synchronize in an oscillation, could that be considered a bose einstein condensate?
Hi,
my course just provided an introduction to Bose-Einstein Condensation.
I was told that this phenomenon occurs when the temperature of Bosons go under a certain critical temperature T_{c} > 0K. At absolute zero, all the Bosons go into the condensed phase.
However, at temperatures...
Homework Statement
We were asked to try to make a theoretical description of the following phenomenon:
Imagine a 2D Bose Einstein condensate in equilibrium in an harmonical trap with frequency ω. Suddenly the trap is shifted over a distance a along the x-axis. The condensate is no longer...
If time is constantly moving the direction of increasing entropy and quantum systems are time symetric then how do macropscopic entanlged systems such as bose-einstein condensates relate temporally to themselves and larger systems of which they might be subsets? Because BECs are large enough to...
Hi.
For a Bose gas, my textbook states that below the critical temperature, which is given by n(λth)3/(2S+1)=2.612, the fugacity z=eβμ≈1.
Why is this? The most basic explanation possible would be ideal, as I only need the rough idea.
Thanks! :smile:
Hello there
I love physics, so I normally read a lot of physics books. I am fascinated about BECs and their possible applications. I've read about BECs and BEC vacuum theory, also that is possible to create black holes in superfluids (as BEC) using sound (sonic black holes).
As far as I know...
Hello,
I was hoping someone might be able to give a approachable explination of the Gross-Pitaevskii equation. All the sources I've been able to find seem to concentrate on the derivation, and I don't have the physics background to follow. From what I understand, however, is that the GP...
They say ZPE is the energy of the system at 0 K due to vibrations and even though the Schroedinger equation gives us the ground state minimum energy of the system (lets say by DFT/HF/QMC whatever), this energy is a little higher than that.
My first question is, because I have learned that...
Dear,
I am reading a paper on Bose Einstein condensate and an atom laser. I have two questions which are bothering me for a time.
- When you are going to make do all the atoms start with the same the Broglie wavelenghts or do they start with different wavelenghts due to different...
I was just wondering what properties of bose einstein condensates allows them to slow/stop light so well.
cant find much on the internet about it, tho i am probably looking in the wrong places, so if anyone could give me links that would be useful
Thanks
Also, this isn't homework, I'm...
Homework Statement
First, let's derive the predictions for He-4 atoms at very low temps given the MB distr.
Homework Equations
The Attempt at a Solution
Given the MB distr., if the ground state of the system is assumed to be at zero energy, then the ratio of occupation numbers...
Hello
My name is Peter
I know that so far some couple of people manage to make a Bose -Einstein condensate from a metal and from hydrogen, I would like to ask your opinion about what do you believe will happen if not the full atom will be brought to the Bose Einstein condensate state or...
show that in the thermodynamic limit the bose gas condensate does not contribute to pressure for ideal bose gas in volume V with N particles.and physically explain.
how to get it start?and what will b its physicsl explanation?
kindly reply soooooooooooon
Hi i tried in the other section with no luck.
Let me try here if there are anyone here that can help me.
the question is:
Suppose one catches in 5000-Na atoms in a spherical-shaped cloud with diameter of 2mm.
And suppose that the atoms are uniformly distributed in that sphere.
At what...
goooooovy man
http://www.youtube.com/watch?v=QxbutNmaL-s&NR=1
addendum:
any body know any other soliton waves in nature that are this aeshetically impressive?
A few questions about BEC:
A) When these bosons condensate, many particles fill the ground state. I read from textbooks that this would imply that they occupy the same position.
-1- experiments are done with Rb atoms, which consist of protons, neutrons and electrons. Wouldn't the electrons...
If we cool down a small sample of atoms and see bose-einstein condensation,
and so the speed of the atoms is slowed down dramatically,
what can we say about the speed of the sub-atomic particles
(quarks etc..), do we know how their speed is being changed?
regards, marcel