Bose Einstein condensate can be made to attract

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Discussion Overview

The discussion revolves around the properties and behaviors of Bose-Einstein condensates (BECs), particularly focusing on the ability of atoms within a BEC to attract or repel each other, as demonstrated by research from Carl Wieman's team at NIST. Participants explore the implications of this phenomenon, including the mechanisms behind it and the specific conditions under which these interactions occur.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Meta-discussion

Main Points Raised

  • Some participants express fascination with the phenomenon of BECs and seek insights into the underlying mechanisms.
  • It is noted that Wieman's team has created a self-attracting BEC that exhibited a contraction followed by an explosion, referred to as a "Bosenova."
  • Questions arise regarding the source of the forces that cause attraction and repulsion among atoms in a BEC.
  • Participants discuss the role of Feshbach resonance in altering atomic interactions and its potential connection to the observed explosions in BECs.
  • There is curiosity about the choice of Rubidium-85 for these experiments and the implications of using elements with specific atomic properties for creating BECs.
  • Some participants mention the difficulty in finding updated information on the topic and express a desire for more recent research papers or explanations.
  • Concerns are raised about the accessibility of past discussions and the challenge of keeping up with ongoing developments in the field.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the specifics of the mechanisms at play in BECs or the implications of the findings. Multiple competing views and questions remain unresolved throughout the discussion.

Contextual Notes

Participants highlight limitations in their understanding of complex concepts like Feshbach resonance and the specific conditions required for creating BECs, indicating a need for further clarification and exploration of these topics.

Who May Find This Useful

Readers interested in advanced topics in quantum physics, particularly those related to Bose-Einstein condensates, atomic interactions, and recent experimental findings in the field.

wolram
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this subject,amoung others facinate me, does anyone have an insight as to
what is happening here?
 
Last edited by a moderator:
Physics news on Phys.org


What is it ?
 
CARL WIEMAN and co at NIST have discovered that atoms inside
a bose einstein condensate can be made to attract or repel one another
they made a self attracting BEC, it began to shrink but then exploded.
sorry but url does not work but a google search for BOSENOVA does
cheers...
 
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Cool ! :smile:
Any idea as to the source of this force ?
 
i can find no more info on the web, maybe someone has read an upto date paper, i hate being left in suspence.
 
Originally posted by wolram
i can find no more info on the web, maybe someone has read an upto date paper, i hate being left in suspence.

You probably were reading this news release from NIST

http://www.colorado.edu/NewsServices/NewsReleases/2001/1104.html

I am posting the link to save people trouble of a google search and because I think the news release is pretty detailed and informative. Can anyone explain how by adjusting the magnetic field surrounding the condensate they can change the interaction between the atoms from one of attraction to repulsion and vice versa?

Has anyone an idea why they used Rubidium-85?

This press release has a link to a movie (it says) of
a rubidium bose-einstein condensate ball initially contracting
and then exploding

(analogy with Type II supernova was pointed out)

the temperature of 3 billionths of a kelvin is impressive---
apparently a record low

Carl Wieman's team is said to have announced this at an AIP conference and submitted this paper to Physical Review Letters:

Controlled Collapse of a Bose-Einstein Condensate," J. L. Roberts, N. R. Claussen, S. L. Cornish, E. A. Donley, E. A. Cornell, C. E. Wieman
 
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so far i have found that BECs have been made with
Rb,Na,Li,K,H and metastable He
im still looking for more info on related BOSENOVA
 
i found this exelent discription as to what is happening
sorry i cannot get the link to work, i did a google search for
feshbach resonance and came up with,
chapter 2 the 155 G Rb feshbach resonance 2.1 introduction 2.2
i do not understand all of it but perchance someone with more than my basic ganglion could give a simplified overview.[?]
 
Originally posted by wolram
i found this exelent discription as to what is happening
sorry i cannot get the link to work, i did a google search for
feshbach resonance and came up with,
chapter 2 the 155 G Rb feshbach resonance 2.1 introduction 2.2
i do not understand all of it but perchance someone with more than my basic ganglion could give a simplified overview.[?]

Another time you might try copying and pasting the URL
of whatever webpage it is
You could paste the ww... address right into the post
for us to copy. It does not need to form a workable link.
Just knowing the URL would suffice, making the google search unnecessary.
What does "feshbach resonance" look like in practical terms----might it be causing the observed explosions in BEC?
The name makes me think of trout fishing----bach means "creek" and the original name Fisch-bach doubtless meant "Fish-creek".
Today is sunday and the weather being fine one's mind naturally turns to more serious matters than physics.
 
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  • #10
I read somewhere that BECs can only be created from
ellements having an even number, or was it full shells,
I forgot.
Guess someone's goin'na have to do a serious search of
recent related info and post the links...
 
  • #11
This is over 2 yrs old, things have moved on a bit since then, and we covered this on the old forum? is there not acess to these postings? or has the database been collapsed?
 
  • #12
then relax and go fishing marcus, information may be years old to some of you but how are the multitude to know
that is the major problem with the internet unless you are at the forfront of these "DISCOVERIES" how is one suposed to know, i do beg your pardon about url but i didnt grow up with computers if somthing dosent seem to work i don't use it, i could say more but i think its time to call it a day and say goodby to this source of misinformation
your thankfully wolram.
 
  • #13
Originally posted by ranyart
This is over 2 yrs old, things have moved on a bit since then, and we covered this on the old forum? is there not acess to these postings? or has the database been collapsed?
I got the archive CD, but most others don't. Besides, like
you said, things have moved on a bit even since the
old forum. :wink: So why not discuss this all over again ! :smile:
 

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