Nobel Prize In Physics For Bose-Einstein Condensate 201
LMCBoy writes "The Royal Swedish Academy of Sciences announced the 2001 Nobel Prize in Physics today. The award went to scientists who managed to construct a Bose-Einstein condensate from Rubidium and Sodium atoms. The process involves cooling the atoms to about 20 nanoKelvin. From the press release: 'A laser beam differs from the light from an ordinary light bulb in several ways. In the laser the light particles all have the same energy and oscillate together. To cause matter also to behave in this controlled way has long been a challenge for researchers. This year's Nobel Laureates have succeeded - they have caused atoms to "sing in unison" - thus discovering a new state of matter, the Bose-Einstein condensate.'" This is the same reasearch that Hemos recently posted about.
That Timothy! (Score:1, Informative)
Congratulations! (Score:4, Informative)
From the Physics department here at the University of Colorado, I consider myself lucky to work with folks like Dr. Weiman (one of the Nobel recipients) and others in the field, and congratulate all the Nobel winners for this year.
On that note, you can read all about Bose-Einstein Condensate and more at Physics 2000, our award-winning interactive journey through modern physics! The site is here:
http://www.colorado.edu/physics/2000
Our Bose-Einstein Condensate section is one of the most popular, check it out and learn more!
Ryan Bruels
Technical Consultant
Physics 2000
Center for Integrated Plasma Studies
University of Colorado, Boulder
Is this research into superconductors? (Score:1, Informative)
From Alfred Nobel's Will: (Score:3, Informative)
Re:Is this research into superconductors? (Score:2, Informative)
These are not masers! (Score:3, Informative)
Particles that can all have the same EXACT state, in quantum mechanical terms, are called bosons. They fill and occupy available states in a certain way, described by a Bose distribution. An example of bosons are photons, or light, which can all be in the same state at the same time, hence making the maser and laser possible. Opposite to these are fermions, e.g. electrons, which cannot occupy the same state and are subject to Fermi-Dirac statistics.
What makes B-E condensates cool, no pun intended, is through cooling and laser pumping all the atoms can be made to be in the exact state. This allows all kinds of neat things to happen. Such as the "matter laser" or the actual slowing down and stopping of light (I'm to lazy to look up the link but check out Scientific American's website).
Pretty neat stuff.
Re:Is this research into superconductors? (Score:4, Informative)
Huh? A superconductor by definition already conducts current perfectly. There's no "best" superconductor in that sense, they're all the same (perfect). What people are researching now is high-temperature superconductors, which this is most definitively not (at 20 millikelvin).
Masers have absolutely nothing to do with this (Score:3, Informative)
That said, it's possible that some reporter with absolutely no technical background abbreviated "matter laser" to "maser," but that would be a mistake since it causes immense confusion to anyone who remembers the original definition. If you meant "matter laser," then say so.
Re:But what does it *do*? (Score:4, Informative)
Those "safe securities" (Score:3, Informative)
"On November 27, 1895, a year before his death, Alfred Nobel signed the famous will which would implement some of the goals to which he had devoted so much of his life. Nobel stipulated in his will that most of his estate, more than SEK 31 million (today approximately SEK 1,500 million) should be converted into a fund and invested in "safe securities."
The income from the investments was to be "distributed annually in the form of prizes to those who during the preceding year have conferred the greatest benefit on mankind."
The Nobel Foundation is a private institution established in 1900 on the basis of the will. The investment policy of the Foundation is naturally of paramount importance to the preservation and, if possible the augmentation of the funds and, thus, of the prize amount. According to the original 1901 investment rules, the term "safe securities" was, in the spirit of that time, interpreted to mean gilt-edged bonds or loans backed by such securities or backed by mortgages on real estate. With the changes brought about by the two World Wars and their economic and financial aftermath, the term "safe securities" had to be reinterpreted in the light of prevailing economic conditions and tendencies. Thus, at the request of the Foundation's Board of Directors, in the early 1950s the Swedish Government sanctioned changes, whereby the Board for all practical purposes was given a free hand to invest not only in real estate, bonds and secured loans, but also in most types of stocks.
From 1901, when the first prizes (SEK 150,000 each) were awarded, the prize amounts declined steadily. But with this freedom to invest, along with the long-fought-for tax-exemption granted in 1946, it was possible to reverse this trend and, on average, even keep pace with increasing inflation. The real value of the prize amount in SEK terms was finally restored in 1991. The amount of the 2001 Nobel Prize is SEK 10.0 million, an increase of around 11 per cent compared to the 2000 Prizes.
The investment capital at market value as per December 31, 2000, amounted to SEK 3,894 million (approx. USD 409 million). Foreign and Swedish assets accounted for 52 and 48 per cent, respectively."
link... [nobel.se]
There's also a table there breaking down the investments in more detail, but it was too big a PITA to get it to post correctly.
Re:Okay... (Score:2, Informative)
As far as I know we have trasported a light photon. And, I think someone transported a bunch of 'something'? I can't remember, but it was a bunch of it.
I guess the only thing preventing us from moving big stuff really comes down to the equipment and being able to handle the massive amount of data that would be generated in a 'timely' fashion.
Re:proves decades old theory (Score:2, Informative)
Re:Most interesting property of BECs (Score:5, Informative)
Bzzt. At near absolute zero you approach what is called "zero-point motion". Quantum mechanical oscillators still vibrate at their lowest energy level (their energy being (1/2)*h*(frequency)). So even at absolute zero you don't have electrons flying all over the place. (Actually, room temperature is virtually absolute zero on an electronic basis anyway -- most electronic excited states are effectively in the thousands of kelvin).
Re:I'm confused... (Score:2, Informative)
No, the Nobel Prize in Physics goes to whoever makes the greatest contribution to... physics! Someone who developed a key procedure to eliminate the plague of AIDS would be likely to win the Nobel Prize for Medicine though.
Re:These are not masers! (Score:2, Informative)
Um, no. Bosons are (by definition) particles with integer spin (0, +1, -1, etc.).
Umm, no. Photons, because the have no mass, are completely unable to form a Bose-Einstein condensate. In a laser, the photons are emitted with coherent phase. This is not at all the same as being in the same quantum-mechanical state.
-JS
Re:Okay... (Score:3, Informative)
>big stuff really comes down to the equipment and
>being able to handle the massive amount of data
>that would be generated in a 'timely' fashion.
Those are two major problems; there are plenty of others. There is a *huge* difference in "transporting" single photons and transporting larger objects. A photon has essentially two possible states (the helicity; left-handed or right-handed). Let's suppose all we needed was such spin information from every particle in a person's body in order to transport them. Try figuring out how many megabytes of information that is: we have 2^N possible values, where N is the number of particles. Divide by 2^23 to convert to megabytes. 23 is a lot smaller than N, so we may as well say it's still 2^N. N is really, really big. And now we consider that we need to get a lot more information right. Like the relative positions and velocities of the particles. We wouldn't want to transport someone and find his hand is flying away from him, would we? And how are we to extract this kind of information in the first place? Sure, entanglement is nice for say 5 particles, and for dealing with simple quantum states. It doesn't do you much good for much larger numbers of particles; and you generally have to have things beginning in the same place to entangle them.
I'm no expert in this particular area, but I think I understand basic quantum mechanics well enough to tell you that transporters are, almost certainly, never going to happen.
Some Basic Info about Bose-Einstein Condensates (Score:4, Informative)
Satyendranath Bose was a Indian Physicist.
Bosons (named after him) are particles that can be in the same quantum state.
The consequence of that is they can be in the same location.
While Fermions (such as electrons) cannot be in the same location (unless they are in Cooper pairs, which is how superconductors work, but I digress).
This is why electrons must exist in ever increasing shells around an atom -- they can never be in the same "location".
Einstein's contribution (at least I think this was his contribution), is to propose the following:
As well all know
To explain: If a particle is at location 'x', think of a Gaussian function centered at 'x', where the height of the function determines the probability that the particle is at that location.
A particle that is very well localized is traveling very fast, and vise versa.
And as the particle slows, the particle is less well localized, and it's wave function (that Gaussian) widens.
As Bosons (of the same type, say Rubidium atoms) cool, they slow down.
As they slow down, their wave functions expand.
At some point, their wave functions will overlap.
Now here is the cool bit. The atoms are in different quantum states and different internal energy levels to start with, but as soon as their wave functions overlap enough, they ALL immediately drop down to their ground state (which is the same for all of them), and you can no longer distinguish which atom is which!
The analogy would be to imagine an orchestra.
They are all tuning their instruments, but because they are all moving very fast, they cannot hear each other, and all the instruments are (or can be) in a slightly different tune.
When they all slow down (in the same room), they can hear each other, and suddenly they all become in tune with each other.
Not a very good analogy, I know.
Oh! I almost forgot. To cool the sample down to 20 nanoKelvin(?), this is what they do:
Of course once the condensate forms you can't measure it, b/c as soon as you try the damn thing evaporates!
So you have to observe it using other means....