Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Optical tweezers to prove Einstein right

31.01.2005


100 years after Einstein’s landmark paper, optical tweezer technology could confirm the theory of classical Brownian motion in details that Einstein missed when he first proposed it a century ago. This research is reported today in a special Einstein Year issue of the New Journal of Physics (www.njp.org) published jointly by the Institute of Physics and the German Physical Society (Deutsche Physikalische Gesellschaft).



“Optical tweezers” use a focused laser beam to trap and study microscopic objects, such as the individual bio-molecules that power muscle cells and propel sperm, and those that read the genetic code. The device is disturbed, however, by a subtle effect in Brownian motion known as the back-flow effect.

100 years ago in 1905, Einstein published a landmark paper on Brownian motion. He theorised that it is the constant buffeting of microscopic particles that goes on in any fluid as the fluid molecules randomly knock those particles around. He missed the subtle "back-flow effect" in which the very movement of a particle disturbs the water which ultimately bounces back to nudge the particle in return. "It’s like a boat that tries to stop, and then is pushed by its stern wave when that wave catches up with the boat," explains Henrik Flyvbjerg of Risø National Laboratory in Denmark. "Optical tweezers sense the back-flow effect," adds Flyvbjerg, "but that also means it can be studied with them."


Einstein described Brownian motion as arising from the "white" noise of random molecular motion due to heat. But, the back-flow effect makes higher frequencies slightly more likely, making the white noise "bluey white". Flyvbjerg and his colleagues demonstrate that optical tweezers technology is now at the point where this colour shift can be measured directly. He is collaborating with Stanford University’s Steve Block to push the technology to do it. If successful, they will confirm Brownian motion’s last unobserved trait, 100 years after Einstein’s initial theory for it.

David Reid | alfa
Further information:
http://www.iop.org
http://stacks.iop.org/1367-2630/7/i=1/a=E01

More articles from Physics and Astronomy:

nachricht Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory

nachricht SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>