7629
2014
2014
eng
15811
15817
7
16
30
article
The Royal Society of Chemistry
Cambridge
1
--
2014-06-18
--
Scaled Brownian motion: a paradoxical process with a time dependent diffusivity for the description of anomalous diffusion
Anomalous diffusion is frequently described by scaled Brownian motion (SBM){,} a Gaussian process with a power-law time dependent diffusion coefficient. Its mean squared displacement is ?x2(t)? [similar{,} equals] 2K(t)t with K(t) [similar{,} equals] t[small alpha]-1 for 0 < [small alpha] < 2. SBM may provide a seemingly adequate description in the case of unbounded diffusion{,} for which its probability density function coincides with that of fractional Brownian motion. Here we show that free SBM is weakly non-ergodic but does not exhibit a significant amplitude scatter of the time averaged mean squared displacement. More severely{,} we demonstrate that under confinement{,} the dynamics encoded by SBM is fundamentally different from both fractional Brownian motion and continuous time random walks. SBM is highly non-stationary and cannot provide a physical description for particles in a thermalised stationary system. Our findings have direct impact on the modelling of single particle tracking experiments{,} in particular{,} under confinement inside cellular compartments or when optical tweezers tracking methods are used.
Physical chemistry, chemical physics : PCCP
10.1039/C4CP02019G
online registration
Au-006424
<a href="http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-76302">Zweitveröffentlichung in der Schriftenreihe Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe ; 180 </a>
Jae-Hyung Jeon
Aleksei V. Chechkin
Ralf Metzler
eng
uncontrolled
single-particle tracking
eng
uncontrolled
living cells
eng
uncontrolled
random-walks
eng
uncontrolled
subdiffusion
eng
uncontrolled
dynamics
eng
uncontrolled
nonergodicity
eng
uncontrolled
coefficients
eng
uncontrolled
transport
eng
uncontrolled
membrane
eng
uncontrolled
behavior
Physik
Institut für Physik und Astronomie
Referiert
Open Access
RSC
7630
2014
2014
eng
15811
15817
postprint
1
2015-04-30
2014-06-18
--
Scaled Brownian motion: a paradoxical process with a time dependent diffusivity for the description of anomalous diffusion
Anomalous diffusion is frequently described by scaled Brownian motion (SBM){,} a Gaussian process with a power-law time dependent diffusion coefficient. Its mean squared displacement is ?x2(t)? [similar{,} equals] 2K(t)t with K(t) [similar{,} equals] t[small alpha]-1 for 0 < [small alpha] < 2. SBM may provide a seemingly adequate description in the case of unbounded diffusion{,} for which its probability density function coincides with that of fractional Brownian motion. Here we show that free SBM is weakly non-ergodic but does not exhibit a significant amplitude scatter of the time averaged mean squared displacement. More severely{,} we demonstrate that under confinement{,} the dynamics encoded by SBM is fundamentally different from both fractional Brownian motion and continuous time random walks. SBM is highly non-stationary and cannot provide a physical description for particles in a thermalised stationary system. Our findings have direct impact on the modelling of single particle tracking experiments{,} in particular{,} under confinement inside cellular compartments or when optical tweezers tracking methods are used.
urn:nbn:de:kobv:517-opus4-76302
online registration
Au-006424
Phys. Chem. Chem. Phys., 2014, 16, 15811 -15817 - DOI: 10.1039/C4CP02019G
<a href="http://publishup.uni-potsdam.de/opus4-ubp/frontdoor/index/index/docId/7629">Bibliographieeintrag der Originalveröffentlichung/Quelle</a>
Jae-Hyung Jeon
Aleksei V. Chechkin
Ralf Metzler
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
180
eng
uncontrolled
single-particle tracking
eng
uncontrolled
living cells
eng
uncontrolled
random-walks
eng
uncontrolled
subdiffusion
eng
uncontrolled
dynamics
eng
uncontrolled
nonergodicity
eng
uncontrolled
coefficients
eng
uncontrolled
transport
eng
uncontrolled
membrane
eng
uncontrolled
behavior
Physik
open_access
Institut für Physik und Astronomie
Referiert
Open Access
Universität Potsdam
https://publishup.uni-potsdam.de/files/7630/pmnr180.pdf