Related topics: physical review letters

Researchers embrace imperfection to improve biomolecule transport

While watching the production of porous membranes used for DNA sorting and sequencing, University of Illinois researchers wondered how tiny steplike defects formed during fabrication could be used to improve molecule transport. ...

Atomically precise models improve understanding of fuel cells

Simulations from researchers in Japan provide new insights into the reactions occurring in solid-oxide fuel cells by using realistic atomic-scale models of the active site at the electrode based on microscope observations ...

The fun way to manipulate atoms

With their potential to perform calculations far beyond the reach of conventional supercomputers, machines harnessing certain quantum physics phenomena are expected to change the way the world solves complex problems. They ...

Organic porous structures on 2-D defect networks

NUS scientists have developed a method for self-assembly of hexagonal organic porous structures on molybdenum diselenide (MoSe2) film to create ordered nanostructures.

A study describes the reaction mechanism of DNAzymes

A study from the Institute for Research in Biomedicine (IRB Barcelona) has published a study in the journal Nature Catalysis that describes the reaction mechanism used by the DNAzyme 9DB1, the first structurally available ...

Scientists map toxic proteins linked to Alzheimer's

A team of researchers from McMaster University has mapped at atomic resolution a toxic protein linked to Alzheimer's disease, allowing them to better understand what is happening deep within the brain during the earliest ...

Neutrons get a wider angle on DNA and RNA to advance 3-D models

Scientists from the National Institute of Standards and Technology (NIST) and the University of Maryland are using neutrons at Oak Ridge National Laboratory (ORNL) to capture new information about DNA and RNA molecules and ...

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Perturbation theory (quantum mechanics)

In quantum mechanics, perturbation theory is a set of approximation schemes directly related to mathematical perturbation for describing a complicated quantum system in terms of a simpler one. The idea is to start with a simple system for which a mathematical solution is known, and add an additional "perturbing" Hamiltonian representing a weak disturbance to the system. If the disturbance is not too large, the various physical quantities associated with the perturbed system (e.g. its energy levels and eigenstates) can, from considerations of continuity, be expressed as 'corrections' to those of the simple system. These corrections, being 'small' compared to the size of the quantities themselves, can be calculated using approximate methods such as asymptotic series. We can therefore study the complicated system based on our knowledge of the simpler one.

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