Related topics: physical review letters

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 ...

Old ice and snow yields tracer of preindustrial ozone

Using rare oxygen molecules trapped in air bubbles in old ice and snow, U.S. and French scientists have answered a long-standing question: How much have "bad" ozone levels increased since the start of the Industrial Revolution?

Scientists offer designer 'big atoms' on demand

In the not-so-distant future, researchers may be able to build atoms to your specifications with the click of a button. It's still the stuff of science fiction, but a team at the University of Colorado Boulder reports that ...

The geometry of an electron determined for the first time

Physicists at the University of Basel have shown for the first time how a single electron looks in an artificial atom. A newly developed method enables them to show the probability of an electron being present in a space. ...

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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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