Cell Swelling by Osmosis: a Variational Approach

A very simple model for cell swelling by osmosis is introduced, resulting in a parabolic free boundary problem. In case of radially symmetric initial conditions, it is shown that the model can be viewed as a gradient flow involving entropy, surface area and the Wasserstein metric. This observation is used to construct solutions and explain the presence and nature of osmosis

Spherical Fourier Transforms on Locally Compact Quantum Gelfand Pairs

We study Gelfand pairs for locally compact quantum groups. We give an operator algebraic interpretation and show that the quantum Plancherel transformation restricts to a spherical Plancherel transformation. As an example, we turn the quantum group analogue of the normaliser of SU(1,1) in $SL(2,\mathbb{C}$) together with its diagonal subgroup into a pair for which every irreducible corepresentation admits at most two vectors that are invariant with respect to the quantum subgroup. Using a $\mathbb{Z}_2$-grading, we obtain product formulae for little $q$-Jacobi functions

Top quark pair cross section measurement at ATLAS

An accurate determination of the top quark pair production cross section at the LHC provides a valuable check of the Standard Model. Given the high statistics which will be available (about one top quark pair per second, at a luminosity of 10^33 cm^-2 s^-1), this check can be performed relatively fast after the turn on of the LHC. The prospects for measuring the total top quark pair cross section with the ATLAS detector during the initial period of LHC running will be presented here. The cross section is determined in the single lepton channel and in the dilepton channel.Comment: ICHEP0

Instantaneous coherent destruction of tunneling and fast quantum state preparation for strongly pulsed spin qubits in diamond

Qubits driven by resonant strong pulses are studied and a parameter regime is explored in which the dynamics can be solved in closed form. Instantaneous coherent destruction of tunneling can be seen for longer pulses, whereas shorter pulses allow a fast preparation of the qubit state. Results are compared with recent experiments of pulsed nitrogen-vacancy center spin qubits in diamond.Comment: 9 pages, 4 figures. Published in the special issue of Chemical Physics in honor of Peter Hangg

The Incognito of a Thief: Johannes Climacus and the Poetics of Self-Incrimination

In this essay, I advance a reading of Philosophical Crumbs or a Crumb of Philosophy, published by Søren Kierkegaard under the pseudonym Johannes Climacus. I argue that this book is animated by a poetics of self-incrimination. Climacus keeps accusing himself of having stolen his words from someone else. In this way, he deliberately adopts the identity of a thief as an incognito. To understand this poetics of self-incrimination, I analyze the hypothetical thought-project that Climacus develops in an attempt to show what it means to go further than Socrates. In my reading, I distinguish between a Socratic and a non-Socratic conception of education, both of which rely on an incognito. Socrates takes on the maieutic incognito of an ignorant bystander in order to force his interlocutors to turn inward so that the truth that is already within them can be born. In contrast, the non-Socratic education that Climacus advances as a hypothesis relies on what I call ‘the incognito as a true form’. It is an incognito insofar as it confronts the pupils with a paradox on which the understanding runs aground. It is a true form insofar as its immediate appearance is not a disguise, but a true form. This indirect mode of communication is necessary, without it pupils will not be able to encounter a truth that is not inherent within them. Climacus’ poetics of self-incrimination, I argue, tries to repeat this indirect mode of communication by adopting the incognito of a thief as a true form