General rules for bosonic bunching in multimode interferometers

We perform a comprehensive set of experiments that characterize bosonic bunching of up to 3 photons in interferometers of up to 16 modes. Our experiments verify two rules that govern bosonic bunching. The first rule, obtained recently in [1,2], predicts the average behavior of the bunching probability and is known as the bosonic birthday paradox. The second rule is new, and establishes a n!-factor quantum enhancement for the probability that all n bosons bunch in a single output mode, with respect to the case of distinguishable bosons. Besides its fundamental importance in phenomena such as Bose-Einstein condensation, bosonic bunching can be exploited in applications such as linear optical quantum computing and quantum-enhanced metrology.Comment: 6 pages, 4 figures, and supplementary material (4 pages, 1 figure

Fermonic anyons: entanglement and quantum computation from a resource-theoretic perspective

Often quantum computational models can be understood via the lens of resource theories, where a computational advantage is achieved by consuming specific forms of quantum resources and, conversely, resource-free computations are classically simulable. For example, circuits of nearest-neighbor matchgates can be mapped to free-fermion dynamics, which can be simulated classically. Supplementing these circuits with nonmatchgate operations or non-gaussian fermionic states, respectively, makes them quantum universal. Can we similarly identify quantum computational resources in the setting of more general quasi-particle statistics, such as that of fermionic anyons? In this work, we develop a resource-theoretic framework to define and investigate the separability of fermionic anyons. We build the notion of separability through a fractional Jordan-Wigner transformation, leading to a Schmidt decomposition for fermionic-anyon states. We show that this notion of fermionic-anyon separability, and the unitary operations that preserve it, can be mapped to the free resources of matchgate circuits. We also identify how entanglement between two qubits encoded in a dual-rail manner, as standard for matchgate circuits, corresponds to the notion of entanglement between fermionic anyons. Though this does not coincide with the usual definition of qubit entanglement, it provides new insight into the limited capabilities of matchgate circuits.Comment: 7+19 pages, 3 figure

Indirect tests of the Randall-Sundrum model

I present phenomenological implications of the Randall-Sundrum model for indirect searches, specifically a selection of flavor observables and Higgs-related collider searches. I review the interplay of constraints from CP violation in flavor physics, possible effects in rare decays, and model-specific protection mechanisms. Deviations in the Higgs couplings to fermions and, at one-loop, to gluons are unexpectedly strong and lead to strong modifications in Higgs searches.Comment: 8 pages, 6 figures; Talk given at Discrete '10: Symposium on Prospects in the Physics of Discrete Symmetries, Rome, Italy, 6-11 Dec 201

Ballpark Figures

On May 5, voters in Forsyth and Guilford counties will decide whether they want to foot two-thirds of the bill for a new baseball stadium. I haven’t yet decided how I’ll vote, but I’m leaning towards “no” for one reason: Supporters of the stadium are trying to sell it as something it ain’t

Eliminating Rental Tax Break Won’t Harm the Furniture Market

Recently the Clinton administration proposed eliminating a tax break that benefits some homeowners in the Triad. Currently, income from renting one’s home out for 15 days or less in a given year is not subject to federal income tax. Under the proposal, all rental income would be taxable

Invest in Bridges and Roads, not Rebates

After much political wrangling, Congress passed an economic stimulus package this month. No one knows for sure whether the increasingly sluggish U.S. economy will dip into recession in 2008 or just grow very slowly, but Congress isn’t waiting to find out. In the fourth quarter of 2007 the economy grew at an annualized rate of just 0.6 percent

Greenbucks in Greensboro? An Odd Idea With Some Merit

Buying local has long been a goal of those who pay attention to the environmental impact of their shopping decisions. During the Great Recession, the buy-local concept had been adopted by chambers of commerce hoping to reinvigorate sagging local economies by keeping more spending at home