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Are the recent IceCube events hinting at O(100) TeV decaying dark matter?

Atri Bhattacharya University of Liège
May 22, 2014

PIRSA:14050118
Particle Physics
Positive Energy in Quantum Gravity

Lee Smolin Perimeter Institute for Theoretical Physics

May 21, 2014

PIRSA:14050126
Asymptotic safety – a quantum theory of gravity and matter

Astrid Eichhorn Universität Heidelberg

May 21, 2014

PIRSA:14050125
Phases for (analogue) spin foam models

Sebastian Steinhaus Friedrich Schiller University Jena

May 21, 2014

PIRSA:14050124
TBA

Flavio Mercati University of Naples Federico II

May 21, 2014

PIRSA:14050123
Entanglement and Edge Modes in Gauge Theory and Gravity

May 21, 2014

PIRSA:14050122
TBA

Florian Girelli University of Waterloo

May 21, 2014

PIRSA:14050121
Gauge theory of gravity and matter

Steven Kerr ThinkTank Maths Ltd.

May 21, 2014

PIRSA:14050120
Equality

Tobias Fritz Universität Innsbruck

May 21, 2014

PIRSA:14050063
New Vacuum and Representation For Loop Quantum Gravity

Bianca Dittrich Perimeter Institute for Theoretical Physics

May 21, 2014

PIRSA:14050119
Designing exotic circuitry with non-Abelian anyons
May 20, 2014

PIRSA:14050029
Condensed Matter
Local quanta, unitary inequivalence, and vacuum entanglement

Hans Westman
May 20, 2014

PIRSA:14050117
Quantum Foundations

Are the recent IceCube events hinting at O(100) TeV decaying dark matter?

Atri Bhattacharya University of Liège
May 22, 2014

PIRSA:14050118
Particle Physics
The IceCube detector has recently reported the observation of 28 events at previously unexplored energies. While the statistics of the observed events are still low, these events hint at the existence of a neutrino flux over and above the atmospheric neutrino background. We investigate the possibility that a significant component of the additional neutrino flux originates due to the decay of a very heavy dark matter (VHDM) particle via several possible channels into standard model particles. We show that a combination of a power law astrophysical neutrino spectrum and the neutrino flux from the decay of a DM species of mass in the range 150-400 TeV improves the fit to the observed neutrino events than that obtained from a best-fit astrophysical flux alone. Assuming the existence of an astrophysical background described by the IC best-fit, we also show that, for the decay of even heavier DM particles ($m_{\text{DM}} \sim 1$ PeV), the same observations impose significant constraints on the decay lifetimes. Allowing the astrophysical flux normalization to vary leads to modifications of these limits; however, there is still a range of dark matter mass and lifetime that is excluded by the IC results.
Positive Energy in Quantum Gravity

Lee Smolin Perimeter Institute for Theoretical Physics

May 21, 2014

PIRSA:14050126
Asymptotic safety – a quantum theory of gravity and matter

Astrid Eichhorn Universität Heidelberg

May 21, 2014

PIRSA:14050125
Phases for (analogue) spin foam models

Sebastian Steinhaus Friedrich Schiller University Jena

May 21, 2014

PIRSA:14050124
TBA

Flavio Mercati University of Naples Federico II

May 21, 2014

PIRSA:14050123
Entanglement and Edge Modes in Gauge Theory and Gravity

May 21, 2014

PIRSA:14050122
TBA

Florian Girelli University of Waterloo

May 21, 2014

PIRSA:14050121
Gauge theory of gravity and matter

Steven Kerr ThinkTank Maths Ltd.

May 21, 2014

PIRSA:14050120
Equality

Tobias Fritz Universität Innsbruck

May 21, 2014

PIRSA:14050063

Equality of two mathematical objects is a seemingly simple and well-understood concept. In this talk, I will do three things to explain why this is a misconception: I will survey different notions of equality, explain how revising the notion of equality has led to an emerging alternative foundation of mathematics called "homotopy type theory", and try to convince you that thinking about equality is relevant to your research in quantum field theory, quantum gravity or quantum foundations.
New Vacuum and Representation For Loop Quantum Gravity

Bianca Dittrich Perimeter Institute for Theoretical Physics

May 21, 2014

PIRSA:14050119
Designing exotic circuitry with non-Abelian anyons
May 20, 2014

PIRSA:14050029
Condensed Matter
Non-Abelian anyons are widely sought for the exotic fundamental physics they harbor as well as for their possible applications for quantum information processing. Currently, there are numerous blueprints for stabilizing the simplest type of non-Abelian anyon, a Majorana zero energy mode bound to a vortex or a domain wall. One such candidate system, a so-called "Majorana wire" can be made by judiciously interfacing readily available materials; the experimental evidence for the viability of this approach is presently emerging.
Following this idea, we introduce a device fabricated from conventional fractional quantum Hall states, s-wave superconductors and insulators with strong spin-orbit coupling. Similarly to a Majorana wire, the ends of our “quantum wire” would bind "parafermions", exotic non-Abelian anyons which can be viewed as fractionalised Majorana zero modes.
I will discuss their properties and describe how such parafermions can be used to construct new and potentially useful circuit elements which include current and voltage mirrors, transistors for fractional charge currents and "flux capacitors".
Local quanta, unitary inequivalence, and vacuum entanglement

Hans Westman
May 20, 2014

PIRSA:14050117
Quantum Foundations
In this work we develop a formalism for describing localised quanta for a real-valued Klein-Gordon field in a one-dimensional box [0, R]. We quantise the field using non-stationary local modes which, at some arbitrarily chosen initial time, are completely localised within the left or the right side of the box. In this concrete set-up we directly face the problems inherent to a notion of local field excitations, usually thought of as elementary particles. Specifically, by computing the Bogoliubov coefficients relating local and standard (global) quantizations, we show that the local quantisation yields a Fock space F^L which is unitarily inequivalent to the standard one F^G. In spite of this, we find that the local creators and annihilators remain well defined in the global Fock space F^G, and so do the local number operators associated to the left and right partitions of the box. We end up with a useful mathematical toolbox to analyse and characterise local features of quantum states in F^G . Specifically, an analysis of the global vacuum state |0_G> ∈ F^G in terms of local number operators shows, as expected, the existence of entanglement between the left and right regions of the box. The local vacuum |0_L> ∈ F^L , on the contrary, has a very different character. It is neither cyclic nor separating and displays no entanglement. Further analysis shows that the global vacuum also exhibits a distribution of local excitations reminiscent, in some respects, of a thermal bath. We discuss how the mathematical tools developed herein may open new ways for the analysis of fundamental problems in local quantum field theory.

Title	Date	Collection	Type	Info
Are the recent IceCube events hinting at O(100) TeV decaying dark matter?	2014‑05‑22	Particle Physics	Scientific Series	View details
Positive Energy in Quantum Gravity	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
Asymptotic safety – a quantum theory of gravity and matter	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
Phases for (analogue) spin foam models	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
TBA	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
Entanglement and Edge Modes in Gauge Theory and Gravity	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
TBA	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
Gauge theory of gravity and matter	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
Equality	2014‑05‑21	Colloquium	Scientific Series	View details
New Vacuum and Representation For Loop Quantum Gravity	2014‑05‑21	Quantum Gravity Day 2014	Conference	View details
Designing exotic circuitry with non-Abelian anyons	2014‑05‑20	Quantum Matter	Scientific Series	View details
Local quanta, unitary inequivalence, and vacuum entanglement	2014‑05‑20	Quantum Foundations	Scientific Series	View details

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