Conference

Displaying 3037 - 3048 of 4979

Spin-1/2 Heisenberg Antiferromagnet on the Kagome Lattice: a Z2 Spin Liquid with Fermionic Spinons

Zhihao Hao University of Waterloo
April 25, 2013

PIRSA:13040134
Condensed Matter
Reaching Experimentally Quantum Criticality: A Playground to Explore Novel Correlated Quantum States of Matter

Radu Coldea University of Oxford
April 25, 2013

PIRSA:13040133
Condensed Matter
This is What a Scientist Looks Like
- Sampa Bhadra York University
- Natalia Toro Stanford University
- Shohini Ghose Wilfrid Laurier University
March 08, 2013

PIRSA:13030086
The Effects of Limited Resources and Opportunities on Women’s Careers in Physics: Results from the Global Survey of Physicists

Rachel Ivie American Institute of Physics

March 08, 2013

PIRSA:13030082
Making Physics Work: A Glimpse Behind the Scenes/Science
- Rachel Ivie American Institute of Physics
- John Berlinsky McMaster University
March 08, 2013

PIRSA:13030083
Creating Great Scientific Workplaces for Men and Women: From Practice to Theory and Back Again

Carla Fehr University of Waterloo

March 08, 2013

PIRSA:13030085
Q&A

Adriana Ocampo National Aeronautics and Space Administration

March 08, 2013

PIRSA:13030084
Closing Summary Talks
- Peter Loch University of Arizona
- Michael Spannowsky Durham University
- Brian Shuve Harvey Mudd College
February 23, 2013

PIRSA:13020145
boosted top: lessons learnt

Marcel Vos University of Valencia
February 21, 2013

PIRSA:13020141
Particle Physics
Jet substructure in BSM physics

Jay Wacker Quora Inc.
February 21, 2013

PIRSA:13020143
Particle Physics
Effective field theory framework in QG
- Xavier Calmet University of Sussex
- Roberto Percacci SISSA International School for Advanced Studies
- Astrid Eichhorn Universität Heidelberg
- Martin Reuter Johannes Gutenberg University Mainz
October 25, 2012

PIRSA:12100121
Quantum Gravity
Experimental tests of CPT symmetry

Antonio Di Domenico Sapienza University of Rome

October 25, 2012

PIRSA:12100120

Spin-1/2 Heisenberg Antiferromagnet on the Kagome Lattice: a Z2 Spin Liquid with Fermionic Spinons

Zhihao Hao University of Waterloo
April 25, 2013

PIRSA:13040134
Condensed Matter
Motivated by recent numerical and experimental studies of the spin-1/2 Heisenberg antiferromagnet on kagome, we formulate a many-body model for fermionic spinons, which are just uncoupled spins. The spinons interact with an emergent U(1) gauge field and experience strong short-range attraction in the S=0 channel. The ground state of the model is generically a Z(2) liquid. We calculate the edge of the two-spinon continuum and compare the theory to the slave-fermion approach to the Heisenberg model.
Reaching Experimentally Quantum Criticality: A Playground to Explore Novel Correlated Quantum States of Matter

Radu Coldea University of Oxford
April 25, 2013

PIRSA:13040133
Condensed Matter
Realizing experimentally continuous phase transitions in the electronic ground state of materials near zero temperature as a function of tuning some external parameter (magnetic field, pressure etc.) offers a unique opportunity to probe the extreme regime (near the transition point) where strong quantum correlations encompass the macroscopic sample as a whole, so called “quantum criticality” [1]. In this regime of strong correlations small perturbations/interactions can stabilize novel forms order or collective fluctuations that otherwise do not exist. One of the theoretically most studied paradigms for quantum criticality is a chain of Ising spins driven by a transverse field to a critical point separating spontaneous magnetic order and paramagnetic phases. We have realized this system experimentally by applying strong magnetic fields to the quasi-one-dimensional Ising ferromagnet CoNb2O6 and have probed via single-crystal inelastic neutron scattering the evolution of the magnetic order and spin excitation spectrum as a function of applied field at mili-Kelvin temperatures [2]. Near the critical point the spin excitations were theoretically predicted nearly two decades ago to have a set of quantum resonances (collective modes of vibration of the interacting spins) with universal ratios between their frequencies reflecting an exceptional mathematical structure of the quantum many-body eigenstates with a “hidden” E8 symmetry governing the physics in the scaling limit. Experiments indeed observed evidence for a spectrum of resonances and the ratio between the frequencies of the two lowest modes approached the "golden ratio" near the critical point, as predicted by field theory. As a second example of novel physics near quantum criticality I will discuss how an amplitude-modulated incommensurate spin-density wave (SDW) order appears near the field-induced critical point in the quasi-1D spin-1/2 XY antiferromagnet Cs2CoCl4. Incommensurate SDWs are very uncommon in magnetic insulators and are not stable zero-temperature ground states at the classical mean-field level, we propose that here such a state is stabilized by the strong quantum fluctuations associated with the proximity to the critical point and the weak frustrated inter-chain couplings.
This is What a Scientist Looks Like
- Sampa Bhadra York University
- Natalia Toro Stanford University
- Shohini Ghose Wilfrid Laurier University
March 08, 2013

PIRSA:13030086
The Effects of Limited Resources and Opportunities on Women’s Careers in Physics: Results from the Global Survey of Physicists

Rachel Ivie American Institute of Physics

March 08, 2013

PIRSA:13030082

The results of the Global Survey of Physicists draw attention to the need to focus on factors other than representation when discussing the situation of women in physics. Previous studies of women in physics have mostly focused on the lack of women in the field. This study goes beyond the obvious shortage of women and shows that there are much deeper issues. For the first time, a multinational study was conducted with 15000 respondents from 130 countries, showing that problems for women in physics transcend national borders. Across all countries, women have fewer resources and opportunities and are more affected by cultural expectations concerning child care. We show that limited resources and opportunities hurt career progress, and because women have fewer opportunities and resources, their careers progress more slowly. We also show the disproportionate effects of children on women physicists' careers. Cultural expectations about home and family are difficult to change. However, for women to have successful outcomes and advance in physics, they must have equal access to resources and opportunities. An article based on these findings can be found at: http://www.physicstoday.org/resource/1/phtoad/v65/i2/p47_s1
Making Physics Work: A Glimpse Behind the Scenes/Science
- Rachel Ivie American Institute of Physics
- John Berlinsky McMaster University
March 08, 2013

PIRSA:13030083
Creating Great Scientific Workplaces for Men and Women: From Practice to Theory and Back Again

Carla Fehr University of Waterloo

March 08, 2013

PIRSA:13030085

In this presentation Dr Fehr will discuss the results of ISU ADVANCE, a $3.3 million National Science Foundation supported research project designed to test strategies for improving the recruitment, retention, and advancement of women and members of underrepresented minority groups in science, technology, engineering and mathematics. In particular, this talk will address barriers to, and strategies for, improving the work climate in scientific communities. These improvements benefit both men and women scientists and support research excellence.
Q&A

Adriana Ocampo National Aeronautics and Space Administration

March 08, 2013

PIRSA:13030084
Closing Summary Talks
- Peter Loch University of Arizona
- Michael Spannowsky Durham University
- Brian Shuve Harvey Mudd College
February 23, 2013

PIRSA:13020145
boosted top: lessons learnt

Marcel Vos University of Valencia
February 21, 2013

PIRSA:13020141
Particle Physics
I briefly summarize the potential of the LHC to produce boosted objects and that of the experiments to recognize them as such analyzing jet substructure. Then, I consider boosted top quarks in some detail, the boosted object that has probably been most extensively studied. I evaluate ATLAS ttbar resonance searches to understand how and why dedicated algorithms outperform more classical techniques. Finally, I discuss a number of analyses where boosted techniques are likely to make a difference
Jet substructure in BSM physics

Jay Wacker Quora Inc.
February 21, 2013

PIRSA:13020143
Particle Physics
Effective field theory framework in QG
- Xavier Calmet University of Sussex
- Roberto Percacci SISSA International School for Advanced Studies
- Astrid Eichhorn Universität Heidelberg
- Martin Reuter Johannes Gutenberg University Mainz
October 25, 2012

PIRSA:12100121
Quantum Gravity
Gravity Induced Grand Unification
Motivated by the lack of evidence for physics beyond the Standard Model in the TeV region, we discussed an alternative path for grand unification. We show that simple grand unification models based on e.g. SU(5) can work successfully even without low scale supersymmetry. In particular quantum gravitational effects could easily modify the unification conditions for the gauge and Yukawa couplings.
_____________________________

Testing the consistency of quantum gravity with low-energy properties of the standard model
Testing quantum gravity is possible by using, e.g. the available data on the properties of the standard model. I will discuss how a parameterisation of quantum gravity fluctuations in terms of metric fluctuations can be used to test the compatibility of quantum gravity with the observed low-energy properties of the standard model, such as the existence of fermions with masses much below the Planck mass.
______________________________

The Asymptotic Safety program
The effective average action approach to Quantum Einstein Gravity (QEG) is discussed as a natural framework for exploring the scale dependent Riemannian geometry and multifractal micro-structure of the effective spacetimes predicted by QEG. Their fractal properties are related to the functional RG flow on theory space, and the special role of the running cosmological constant is emphasized. The prospects of an experimental verification will also be discussed.
Experimental tests of CPT symmetry

Antonio Di Domenico Sapienza University of Rome

October 25, 2012

PIRSA:12100120

The three discrete symmetries of Quantum Mechanics, charge conjugation, parity, and time reversal, are all violated, singly or in pairs. CPT is the only combination of these symmetries which appears to be conserved in Nature. Even though this result is in agreement with the well known CPT theorem, that holds for standard quantum field theories, CPT violation in some cases might be expected and justified in the framework of a quantum theory of gravity. Here the last and more refined experimental searches for CPT violation effects will be reported with a special focus on the tests performed on neutral meson systems and the interplay between CPT symmetry and the basic principles of Quantum Mechanics. No deviation from the expectations of CPT symmetry and quantum mechanics is observed, while the precision of the measurements, in some cases, reaches the interesting Planck scale region. Finally, prospects for this kind of experimental studies will be presented.

Title	Speaker(s)	Date	Talk Type	Info link
Spin-1/2 Heisenberg Antiferromagnet on the Kagome Lattice: a Z2 Spin Liquid with Fermionic Spinons	Zhihao Hao	2013-04-25	Conference	View details
Reaching Experimentally Quantum Criticality: A Playground to Explore Novel Correlated Quantum States of Matter	Radu Coldea	2013-04-25	Conference	View details
This is What a Scientist Looks Like	Sampa Bhadra, Natalia Toro, Shohini Ghose	2013-03-08	Conference	View details
The Effects of Limited Resources and Opportunities on Women’s Careers in Physics: Results from the Global Survey of Physicists	Rachel Ivie	2013-03-08	Conference	View details
Making Physics Work: A Glimpse Behind the Scenes/Science	Rachel Ivie, John Berlinsky	2013-03-08	Conference	View details
Creating Great Scientific Workplaces for Men and Women: From Practice to Theory and Back Again	Carla Fehr	2013-03-08	Conference	View details
Q&A	Adriana Ocampo	2013-03-08	Conference	View details
Closing Summary Talks	Peter Loch, Michael Spannowsky, Brian Shuve	2013-02-23	Conference	View details
boosted top: lessons learnt	Marcel Vos	2013-02-21	Conference	View details
Jet substructure in BSM physics	Jay Wacker	2013-02-21	Conference	View details
Effective field theory framework in QG	Xavier Calmet, Roberto Percacci, Astrid Eichhorn, Martin Reuter	2012-10-25	Conference	View details
Experimental tests of CPT symmetry	Antonio Di Domenico	2012-10-25	Conference	View details

Format results