Search Talks

9313 - 9324 of 16860 Results

Frequency comparison of cryogenic optical lattice clocks

Hidetoshi Katori University of Tokyo

June 16, 2014

PIRSA:14060010
Zen and the art of atomic time-keeping (Tutorial on atomic clocks for particle theorists)

Andrei Derevianko University of Nevada Reno

June 16, 2014

PIRSA:14060009
Atomic Clocks and Tests of Fundamental Physics

Ekkehard Peik Physikalisch-Technische Bundesanstalt (PTB)

June 16, 2014

PIRSA:14060008
Introduction, Scope and goals of the workshop, Open questions in the field
- Asimina Arvanitaki Perimeter Institute for Theoretical Physics
- Derek Jackson Kimball California State University, East Bay
- Maxim Pospelov University of Minnesota
- Dmitry Budker University of California, Berkeley
June 16, 2014

PIRSA:14050149
Welcome

June 16, 2014

PIRSA:14060007
What Can We Learn from Precision Higgs

Maxim Perelstein Cornell University
June 13, 2014

PIRSA:14060003
Particle Physics
Inflation, Variable Speed of Light and BICEP2

John Moffat Perimeter Institute for Theoretical Physics
June 12, 2014

PIRSA:14060044
Cosmology
Sequential growth dynamics and quantum random walks

David Meyer University of California, San Diego
June 11, 2014

PIRSA:14060042
Mathematical physics
Wild and tame scalar-tensor black holes

Valerio Faraoni Bishop's University
June 10, 2014

PIRSA:14060043
Cosmology
Neutrino Wakes

Ue-Li Pen Canadian Institute for Theoretical Astrophysics (CITA)
June 06, 2014

PIRSA:14060041
Cosmology
Quantum technologies as tools to deepen our understanding of quantum theory and relativity

Ivette Fuentes University of Southampton
June 05, 2014

PIRSA:14060006
Quantum Information
From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg

S. James Gates Jr. University of Maryland, College Park

June 04, 2014

PIRSA:14060048

Frequency comparison of cryogenic optical lattice clocks

Hidetoshi Katori University of Tokyo

June 16, 2014

PIRSA:14060010

We report frequency comparison of two Sr optical lattice clocks operated at cryogenic temperature to dramatically reduce blackbody radiation shift. After 11 measurements performed over a month, the two cryo-clocks agree to within (-1.1±1.6)×〖10〗^(-18).
Current status of a frequency ratio measurement of Hg/Sr clocks and a remote comparison of cryo-clocks located at Riken and University of Tokyo will be mentioned.
Zen and the art of atomic time-keeping (Tutorial on atomic clocks for particle theorists)

Andrei Derevianko University of Nevada Reno

June 16, 2014

PIRSA:14060009
Atomic Clocks and Tests of Fundamental Physics

Ekkehard Peik Physikalisch-Technische Bundesanstalt (PTB)

June 16, 2014

PIRSA:14060008

The precision of atomic clocks continues to improve at a rapid pace: While caesium clocks now reach relative systematic uncertainties of a few 10-16, several optical clocks based on different atomic systems are now reported with uncertainties in the 10-18 range. This variety of precise clocks will allow for improved tests of fundamental physics, especially quantitative tests of relativity and searches for variations of constants. Laser-cooled and trapped ions permit the study of strongly forbidden transitions with extremely small natural linewidths and long coherence times. The frequency of the electric octupole transition S1/2 - F7/2 at 467 nm in 171Yb+ with a natural linewidth in the nHz range is remarkably insensitive against external electric and magnetic fields. We evaluate the systematic uncertainty of a frequency standard that is based on this transition as 4*10-18 at present. An even better isolation from external perturbations can be expected for the nuclear transition in 229Th3+ at about 160 nm with an expected linewidth in the mHz range. In order to excite the so far only indirectly observed nuclear transition using electronic bridge processes, we investigate the dense electronic level structure of Th+. Both transitions, in Yb+ and 229Th, are predicted to be highly sensitive to changes in the fine structure constant. I will give an update on limits on variations of constants as obtained from atomic clock comparisons.
Introduction, Scope and goals of the workshop, Open questions in the field
- Asimina Arvanitaki Perimeter Institute for Theoretical Physics
- Derek Jackson Kimball California State University, East Bay
- Maxim Pospelov University of Minnesota
- Dmitry Budker University of California, Berkeley
June 16, 2014

PIRSA:14050149
Welcome

June 16, 2014

PIRSA:14060007
What Can We Learn from Precision Higgs

Maxim Perelstein Cornell University
June 13, 2014

PIRSA:14060003
Particle Physics
In the coming years, LHC experiments will measure Higgs properties, such as its couplings, with increasing precision. Electron-positron Higgs factories, such as the ILC or TLEP, would be able to achieve even better precision. In this talk, I will discuss some of the physics questions that can be addressed by a precision Higgs coupling measurement program. First, the issue of naturalness of the electroweak scale can be addressed in a robust, model-independent manner. Second, the possibility of a first-order electroweak phase transition can be definitively probed, testing one of the necessary conditions of electroweak baryogenesis scenario.
Inflation, Variable Speed of Light and BICEP2

John Moffat Perimeter Institute for Theoretical Physics
June 12, 2014

PIRSA:14060044
Cosmology
A variable speed of light (VSL) cosmology is developed with a spontaneous breaking of Lorentz invariance in the early universe. A non-minimal electromagnetic coupling to curvature and the resulting quantum electrodynamic vacuum polarization dispersive medium can produce c >> c0 in the early universe, where c0 is the measured speed of light today. Higher derivative curvature contributions to the effective gravitational action and quantum gravity vacuum polarization can produce a dispersive medium and a large increase in the speed of gravitational waves cg >> cg0 in the early universe, where cg0 is the speed of gravitational waves today. The initial value problems of cosmology are solved: the horizon and flatness problems. The model predicts primordial scalar and tensor fluctuation spectral indices ns=0.96 and nt=- 0.04, respectively. The BICEP2 observation of r=0.2 yields r/nt=-5 which is close to the single-field inflationary consistency condition r/nt=-8.
Sequential growth dynamics and quantum random walks

David Meyer University of California, San Diego
June 11, 2014

PIRSA:14060042
Mathematical physics
Rideout and Sorkin proposed a classical dynamics for causal sets based upon a sequential growth model. Comparing it with models for sequential growth in other systems, and with the dual goals of generating manifold-like causal sets and finding a quantum dynamics for them, we propose some modifications to their model. The resulting, admittedly speculative, proposal is a type of quantum random walk. We explore its properties in some simple cases.
Wild and tame scalar-tensor black holes

Valerio Faraoni Bishop's University
June 10, 2014

PIRSA:14060043
Cosmology
In scalar-tensor gravity, black holes do not obey the Jebsen-Birkhoff theorem. Non-isolated black holes can be highly dynamical and the teleological concept of event horizon is replaced by the apparent or trapping horizon. Dynamical solutions describing inhomogeneities embedded in cosmological "backgrounds" and the phenomenology of their apparent horizons, which often appear/vanish in pairs, will be described. Isolated black holes, in contrast, have no hair and are the same as in general relativity.
Neutrino Wakes

Ue-Li Pen Canadian Institute for Theoretical Astrophysics (CITA)
June 06, 2014

PIRSA:14060041
Cosmology
We identify a new non-linear neutrino wake effect, due to the streaming motions of neutrinos relative to dark matter, analogous to the Tseliakhovich-Hirata effect. We compute the effect in moving background perturbation theory, compare to direct n-body simulations, and forecast its observability in current and future surveys. Depending on neutrino mass, this effect could be observable in upcoming surveys through a cross correlation dipole in lensing and galaxies. Unlike previous cosmological neutrino effects, this depends primarily on neutrino mass, making it complementary to measurements that depend on neutrino density.
Quantum technologies as tools to deepen our understanding of quantum theory and relativity

Ivette Fuentes University of Southampton
June 05, 2014

PIRSA:14060006
Quantum Information
Quantum information and quantum metrology can be used to study gravitational effects such as gravitational waves and the universality of the equivalence principle. On one hand, the possibility of carrying out experiments to probe gravity using quantum systems opens an avenue to deepen our understanding of the overlap of these theories. On the other hand, incorporating relativity in quantum technologies promises the development of a new generation of relativistic quantum applications of relevance in Earth-based and space-based setups. In this talk, I will introduce a framework for the application of quantum information and quantum metrology techniques to relativistic quantum fields. I will show how, using this framework, we have been able to develop an accelerometer and a gravitational wave detector which exploit both quantum and relativistic effects. Moreover, our framework can be used to estimate with high precision spacetime parameters such as the Earth's Schwarzchild radius and the gravitational constant.
From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg

S. James Gates Jr. University of Maryland, College Park

June 04, 2014

PIRSA:14060048

The concept of supersymmetry, though never observed in nature, has driven a great deal of research in theoretical physics over the past several decades. Much has been learned through this research, but many unresolved questions remain. This presentation will describe how these questions can lead one down a surprising path: toward the dodecaphony of Austrian composer Arnold Schoenberg.

Title	Date	Collection	Type	Info
Frequency comparison of cryogenic optical lattice clocks	2014‑06‑16	New ideas in low-energy tests of fundamental physics	Conference	View details
Zen and the art of atomic time-keeping (Tutorial on atomic clocks for particle theorists)	2014‑06‑16	New ideas in low-energy tests of fundamental physics	Conference	View details
Atomic Clocks and Tests of Fundamental Physics	2014‑06‑16	New ideas in low-energy tests of fundamental physics	Conference	View details
Introduction, Scope and goals of the workshop, Open questions in the field	2014‑06‑16	New ideas in low-energy tests of fundamental physics	Conference	View details
Welcome	2014‑06‑16	New ideas in low-energy tests of fundamental physics	Conference	View details
What Can We Learn from Precision Higgs	2014‑06‑13	Particle Physics	Scientific Series	View details
Inflation, Variable Speed of Light and BICEP2	2014‑06‑12	Cosmology and Gravitation	Scientific Series	View details
Sequential growth dynamics and quantum random walks	2014‑06‑11	Colloquium	Scientific Series	View details
Wild and tame scalar-tensor black holes	2014‑06‑10	Cosmology and Gravitation	Scientific Series	View details
Neutrino Wakes	2014‑06‑06	Colloquium	Scientific Series	View details
Quantum technologies as tools to deepen our understanding of quantum theory and relativity	2014‑06‑05	Perimeter Institute Quantum Discussions	Scientific Series	View details
From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg	2014‑06‑04	Public Lecture Series	Public Lectures	View details

Search Talks

Format results