Conference

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Time and frequency metrology at NIST

Jeff Sherman National Institute of Standards and Technology

June 16, 2014

PIRSA:14060011
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
- 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
Dynamical trapping near a quantum critical point

Emanuel Katz Boston University

May 30, 2014

PIRSA:14050116
Functional renormalization group and statistical mechanics of membranes

Omar Zanusso SISSA Scuola Internazionale Superiore di Studi Avanzati

May 30, 2014

PIRSA:14050115
Relativity of non relativistic systems

Federico Piazza Aix-Marseille University

May 30, 2014

PIRSA:14050113
Lattice models for anomalous field theories

John McGreevy University of California, San Diego

May 29, 2014

PIRSA:14050110
Spontaneous symmetry breaking, gravity, and spinning objects

Solomon Endlich Stanford University

May 29, 2014

PIRSA:14050111
Effective theories of vortex lines

Riccardo Penco University of Pennsylvania

May 29, 2014

PIRSA:14050103

Time and frequency metrology at NIST

Jeff Sherman National Institute of Standards and Technology

June 16, 2014

PIRSA:14060011

Official U.S. time is currently realized by an ensemble of commercial cesium-beam atomic clocks and hydrogen masers. Cesium-fountain devices presently serve as ultimate frequency references and help to define the SI second. The present quandary is: these microwave-based standards are rapidly becoming outmatched by new optical atomic frequency references---by a factor of 1,000 in stability, and perhaps a factor of 100 in accuracy. I will survey the ongoing optical atomic clock projects at NIST and highlight related work in optical time and frequency measurement and transfer.
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
- 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
Dynamical trapping near a quantum critical point

Emanuel Katz Boston University

May 30, 2014

PIRSA:14050116

We consider a closed system where the parameter controlling a quantum phase transition is promoted to a dynamical field interacting with the quantum critical theory. In the case that the field has an energy extensive in the volume we can treat its evolution classically. We find that the field can become trapped near the phase transition point due to its interactions with the degrees of freedom of the quantum critical theory. The trapping/untrapping transition can be understood using Kibble-Zurek scaling arguments. We check the general framework numerically in the particular case of the 1D transverse field Ising chain, where the transverse magnetic field is dynamical. This constitutes a dynamical mechanism for tuning a relevant parameter to zero through a non-equilibrium process.
Functional renormalization group and statistical mechanics of membranes

Omar Zanusso SISSA Scuola Internazionale Superiore di Studi Avanzati

May 30, 2014

PIRSA:14050115

We will first review the rich variety of universality classes of membranes and the various models developed to describe their mechanical properties. We will then discuss the recent applications of the non-perturbative renormalization group to these models aimed at improving the understanding of the membranes' phase-space beyond the epsilon-expansion. Finally, we will comment on the implications of these results on various physical systems.
Relativity of non relativistic systems

Federico Piazza Aix-Marseille University

May 30, 2014

PIRSA:14050113

To the best of our knowledge, the fundamental laws of physics are Lorentz invariant. This means that condensed matter systems at finite density still display full Lorentz symmetry: it is just spontaneously broken (i.e. by state considered) and thus non-linearly realized. This simple observation allows to derive exact results about the spectrum of theories at finite charge density and suggests to classify condensed matter systems according to all the inequivalent ways in which boosts can be spontaneously broken.
Lattice models for anomalous field theories

John McGreevy University of California, San Diego

May 29, 2014

PIRSA:14050110
Spontaneous symmetry breaking, gravity, and spinning objects

Solomon Endlich Stanford University

May 29, 2014

PIRSA:14050111

Space-time symmetries are a crucial ingredient of any theoretical model in physics. Unlike internal symmetries, which may or may not be gauged and/or spontaneously broken, space-time symmetries do not admit any ambiguity: they are gauged by gravity, and any conceivable physical system (other than the vacuum) is bound to break at least some of them. Motivated by this observation, I will sketch how to couple gravity with the Goldstone fields that non-linearly realize spontaneously broken space-time symmetries by weakly gauging the Poincare symmetry group in the context of the coset construction. To illustrate the power of this perspective I will build a low energy effective action that describes spinning objects coupled to gravity and describe its interpretation.
Effective theories of vortex lines

Riccardo Penco University of Pennsylvania

May 29, 2014

PIRSA:14050103

Vortex lines are a distinctive feature of superfluids and are characterized by a very peculiar dynamics. In this talk, I will first discuss the behavior of vortex lines in a non-relativistic superfluids in the incompressible limit. I will then introduce an effective theory of vortex lines coupled to sound which applies to relativistic superfluids. I will conclude by briefly discussing the similarities between the effective theory for vortex lines and non-relativistic General Relativity.

Title	Speaker(s)	Date	Talk Type	Info link
Time and frequency metrology at NIST	Jeff Sherman	2014-06-16	Conference	View details
Frequency comparison of cryogenic optical lattice clocks	Hidetoshi Katori	2014-06-16	Conference	View details
Zen and the art of atomic time-keeping (Tutorial on atomic clocks for particle theorists)	Andrei Derevianko	2014-06-16	Conference	View details
Atomic Clocks and Tests of Fundamental Physics	Ekkehard Peik	2014-06-16	Conference	View details
Introduction, Scope and goals of the workshop, Open questions in the field	Asimina Arvanitaki, Derek Jackson Kimball, Maxim Pospelov, Dmitry Budker	2014-06-16	Conference	View details
Welcome		2014-06-16	Conference	View details
Dynamical trapping near a quantum critical point	Emanuel Katz	2014-05-30	Conference	View details
Functional renormalization group and statistical mechanics of membranes	Omar Zanusso	2014-05-30	Conference	View details
Relativity of non relativistic systems	Federico Piazza	2014-05-30	Conference	View details
Lattice models for anomalous field theories	John McGreevy	2014-05-29	Conference	View details
Spontaneous symmetry breaking, gravity, and spinning objects	Solomon Endlich	2014-05-29	Conference	View details
Effective theories of vortex lines	Riccardo Penco	2014-05-29	Conference	View details

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Time and frequency metrology at NIST

Frequency comparison of cryogenic optical lattice clocks

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

Atomic Clocks and Tests of Fundamental Physics

Introduction, Scope and goals of the workshop, Open questions in the field

Welcome

Dynamical trapping near a quantum critical point

Functional renormalization group and statistical mechanics of membranes

Relativity of non relativistic systems

Lattice models for anomalous field theories

Spontaneous symmetry breaking, gravity, and spinning objects

Effective theories of vortex lines

Time and frequency metrology at NIST

Frequency comparison of cryogenic optical lattice clocks

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

Atomic Clocks and Tests of Fundamental Physics

Introduction, Scope and goals of the workshop, Open questions in the field

Welcome

Dynamical trapping near a quantum critical point

Functional renormalization group and statistical mechanics of membranes

Relativity of non relativistic systems

Lattice models for anomalous field theories

Spontaneous symmetry breaking, gravity, and spinning objects

Effective theories of vortex lines