The Unruh Fest: A Celebration in Honour of Bill Unruh's 70th Birthday

Conference Date: 
Thursday, August 13, 2015 (All day) to Friday, August 14, 2015 (All day)
Scientific Areas: 
Quantum Gravity

 

A workshop in honour of Bill Unruh on occasion of his 70th birthday.

Registration for this event is now closed.

  • Valeri Frolov, University of Alberta
  • Stephen Fulling, Texas A&M University
  • Masahiro Hotta, Tohoku University
  • Ted Jacobsen, University of Maryland
  • Raymond Laflamme, Institute for Quantum Computing
  • George Matsas, Instituto de Física Teórica, Universidade Estadual Paulista
  • Jonathan Oppenheim, University College London
  • Marek Radzikowski, American University of Afghanistan
  • Benni Reznik, Tel Aviv University
  • Ralf Schuetzhold, Universitat Duisburg-Essen
  • Robert Wald, University of Chicago
  • Silke Weinfurtner, University of Nottingham
  • Bruno Arderuci, University of British Columbia
  • Kaca Bradonjic, Wellesley College 
  • Bianca Dittrich, Perimeter Institute
  • Valeri Frolov, University of Alberta
  • Stephen Fulling, Texas A&M University
  • Henrique Gomes, Perimeter Institute
  • Stephen Green, Perimeter Institute
  • Masahiro Hotta, Tohoku University
  • Ted Jacobsen, University of Maryland
  • Farbod Kamiab, Perimeter Institute
  • Achim Kempf, Perimeter Institute & University of Waterloo
  • Raymond Laflamme, Institute for Quantum Computing
  • Morgan Lynch, University of Wisconsin-Milwaukee
  • Eduardo Martin-Martinez, Perimeter Institute & University of Waterloo
  • George Matsas, Instituto de Física Teórica, Universidade Estadual Paulista
  • Robert Myers, Perimeter Institute
  • Jonathan Oppenheim, University College London
  • Eric Poisson, University of Guelph
  • Marek Radzikowski, American University of Afghanistan
  • Benni Reznik, Tel Aviv University
  • Ralf Schuetzhold, Universitat Duisburg-Essen
  • Barak Shoshany, Perimeter Institute
  • Vasudev Shyam, Perimeter Institute
  • Lee Smolin, Perimeter Institute
  • Rafael Sorkin, Perimeter Institute
  • Fumika Suzuki, University of British Columbia
  • Bill Unruh, University of British Columbia
  • Robert Wald, University of Chicago
  • Silke Weinfurtner, University of Nottingham
  • Steven Weinstein, Perimeter Institute * University of Waterloo
  • Yasaman Yazdi, Perimeter Institute
  • Nosiphiwo Zwane, Perimeter Institute

Thursday, August 13, 2015

Time

Event

Location

8:30 – 9:00am

Registration

Reception

9:00 – 9:05am

Silke WeinfurtnerUniversity of Nottingham
Welcome to "The Unruh Fest"

Bob Room

9:05 – 10:00am

Robert Wald, University of Chicago
Information Loss

Bob Room

10:00 – 10:30am

Coffee Break

Bistro – 1st Floor

10:30 – 11:30am

Jonathan Oppenheim, University College London
What are the laws of quantum thermodynamics? 

Bob Room

11:30 – 12:30pm

Marek Radzikowski, American University of Afghanistan
Microlocal analysis in quantum field theory on curved spacetime and related topics

Bob Room

12:30 – 2:00pm

Lunch

Bistro – 2nd Floor

2:00 – 3:00pm

Stephen Fulling, Texas A&M University
Acceleration Radiation:  The Prophet and the Heretics

Bob Room

3:00 – 4:00pm

Raymond Laflamme, Institute for Quantum Computing
Experimental Quantum Error Correction

Bob Room

4:00 – 4:10pm

Conference Photo

TBA

4:10 – 4:30pm

Coffee Break

Bistro – 1st Floor

4:30 – 5:30pm

Silke Weinfurtner, University of Nottingham
Hydrodynamic simulations of rotating and non-rotating black holes

Bob Room

5:30 – 6:00pm

Wilhelm E. Nassau
The Third Man, Exciting Events in Post War Vienna

Bob Room

7:00 – 9:00pm

Banquet

Bistro – 2nd Floor

 

Friday, August 14, 2015

Time

Event

Location

9:00 – 10:00am

 Valeri Frolov, University of Alberta
Mass gap for  black hole formation in higher derivative and ghost-free gravity

Bob Room

10:00 – 10:30am

Coffee Break

Bistro – 1st Floor

10:30 – 11:30am

Masahiro Hotta, Tohoku University
Consciousness Does Not Cause Quantum Zeno Effect

Bob Room

11:30 – 12:30pm

George Matsas,
Instituto de Física Teórica, Universidade Estadual Paulista
On the Observability of the Unruh Effect

Bob Room

12:30 – 2:00pm

Lunch

Bistro – 2nd Floor

2:00 – 3:00pm

Ted Jacobson, University of Maryland
Fun with ideal plasmas

Bob Room

3:00 – 4:00pm

Benni Reznik, Tel Aviv University
Lattice gauge theories with cold atoms

Bob Room

4:00 – 4:30pm

Coffee Break

Bistro – 1st Floor

4:30 – 5:30pm

Ralf Schuetzhold, Universitat Duisburg-Essen
On the partner particles for black hole evaporation

Bob Room

5:30 – 6:00pm

Discussion

Bob Room

 

Valerie Frolov, University of Alberta

Mass gap for  black hole formation in higher derivative and ghost-free gravity

The problem of the gravitational collapse of small mass in the higher derivative and ghost free theories of gravity is discussed. It will be demonstrated how higher derivative and non-local modifications of gravity equations regularizes static and dynamical solutions. Boosting a static solution of the linearized equations for the gravitational potential of a point mass we obtain a solution for the field of the ultra-relativistic source (gyraton). Using the latter we construct solutions for the collapsing spherical (thin and thick) null shell. By analysing the obtained solutions we demonstrate that for small enough value of the mass M an apparent horizon is not formed for the gravitational collapse of small mass in the higher-derivative and ghost free theories of gravity. We demonstrate that this “mass gap” property is connected with the presence of the UV cut-off in such theories. 

Stephen Fulling, Texas A&M University

Acceleration Radiation:  The Prophet and the Heretics

I review the contentious question, "Does a uniformly accelerated detector radiate?"  As Audretsch and Muller pointed out long ago, this is partly a semantic dispute.  The
talk draws on recent discussions with Alex Calogeracos and George Matsas.

Masahiro Hotta, Tohoku University

Consciousness Does Not Cause Quantum Zeno Effect

The quantum Zeno effect is often very controversial in the context of consciousness problems.  Frequent direct measurements of a quantum system freeze its time evolution.  Then what happes if an observer continuously watches a Schrodinger's cat from the start of the experiment? 
 
Naively this looks like a yes-no measurement of a unstable atom decay, which emits a gamma ray as a trigger of the cat execution.  If so, the continuous cat observation may prevent the ray emission as a Zeno effect. Consequently the cat can remain alive as long as the observation is maintained. However, this is clearly incorrect. In this talk, assuming some natural conditions, we generally prove the impossibility of quantum Zeno effects generated by indirect measurements by the observer's consciousness.
 
Ted JacobsonUniversity of Maryland
 
Fun with ideal plasmas
 
I will sketch a few interesting phenomena involving ideal plasmas, including
helicity conservation, frozen flux, the Blandford-Znajek mechanism, and self-confined Poynting jets, using the language of differential forms. 
 
Raymond LaflammeInstitute for Quantum Computing
 
Experimental Quantum Error Correction
 
The last decade has seen the impressive development of quantum information science, both in theory and in experiment. There are many measures that can be used to assess the achievements in the field: new algorithms, new applications and larger quantum processors, to name a few. The discovery of quantum algorithms has demonstrated the potential power of quantum information. 
As pointed out by Bill some years ago, to realize this potential requires the ability to overcome the imprecision and imperfection inherent in physical systems.
Quantum error correction (QEC) has provided a solution, showing that errors can be corrected with a reasonable amount of resources as long as their rate is sufficiently small. Implementing QEC protocols remains one of the most important challenges in QIP.
In the experimental arena, the quest to build quantum processors that could outperform their classical counterparts has led to many blueprint proposals for potential devices based on NMR, electron spin resonance, ion traps, atom traps, optics, superconducting devices and nitrogen-vacancy centres, among others. Many have demonstrated not only the possibility of controlling quantum bits, but also the ability to do so in practice, showing the progression of quantum information science from the blackboard to the laboratory. My presentation will give an overview of some of the recent results in quantum information science on the way to implement quantum error correction.  I will show how noise can be characterise efficiently when our goal is to find suitable quantum error correcting codes. I will show demonstrations of control to implement some quantum error correcting codes and finally how can noise be extracted through algorithmic cooling. I will comments on some challenges that need to be solved and a path towards implementing many round of quantum error correction.
 
George Matsas, Universidade Estadual Paulista
 
On the Observability of the Unruh Effect
 
This year marks the 40’th anniversary of the  Unruh effect as described at the first Marcel Grossmann meeting in 1975. We revisit it with  emphasis on the observability issue which might be a concern  at first sight, since the linear acceleration needed to reach a temperature 1 K is of order 10^20 m/s^2 . We close the talk by emphasizing that the Unruh effect does not require any verification beyond that of  relativistic free field theory itself. The Unruh effect lives among us.   
 
Jonathan Oppenheim, University College London
 
What are the laws of quantum thermodynamics? 
 
Marek Radzikowski, American University of Afghanistan
 
Microlocal analysis in quantum field theory on curved spacetime and related topics
 
Presented is a discussion of quantum field theory on curved spacetime and of microlocal analysis, with an emphasis on the way that these two areas connected for me personally through a specific problem, namely that of resolving Kay's singularity conjecture for two point functions of a linear scalar field on a globally hyperbolic spacetime. A particular case of this conjecture is presented, namely the translation invariant case on flat Minkowski spacetime, which does not require microlocal analysis. Next, the results of Duistermaat and Hoermander concerning distinguished parametrices of the Klein Gordon equation on a curved spacetime are described, since they lead to the notion of a wave front set (or microlocal) spectral condition, which could be viewed as a remnant of the spectral condition on flat spacetime. This condition on the wavefront set of the two point function has been employed by Brunetti, Koehler and Fredenhagen to develop a method of renormalization on a general curved spacetime, which has been developed further by Hollands and Wald. Other QFT-related topics to which microlocal methods may apply are: Lorentz symmetry breaking models and many body QM models (e.g., the free electron gas in a metal). In the case of vector or spinor models, the polarization set may be used to refine information about the singularities. Similarly, the principal symbol of the two point function, viewed as a Fourier integral operator, is a constant times a canonical half density on the natural Lagrangian submanifold associated with the Klein-Gordon operator, suggesting a tangent space Lorentz invariance property for the free model.
 
Benni Reznik, Tel Aviv University
 
Lattice gauge theories with cold atoms
 
Can high energy physics can be simulated by low-energy, nonrelativistic, many-body systems, such as ultracold atoms? Ultracold atomic systems lack the type of symmetries and dynamical properties of high energy physics models: in particular, they do not manifest local gauge invariance nor Lorentz invariance, which are crucial properties of the quantum field theories which are the building blocks of the standard model of elementary particles. 
However, it will be shown that there are ways to configure atomic system to manifest both local gauge invariance and Lorentz invariance. In particular, local gauge invariance can arise either as an effective, low energy, symmetry, or as an "exact" symmetry, following from the conservation laws in atomic interactions. Such quantum simulators may lead to new type of (table-top) experiments,  to test various QCD phenomena, as the confinement of dynamical quarks, phase transitions, and other effects. 
 
Ralf ScheutzholdUniversitat Duisburg-Essen
 
On the partner particles for black hole evaporation
 
Due to the linearity of the field equations and the resulting bilinear structure of the Hamiltonian, quantum radiation effects such as black hole evaporation or particle creation in an expanding universe are typically described as (squeezing) processes where particles are created in pairs.
Here, we address the following question: given a mode (e.g., wave-packet) corresponding to a created particle (e.g., as part of Hawking radiation), what is its partner, i.e., the other particle of the pair?
After a general derivation of this partner mode, we will discuss some examples such as moving mirror radiation and speculate about possible implications for the black hole information puzzle.
 
Robert Wald, University of Chicago
 
Information Loss
 
It is argued that information is lost in the process of black hole formation and evaporation.
 
Silke Weinfurtner, University of Nottingham
 
Hydrodynamic simulations of rotating and non-rotating black holes
 
In 1981 Bill discovered an analogy between the propagation of fields in the vicinity of
astrophysical black holes and the that of small excitations in fluids. He postulated that this 
analogy allows one to test, challenge and verify, in tabletop experiments, the elusive 
processes of black hole mass and angular momentum loss. Indeed, 34 years later 
analogue gravity experiments are carried out all over the world to implement his idea. 
 
I will first present a brief overview on analogue black hole experiments,
and then discuss in more detail some of my earlier (in collaboration with Bill) and more recent
experimental and theoretical results on the subject.
 
 
 
 
 

 

 

 

Friday Aug 14, 2015
Speaker(s): 

Due to the linearity of the field equations and the resulting bilinear structure of the Hamiltonian, quantum radiation effects such as black hole evaporation or particle creation in an expanding universe are typically described as (squeezing) processes where particles are created in pairs.
Here, we address the following question: given a mode (e.g., wave-packet) corresponding to a created particle (e.g., as part of Hawking radiation), what is its partner, i.e., the other particle of the pair?

Scientific Areas: 
 

 

Friday Aug 14, 2015
Speaker(s): 

Can high energy physics can be simulated by low-energy, nonrelativistic, many-body systems, such as ultracold atoms? Ultracold atomic systems lack the type of symmetries and dynamical properties of high energy physics models: in particular, they do not manifest local gauge invariance nor Lorentz invariance, which are crucial properties of the quantum field theories which are the building blocks of the standard model of elementary particles.

Scientific Areas: 
 

 

Friday Aug 14, 2015
Speaker(s): 

I will sketch a few interesting phenomena involving ideal plasmas, including helicity conservation, frozen flux, the Blandford-Znajek mechanism, and self-confined Poynting jets, using the language of differential forms.

Scientific Areas: 
 

 

Friday Aug 14, 2015
Speaker(s): 

This year marks the 40’th anniversary of the Unruh effect as described at the first Marcel Grossmann meeting in 1975. We revisit it with emphasis on the observability issue which might be a concern at first sight, since the linear acceleration needed to reach a temperature 1 K is of order 10^20 m/s^2 . We close the talk by emphasizing that the Unruh effect does not require any verification beyond that of relativistic free field theory itself. The Unruh effect lives among us.

Scientific Areas: 
 

 

Friday Aug 14, 2015
Speaker(s): 

The quantum Zeno effect is often very controversial in the context of consciousness problems.
Frequent direct measurements of a quantum system freeze its time evolution.
Then what happes if an observer continuously watches a Schrodinger's cat from the start of the experiment?
Naively this looks like a yes-no measurement of a unstable atom decay, which emits a gamma ray as a trigger of the cat execution.

Scientific Areas: 
 

 

Friday Aug 14, 2015
Speaker(s): 

The problem of the gravitational collapse of small mass in the higher derivative and ghost free theories of gravity is discussed. It will be demonstrated how higher derivative and non-local modifications of gravity equations regularizes static and dynamical solutions. Boosting a static solution of the linearized equations for the gravitational potential of a point mass we obtain a solution for the field of the ultra-relativistic source (gyraton). Using the latter we construct solutions for the collapsing spherical (thin and thick) null shell.

Scientific Areas: 
 

 

Thursday Aug 13, 2015
Speaker(s): 

In 1981 Bill discovered an analogy between the propagation of fields in the vicinity of
astrophysical black holes and the that of small excitations in fluids. He postulated that this
analogy allows one to test, challenge and verify, in tabletop experiments, the elusive
processes of black hole mass and angular momentum loss. Indeed, 34 years later
analogue gravity experiments are carried out all over the world to implement his idea.

Scientific Areas: 
 

 

Thursday Aug 13, 2015
Speaker(s): 

The last decade has seen the impressive development of quantum information science, both in theory and in experiment. There are many measures that can be used to assess the achievements in the field: new algorithms, new applications and larger quantum processors, to name a few. The discovery of quantum algorithms has demonstrated the potential power of quantum information.
As pointed out by Bill some years ago, to realize this potential requires the ability to overcome the imprecision and imperfection inherent in physical systems.

Scientific Areas: 

Pages

Scientific Organizers:

Matt Choptuik, University of British Columbia
Ralf Schuetzhold, Duisburg-Essen University
Silke Weinfurtner, University of Nottingham