Professor Joe Straley

Department of Physics and Astronomy

University of Kentucky

Host: Brad Plaster

Title: TBA

Abstract: TBA

Professor Joe Straley

Department of Physics and Astronomy

University of Kentucky

Host: Brad Plaster

Title: TBA

Abstract: TBA

The 2023 Andrew Chamblin Memorial Colloquium

http://andrewchamblin.org/lecture.html

Speaker:  Dr. Vijay Balasubramanian

Professor

University of Pennsylvania

Title:  The entropy of black holes

Abstract:  One of the most famous results of twentieth-century physics states that black holes carry an entropy proportional to the area of their horizons. This entropy formula is universal in general relativity: it applies to black holes with any mass, charge, or rotation, and in any spacetime dimension.  I will describe a recent proposal explaining the microscopic origin and universality of this formula.  The proposal exploits new developments in the study of many-body chaos, thermalization, and quantum dynamics, along with concepts of complexity and information from theoretical computer science, communications theory, and cryptography.  These developments also suggest that the interior of a black hole is causally accessible to external observers, but only if they can perform egregiously complex measurements that are inaccessible under normal conditions.

The 2023 Andrew Chamblin Memorial Colloquium

http://andrewchamblin.org/lecture.html

Speaker:  Dr. Vijay Balasubramanian

Professor

University of Pennsylvania

Title:  The entropy of black holes

Abstract:  One of the most famous results of twentieth-century physics states that black holes carry an entropy proportional to the area of their horizons. This entropy formula is universal in general relativity: it applies to black holes with any mass, charge, or rotation, and in any spacetime dimension.  I will describe a recent proposal explaining the microscopic origin and universality of this formula.  The proposal exploits new developments in the study of many-body chaos, thermalization, and quantum dynamics, along with concepts of complexity and information from theoretical computer science, communications theory, and cryptography.  These developments also suggest that the interior of a black hole is causally accessible to external observers, but only if they can perform egregiously complex measurements that are inaccessible under normal conditions.

Speaker: Patricia Rankin

Professor and Department Chair

Arizona State University

Department of Physics

Host: Plaster

Title: Physics is Fun! Everyone should do it

Abstract: Patricia Rankin became a physicist because she enjoyed it. She still enjoys it. She remembers being asked as a student why more women didn’t study physics. She can now give a much better answer to that question. This talk looks at how physicists solve problems, and why how we think impacts the demographics of our field. She will discuss how our understanding of what makes people leave physics has evolved and why the focus is now on a process driven approach. She will argue that while the field would benefit from more diversity, what matters to an individual is that they get to do what they enjoy and feel welcome.

Speaker: Patricia Rankin

Professor and Department Chair

Arizona State University

Department of Physics

Host: Plaster

Title: Physics is Fun! Everyone should do it

Abstract: Patricia Rankin became a physicist because she enjoyed it. She still enjoys it. She remembers being asked as a student why more women didn’t study physics. She can now give a much better answer to that question. This talk looks at how physicists solve problems, and why how we think impacts the demographics of our field. She will discuss how our understanding of what makes people leave physics has evolved and why the focus is now on a process driven approach. She will argue that while the field would benefit from more diversity, what matters to an individual is that they get to do what they enjoy and feel welcome.

Dr. NandiniTrivedi

Professor

Ohio State University

Host: Murthy

Title: Fractionalized excitations in Quantum Spin Liquids and their Detection

Abstract: The 2022 Nobel prize celebrates the detection of entanglement between two photons. Quantum spin liquids (QSLs) are long-range entangled states of matter of billions of interacting qubits or spins that develop in a Mott insulator. The fate of the interacting spins can progress along two paths as the temperature is lowered: the spins can undergo long range ordering, spontaneously breaking the continuous symmetries, leading to a magnetic phase; or the spins can remain disordered but get quantum mechanically entangled with long range patterns of many-body entanglement in the resultant QSL. The possibility of obtaining QSL phases is enhanced by having a low spin and enhanced quantum fluctuations, and frustration arising from the lattice geometry and/or competing spin-spin interactions. Remarkably QSLs harbor fractionalized excitations rather than the conventional spin waves of ordered magnets that carry integer units of angular momentum. In my talk I will identify detectable signatures of these fractionalized excitations in experiments using light and neutrons. These fractionalized excitations are promising candidates to create logical qubits for quantum computation. 

Dr. NandiniTrivedi

Professor

Ohio State University

Host: Murthy

Title: Fractionalized excitations in Quantum Spin Liquids and their Detection

Abstract: The 2022 Nobel prize celebrates the detection of entanglement between two photons. Quantum spin liquids (QSLs) are long-range entangled states of matter of billions of interacting qubits or spins that develop in a Mott insulator. The fate of the interacting spins can progress along two paths as the temperature is lowered: the spins can undergo long range ordering, spontaneously breaking the continuous symmetries, leading to a magnetic phase; or the spins can remain disordered but get quantum mechanically entangled with long range patterns of many-body entanglement in the resultant QSL. The possibility of obtaining QSL phases is enhanced by having a low spin and enhanced quantum fluctuations, and frustration arising from the lattice geometry and/or competing spin-spin interactions. Remarkably QSLs harbor fractionalized excitations rather than the conventional spin waves of ordered magnets that carry integer units of angular momentum. In my talk I will identify detectable signatures of these fractionalized excitations in experiments using light and neutrons. These fractionalized excitations are promising candidates to create logical qubits for quantum computation. 

Dr. Heidi Wu

Assistant Professor

Boise State University

Host: Su

Title: Probing Cosmic Acceleration with Galaxy Clusters

Abstract: The accelerated expansion of the Universe is one of the biggest puzzles in physics: Why is gravity repulsive rather than attractive on distance scales larger than a few million lightyears? Cosmic acceleration slows down the growth of structure, and we can use galaxy clusters — the largest gravitationally bound objects in the Universe — to probe the nature of cosmic acceleration.  In this talk, I will first introduce our current understanding of the Universe.  I will then discuss how we use sky surveys of galaxy clusters to measure cosmic acceleration and how several ambitious ground- and space-based missions will revolutionize our understanding of the Universe.

Dr. Heidi Wu

Assistant Professor

Boise State University

Host: Su

Title: Probing Cosmic Acceleration with Galaxy Clusters

Abstract: The accelerated expansion of the Universe is one of the biggest puzzles in physics: Why is gravity repulsive rather than attractive on distance scales larger than a few million lightyears? Cosmic acceleration slows down the growth of structure, and we can use galaxy clusters — the largest gravitationally bound objects in the Universe — to probe the nature of cosmic acceleration.  In this talk, I will first introduce our current understanding of the Universe.  I will then discuss how we use sky surveys of galaxy clusters to measure cosmic acceleration and how several ambitious ground- and space-based missions will revolutionize our understanding of the Universe.