# Research

I am a theoretical physicist whose primary interests lie in classical and quantum black holes, although I have also pursued investigations in particle physics and numerical modeling. I welcome students to inquire about participating in these projects.

In 2018, I was awarded LMU's Elizabeth and Michael Rudinica Award for Student-Faculty Research.

I am also a KITP Scholar at the Kavli Institute for Theoretical Physics in Santa Barbara.

## Gravitation and Cosmology

My research centres on modified theories of gravity and their phenomenological implications for particle physics and cosmology. Recent focus has been on quantum corrected metric solutions with a minimum length, *i.e.* the existence of a characteristic scale at which classical physics transitions to a quantum regime. The latest observational data -- most importantly those forthcoming from LIGO and the Event Horizon Telescope -- present new insight into what could be our first glimpse of quantum gravity effects. Identifying such signatures of current models that can subsequently be constrained by this data is an immediate and compelling task.

Current areas of focus include:

**Quantum Gravity Corrected Black Holes**

There exists a threshold scale at which quantum gravity effects become important. Such a minimal length emerges naturally in a number of areas, including string theory, loop quantum gravity, non-commutative geometries, and generalized uncertainty principles (GUP). I have shown that such black holes allow for dimensional reduction at the Planck scale, an intriguing new window on quantum gravity phenomenology. GUP black holes may also be suitable candidates for dark matter.

**Lower Dimensional Gravity**

A variety of approaches to quantum gravity predict that the effective dimension of spacetime reduces at high energies. Several viable string-inspired methods have recently been proposed to model such dimensional transitions. The unconventional nature of gravity in lower dimensions points to novel -- and moreover experimentally-testable -- consequences for both high energy physics and early-universe cosmology, thus making this an intriguing area of exploration.

My most significant work in this area explored the impact of generic dimensional reduction on black hole thermodynamics and their potential phenomenological signatures. I proposed that such a signature could manifest itself as a fundamental gravitational wave cut-off frequency marking the effective dimension drops below (3+1)-D, a threshold which is in principle detectable by future space-based gravity wave observatories.

**Future Investigations**

Black hole physics is entering a golden age. A century after Einstein proposed his celebrated theory of General Relativity, two key experiments are providing new data that promise to revolutionize the field: the Laser Interferrometer Gravitational Wave Observatory (LIGO), and the Event Horizon Telescope (EHT). LIGO has already ushered in the era gravitational wave astronomy, allowing us for the first time to probe the Universe beyond the electromagnetic spectrum. Through this window, we will be able to test black hole mergers, coalescence, and ringdowns with high precision. Conversely, the EHT is expected to reveal such novel characteristics as "black hole shadows" -- *i.e.* regions surrounding black holes from which no light escapes -- which will provide unprecedented tests of gravitational physics at the event horizon.

I am interested in exploring potential macroscopic signatures of quantum gravity in such supermassive black holes. These include aspects of the information paradox and Hawking radiation as they relate to near-horizon physics. The prospective imaging of the black hole shadow by the EHT and related experiments could reveal hints of related quantum effects on scales of the horizon. These could be within the sensitivity of the experiments, and thus experimentally testable.

## Athletics Modeling

My research in this area focuses on building realistic mathematical and computational models of sprint performances, accounting for atmospheric drag (wind and altitude effects). Recent studies have also examined the effects of temperature, humidity level, and atmospheric pressure on sprint race times.

**Drag assistance calculators for the short sprints:**

Mercier Scoring Tables:

## Interdisciplinary Research

Fractal and multifractal analysis is a natural way of identifying scale-invariant behavior manifest in seemingly random distributions. This provides a truly interdisciplinary tool with which one can study structures literally ranging from the extra-galactic realm of the cosmos to the psychophysical world of the canvas.

It has been shown that many works of art possess such hierarchical patterns. These are not only physically distributed on the canvas as blobs of paint, but also are resolved at various stages of visual processing. This phenomenon could help unlock the mechanisms of cognitive control during the painting process, and could moreover provide a method of identifying ar forgeries.

**Related research papers:**

J. R. Mureika and R. P. Taylor, The Abstract Expressionists and Les Automatistes: a Shared Multifractal Depth?, Signal Proc.

**93**, 573-578 (2013)J. R. Mureika, Fractal Dimensions in Perceptual Color Space: A Comparison Study Using Jackson Pollock's Art, Chaos

**15**, 043702 (2005)J. R. Mureika, C. C. Dyer, G. C. Cupchik, On Multifractal Structure in Non-Representational Art, Phys. Rev.

**E 72**, 046101 (2005)J. R. Mureika, G. C. Cupchik, C. C. Dyer, Multifractal Fingerprints in the Visual Arts, Leonardo

**37**, 53-56 (2004)