Steven Dorsher

Former Computational Physicist

I have had a 15+ year research career in physics and astronomy over the course of my bachelors degree, three masters degrees, and since my final graduation. Most of this (10+ years) has been in computational physics. My primary focus is in general relativity, black holes, and gravitational waves. I have also done research in cosmology, particle physics, neutrinos, exoplanets, the three body Newtonian gravity problem, and fractional calculus.

I have 8 main publications/documents and about 35 total including membership in LIGO spanning the time of the first three detections.

My background is primarily in scientific programming, in the context of data analysis algorithms, experiment development and assessment, and numerical methods for theory.

Education

MS Physics, LSU, December 2017. Multiple advisors and supervisors, at the time of graduation, Jorge Pullin
MS Physics, U of MN, July 2013. Mulitple advisors and supervisors. For NOνA, Ronald Poling. At the time of graduation, Joseph Kapusta signed off as Department Chair.
MS Astronomy, Ohio State, August 2006. Advisor: Andrew Gould
BS Physics, MIT, June 2004. Advisor: Jacqueline Hewitt

Computational work

LSU Masters work in general relativity and gravitational waves

C++ EMRI code I wrote for my masters at LSU Simulation of a scalar field model of an extreme mass ratio inspiral black hole binary on a Schwarszchild background in General Relativity
FORTRAN EMRI Code my advisor provided for me to port to C++ LSUMy C++ black hole binary simulation was ported from this FORTRAN code supplied by my advisor
Python error convergence analysis An analysis of my advisors original FORTRAN code and its truncation and roundoff error with discontinuous Galerkin order and multipole moment mode numbers
Masters Exam Paper at LSUDocumentation for the research mentioned above, 70 pages of work toward a thesis submitted for a successful masters exam
Go to "generalexammainfile.pdf" here for Masters Exam Paper from LSU since the Research Gate link seems to keep breaking and I don't seem to be able to update this on the Github Homepage

University of Minnesota and LSU LIGO gravitational wave detector masters work

Radon transform spectrogram gravitational wave search article This is an article on NASA's preprint arXiv about a gravitational wave search I wrote. My contribution is section V.B. and figure 4, especially. I personally no longer possess the code and am unsure whether or not it is in use, though similar code certainly is still used to make gravitational wave detections
Gravity Gradient Noise simulation, LIGO I no longer have the code for this either, also written in MATLAB
LIGO Event Trigger DatabaseI was a member of the LIGO Scientific Collaboration during the time of the first few detections and for several years before. Oh yeah also I wrote a terrible database in Java and HBase
Documentation for that prototype database
Short sample of fourier transforms in MatlabWritten in two weeks before I lost access more than a decade ago. Just wanted to prove I had been using it for two years after I lost access to my gravitational wave search code and the gravity gradient noise simulations I wrote there.

Previous work at Ohio State (masters) and MIT (undergrad), as well as independent post-graduate work

Exoplanets paper. I no longer have the code, written in FORTRAN at Ohio State for a masters in astronomy. Early exoplanet statistics analysis using Monte Carlo methods to simulate a line of sight in the galaxy to realistically determine the observable population of stars in the OGLE-III lensing survey, and hence the fraction of stars with planets.
Undergrad ThesisWritten in C, I no longer have the code. This was a Monte Carlo simulation to assess the feasibility of using Einstein ring radii to measure the cosmological constant and matter density of the universe based on strong gravitational lens systems known at the time.
Python Newtonian Gravity three body orbits codeThis numerically solves a differential equation to plot an orbit and compute the energy transfer between a planet and an inner binary star system. I have verified that it is not a numerical artifact of the simulation.

Student research at Saint Cloud State University on Fractional Calculus

Digital Fractional Order Differentiator and Integrator Simulation I developed and wrote this algorithm in C++
First author paper on the fractional calculus algorithm, submitted eons ago but not published, honestly I don't know how and it wouldn't be possible anymore

Class projects

Tiny black hole image codeHere I created an image of the sky as seen around a black hole (think Gargantua from Interstellar, only way more disappointing due to image resolution) using a small amount of compute time on 4 processes for a class with mpi4py
Black hole image final project writeup
Converts between astronomical timesWritten a long time ago for a class. No promises

Tiny black hole image I made

Other Skills

Python (roughly 3 years equivalent over 5 years, not daily)

C++ (4.5 years) and C (1.5 years)

Fortran (5 years)

Other previous experience with:

Matlab (2.5 years)
Java (1 year)

Technically have used:

Bash
Scheme
Haskell

Databases

Pandas
A little SQL
A little HBase

Very minimal parallel programming experience with

OpenMP
MPI
mpi4py

Machine Learning-- beginner level, certificates, need practical experience still, mostly guided projects so far

Data Cleaning
Visualization
Regression-- linear, relu, logistic, tanh, softmax
Classification
Clustering
Neural Networks
Convolutional Filtering
Adam optimizer
Batch filter
Recurrent Neural Networks
Maybe: Transformers
Maybe: GRUs, LTSMs
Guided Projects in: phrase generation, image recognition and object detection and location, music generation, activation word detection (and overlay of beep), facial recognition and authorization, video game starship lander trajectory prediction, French to English translation (though that was very heavily guided and my French is very beginner)
Mathematical calculation of more precise technique for cosine similarity (it is possible a reference was given but I computed it instead)

Languages

--though my hearing is not amazing (though seriously, people with glasses can often see just fine, but my hearing is worse than average and I don't have hearing aids)

ENGLISH--native speaker

Danish--I've finished the Duolingo track though have little practical experience speaking it

French--High school in 2000 though I have begun studying it on Duolingo again

I am just beginning to study German, Turkish, and Spanish but these don't really count as skills at this time

RESUME, CV, GITHUB, PUBLICATIONS, AND TRANSCRIPTS

Accuracy has been my specialization, though not exclusively, whether in theoreticaly computing, the statistics of data analysis, the simulation of experiments, or development of algorithms.

Degrees verifiable online

my four diplomas which are in my name Susan Dorsher, MS LSU physics 2017, MS Ohio State astronomy 2006, MS UMN physics 2013, BS physics MIT 2004

Certificates

Deep Learning Specialization; Coursera; DeepLearning.AI

Neural Networks and Deep Learning

Improving Deep Neural Networks: Hyperparameter Tuning, Regularization, and Optimization

Structured Machine Learning Projects

Convolutional Neural Networks

Sequence Models, Specialization Certificate

Machine Learning Specialization; Coursera; DeepLearning.AI; Stanford

Coursera; Google; discontinued due to inability to finance BigQuery

DataQuest Data Science Certificates

Job status/teaching certificates

Links

Other professional portfolio websites, and about-me's

Contact Information

You can reach me most easily by email:

dorsher@alum.mit.edu

On names and ID: My degrees were granted under the name of Susan Dorsher, which is my legal name (associated with the credit card on this account FYI and I have sent LinkedIn ID in the form of my passport card and MN state ID). The majority of my publications are under Steven Dorsher (please see ORCID or ResearchGate where both names are listed) to reflect the name I have used personally and professionally since 2009. Please, I go by Steven.

This is my real name and identity. I do not have alternate identities. My Guild Wars 2: WaveIn; SWTOR legacy: Dreamstar. FFXIV: will update when I remember. MIT & 90's: eirl; Legend's LARPing in 2000's: Aurbren

Contact

Steven Dorsher

St Cloud, MN

Sometimes, Crosslake MN or Minneapolis MN

952-686-1925

320-406-3784

dorsher@alum.mit.edu

sdorsher@gmail.com

steven.susan.dorsher@outlook.com

me in an arml high scorer sweater I won in iowa on mn maroon gold as a teen

Bookshelves in office where I teach at home, blue striped sweater.

I am frankly not very photogenic, seriously, its too bad you cant laugh at this, but anyhow nobody ever puts me in a group photo. my mom was kind enough to pose with me at LIGO Livingston. I worked on LIGO at LSU, immediately nearby. Mom doesnt want me to use her photo on my professional website, cant imagine why. Thanks to mom for everything

Just me in some clothes, long sleeve bluish green sweater, tshirt underneath, long pants, tennis shoes, winter hat. I also have glasses and a beard. Body is... vague, but fat.