IN THE NEAR FUTURE NEXT-GENERATION TELESCOPES COVERING MOST OF THE ELECTROMAGNETIC SPECTRUM WILL PROVIDE A VIEW INTO THE VERY EARLIEST STAGES OF GALAXY FORMATION. TO ACCURATELY INTERPRET THESE FUTURE OBSERVATIONS ACCURATE AND HIGH-RESOLUTION SIMULATIONS OF THE FIRST STARS AND GALAXIES ARE VITAL. THIS PROPOSAL IS CENTERED ON THE FORMATION OF THE FIRST GALAXIES IN THE UNIVERSE AND THEIR OBSERVATIONAL SIGNATURES IN PREPARATION FOR THESE FUTURE OBSERVATORIES. THIS PROPOSAL HAS TWO OVERALL GOALS: 1. TO SIMULATE THE FORMATION AND EVOLUTION OF A STATISTICALLY SIGNIFICANT SAMPLE OF GALAXIES DURING THE FIRST BILLION YEARS OF THE UNIVERSE INCLUDING ALL RELEVANT ASTROPHYSICS WHILE RESOLVING INDIVIDUAL MOLECULAR CLOUDS IN VARIOUS COSMOLOGICAL ENVIRONMENTS. THESE SIMULATIONS WILL UTILIZE A SOPHISTICATED PHYSICAL MODEL OF STAR AND BLACK HOLE FORMATION AND FEEDBACK INCLUDING RADIATION TRANSPORT AND MAGNETIC FIELDS WHICH WILL LEAD TO THE MOST REALISTIC AND RESOLVED PREDICTIONS FOR THE EARLY UNIVERSE; 2. TO PREDICT THE OBSERVATIONAL FEATURES OF THE FIRST GALAXIES THROUGHOUT THE ELECTROMAGNETIC SPECTRUM ALLOWING FOR OPTIMAL EXTRACTION OF GALAXY AND DARK MATTER HALO PROPERTIES FROM THEIR PHOTOMETRY IMAGING AND SPECTRA; THE PROPOSED RESEARCH PLAN ADDRESSES A TIMELY AND RELEVANT ISSUE TO THEORETICALLY PREPARE FOR THE INTERPRETATION OF FUTURE OBSERVATIONS OF THE FIRST GALAXIES IN THE UNIVERSE. A SUITE OF ADAPTIVE MESH REFINEMENT SIMULATIONS WILL BE USED TO FOLLOW THE FORMATION AND EVOLUTION OF THOUSANDS OF GALAXIES OBSERVABLE WITH THE JAMES WEBB SPACE TELESCOPE (JWST) THAT WILL BE LAUNCHED DURING THE SECOND YEAR OF THIS PROJECT. THE SIMULATIONS WILL HAVE ALSO TRACKED THE FORMATION AND DEATH OF OVER 100 000 MASSIVE METAL-FREE STARS. CURRENTLY THERE IS A GAP OF TWO ORDERS OF MAGNITUDE IN STELLAR MASS BETWEEN THE SMALLEST OBSERVED Z>6 GALAXY AND THE LARGEST SIMULATED GALAXY FROM "FIRST PRINCIPLES" CAPTURING ITS ENTIRE STAR FORMATION HISTORY. THIS PROJECT WILL ELIMINATE THIS GAP BETWEEN SIMULATIONS AND OBSERVATIONS OF THE FIRST GALAXIES PROVIDING PREDICTIONS FOR NEXT-GENERATION OBSERVATIONS COMING ONLINE THROUGHOUT THE NEXT DECADE.THE PROPOSED ACTIVITIES PRESENT THE GRADUATE STUDENTS INVOLVED IN THE PROJECT WITH OPPORTUNITIES TO GAIN EXPERTISE IN NUMERICAL ALGORITHMS HIGH PERFORMANCE COMPUTING AND SOFTWARE ENGINEERING. WITH THIS EXPERIENCE THE STUDENTS WILL BE IN A POWERFUL POSITION TO FACE THE CHALLENGING JOB MARKET. THE COMPUTATIONAL TOOLS PRODUCED BY THIS PROJECT WILL BE MADE FREELY AVAILABLE AND INCORPORATED INTO THEIR RESPECTIVE FRAMEWORKS TO PRESERVE THEIR SUSTAINABILITY.