01:750:341
Rutgers University
Fall 2024

Prof. Matthew Buckley
Class meetings: Tuesday/Friday 12:10-1:30 
Building: SEC-203
Office hours: Serin W329 time Wednesday 10-11, Thursday 3-4

Email: mbuckley@physics.rutgers.edu

Please use your Rutgers email for all course communication.

Course overview

Astrophysics is the application of physical principles to astronomical systems. In Physics 341 and 342 you will learn how to use gravity, electromagnetism, and atomic, nuclear, and gas physics to understand planets, stars, galaxies, dark matter, and the Universe as a whole. Gravity is the dominant force in many astronomical systems, and it will be our focus in Physics 341.

Some astrophysical systems are described by equations that are fairly easy to solve, and we will certainly study them. Many other systems cannot be solved exactly, but we can often use physical insight and approximate calculations to understand the salient features of a system without sweating the details. One goal of the course is to develop that skill. As you will see, it will take us very far – through the whole Universe, in fact! Another goal is to learn about recent advances in astrophysics, a very dynamic field of research.

Topics

Here is the anticipated list of topics and applications we will examine this semester:

  • celestial mechanics, gravitational 1-body problem - supermassive black holes

  • gravitational 2-body problem - binary stars, extrasolar planets

  • tidal forces

  • gravitational 3-body problem - Lagrange points, orbital resonances

  • spiral galaxies, rotational dynamics

  • elliptical galaxies, virial equilibrium

  • gravitational lensing

  • special and general relativity - black holes, gravitational waves

  • relativistic cosmology - expanding universe

The detailed class schedule is below, including reading assignments and problem set due dates.

Learning goals

Here are specific learning goals for this course:

  • Understand physical principles and their application to astronomical systems

    • Specifically, understand how to use gravity to infer mass from motion

  • Become skilled at estimation techniques, including dimensional analysis, scaling relations, and Taylor series expansions

  • Learn about exciting developments in astrophysics

These support two of the overall learning goals for the Department of Physics and Astronomy:

  • Top 25% of our Physics majors demonstrate mastery of basic Physics and the ability to solve essential problems appropriate for beginning graduate study in Physics.

  • All Physics majors demonstrate knowledge of fundamental Physics principles and are able to quantitatively analyze a broad spectrum of problems presented in a range of undergraduate Physics courses.

Course structure

This class will meet in person (Tu/F 12:10-1:30 room SEC-203). Office hours will be offered in person (Serin W329, times TBA). Office hours may be offered on zoom if conditions warrant.

Students with disabilities requesting accommodations must follow the procedures outlined at https://ods.rutgers.edu/students/getting-registered. Full disability policies and procedures are at https://ods.rutgers.edu/.

Prerequisites

Prerequisites for this class include an introductory course on mechanics, and Calculus II. I will briefly review physical principles as we need them, but assume that you have seen them before. I will also assume familiarity with vector calculus. Some of the assignments may involve a bit of computation that can be done with programs like Microsoft Excel, Google Sheets, Maple, Matlab, python, or Mathematica.

Course materials

Lectures will be based on the textbook Principles of Astrophysics: Using Gravity and Stellar Physics to Explore the Cosmos (ISBN 978-1-4614-9235-1), which was written for this course. Optional, supplementary information can be found in An Introduction to Modern Astrophysics by Bradley W. Carroll and Dale A. Ostlie (affectionately known as the Big Orange Book; ISBN 978-1-1084-2216-1).

We will have interactive poll questions in class using the online polling system Slido, which you can access with a device you already have (laptop, phone, or tablet).

Assessment

We will have weekly homework assignments due at the beginning of class on Fridays. To submit the homework, please scan your completed problem set and upload a pdf to Canvas.  Show your work. You will not receive full credit if you do not show your work. I am always looking for the reasoning behind the answer.

In working on the problems, you are encouraged to talk with others in the class, but you must write up your own solution, and you must list your collaborators on your write-up. You are allowed to consult outside reference material (which must be cited), but you may not examine homeworks or solutions from previous years of Physics 341/342 or other similar courses online, nor are you allowed to post homework or exam questions online. You may not use Large Language Models (LLMs, colloquially known as AI, such as ChatGPT, Claud, etc). No late homeworks will be accepted without prior permission from the instructor! The two lowest homework scores will be dropped in calculating the course score. That means you can miss or skip two homeworks for any reason and still get a perfect score; however, experience has shown that it is typically better for your grade to turn in all of them and have the two lowest scores dropped.

There will be one midterm exam in class, and a final exam during the scheduled final exam period. Details about the exams will be provided as the semester progresses.

Always show your work. You will not receive full credit if you do not show your work. In general, I am not looking for a specific answer; rather, I am always looking for the reasoning behind the answer. Also, please submit your best work (i.e., take the time to write out your solutions clearly and carefully).

Your course score will be calculated as follows:

  • 60% problem sets

  • 20% midterm exam

  • 20% final exam

A course grade of 90% or higher will guarantee you an A.

Policy on LLMs/"AI"

Large Language Models (LLMs, sometimes called Artificial Intelligence - AI) are not substitutes for active learning. As I will discuss in class, current iterations of LLMs will often fail to provide accurate answers to the type of homework assigned in this class, and the mode of failure is subtle and difficult to detect if you don't already know the correct answer. Presumably you are taking this course to learn the material: using LLMs will actively impede that goal. If you have questions and need help with the material and the assignments, please reach out to me.

I am also aware that programs that claim to detect the use of LLMs in submitted assignments are inaccurate, and that such detection is likely impossible.

For these reasons, you are not to use LLMs to answer the homework problems in this course. I will also not run your homework through an automated detection algorithm. A clear violation of this policy will result in a zero on the assignment.

Policies

  • Changes: The course schedule and guidelines are subject to change. I will communicate any changes promptly and clearly. Still, it is your responsibility to make yourself aware of any and all changes by attending class and maintaining communication with me.

  • Absences: Students are expected to attend all classes; if you expect to miss one or two classes, please use the University absence reporting website to indicate the date and reason for your absence. An email is automatically sent to your instructors.

    • If you have been told to quarantine, or are experiencing symptoms of any transmissible disease, please do not attend in-person class meetings. Contact me to make arrangements for handling such absences.

Resources for student success

The faculty and staff at Rutgers are committed to your success. Students who are successful tend to seek out resources that enable them to excel academically, maintain their health and wellness, prepare for future careers, navigate college life and finances, and connect with the RU community. Helpful resources include the Rutgers Learning Centers and school-based advising (for SAS, SOE., SEBS, and RBS.). Additional resources that can help you succeed and connect with the Rutgers community can be found at https://success.rutgers.edu.

Please visit the Rutgers Student Tech Guide for resources available to all students. If you do not have the appropriate technology for financial reasons, please email the Dean of Students (deanofstudents@echo.rutgers.edu) for assistance. If you are facing other financial hardships please visit the Office of Financial Aid.

 

Academic integrity

Rutgers University takes academic dishonesty very seriously. By enrolling in this course, you assume responsibility for familiarizing yourself with theAcademic Integrity Policy and the possible penalties (including suspension and expulsion) for violating the policy. As per the policy, all suspected violations will be reported to the Office of Student Conduct. Academic dishonesty includes (but is not limited to):

  • Cheating

  • Plagiarism

  • Aiding others in committing a violation or allowing others to use your work

  • Failure to cite sources correctly

  • Fabrication

  • Using another person’s ideas or words without attribution–re-using a previous assignment

  • Unauthorized collaboration

  • Sabotaging another student’s work

If in doubt, please contact me. Also review the Academic Integrity Policy. and Academic Integrity Resources for Students.

Use of external website resources (such as Chegg.com or others) to obtain solutions to homework assignments or exams is cheating and a violation of the University Academic Integrity policy. Cheating in the course may result in grade penalties, disciplinary sanctions or educational sanctions. Posting homework assignments or exams to external sites without the instructor's permission may be a violation of copyright and may constitute the facilitation of dishonesty, which may result in the same penalties as cheating.

The Rutgers honor pledge will be included on all major assignments for you to sign: On my honor, I have neither received nor given any unauthorized assistance on this examination/assignment.

Almost all original work is the intellectual property of its authors. This includes not just books and articles, but the syllabi, lectures, slides, recordings, course materials, presentations, homework problems, exams, and other materials used in this course, in either printed or electronic form. You may not copy this work, post it online, or disseminate it in any way without the explicit permission of the instructor. Respect for an author’s efforts and intellectual property rights is an important value that members of the university community are expected to take seriously.

 

Student Wellness Services

The university provides a number of resources to support your physical and mental well-being. I list several valuable resources here and encourage you to contact me for more guidance about university resources.

  • Report a Bias Incident If you experience or witness an act of bias or hate, report it to someone in authority. You may file a report online and you will be contacted within 24 hours. The bias reporting page is here.
    Bias is defined by the University as an act, verbal, written, physical, psychological, that threatens, or harms a person or group on the basis of race, religion, color, sex, age, sexual orientation, gender identity or expression, national origin, ancestry, disability, marital status, civil union status, domestic partnership status, atypical heredity or cellular blood trait, military service or veteran status.
    Click here to report a bias incident

  • Counseling, ADAP & Psychiatric Services (CAPS)
    (848) 932-7884 / 17 Senior Street, New Brunswick, NJ 08901, http://health.rutgers.edu/medical-counseling-services/counseling/
    CAPS is a University mental health support service that includes counseling, alcohol and other drug assistance, and psychiatric services staffed by a team of professionals within Rutgers Health services to support students’ efforts to succeed at Rutgers University. CAPS offers a variety of services that include: individual therapy, group therapy and workshops, crisis intervention, referral to specialists in the community, and consultation and collaboration with campus partners.
    Crisis Intervention: http://health.rutgers.edu/medical-counseling-services/counseling/crisis-intervention/
    Links to an external site.    Report a Concern: http://health.rutgers.edu/do-something-to-help/

  • Violence Prevention & Victim Assistance (VPVA)
    (848) 932-1181 / 3 Bartlett Street, New Brunswick, NJ 08901, http://vpva.rutgers.edu/
    .    The Office for Violence Prevention and Victim Assistance provides confidential crisis intervention, counseling and advocacy for victims of sexual and relationship violence and stalking to students, staff and faculty. To reach staff during office hours when the university is open or to reach an advocate after hours, call 848-932-1181.

  • Disability Services
    (848) 445-6800 / Lucy Stone Hall, Suite A145, Livingston Campus, 54 Joyce Kilmer Avenue, Piscataway, NJ 08854, https://ods.rutgers.edu/ Rutgers University welcomes students with disabilities into all of the University's educational programs. In order to receive consideration for reasonable accommodations, a student with a disability must contact the appropriate disability services office at the campus where you are officially enrolled, participate in an intake interview, and provide documentation: https://ods.rutgers.edu/students/documentation-guidelines. If the documentation supports your request for reasonable accommodations, your campus’s disability services office will provide you with a Letter of Accommodations. Please share this letter with your instructors and discuss the accommodations with them as early in your courses as possible. To begin this process, please complete the Registration form on the ODS web site at: https://ods.rutgers.edu/students/registration-form.