theoretical physics Definition and Topics - 100 Discussions

Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experimental tools to probe these phenomena.
The advancement of science generally depends on the interplay between experimental studies and theory. In some cases, theoretical physics adheres to standards of mathematical rigour while giving little weight to experiments and observations. For example, while developing special relativity, Albert Einstein was concerned with the Lorentz transformation which left Maxwell's equations invariant, but was apparently uninterested in the Michelson–Morley experiment on Earth's drift through a luminiferous aether. Conversely, Einstein was awarded the Nobel Prize for explaining the photoelectric effect, previously an experimental result lacking a theoretical formulation.

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  1. P

    Job Skills Any industry job for physics grads requiring no programming?

    Hi all, my question is as title. I am a fourth year PhD student in US and planning to graduate early to get in industry or community college. I major in high energy theory, and I have no coding/simulation skills at all (not interested at all). Thus, my situation is that professionally I have...
  2. S

    Nobel laureates for and against string theory?

    According to Michio Kaku, Nobel laureates have taken both sides towards string theory since some of them accept it and some of them reject it, as he says here ( “Kaku also explains the intense controversy swirling around this theory, with...
  3. W

    How to study Mathematics for Theoretical Physics

    I have a B.S in Mathematics, but wish to pursue Theoretical Physics. I still have a great deal of undergraduate Physics coursework to take before I can apply to graduate programs. My question has to do with the Mathematics that is crucial in order to do Theoretical Physics. Is the mathematics...
  4. andrew0310

    Physics What is it like to do theoretical physics research?

    Hello everybody, I am an undergraduate student studying computer science and I love it, especially Artificial Intelligence. I'm a curious person, so there are a lot of things that I find intriguing. But I sometimes wonder if a physics career would be more interesting, not because I don't like...
  5. F

    From software development to physics PhD

    Hi there, Last June 2019 I graduated with a First class honors in Theoretical physics from one of the Top Unis in the UK. Then I started working for a company (of good prestige) as a software engineer full time. However, a few months in, I decided to apply for Masters and start a side project...
  6. N

    Math Switching from Electrical Engineering to Theoretical Physics

    Hi all, I'm going to graduate this May with a degree in Electrical Engineering. While I've done pretty well, my passion was never in EE and I'd like to aim for graduate school in Computational Neuroscience. When I look at the background and methodology employed by many favorite (current)...
  7. warhammer

    I Top Theoretical Physicists

    In respect to the above question, I also have a follow up question. Is progress in Theoretical Physics somewhat slow currently as compared to Experimental Physics?
  8. M

    Potential functions for separation and isochronic gauges

    Most potentials in physics are expressed as a radius or another geometric norm/gauge. I am looking to understand the significance of the choice of potential functions for force/pressure separation in harmonic analysis before this creates a topology. To my understanding this is the decision of...
  9. starstruck_

    Determine the singularity type of the given function (Theo. Phys)

    NOTE: Was not sure where to post this as it is a math question, but a part of my "Theoretical Physics" course. I have no idea where to start this and am probably doing this mathematically incorrect. given the function f(z) = cos(z+1/z) there should exist a singular point at z=0 as at z = 0...
  10. P

    Physics How risky is doing a PhD in theoretical Physics?

    Hello everyone! Apologies if this question has been asked and answered before, please feel free to direct me to that post and delete this one, if needed and if it has been asked before and this post is, hence, redundant. I looked up some of the earlier posts such as...
  11. M

    Programs Module Choice advice for a theoretical physics degree (Durham)

    I'm starting at Durham on the 29th of September and I need to get my module choices sorted. I have the choice between 40 credits of maths modules designed for scientists, and 40 credits of maths modules done by regular maths students. They say that you should only do the regular maths modules if...
  12. cordless03

    A High-Energy biophysics?

    Are there any ways particle physics can impact biology? Specifically, being able to use methods from theoretical physics to study biological systems (possible physiology related).
  13. STasnim12357

    Schools How good is the Theoretical Physics MSc course at Queen Mary?

    Hello am currently an undergraduate student. My major is CSE. But I am very much interested to do my masters and then PhD in theoretical physics/mathematical physics. Is there any university that admits CS graduates for these courses? I have looked up some universities that offer these courses...
  14. M

    What avenue of physics can a scientist in the Star Wars galaxy study?

    What I’m looking for is some new avenue of physics for a scientist in the Star Wars galaxy to be studying. They probably know what dark matter and dark energy are since Starkiller Base is powered by it. I’m sure they know about how the universe began, why it’s expanding and what it’s fate is...
  15. Replusz

    Other Looking for ideas for new theory

    Dear All, I am a second year Natural Sciences (the course incorporating the Physics courses) student at the University of Cambridge. I definitely want to specialize in Theoretical Physics next year, but the years spent at University, and the time in the vacations between terms, seems so long...
  16. J

    Courses Physics and Abstract Algebra

    My university offers two different two-semester sequences for learning abstract algebra, and I can't decide which one would be better for me, a physics major. Here are the two sequences and their course descriptions, copied and pasted from the university website: Algebra 1: Theory of groups...
  17. G

    Schools From theoretical physics master to 2nd year grad school

    I would like to ask if anyone has been admitted to a graduate school(US) straight to 2nd year after a theoretical masters MSc degree in the UK. I am asking because I would really like to study in the US, preferably on top universities but I don't want to waste another year taking essentially...
  18. G

    Schools Theoretical physics university climbing

    I'm a 4th year MPhys student currently finishing my undergrad. I will be attending a theoretical masters course next year at Kings. I have been declined by Imperial and Cambridge so I have started to get a little worried about my future. Even though I have been declined this year, is there any...
  19. L

    Job Skills Theoretical vs Experimental Physics -- which is more glamorous?

    I am worried that I am passionate about physics and yearn for a career in physics(through theoretical physics), and by a career I mean a placement in a prestigious institute and then be part of leading physics, but would that require sacrificing my entire 20s and even 30s or can I can get all...
  20. S

    B Black holes and the Big Rip

    According to the Big rip theory if Black holes tear apart after a very long time, then according to the theory of relativity an object that reaches the event horizon should see time passing infinitelty and by the time the object was swallowed wouldn't the black hole not exist anymore because of...
  21. K

    Chemistry Chemistry textbook for Physicists

    Hello Being a professional physicist(Quantum field theory and HS theory) I'd like to learn chemistry for some reasons. I've already tried to find a nice Chemistry textbook but failed to find physicist friendly one. My last class on chemistry was in highschool like 11 years ago already, so my...
  22. George Keeling

    News What do theoretical physicists do?

    I took great comfort reading a New Scientist article on the Perimeter Institute, Canada where top theoretical physicists pass the day. They asked four how they get through the day. Two replies gave me great comfort: Asimina Arvanitaki I spend most of my time being confused about things and...
  23. S

    I Interpreting SM Lagrangian "differential particle" terms

    The Standard Model Lagrangian contains terms like these: ##-\partial_\mu \phi^+ \partial_\mu\phi^-## ##-\frac{1}{2}\partial_\nu Z^0_\mu\partial_\nu Z^0_\mu## ##-igc_w\partial_\nu Z^0(W^+_\mu W^-_\nu-W^+_\nu W^-_\mu)## How should one interpret the "derivative particle fields" like...
  24. LilyWillows

    Physics Employability with a degree in theoretical physics vs physics

    Hi! I'm currently in my second year of a five year integrated masters degree in physics. When applying, I chose to study just plain physics as I didn't really know what I wanted to do and I didn't want to limit my options. However, for the past year and a half, and honestly before that too, I've...
  25. Brian Leist

    Admissions How to enter theoretical physics with astronomy background?

    Hi all, I am interested in advancing my education in theoretical physics, specifically topics concerning quantum field theories and quantum gravity. However, I have a somewhat rocky background as an early undergrad and while my Master's degree was achieved with great success in the classroom...
  26. astroman707

    Courses Academic Preparation for gravitational wave careers?

    If someone wanted to pursue a career in gravitional wave physics, and work at places like LIGO, studying astrophysical objects such as black holes and neutron stars, etc. What are some key courses/skills that person should take/learn as an undergraduate, and graduate student?
  27. astroman707

    Programs Difference between an astronomy and astrophysics PhD?

    Is there really much of a difference between an astronomy PhD and an astrophysics PhD? There seems to be a lot of overlap in the fields, and it seems that both can qualify you for many of the same careers, it just depends on the PhD focus. For an example, I'm very interested in almost all areas...
  28. A

    I How was our universe created?

    Could the universe have been created by the collision of two older universes with the same dimensions? Could the expansion we observe be caused by these two universes still merging like boubbles coming together and the resulting increase of gas makes the film grow larger?
  29. Y

    Courses Should I take advanced courses as a physics undergraduate?

    I am a third year undergraduate physics student with some interest in theoretical physics. This term I want to learn General Relativity or Group Theory, but they are all hard, time-consuming courses. If I don't take them, I can explore broader areas of physics to make a decision on what I will...
  30. astroman707

    What math is used the most in cosmology/astrophysics?

    Considering one is taking all the required math courses for a typical physics degree, what math electives are most crucial to the field of cosmology/theoretical astrophysics? Also, is it true that mathematical modeling courses(discrete and dynamical modeling across physics) are more important to...