Introduction Definition and 851 Threads

Hello, I'm just an undergraduate student in their final year at university. I've never been good at mathematics so I want to pursue it as a hobby and a challenge to myself, starting from the basics! I have a few questions of my own floating in my head so you'll definitely see me sticking...

Prove this Proposition 1.2.6 v in Introduction to Real Analysis by Jiri Lebl Dear Everybody, I need some help with seeing if there are any logical leaps or errors in this proof. The theorem states: $A\subset\Bbb{R}$ and $A\ne\emptyset$ If $x<0$ and A is bounded below, then...

Hi, I’m 28 years old and live in Minnesota. Most of my knowledge about physics is self-taught. (I love knowledge but don’t tend to thrive too well in academic settings for a number of reasons. Kind of like how some people are spiritual but don’t care for organized religion). Anyway, thanks Greg...

Hi I'm Robbie, a uni student studying physics and mathematics. I hate experiments and I like theory. Also, I'm not passionate about physics, yet. I really enjoy investigating math maybe because it has a much lower barrier for discovery (and breadth) in comparison to physics. Anyways, I hope I...

If you're looking to get a serious but entertaining introduction to computer programming, I wholeheartedly recommend Anne, Andrew, and Genevieve's course, "Programming Fundamentals". https://www.coursera.org/learn/programming-fundamentals I know one of the instructors from my days at Penn, and...

Hello, I am excited to be a part of this forum which has helped me during my undergraduate studies. I am study for a double major in computer science and physics and I am passionate about helping science stay accessible and relevant in our changing digital age. I am working on an open source...

Hello! I'm just starting out studying physics at university level, so I hope I can have interesting conversations here! Cheers, Merlin

Okay. Got this out of the way.

Hello, I'm new here and am hoping to give and receive as much information, such as facts, ideas, theories, suggestions. I love those questions that just make you really think. I look forward to exploring the unknown world with everyone here!

Hello Physics Forums! Just made my account, and here I am to introduce myself. I've only taken one physics class, but I loved it. I also seriously enjoy watching Youtube videos about science (e.g. Shoddycast), and that as well as stories like The Martian have driven me to take a more...

Hi it's asking for a Question, but I was sent here to introduce myself, so I'll do that. I'm in Southport in the UK and despite not having a University Education I've spent a lot of time.. too much, some say studying Quantum theory and Cosmology. I'm going to use a term that's probably not...

Hi everybody of the physics forms verse ! I'm Joy Patel a high school student . I like physics and maths . Cheers !

hey guys i am fares i am from Egypt and i adore physics psychology and philosophy i am 13 and i have allot of questions about physics i wish you answer it in the future ! bye

I am reader Andrew Browder's book: "Mathematical Analysis: An Introduction" ... ... I am currently reading Chapter 8: Differentiable Maps and am specifically focused on Section 8.2 Differentials ... I need some help in fully understanding Proposition 8.12 and the notes leading up to it ... ...

Hi. I'm Forrest Guyton. I'm a Senior Physics major at RPI. I've been reading a lot of discussions on physics forums for years but I've never actually "joined". I'm finding that as I'm getting good at math and comfortable with a lot of the formalisms we use in physics. I'm starting to be plagued...

Hello, I'm a college student in Philippines currently taking up Computer Engineering. I hope you don't mind me posting questions every now and then when I'm confused about a certain lesson. I'll try to help every now and then if there are questions that I can answer myself

New member here, who decided four years ago to look into quantum gravity. My original intentions were pure: really, how hard could quantum gravity be? My current intentions are: to empathize with those who have approached this subject, spent hours, days, months pulling their hair out, yet...

I want to pursue the sciences but I got no green. So I joined the BreakthroughJuniorChallenge in the hopes of winning! I would appreciate it if someone as knowledgeable as the people on this forum could comment and share my video submission. This is the link: It's also fine if you guys just...

I'm learning science 101, much from the internet. Realized that I can't trust it all. So found this site and thought I'd check it out and see if you guys will be able to help learn more, and verify info. Sorry if I'm all questions, and no answers for a while, I did say I'm just now learning from...

Hi everybody! Nice to meet you all. You can call me Luna. I am kind of a Mad Scientist girl who is finishing Med School, but with a ton of scientific hobbies. From fungus colecction to Quantum Mechanics! Lately, I'm enrolling in some subjects and online courses, especially about physics. I hope...

Just wanted to say hi to all. As the average 71 year old truck driver I have a lot of time on my hands so my mind tends to wander. As I get deep in thought there tends to be cave ins. I will share some of the debris here. I am coming from a typical high school education but luckily, as mentioned...

Urs Schreiber submitted a new PF Insights post Introduction to Perturbative Quantum Field Theory Continue reading the Original PF Insights Post.

Hi everyone. I am Nathan and I'm studying Chemistry in the University. Nice to meet you all.

Homework Statement In the image, as the first chapter of thermodynamics class, I understand all things in the answer except the highlighted part (lower bottom of the image). It is not directly related to thermodynamics but about the area ratio of the two ends of the tube, but I do not...

My name is Douglas and I live in the south of Brazil. I am a physics teacher. It's a pleasure to be with you. Good luck to everyone!

Hello, my name is Carmine. I am a 13 year old male who currently lives in southern Wisconsin. In the future I hope to live in Morocco or possibly Switzerland. As a 13 year old, I do enjoy physics but my knowledge of technical physics is limited and spend most of my time learning mathematics or...

I am a Rutgers and NJIT-educated professor of Physics, now under contract to Farmingdale State College and Nassau Community College, with other recent assignments at LIU Post and the BOCES Regional STEM High School. I embarked on doctoral-level studies in 2010 at Stony Brook University in their...

Heyyy I am new to this forum even though I have been browsing it from almost the middle of my IB year 1. It is really fun browsing this, and the discussions are very helpful, too! Now that I have problems with my Physics EE I have decided to join this forum. I hope that I will get helped and I...

Hello, my name is Thorbjørn and am an aficionado of physics. Currently still in high school (homeschool) I am looking for others around the same age as myself (16) to create a sort of younguns physics group for questions and advice given by people who understand the struggle of not having...

I am looking forward to have thought oriented imaginative interaction. I have been using math stack exchange which even though provides very good answers does not value varied opinions and freedom of thought provoking questions. And it conflicts my view on mathematics that more analytic oriented...

Homework Statement construct ψ(x,t)^(2) where ψ(x,t) = 1/5(3ψ_0(x)e^(-iE_0t/ħ)+4ψ_1(x)e^(-iE_1t/ħ). I know we square it but we have to find E_0 and E_1 and put it in. Homework Equations E_n = (ħ^(2)k_n^(2))/2m = (n^(2)π^(2)ħ^(2))/2ma^(2) The Attempt at a Solution E_0 = 0 and E_(1) =...

How are you? I am largely ok but kind of stressed.

Hello those who are reading! I have just graduated with my undergraduate Bachelors degree in Civil Engineering with a 3.4 GPA. I currently work for a large civil construction company as a field engineer. I have written and published a Children's book about engineering called "Roxy the Fox and...

Hi, I'm Bal from the Philippines. Currently taking BS Applied Physics (computational physics) Research interests includes: Complex Systems, Chaos Theory, Population Dynamics, Image Processing, Simulations Other Interests: Critical and Cultural Theories(Humanities), Films Nice to meet you...

Hi! My name is Joan and I am new here. I study psychology so I am far from having an adequate understanding of physics or mathematics. I am just interested in cosmology and I often have many questions to ask around current theories and nobody to answer them. So I am here to learn and grow, nice...

Hello folks, I'm a student of electrical engineering and also a physics enthusiast. Have some topics I'm interested in and finally got enough nagging questions to create an account.

What is your opinion about "Introduction to Conformal Field Theory-With Applications to String Theory" by Blumenhagen, Plauschinn Springer (2009)? <Moderator's note: type setting edited>

I am a former senior flight surgeon at CCAFS and Kennedy Space Center. I have been privileged to speak with many fantastic engineers, scientists, and astronauts. Many times they have had to stop a discussion to explain to me items of interest, and I am always interested in learning something I...

Hello, physics forum, I'm Zaya Bell, science(including psychology) lover. Just liked working together with people, so will love to join in conversations.

Hi all. I am an undergraduate student studying physics at MIT. I'm hoping to answer as many questions as I can and getting my questions answered as well. I realized I enjoyed answering physics questions and am hoping to be of use to the members of this community. Regards

I am a retired man, who has always wanted to be a Physicist. I have no credentials, and am not qualified to comment on anything, but I enjoy having studied Physics some 43 years ago, and am only slightly behind what was current then. I have engaged in discussions on Quora, and in many other...

Hello, I am Sameer, currently undergoing the masters' program in Microsystems Engineering. I am a big fan of fabrication technology, and stumbled by this forum due to a few QnAs regarding sputter deposition. Hope to be here for a while. :) Cheers, Sameer.

I rarely do forum introductions but I'll do my best. My name's Tom, and I am a science hobbyist. I enjoy trying to find answers to some of the most difficult-to-answer questions/science fields that are still relatively immature (neuroscience for example). I am definitely not well-versed in the...

Does anyone have any good recommendations for some introductory books on nuclear fusion that I can read from my phone?

hi i am a mom with a kid whos into physics

Hi guys! I just made an account here after using this website for a good portion of high school physics. I'm currently taking physics 12 and is that it for the introduction? Thanks!

Wanted to be a cricketer till my 8th-grade teacher taught me Atom and Structure of atom. Passion arose that day led me to go to India's best engineering school-IIT Kgp. Got placed as a coder but my love for Physics is too much. Have started my own channel on Youtube -...

I work at the Kampala Institute of Technology in Kampala, Kampala, Uganda. We are doing serious work here, but often due to our lack in sound quality education we have many questions. Therefore I have sought a website such as this. Currently I am studying the Ward-Takahashi conjectures and off...

An introductory course in rigid body dynamics for mechanical engineers introduces kinematics, then kinetis and then work/energy. Can I ask for your opinions? Is this necessary? I can see the need to discuss work/energy to understand Hamilton's Principle. But is there any reason to labor...

Lightcone gauge is ##X^u=\tau=1/\sqrt{2}(X^0+X^{D-1})## (1) The mode expansions are: My book says 'it is possible to solve for one of the oscillators in terms of all the others' with this relation. What is a oscillator? Is this any of the ##X^{D}## coordinates, what exactly does ##n##...