Introduction Definition and 860 Threads

Hi, my daughter saw my MTW copy on the desk and she asked me about the picture with the apple in front. To introduce her to the idea of gravitation as curved spacetime I answered like this: Consider you (A) and a your friend (B) at two different spots on a garden each with a firecracker. Take...

This is username Deep Sciences and joined this forum to share and explore information about the beauty of physics and science.

Hello, In the context of Legendre expansion with ##C_\ell## quantities, below the following formula which is the error on a ##C_\ell## : ##\sigma_(C_{\ell})=\sqrt{\frac{2}{(2 \ell+1)\Delta\ell}}\,C_{\ell}\quad(1)## where ##\Delta\ell## is the width of the multipoles bins used when computing...

Can anyone provide a good introductory reference to machine learning. Right now, I am interested in understanding the advantages and disadvantages of the various ML methods. I am not currently interested in detailed descriptions of their implementation. I am probably going to have to brush up...

Hello! I am a senior in high school who adores physics and hopes to pursue it further in college. I joined this forum because I haven't really found a community that likes physics as much as I do. Hopefully, this is the right place. Right now, I am currently building my knowledge of fluid...

Hello guys, I am a 22 years old french physics student. I am doing a master in Theoretical Physics and want to have a PHD. I love fundamental physics and this is what I want to do for the rest of my life. Because I am an idiot, I never really studied hard or listened during lecture so I have a...

Hi! Does anybody know if, and if so where, to find solutions for the textbook on elementary particle physics by David Griffith? I would like to compare my results to check if I am doing it alright. Thanks gluon

I'm a physicist familiar with QM, QFT and GR etc but I've never really sat down and learned astrophysics properly. Would Steven Weinberg's new book be considered a good advanced introduction or would people recommend another text. Half tempted to get it anyway to complete the Weinberg collection.

Hi! I have been looking at differential forms, manifolds and de Rham cohomology. Now I'm trying to figure out the connection from cohomology and equations of motions and topological field theory. Problem is that I am only looking at abelian field theories and I only find introductions into...

How much does the equivalent width of a line change by the introduction of 5% scattered light? We know the equivalent width is defined as We know the equivalent width is defined as $$W = \int_{-\infty}^{\infty} \bigg(\frac{1-F_{\nu}}{F_c}\bigg) \, d\nu$$ where ##F_{\nu}## represents the flux in...

Hello everyone! I'm glad I found this forum. I'm a student and studying to be a system analyst. Sometimes I need help with physics for homework and sometimes I have questions which interesting for me because I'm interesting in physics. So, I hope I'll find interesting threads for me :) Have a...

I am self-studying Ivan Niven's An Introduction to the Theory of Numbers. Unfortunately, I find myself stuck while doing the problems. With this in mind, I would like to ask whether anyone here has the solution manual for Niven's textbook. Hopefully a softcopy version is available? Thank you in...

Summary:: Good introductory book about Group Theory? Hi, I am looking for a good introductory book about Group Theory for physicists.

I don't really have any support material!

As a person who loves intense discussion and debate, having a decidedly short list of peers willing to engage in such a way over topics like math, science, and etcetera, can be discouraging. By turning to these forums, my ultimate goal is to finally participate in a different sort of...

Can anyone advise me on a good introductory website about (formal) logic? Preferably about logic in a broad sense.

Continue reading...

Continue reading...

Greetings fellow forum users! I'm a hungarian physicist specialised in geophysics, currently doing a Master's Degree in Space Research & Remote Sensing. I enjoy participating in science-related discussions, so finding this website was the highlight of my day. I hope you have a nice weekend, and...

Summary:: Linear algebra 1.Let a a fixed vector of the Euclidean space E, a is a fixed real number. Is there a set of all vectors from E for which (x, a) = d the linear subspace E / 2. Let nxn be a matrix A that is not degenerate. Prove that the characteristic polynomials f (λ) of the matrix A...

prove that $2+8{\sqrt{-5}}$ is unit and irreducible or not in $\mathbb Z+\mathbb Z{\sqrt{-5}}$.

prove that u(z+zw)={+1,-1,+w,-w,+w^2,-w^2}

Hello everyone. =) In honor of Pi Day I'm going to be explaining the very beginning of set theory (which I consider the beginning of university math) live on Twitch in about two hours (1 PM GMT). For those who do not know Twitch, it's a completely free streaming platform - you can come in and...

Can you recommend books for introduction physics without calculus.That is basic.

[url="https://www.physicsforums.com/insights/an-introduction-to-the-generation-of-mass-from-energy/"]Continue reading...

Hello! My name is Parker, but you can call me Apex. I don’t really mind either way. I’m an 8th grader that is interested in physics and astrophysics. My favorite author is Michio Kaku and he inspires me to learn more. I’ve read two books by him so far. I hope that through this website I can...

Hi, I am an undergraduate student in the 3rd sem, we have Lagrangian Mechanics in our course but I am unable to follow it properly. Can you please suggest me a book that will introduce me to Lagrangian and Hamiltonian Mechanics and slowly teach me how to do problems. I am beginner, so please...

Summary:: Pretty sure they have something to do with path integrals, or what not. But obviously it's hard to *search* for this stuff. Basically, I'm looking for a textbook, any textbook--physics, mathematics, etc.--that deals with integrals that look something like this (mistakes are mine): S...

Should i read Introduction to Calculus and Analysis by Courant? I have calculus background I want to study multivariable and single variable in rigorous way There is a lot of books in this subject like Spivak, apstoal,Courant,... . I am not sure what to choose

Although Stokes Theorem says that the line integral of a closed surface equals to zero why do we get a non-zero value out of this question 1.11 (and figure 1.33) in the Griffits Introduction to Eletrodynamics Book?

I have a copy of Griffiths Introduction to Elementary Particles (1st Edition) and was thinking of beginning to work through it. I was curious if anyone knows if this text is sufficiently up to date or if there have been any major developments in particle physics that would make it worth getting...

Hey, PF! I am currently studying Algebra and Trig, and was wondering what's a good book to use to get eased into the process of proving statements and theorems. I'm planning to use Basic Mathematics by Lang but the proofs in it have been a real hindrance to my progress. Even just simple proofs...

Summary: A short introduction to a antique calculator that I recently got I first know about this thing when I was chatting with @jedishrfu a couple months ago, and I was fascinated by it. It functions like a soroban but looks way cooler and easier to carry around. Also, it is a important...

I am writing an introduction to a first course in elementary number theory. The topics are linear Diophantine equations, modular arithmetic including FLT and Euler's Generalization, quadratic residues and Non - linear Diophantine equations. How can I write an introduction to this showing linkage...

I am writing an introduction to a first course in elementary number theory. The topics are linear Diophantine equations, modular arithmetic including FLT and Euler's Generalization, quadratic residues and Non - linear Diophantine equations. How can I write an introduction to this showing linkage...

Hi guys, My name is TheGreatOneAD. I'm a 9th grader who would like to pursue a Ph.D. in Astrophysics or Theoretical Cosmology later in life and is in deep love with physics. For me, Physics is love and Physics is life.

I'm not really sure where to put this. I came across this nice article on Medium. “The 5 Basic Statistics Concepts Data Scientists Need to Know” by George Seif https://link.medium.com/APtnCOapOV

I like science, which is obvious if I'm on this forum. I mostly like biology but I dabble a little in everything. I like answering questions people have in introductory biology and chemistry. For my own interests, I mostly read about cellular ion channels, but I also read about integral membrane...

I have project about cooling the room with ice and fan, I want introduction to type it in the report, any idea, thanks :smile:

I want to produce a resource that has a narrative and includes the following topics: Sets, logic and proofs, numbers (irrational, integers, rational, …), binomial theorem, geometric series, inequalities, define things like identity, polynomial, symmetry, sigma and product notation. It is in...

I want to produce a resource that has a narrative and includes the following topics: Sets, logic and proofs, numbers (irrational, integers, rational, …), binomial theorem, geometric series, inequalities, define things like identity, polynomial, symmetry, sigma and product notation. It is in aid...

Aloha, My name is Charli - I am a computer systems Engineer based in Hawaii working with Lockheed Martin. I end up with a lot of random questions about the projects I do in my spare time and came here to ask some of those questions. My questions are currently based in a small chemistry project...

I am not a physics graduate nor a student. I believe I am an enthusiastic learner. I will need lots of help from you all to reach my goal of decent science literacy.

Hello there. I've recently joined the community of "Physics Forums". My main aim was to learn more about the world of physics from the posts on various questions throughout this forum. I'm currently 16 years old, in High school and have been studying Basic physics for 2 years now. I frequently...

Can someone recommend me a textbook about Introduction to Physics (college level)? I would thank a lot.

Greg Bernhardt submitted a new blog post An Introduction to the Traditional Abacus of China and Japan Continue reading the Original Blog Post.

Hey there! This is Mayank Bhandare, from India. I am a recent graduate in Mechanical Engineering from the University of Mumbai. Though it's a strange switch as many would say, I am planning to pursue a career as a Theoretical Physicist/Cosmologist. I have a couple of entrances the next month...

Why would anyone like to intoduce a antibiotic gene in a bacteria if it will make it resistant to antibiotics which is not of any advantages to humans?

Hi! I am Bilal Rajab. I have a question regarding Quantum Physics. From where can we learn about Quantum Physics and what is its relation to Classical Physics? Why is there not one single Physics...? Thanks Regards, Bilal Rajab Abbasi

Here's a bit about myself (past stuff, present status, future hopes), though I might not go into enough detail to uniquely identify me: As far back as middle school, I'd say I was committed to studying physics. Although, now I'd say it's hard to commit from a decently-well-informed standpoint...