Theoretical Definition and 999 Threads

This is just for fun so don't take it too seriously... So I've read about particle beam weapons and as far as I understand its simply a concentrated beam of particles ie electrons emitted towards an object. I'm pretty sure I'm missing a big piece here when I say it (it just sound too easy) but...

Hi. I'm taking a look at this problem: And my doubt is with step 2 when he calculates the torque. He just says it is Fd. But...why? F only has a component which effectivly does torque. Thanks

My resident theoretical physicist, who I love dearly, is often very distraught. He describes his days of wracking his brains as painful, unproductive, and, at worst, a tedious backtrack through a bunch of stuff that he got wrong and must redo or unthink. Please help me to understand what he...

I'm about to go into my final(3rd) year of a maths BSc in the UK at Warwick university, and am currently looking at what options I'd like to take given that I'm hoping to go down the path into theoretical physics academia. I currently hold offers for Imperial College's "Quantum Fields and...

I m first year in theoretical mathematics (graduate study), but I am very interested in theoretical physics, I have some knowledge in physics, general knowledge in mechanics and thermodinamics, electrodynamics, optics, waves, basics in quantum theory, but I am very interested in elementary...

Homework Statement Calculate the theoretical lattice energy for MgF2 (Born-Landé equation) Ionic radius Mg+2 (coordination number 6) = 86 pm Ionic radius F- (coordination number 3) = 116 pm Madelung constant = 2.408 n = 7 Homework Equations The Attempt at a Solution I'm...

Homework Statement I need to determine theoretical vs actual range of a projectile; but first I must determine initial velocity. The projectile was launched from 1 meter high, at 0° with respect to the horizontal, so I shot it horizontally. The ball landed at a distance of 2.97 meters. My...

Hello all, I was just wondering if anyone could give me links to any websites that allow anyone to post their own papers. My apologies if I seem like a 'newbie', as I have not before posted a paper online. Any helpful responses are welcomed, thank you

What is the theoretical highest electric charge possible for an object wihout breaking it? What about charging a piece of PVC to trillions of volt, or trillions times that, or even more. Is it a limit how high the charge can be? Vidar

I look around the internet and there are theories about a lot of different aspects of physics such as various alternative theories on gravitation from GR, M-Theory, Quantum Theory. My question is, if math is used in physics to make sense of the world we see, and a lot of mathematical equations...

I'm not interested in becoming a theoretical physicist, that would be ridiculous, but I am curious to know how many TP are there, how many PHD degrees are awarded each year, how many applicants are there for a PHD per year and how many applicants are there for a masters in theoretical physicists...

Evening forum, I'd like to pursue a doctoral degree in theoretical physics. What sorts of jobs can one get in this field? Where would I work — strictly at a University, or at a lab, private company, etc? Any information about theoretical physics careers is appreciated. Thanks for your...

Hello, thank you for taking a look at this thread. Here is my dilemma, I can chose 30 credits from various math and physics courses (each worth 10) for my second year, but I've decided to do maths as the rest of my modules are all physics but there are so many I have no idea what maths modules...

Homework Statement I require the a means to theoretically calculate the spring constant of a hollow tube. Essentially, I need to find the diameter of the glass pipette which will have a spring constant of 100 Newtons/metre. If someone could point me towards relevant information on...

Hi. I am a math major that got started late. I started taking prerequisites during my sophomore year (which I'm finishing this year). I'll be taking some courses in algebra and analysis next year. There are some courses that can fulfill my major requirements, but some are theoretical and some...

Homework Statement Let f: A --> B be an injection and suppose that the set A is countably infinite; how can I prove that there is an injection from B to A if and only if B is countably infinite? Also, if we would suppose that A is uncountable, can B be countable? Homework Equations...

Theoretical, Experimental, Simulation, and... end of story? I know that this question cannot be answered with any absolute authority, but I'd still like to hear some speculation. Can there be a next frontier in the tools of science? Previously, we had experiments and theory. Later...

Hey all, I'm looking to apply for gradschool in the US at the end of this year and I'm currently struggling to figure something out I was hoping someone here might be able to assist me with. I intend to apply to the top 10-15 schools, but given the cost of applications, for universities...

I am still in middle school, just getting inducted in the NJHS and hoping to get into the IB program. I really what to get into a career in Theoretical Physics, is there anything i can do to help make my dreams of becoming a Theoretical Physicist a reality? Anything would help...

Need urgent help with a manufacturing problem. Our company built a product that is testing in spec for propionic acid and ammonia, but out of spec for pH. Desperate for this answer. The total product build is 24166.246 KG. The amount of propionic acid added is 15949.723 KG, which puts...

Hi, I was wondering what the scope is these days to do a PhD in theoretical physics, but without delving into string theory? Is the world of theoretical physics still very much dominanated by string theory, or can young physicists go down alternative routes? I seem to remember that some years...

Hi, I'll be starting next week a 6 months internship, and I'll be working on quantum cosmology, roughly. I have been studying physics for 5 years now, and mostly interested in theoretical things for 4 years (from my first lectures of electromagnetism to conformal field theory), but...

How the hell do you prove that the components of a vector w.r.t. a given basis are unique? I have literally no idea how to begin! It's just that with these theoretical problems there's no straightforward starting point!

Hey everyone If you want the concise version, skip over the bit in italics. First I'll quickly introduce myself. I am an undergraduate student, studying physics. I have been reading these forums for some time now (mostly just re-reading the stickies to be honest). In Australia, the first...

Hello! I am currently a sophomore in undergrad, majoring in Physics. I haven't been exposed to any computer languages, such as C++, and I am wondering if it necessary for me to know it? My major's requirement doesn't require it, but many of my physicist friends seem to recommend me take it. So...

Besides having the best academic record and publications, what else can one do to improve his chances to be accepted to this prestige club? Just a dream... :-(

Hello! I'm now finishing my final year of high school and preparing for university. I've applied to England to Imperial College, UCL, King's College, Queen Mary and Edinburgh all for a physics w/ theoretical physics or simply theoretical physics Msci in four years and planning to do a PhD...

I didn't know how to word it other than that. If astrophysics is all theoretical, then I should have worded it better, but even then I am not interested in cosmology, only in how things work, and I was wondering if this even makes sense. I have thought about it, and all I really know is I have a...

Orifice problem I've been given a list of quantities Pipe before orifice head = 255mm Diameter = 31.75mm Pipe after orifice head = 230mm Diameter= 20mm Time for 10litres to fill in collection tank 67.09seconds Assuming g= 9.81 and density = 1000 from the experiment difference in...

I am probably in the same boat as a bunch of people. My father passed away and had a ton of texts. He was a PhD/expert in Heat Transfer, Fluid dynamics and Nuclear Engineering. There are some good theoretical engineering,physics,math books from the 30's 40's and 50's, some of which might...

About a year and a half ago, I fell in love with mathematics, physics, and our universe. I had dropped out of High School when I was 15 (grade 10) and wasted a year outside of school. During this time I started indulging in marijuana and alcohol. Also, ironically, it was during this year that I...

Hey u guys. Say I'm an undergraduate wanting to be a physicist. Not just any physicist, but a theoretical physicist. Say that I'm already planning on taking all of the "Mathematical methods for Physics" courses offered at my university, but now I want more of some math action. Which subjects...

First, let me apologize for my bad English, it's not my native language. Most areas of math for me aren't really an issue. I'm actually quite good at it. But there's one thing I absolutely despise and also something I'm very bad at: geometry. I was planning on studying theoretical physics...

Is there a theoretical upper bound for the density of matter? Given a proton (already almost as dense as a black hole, according to Wikipedia), can you theoretically compress it into any non-zero volume? Has any work been done that shows that matter can or cannot achieve certain levels of...

Hi guys , I found a lot of incredibly useful lecture videos provided by the international center for theoretical physics see http://www.ictp.tv/ However there is one problems . They use a technology called EyA to view the lectures.It creates high quality images of the black board every 6 seconds...

I can do with just an equation, but if anyone is willing to help: Target is 25.6 m away from canon Initial Velocity = 16 m/s Time = 2.6 s Range = 26.7m No air resistance

I can do with just an equation, but if anyone is willing to help: Target is 25.6 m away from canon Initial Velocity = 16 m/s Time = 2.6 s Range = 26.7m No air resistance

Hey guys, i'll be a sophomore next year, and I was wondering about what classes you could recommend me taking then, as well as advice for future coursework. Which 4 of the following would be (the most) useful for theoretical physics? -Differential Geometry -PDEs -Fourier analysis -Complex...

Ok , Programming and me haven't been the best of friends . It kinds of irritate me , although I can follow the logic of what's going on , I find it very hard to come up with the code , I make a error and find it impossible to correct the error .What I have been learning so far is MAthematica ...

I just saw this article on cnn: http://lightyears.blogs.cnn.com/2011/12/07/diamonds-entangled-in-physics-feat/ very interesting stuff, and it basically says that whole elements can be entangled with each other. It got me thinking about a possible quantum communicator to transmit zeroes and...

Hi, I am a theoretical physics PhD in Europe and want to find a summer course for 2012 or 2013 (no matter where in the world, the topic is the primary criterion for me). Does anyone know a good starting point for this? The usual google approach is really slow, but I also was not able to find...

Hi, I have my BS in Physics and Math from the University of MN, 3 years of experimental physics research experience but no publications, about 3.85 technical GPA (but very close to 4 in Physics classes), and a good GRE Physics score. I want to go to grad school for theoretical physics, though...

Homework Statement A ball of unknown mass is attached to a massless string. The string is then held at the opposite end and the ball is pushed, as to give it a centrifical motion (acceleration toward the center and perpendicular velocity). NOTE: The length of the string is not the radius (the...

I am currently a high school student who is very interested in all of science in general, but physics in particular is most intriguing to me. While perusing possible careers in physics, I have found that most are split into either experimental or theoretical. I was wondering if you would care to...

Hi, I am searching for a school where I can have a Master of Threoretical Physics, in particular I am interested on particle physics and general relativity any suggestion is welcomed. Ah it could be on either US or UK. Thanks

Hello, since I was a kid I was always interested with the complexity of our universe and the past years I have been more interested into it. I am currently studying Systems Engineering and I am a professor assistant since my 2nd semester. Math is not a problem for me and to be honest I love it...

Homework Statement Hi, I'm trying to complete my laboratory write up over my christmas break, and I'm struggling to understand how to do part of it. I emailed the lab demonstrator on December 9th, and the head of labs on the 18th and I've had no reply off either, so I'd really appreciate it...

Like are we talking about just as well as a mathematician or does he have to know the properties of structure in math that he's studying. Not really the rigour but more like what properties it has and what it can do.

Basically what the title says. I am a junior in high school and am planning on taking AP physics my senior year and I also want to go to college for Physics (of course). But my goal is to get a Ph.D and get a job somewhere as a theoretical physicist. This is the problem though. I'm fairly...

For a while now I've known that I would like to do theoretical physics, but I'm having trouble finding out how hard the maths involved actually is. I would like to study this a Trinity College, and on their website the minimum requirements are a B2 in higher level physics (no problem, I can do...