Important Definition and 498 Threads

Hey all, I am currently a freshman double majoring in Physics and Math at Purdue University. I have been recently creating a schedule that orders all of the courses I need to take and those that I want to take for the rest of my undergraduate endeavors. I know that it's rather early to do...

Indicate the papers you think will prove most significant for future Loop-and-allied QG research. The poll is multiple choice, so it's possible to vote for several. Abstracts follow in the next post. The poll format has been expanded so as to allow more candidates. I brought forward three that...

I have always wondered various questions, out of which these 3 below are on the priority list including a previous topic I questioned here ofcourse without any answer to it. I am no science guy by the way, just curious! So the questions are: 1. Can a black hole contain a wormhole inside of it...

I'm a second year student at university studying mathematics. I'm having troubles deciding between a few modules and I hope you can help. http://www.ucl.ac.uk/maths/courses/undergraduates is where all the modules are, please take a look at "Honours Year 2" I get to choose four modules, and so...

Clock transport can be used to compare one clock with another in an absolute sense. All we have to do is to transport a clock between two A-frame clocks that have been synchronized per Einstein's definition. Let's call the transported clock "T" and the left-hand and right-hand E-synch'd clocks...

Why are they important? I've been learning about them quite a bit and have no idea why they are significant. What is the motivation for their discovery, their use, or even their mention in physics for that matter. All I really know is that when you look/have solutions with the same angular...

I'm still very new to the world of calculus and physics, and while I understand how to do limits and such, I don't understand the usefulness of them, and I'm hoping some of you can help me understand why limits are important and why we bother with them. Here's my understanding of them...

I would love some suggestions about my undergraduate research, thought it may be improper to ask here. I apology if I break the group rules. My undergraduate research topic is dark matter. My plan so far is to study important observations before making other progress. I have found an...

I have never took notes in my life.I just listen to the lecture and read the material from the book but I have never jotted down anything during the lecture.Considering that I recently started university, is note taking really important or can I just study without it?

This is the second half of the poll. Of the ten candidates in Part II, please indicate the ones you think will prove most significant for future Loop-and-allied QG research. The poll is multiple choice, and it's possible to vote for several papers. Abstracts follow in the next post. Here's a...

There are twenty candidates, and the poll is divided into Parts I and II, each with ten. The poll is multiple choice so it's possible to vote for several papers. Please indicate the ones you think will prove most significant for future Loop-and-allied QG research. Abstracts follow in the next...

Right now I'm seeing multivariable calculus and differential equations. I can apply all the rules they teach in class and solve all the problems with the correct "method". However, I'm starting to worry that I don't know how to prove anything! For example, if I were teaching implicit...

Why do physicists find naturalness as some important feature a theory should contain? Since the choice of the theory's parameters is quite abstract (or can be experimentally determined), what's the reason a constant that you put by hand and can take values from 0 to "infinity", be constraint to...

Hiya! I am a beginner in programming and I am now having a java course in college... In the first few lessons, we are taught that programming involves declaration of variables and variables are classified into several categories (e.g. int, float, boolean, double, etc.). I wonder why we have to...

I've noticed that the vast majority of named or important mathematical constants, are what you might call small numbers. Their modulus lies very often in the range [0,5]. Here's two examples of tables: http://en.wikipedia.org/wiki/Mathematical_constant#Table_of_selected_mathematical_constants...

Author: ZapperZ https://www.physicsforums.com/insights/important-thing-learned/

Hey everyone, I'm currently attending a community college, and heading into my last year here. I'm starting to fill out my transfer applications, and I was wondering how important it really is to attend different universities for your undergraduate and graduate degrees. I've always heard that...

after it was found out that the first 9 pi digits 141592653 result in the end sum of 9, i searched for its iteration in the large digit chain of pi. after scanning stuff.mit.edu/afs/sipb/contrib/pi/pi-billion.txt it was found that .141592653 occurs at the 427238911 place and ends on the...

We have quite a close and tight community here. And we do not really realize it, but for some people this forum is an important piece of their life. Other people just use this forum to get help in school or with other aspects of life. How about you? How important is PF for you? Why? What do...

I am very interested in biochemistry, and in particular the metabolism of the cell. Important molecules for cell metabolism are ATP (and ADP) and NAD+ (and NADH). ATP, ADP and NAD+ are ions: ATP and ADP have negative charge (as have the free phosphate ions) and NAD+ has positive charge. But the...

Of the twenty candidates, indicate the ones you think will prove most significant for future Loop-and-allied QG research. Since the poll is multiple choice, it's possible to vote for several papers. Abstracts follow in the next post. http://arxiv.org/abs/1406.7304 Entanglement entropy and...

Sometimes it happens that hamiltonian has degenerate eigenvalue. This degeneracy can be removed by modifying the Hamiltonian. If the modification is additional term proportional to an adjustable parameter, the resulting difference between the eigenvalues can be made arbitrarily small. Is...

I know cloud computer has been around in some form for a good deal of time but all the sudden it is taking off. People are deeming it the future of computing, why is this? what does cloud computing mean for the future of computers and storage et cetera. Thank you

Hello all, I am currently a tenth grader. I want to know how important the college you go to is. Is it true that to excel in physics you have to go to the top ten? Or is it what you do at college that is important? Thank you in advance.

What's up everyone! I'm a junior in HS right now and have been trying to improve my math skills after reading a bunch of stuff on jobs and how math and science skills are very important for getting a good job in our economy here in the U.S.A. I've been sort of "ok" my entire life at math...

Hi. I did poorly in HS math due to many reasons, but now I love it and have received ~ 100% on every exam in the past 4 remedial math classes. Next I start cc version of precalc. So lately I've been feeling like my cc is teaching us watered down math. For example, logarithms are not introduced...

Of the twenty candidates, indicate the ones you think will prove most significant for future QG research. Since the poll is multiple choice, it's possible to vote for several papers. Abstracts follow in the next post. I've included two non-QG-related Dark Matter papers at the end because of the...

Perhaps, this is an easy question, but still induces a lot of confusion to my self. I might not be the only one confused with the meaning of these concepts so it can help a ton to people, like me, confused with their meaning. So here is my confusion, Matter, as I researched it, although instead...

I am just a student. I read that if the strength of weak nuclear force were stronger than current value, this would cause the rarity of neutrons. And, if the strength of weak nuclear force were weaker than current value, this would cause most of hydrogen to convert to helium. I can't understand...

Of the twenty candidates, indicate the ones you think will prove most significant for future QG research. I've included two papers from earlier in the year which I mistakenly overlooked when they first appeared. Since the poll is multiple choice, it's possible to vote for several papers...

For example, I want to work on quantum gravity and things like Brane cosmology (but not necessarily string theory). I'm really interested in sinking my teeth into differential geometry, general relativity, the shape of the universe, stuff like that. But if I were to go to a grad school that...

Hello all, I'm still a math newbie. I'm just about finished with part 1 of Spivak's calculus; this is my first experience with more advanced math / deeper understanding (in high school and college I did well in calculus because I could memorize to perform operations, but I never had to...

Homework Statement Consider the tangent surface of some regular differentiable curve given as X(t,v) = \alpha(t) + v \alpha'(t) . Show that the tangent planes along X(t,constant) are equal. Homework Equations N = \frac{X_{t} \wedge X_{v}}{|X_{t} \wedge X_{v}|} The general tangent...

I just need to know the basic ideas of topology, and the most important results, because I'll have differential geometry the next semester. Does anyone have a good material for this? Or you can just say what to search for and I'll search it. Thank you :)

Of the twenty candidates, please choose the one(s) you think will prove most significant for future research in Loop-and-allied quantum gravity. Since the poll is multiple choice, it's possible to vote for several papers. Abstract summaries follow in the next post...

Hi, Iam having a hard time understanding the benefits of using a semiconductor to construct e.g. a photodiode that creates a current in proportion of the energy deposited by radiation. Text books says that semiconductor is preferred as detectors due to high density (larger chance for...

Can someone explain to me, one with extremely limited knowledge of the concept of Turing Machines, what these hypothetical machines help us understand or accomplish in computer science?

I was reading through Harvard's graduate school admissions FAQ, and a paragraph said:"The physics department's admissions committee reviews each candidate's entire application, including statement of purpose, transcript, experience, GRE scores, and letters of recommendation -- the statement of...

is programming important in engineering?? Hello how are you guys?? so my question is how important programming languages are in the Mechanical Engineering ?? is being professional with programming languages very helpful and will increase job opportunities?? how about other disciplines...

I have couple of questions regarding human speech 1) Whatever sound we make, there is always sound of a vowel. Why is that? 2) A bit unrelated but still - We can produce a limited number of sounds or phoneme. And each language tries to get a symbol for it. Why some languages choose to have...

Apologies if this has been asked before but I couldn't find any posts with the exact question. I'm about to go to college but I haven't decided my major yet. I have loved physics, particularly astronomy, ever since I was a child. I used to read a lot of astronomy books when I was younger...

I'm taking QM next semester and I'm studying Griffiths to get a leg up. I've noticed so far that a lot of the problems aren't hard per say but instead just require the integration of annoying functions. The kinda of stuff I hated to do in Calc II because I got a Disgraphia. As a matter of fact I...

Hey everyone, I was hoping to get some input on this question. I'm starting up an algebra based general physics sequence this fall, and I'm wondering how important basic geometry is going to be for it. I've never actually taken geometry, but I've done a decent amount of self study. I went...

I've taken freshman physics I and II about a year ago (I don't remember too much from it..) and I was wondering how important they are to the junior year classical mechanics? I've noticed that a lot of learning resources online for physics starts at the junior year classical mechanics and it...

Of the eighteen candidates, please choose the one(s) you think will prove most significant for future research in Loop-and-allied quantum gravity. Since the poll is multiple choice, it's possible to vote for several papers. Abstract summaries follow in the next post...

Hi, I really need help with this as exam is tomorrow The question is to find the points on the cardioid r=a(1+costheta) where the tangents are perpendicular to the initial line here is the answer http://gyazo.com/e8b4cbd36f0ef71d0cdf13be256d8618 Why is pi not included in the...

I understand that too long of a time scale won't resolve an event clearly, and too much has the risk of exciting whatever you're trying to measure. Is there some sort of resonant effect when you match, say, a radiation frequency to the time of an event taking place? Specifically I'm applying...

How important in the grand scheme of things is the ranking / pestige of the university that you attend for your undergrad degree? I'm not going to specify a subject but assume its within engineering or the physical sciences to narrow it slightly. How much if any does it contribute to your...

I'm going through a whole undergrad quantum book (Townsend) by myself. It has a chapter on path integral QM. He said in the intro that it can be skipped, but I was wondering if knowledge of this subject is immediately helpful when starting graduate level quantum. I start grad school in the...