Perspective Definition and 221 Threads

I didn't know where to post this question, but the general math forum seemed like the best idea. Newton's Laws are invariant with respect to the Galilean transformations. Maxwell's equations are invariant with respect to the Lorentz transformations. My question is, is it necessary...

I completely understand the effects of parallax as well as perspective...intuitively; but I can't seem to explain them to a particularly inquisitive child I'm tutoring. He wants to know, in conceptual terms, why objects in the distance like the moon seem to move in the same direction as you...

I thought about what gaining weight means. Isn't the following (obviously) correct? When you eat X grammes of something you momentarily gain X grammes of weight. The only way to lose weight is to go to the toilet or sweat. However, when you sweat most of the mass is water so this is easily...

Hi! I want to know, the value of perspective in exact number. Like how much is the angular convergence between two points A. Camera ----------------------------------------------------------- Building B. In the above how much would building converge, and what would be the size...

I am interested in learning math from a historical perspective. Starting with euclid and working myself up to descartes. I am thinking of a reading list to use and this is what I think I will use. I have taken math classes all the way up to calc 2 so I am not an expert and I am doing this just...

Newbie question -- Conceptualization of time dilation from matter's perspective I have only a slight familiarity with classical physics, and in trying to conceptualize time dilation in a more intuitive, concrete manner, I attempted to explain time dilation from matter's perspective. What I...

what exactly "perspective" is? It may be considered as a noob question, but I was thinking about the perspective itself, but not in terms of optics/eye focusing. 1. Why distant objects are smaller and close objects are larger? Does it have something to with amount of photons radiated into an...

Hi . I am making a robot that is supposed to detect a red ball with a camera, and then know where the ball is . The robot has a camera on top of it, that is tilted at an angle ; At each frame the camera detects the red ball and returns 2 coordinates , xp and yp which are the pixel...

Hello. I'm a college undergrad who has developed a mathematical perspective technique for drawing that I am convinced is original enough to be meaningful. Without going into too much detail, I think I have the mathematics background to formalize it, and I have the visual arts background to make...

Could it be possible that space-time curvature is not caused by matter but is an inherent characteristic of space-time? Wouldn't this explain dark matter?

I'm looking for recommendations for QFT books written from a more math perspective. I'm looking for the usual intro topics, including the standard model, etc. Ideally, emphasis on geometry and understanding. Calculating scattering in gory detail isn't my goal. From this thread...

This is a spin-off from thread https://www.physicsforums.com/showthread.php?t=499002 , which discusses a new paper on Boole vs. Bell. The question is if Bell's Theorem correctly applies Boolean logic, or if it may for example be invalid due to a probabilistic incompatibility of random...

This question will probably make the most sense to those who have read Edwin Abbott Abbott's novel Flatland. But I'm sure many others know the answer. To explain, I'll have to use some dimensional analogy. Let's say you're a 2-dimensional being. You live in a two dimensional world and thus...

Understanding "Peel-Out" From a Torque/Rotational Dynamics Perspective I've been having a lot of trouble understanding rotational dynamics involving wheels. I understand the simple stuff, but I don't understand the concepts behind the more difficult problems. Let me make this clear: this...

Hello again my dearest forum <3 I am supposed to learn thermodynamics, but all in all, books here cover only so much of a specific topic. I stumbled upon this term Latent heat. I kinda understand what it is. Its related to phase changes of matter. But is there a quantum background...

Hello, I'm looking for a book on the connection between projective geometry and perspective. Many books vaguely mention perspective drawing as the historical reason for projective geometry, but they don't go into a deep connection between the two: they mostly just use it to argue the...

A stab at any of my questions would be much appreciated. I've been mulling over the idea of pursuing a Ph. D.in Molecular Biology, genetics or something akin. I've missed the application deadlines for next year. However is it still possible to take classes towards the Ph. D. over next...

Just like we can draw 3D-looking images on paper, has anyone tried to "draw" out a 4D image onto 3D space? It's not really drawing, more like building. Since nobody can visualize 4D, it would have to be done mathematically. I've seen projections of hypercubes onto 3D, but it was still 2D since...

Hello! Please excuse me if I posted this in the wrong place. I've never been too good at these forum things, but I did have a question about atmospheric perspective that I believe has more to do with physics than any other category on the forum. While doing a personal artistic study on...

I was looking at the sky and I began to think about the stars. Obviously they emitted their light years ago because as we know, light is fast but not instantaneous. That the sky and stars as we see them, are not anymore because its only a view of their light omitted years ago. My point is that...

Hi, I'm trying to understand spinors better, and I seem to be getting stuck on understanding the reason they're said to transform differently from vectors, and I'd appreciate any help with a justification for that. I'm sure I'm missing something pretty simple, but here goes; Here's what I've...

I'm having some problems in observing the total force which. The original situation is numbered "1." There is a resultant force F_r = m_2 \cdot g - k \cdot m_1 \cdot g and because of that force m1 has the acceleration a. What I can't seem to figure out is is that resultant force...

If time dilation and lorentz contraction from a C perspective (a photon) eliminates both time and one dimension of space from that perspective, then from that perspective, can motion actually be said to have occurred? If not, then how does one resolve the paradox of a subluminal perspective...

Thinking in terms of electric circuits and electrostatic potential I understand how an electric current arises as manifestation of a difference in potential. How does this work at a more microscopic level? I.e. how does an electron know what potential it's environment is at? E.g.: If I...

A little background information. I am currently working a summer internship out at Lawrence Livermore National Laboratory and will be going into my senior year for my B.S. in Mechanical Engineering at San Jose State (in very good academic standing). Recently I have become interested in going...

i'm a physics fanatic. i love the concepts of science and physics in general. so this isn't for homework or anything just for the fascination of the science. i need some help putting a number into perspective and instead of just googling for methods to figure it out, i wanted to join a...

hey everyone, I have a dynamics course this semester and I'm not doing well. I don't really read the textbook, i read through the worked examples. I get the idea from there, then start working on problems. I try to do many problems, but i feel I'm not getting it.Usually i can't solve a...

So if space is expanding everywhere, does this mean the space in my room is expanding? I'm assuming that its expanding so slow because of the small scale, but is there still a measurable amount of space expansion occurring in my room in any time interval? If i were to wait a few billion...

Hello, I work for an OEM of Measurement Equipment. All my studies on NFPA 79 have concluded that this is a standard...not a law. If a customer wants a piece of equipment the cost of NFPA 79 compliance would be added to quotation. Can anyone give me some feedback on this. Thanks

Hello! I don't know if this is the right forum to post this doubt, but here it goes: I would like to know how to calculate perspective precedence in 3D space. (I'm not a mathematician, so I don't know if it's the correct term, but I will try to explain what I need). I have an observer...

Tried to find some info with google, but unsuccessfully. The question is, degree in what physics branches allows you to get a decent job (working on your speciality). As fai as I know, medical physicists are quite demanded right now. What else do you know?

Hi all, I am looking for either (or both) a non-technical historical account of linear algebra (the closest I've found is Crowe's "A History of Vector Analysis") or an introductory (first course) book that develops the basic ideas in roughly the order they were developed. Do such books exist?

Ok, so I know there's a significant camp of people who: (A) Think that consciousness is physical (by-product of the brain) (B) Think that they have free will, in the sense that the atoms moving around their brain don't necessarily cause their actions, or that consciousness is having a...

Homework Statement A cup is spinning around on a Lazy Susan...Homework Equations The Attempt at a Solution My question is about the perspective. The picture on my book is like this: ___________|---0.5m---\_/ ===================== So should I draw the free body...

Hello This is my first post and excuse me I'm a bit dim (hence my username). So, I've had this question rattling around in my head for a while... There are a lot of pictures of so called "Spiral Galaxies" and according to Wikipedia the taxonomy of galaxy shapes was described by Edwin...

Hello everyone. This question may sound naive, but since I am relatively new to the subject, I would like to ask for some clarification related to phonon and electrical resistivity. As most of you might be aware of, electrical resistivity of crystalline metals increases due to increase in...

Hello folks! I'm an arts instructor and painter and I intend to develop a series of works (not homework) based on the a troublesome issue (at least for me) that was out of our major in college and apparently no one I talked to had a solid answer for that. Considering that the horizon line is...

http://arxiv.org/abs/0910.5167 Gravity from a Particle Physicist's perspective R. Percacci Lectures given at the Fifth International School on Field Theory and Gravitation, Cuiaba, Brazil April 20-24 2009. To appear in Proceedings of Science (Submitted on 27 Oct 2009) "In these lectures I review...

1.Borg 2.ZapperZ 3.AbstractPacif http://img48.imageshack.us/img48/5168/img0962y.jpg 4.Andre 5.Fuzzyfelt 6.Marzena 7.Borek 8.Sganesh88 http://img26.imageshack.us/img26/674/28567437.jpg Contest Thread

Normal service resumes, contests starting on a saturday again Putting things in perspective Photos with strong perspective, odd perspectives etc etc. Be as creative as you like. Contest Rules: 1. Any digital photo or digitally-scanned photo relevant to the theme will be accepted within...

We've all heard people from time to time in their conversations ask about this riddle. Many say that they're all fat and don't know why men care about them, etc. This is what some think evolution says, plus some alternative views. I like to test ideas. What's everyone's take on this? ...

Abstract This post introduces a holistic approach to the description of the physical reality. The solution, referred to as the Dynamic Universe (DU) [1], is based on a zero-energy balance of motion and gravitation in spherically closed space. The Dynamic Universe allows the derivation of all of...

Yeah okay I have read father Janus and heeded to his judgment. The grounding of basic physics is a must and if you are looking for fact then it's best you look at other posts. Considering that a person is moving, faster than another; One an only deduce through empirical evidence that as far...

The "Photon's Perspective" Taboo There seems to be a general consensus that any attempt to try and imagine the universe form the reference frame of a photon is completely off limits. I don't quite understand this when taken within the context of other ideas which are presented here. Just...

So I have a couple of questions. Firstly, apologies if these questions are out of place, I figured this could have equally been asked on a photography board, but it involves light and position and stuff like that, so I thought it would be okay. Say for example we have two objects, object A...

Hello there helpful people (at least I hope so). I've been lurking in the shadows of these forums since I stumbled upon them a week or so ago and I have come up with a question I have been unable to find enough information for. I'm in my first year of a BSc in physics, although its pretty...

Hi there...just got through chapter 6 and I'm having some issues fully grasping the concepts... I hope I can fully convey my question coherently. Please bear with me, I'm not a physicist! This might sound pretty dumb to you who are more experienced... ;) Greene is saying that the "now"...

Hi, to pick up on marcus' https://www.physicsforums.com/showpost.php?p=2015482&postcount=67" in the sticky thread: Recently, I tried to see where this analogy could bring us if evaluated properly, and I was surprised to find that it is actually far better than what marcus pessimistically...

question(s): These are questions from an exam i took earlier tonight, but do not know if i got them correct. 1) Rain is falling with velocity 30 m/s at an angle of 60° from the vertical and is blowing due east. If a passenger inside of a train (also traveling due east) observes the rain...

Homework Statement Given if: (1) Fsm + Fem = Mm x Ams (2) Ams = Ame + Aes (3) Res ~= Rms Show that (4) Fem ~= Mm x Ame Where: 'Fsm' is the force between the sun and moon, 'Fem' the force between Earth and moon, etc. 'Mm' is the mass of the moon, 'Ams' the accelleration of the...