# space

1. ### Bare and Dressed Photons in space.

Am I correct in thinking a "bare" photon in QED is represented as a qq- and a dressed photon is one that is absorbed and re-emitted via particle interactions as it passes through a medium. Does a bare photon as it passes through space interact with the zero point field and become dressed. ...
2. ### unknown vector of a closed space

can someone please verify my workings, see attached pdf and image thanks Ross Alexander Blenkinsop Perth Western Australia
3. ### Magnetohydrodynamics - Space Weather & Atmospheric currents

Hello! I would like to hear some professional opinion about a model of interactions between magnetosphere and atmosphere. I'm not a professional physicist, but I did everything, to make it fully consistent with officialy approved knowledge. I will provide you the links to publications and...
4. ### Angle of space motion and radial-velocity vector

Hello So I am trying to figure out the angle of a space motion vector with its radial velocity vector. I have to sample equations, but despite plugging in the numbers I am not getting the same answers. So I have: tan-1((4.74d(u")/(vr)) With: d = 5.14 pc u" = 0.66092" vr = -26.3km s-1...
5. ### Reynold's Theorem in One Dimensional Space

I'de be grateful for a URL to a proof of the Reynold's Transport Theorem reduced to one dimensional space. Must be a one dimensional representation no hand-waving explanation. Where is this written, I wonder? Thank ye, M'boys... JP
6. ### Can only vectors be multiplied in Euclidean Space?

After googling I could see vector product and scalar product in Euclidean Space. But can scalar be multiplied by vector in Euclidean space? If it can then I have a conclusion from the previous post. If so we can conclude that the direction does not change when a scalar is multiplied by vector...
7. ### Question about "bigger on the inside" space

I'm not an actual physicist right now, and I have no idea about anything relating to general relativity, but I saw some kind of paper on the internet somewhere titled "Calculations on space-time curvature within the Earth and Sun", and while I didn't understand any of the math behind it, it...
8. ### A space time interval conundrum

Here is a problem I have been pondering for the last week or so: In Peter Collier's book "A Most Incomprehensible Thing Notes Towards a Very Gentle Introduction to the Mathematics of Relativity" in section 3.3.5 he makes the following claim about the space time interval \Delta S^2 =c^2 \Delta...
9. ### speed of space station

After watching the interstellar movie I have a question: which solution will consume less fuel? The space station moves in a circular orbit and has too slow speed. To increase it has two possibilities: 1. Increase the orbital speed, 2. Increase the height of the orbit, and thus reduce the...
10. ### expanding space

Why would the expansion of space entail the simultaneous expansion of matter? Doesnt that require space to have a significant amount of friction if somehow it can drag entire galaxies with it? If space were expanding given any normal definition of space why wouldnt it expand without disturbing...
11. ### Is space time curvature and absolute concept?

Seeing we hear gravity warps space and time and now it seems even a rotating disk seems to warp the circumference of the disk relative to the radius and wondering whether an observer rotating with the centre of the disk would see this cirumcumference contraction; So would these...
12. ### How to convert time into space?

I was reading the proof of E=MC2. In one article it was mentioned that time can be converted to space. So time after conversion would be 300000. so speed of light c= distance/time. Now space that is the distance is 300000 and after conversion time is also 300000. So 300000/300000 we get c=1. So...
13. ### Curvature of Space

Is the shape of the curvature of space made by the earth the same of the curvature of gravity vs altitude? Is force exerted by an incline independent of mass? Is space elastic? Is this curvature caused by the mass of the object or the volume, if earth was hollow would gravity be the same.
14. ### Newton's 2nd law in curved space

Hi, I am struggling to find information on applying Newton's second law to a particle moving freely (ma=0) on a 3D curved surface like, say, the surface of a torus. What would the trajectory of such a particle undergoing free motion be if it was restricted to travel on a curved surface? So...
15. ### The Curved up space around the Black Holes

Hello everybody, It is said the space around the black hole is curved up to the extent that NOTHING can escape from it, and photons which are moving in that curved up space will remain there forever. But how is it that in the curved up space around the black hole the photons get trapped, but...
16. ### pulley system with equal force (limited space)

Hi Aplogies for what may seem a simple query, I have recently suffered a stroke and have built a simple pulley system with 8kg weight ether end to move objects back and forth over a distance of 10 meters I need to be able to move the items from one end to the other and back again from point A...
17. ### Space shuttle, energy loss, heat

Hello Space shuttle enters the atmosphere. (i) What happens to the transferred energy? (ii) how do the high temperatures generated in the shuttle enters the Earth atmosphere relate to the material used for the underside of the shuttle surface? Why is the underside not made from aluminium or...
18. ### What is the formula to find distance between two satellites in space?

I want to write program to find the distance between two artificial satellites in space every 't' seconds. My initial inputs are initial velocity, masses , radii, position(x,y coordinates) of both the satellites. Then using Pythagoras theorem I can find the initial distance between the 2...
19. ### Electro Magnetic Aerodynamics Space and Motion (body's shape and size)

Electro Magnetic Space's Aerodynamica to register Aerodynamic effect we need "good speed" what is it "good speed" definition ? For Cars on Earth 50 - 90 km/h it is not "good speed" to register Aerodynamic problems , But 130 km/h and problem rise very well I can not make in my home...
20. ### Hilbert space norm of vector invariant in different coordinate systems

Thank you for the help so far. I feel I am learning a great deal. The fourth problem of the attached problem set states let Psi be a complex-valued wave function for a particle in 1-D and gives its Fourier transform. The question asks to prove that the integral from negative infinity to...