Relativity

So I'm trying to get a more intuitive grasp of the implications of relativity, and that seems like having a good grasp of visualization. I don't need help with the math, exactly, I'm more interested in more experiential accounts, which I think will probably be a good exercise all around. Let's start with these, and maybe I'll think of more later, or you could add your own. So say you've got a big, solid disk spinning fast enough that the edges are moving at a good portion of C (to simplify, let's say .5) relative to the axis. Standing at the edge and looking inwards, what do I actually see? How about from the axis? Or say this disk is a wheel, and it's rolling…

Or is SR a special case of GR where acceleration is equal to zero ?

The "Now" Theory of the Universe Arnold Sprung 3/17/07 "Now" is the moment between the past and the future; it is what we perceive without relying on recollection. The universe (including all matter and energy) only exists "now". Its past has disappeared into "now", and its future has not yet arrived. This does not mean that the universe has vanished, it, so to speak, rolls along with "now" changing as it does so. When we look at light and other signals from the universes past, we see them as they are "now", containing their history i.e. a collection of suggestive “nows”. We are not actually piercing into the past as if we…

Abstract In frameworks special relativity phenomenon « relativity of simultaneity » has the third-rate, derivative status. The author, on the contrary, suggests considering it as a main, moreover, a unique phenomenon of the special relativity. Instead of Lorentz's transformations more simple variant of the transformations which have been not concerned with distortions of a spatial and time scale is offered. This variant eliminates paradoxes that irritate sensible people. That fact is underlined, that the suggested methodology strictly corresponds to materialistic outlook, as against plainly positivistic methodology on which till now it is based special relativity. _…

Hi all, I hope this is the correct place for posting this thread, if not could someone move it please. There are a few things that I have been thinking about, these may reform the way we look at time and hopefully someday will enable faster than light travel and maybe time travel as well. I am only posting a part of my thoughts in this post, more will come either as replies to this post or as new topics. I am posting here so members of this forum may help me unravel the jumble of thoughts in my head and also help with some eguations I get stuck with. Time as a fourth dimension. Time is now generally taken as the fourth dimension of spacetime. Now has anyone ever …

(sorry posted this first in Quantum mechanics by mistake:confused: ) Does anybody know what the formula is for the graph you see in text books, of speed against time for a constant force applied to an object. The one where speed increases with time, and then levels of as it approaches C. For non reletavistic speeds I think the formula is f=ma, which when re-arranged would give t=mv/f. and for a force of 1N applied to a mass of 1kg t=v. So after 10 seconds the mass would be doing 10m/s,after 20s 20m/s. But at speeds close to C we know that this is not the case, so does anybody know the formula that matches the graph I mentioned?

I've been working with geometric expressions of special relativity. In this process and version of illustration I have found some interesting conclusions and would like to recieve some peer input. Please note I am not arguing against relativity. I am just working with results aquired in this version of expression. If I may I would prefer to link the original thread for simplicity. Please respond on this thread. Animation example Work and conclusion example

42.7 grams of Cu represents how many kilograms?

I don't get this - when you move very fast (say 0.5c) the time slows down relative to outside of your ship. If you looked at the planets around you, it would seem like they spin faster than before. But if they look at you, it would seem like you move slower than you were supposed to (0.5c). Also, you spent certain amount of energy to accelerate to 0.5c but you actually move slower. Where does the unused energy go?

Suppose you travel at 0.9999999c in a spaceship and you turn on a flashlight forwards. As far as I know speeda light is always constant 3*10e8. So it will fly out at that speed. But relative to what - the spaceship or our inertial frame of reference (outside the ship)? And i have another, a little off topic question. When you fly at speed close to speeda light, you notice that outside observer's (at rest) clock is running slow. The outside observer also notices your clock running slow, right? I don't really get that. Sorry, for offtopic again but don't wanna create three different threads: concerning equation E=mc*2. I don't get why speed of light affects amount of ener…

Einstein does not define the units for distance (m) and time (s) independently of the speed of light c. Special relativity defines a time interval as distance divided by c and distance as time interval multiplied by c: c = 300.000.000 m/s s = 300.000.000 m/c m = cs/300.000.000 If, in the equations above, we substitute s or m with their respective definitions we obtain: c = 300.000.000m/300.000.000m/c <=> c=c The statement c=c is surely always true independently of the actual value of c. This is a classical example of a circular argument. If the units of measurement are defined by nothing more then the postulate of the universal constancy of c then …

We all know that a photon has no rest frame, and so it travels at the speed of light. My question is, what is happening at the event horizon of a black hole? Isn't the event horizon the plane where even light can not escape? At the event horizon, is the light in a rest frame?

I have resumed working on going through the logic of modern physics as part of the quest for a more systematic and philosophically consistent approach that may help solve some of the fundamental issues and unify not only the mathematics but also the logic and philosophy which has been severly lagging for too long. Intuitively general relativity can be given a very natural and plausible abstracted bayesian interpretation, where the geometry identified with probability priors and geodesics are simply the most basic a priori rule for evolution. Anyway, I have not spent alot of time reading every possible treatise on the subject so I wonder if any of you guys on here…

TWO QUESTIONS PUT TO “EINSTEIN” Α. GRAVITATIONAL AND INERTIAL MASS Let us assume that Ο.ΧYZ is an inertial frame of reference and (Ο) is an observer standing in it. Also, m0 and Μ0, (m0 < M0) are two masses which at time t=0 are at rest and lie at a distance h from each other. We now let the two masses m0 and M0 move freely under the influence of the universal force of attraction. After a time t > 0, the distance between the two masses m0 and M0 will be h΄, (h΄< h) and their velocities v and V respectively, (“two-body problem”). As it is well-known, according to the Theory of Relativity, when a mass moves relative to an inertial observer…

I can not derive the Fermi Walker transport equation to save my life, help! The Fermi Walker transport equation is [math] \frac{{d\hat e_\alpha }} {{d\tau }} = - \Omega \bullet \hat e_a [/math] where [math] \Omega ^{\mu \nu } = u^\mu a^\nu - a^\mu u^\nu \[/math] with u and a being the proper velocity and acceleration. I can derive the equation for a Thomas precession with [math] A_T = I + \frac{{\gamma ^2 }} {{\gamma + 1}}(\vec v \times \delta \vec v)S + (\gamma ^2 \delta \vec v_\parallel + \gamma \delta \vec v_ \bot )K \[/math] with [math] S_{1 = } \left( {\begin{array}{*{20}c} 0 & 0 & 0 & 0 \\ 0 & 0 & 0 &…

Okay, my understanding of general relativity is pretty basic but... If I sit in a chair on rollers with a bottle of water on a table 2 meters in front of me then spin in a complete revolution in 1 sec, by relativistic principles... The bottle has traveled a distance of 2pi*r, or 12.5 meters around me at a rate of 12.5 meters/sec. Is this correct?

I was watching that show about einstein on the science channel and there was a sentence on there that said something to the effect of "why does what happen to one atom in one place, happen instantly to another atom a million light years away". Is that or something related to that true? And about the reaction thing. Lets say a giant planet, say 10 million miles in diameter, crashes into another giant planet a couple million miles in diameter. Could the reaction to that impact be felt 186,000 miles away faster than a second? Or would it all from a distant eye seem to just be happening in slow motion as everything is so frickin big yet the effects of those causes can't h…

Is gravity carried by a particle, like how visible light is carried by photons? Also does other forms of radiation other than visible light like gamma or radio carried by a certain particle.

Does anybody know what the formula is for the graph you see in text books, of speed against time for a constant force applied to an object. The one where speed increases with time, and then levels of as it approaches C.

Can someone tell me if this is right please? Theoretical yield of H2SO4: Relative atomic masses: H = 1; S = 32; O = 16; N = 14 Molecular mass of sulphuric acid H2SO4 = (1 x 1) + 32 + (16 x 4) = 97 Molecular mass of ammonia solution NH3 = 14 + (1 x 3) = 15

Has anyone heard about zyzion.com? This guy claims to have the first successful controlled fusion reactor. His high res photos show the thing in action, it's amazing!

suppose for the moment, that we had a means of converting mass directly into harnessable energy. if that energy were put out the back of a rocket as light, it will behave as though the propellant mass were moving at c relative to the rocket, but only if you look at it from a newtonian dynamics perspective. if we factor in inertial dialation, at what speed will mass need to travel as propellant to muster the same force as that mass-energy from a laser?

Say two spaceships are moving apart, both at 0.9c (relative to stationary observer) Wouldn't they observe movement faster than c? Because in realative velocities addition formula there are no "squares", therefore negative velocities do matter. So I believe the velocity of one ship relative to the other would be roughly 1.8c. (Of course I don't really believe it because nothing can travel faster than light, I would just like to know where I am wrong)

Everybody always says you have to measure things such as speed and distance relative to something else, which is true. But what if everything has an absolute position within the universe. Like the universe was a big 3D grid, with the center being the point of the Big Bang. It is expanding infinatly, on all sides, but the center is still the same. That means that everything could be measured to have an absolute position within the universe. How to measure the dead center of the universe? Equal distances from all sides, because it is expanding at an equal rate on all sides right? Also you could argue that things are moving so fast and even expanding, so they are never in th…

Now I know it would take an infinite amount of energy and an infinite amount of time to accelerate to c but would it be possible with a solar sail that goes unimpeded and never loses sight if its star? Or would the light intensity be innsuffiecient after a point, because the way I understand it, the light from the star will always reach it (as long as it is not blocked or bent away), then the sail will always be accelerating because there would not be much of a retarding force other than gravity.