Relativity

I have read recently that it is believed that special relativity comes into play in very large atoms, because the "orbital speed" of electrons gets close to the speed of light. I have not thought of electrons in orbit since grammar school, their positions (as particles) being a kind of a smear of probabilities within a given orbital and the corresponding waves as standing closed cycle waves with discreet wavelengths fitting within the cycles. By what is meant orbital speed? I am a new member. If it is possible to include my email in the reply, it would be appreciated. By the way, this is the only website including physics which I could find that was at all possibl…

Here is a typical explanation of the Sagnac effect: Clearly the pulse traveling in the same direction as the rotation of the loop must travel a slightly greater distance than the pulse traveling in the opposite direction, due to the angular displacement of the loop during the transit. . . [T]he expressions "c+v" and "c-v" appearing in the derivation of the phase shift . . . do not refer to the speed of light, but rather to the sum and difference of the speed of light and the speed of some other object, both with respect to a single inertial coordinate system, which can be as great as 2c according to special relativity . . . http://mathpages.com/rr/s2-07/2-07.htm …

I've been trying to grasp the concept of 'tensors' mathematically and their role in the EFE for a long time, and kept thinking I was missing some part of the explanation. I but I think it just clicked for me. Does each tensor boil down to a 4th dimensional derivative? And when put together gives a value for velocity at a given point which can be plotted out consecutively to determine geodesics?

Good afternoon, I am part of a project called Sigma, wich is a futuristic spacial sci-fi game (if you want to know more at goo.gl/tB0amX) , following this theme, it deals with many space travels in able time. But the problem beginswhen I was studying Einstein's Theory of Relativity, the one which says the faster you go, slowest looks your time to an external viewer. Considering the distances in space, there would be needed a very faster way then light-speed travels, but in that case, theory of relativety says to reach light-speed is impossible, and even if it were not light-speed yet...It would take almost forever to reach there on Earth's point of view. For solving I've …

I have a question about the subject of gravitational waves that LIGO is searching for in their split laser light experiments. The question arose after i read an article about LIGO. The article describes the 2 detectors separated by 1865 miles, because the scientists have estimated that the wavelength of gravitational waves would be 1865 miles. Considering that general relativity is based upon geometry and math and no medium is actually described, even though they often use "fabric of space time" in such ways, do they consider gravitational waves to simply be geometrical entities as well? I grasped the possibility of the idea that gravity can be explained by relative …

Just 2 days ago, Jan 8, 2016, the long awaited follow up paper arrived. http://arxiv.org/abs/1601.00921 Hawking, et al, describe a different sort of animal, not a black hole at all, in the sense that a black hole is defined as a region of space from which nothing can escape, not even light. I suggest naming this new object a "Foo' Hole." In case it has escaped notice, Foo' Holes and Black Holes are mutually exclusive theoretical objects. Should Hawking argue his theory on this site will he also be suspended, as I, by a moderator operating far outside his pay grade? Later. Much, much later.

Does a spinning body have more mass than a stationary one. What frame of reference applies, does an observer on a spinning body interpret it as extra mass and an outside observer view it as spin? To what extent is spacetime twisted by a spinning body? Can they warp it like the coriolis force warps convection currents? If a black hole formed from a rotating accretion disk and we take the ballerina pulling in their arms analogy, the closer to the center the greater the speed of rotation. So a hypothetically large as possible disk could form a black hole that spins at a speed approaching the speed of light. How does this alter the black holes effect on spacetime.…

I was reading through this article: http://www.einstein-online.info/spotlights/bh_uniquenessand it stated : What is the need for gravitational waves? Gravity acts uniformly in all directions dependent on distribution of mass, any shaped object would be pulled inwards first at its "complicated features", eventually all features would be scaled down so much that they would be negligible. At some point they would fall behind an event horizon and be pulled into a singularity, which is the most uniform object possible, having no dimensions at all that can differ in any way. Why are gravitational waves needed to remove the "hair", isn't a singularity as bald as it …

Is it possible from earth to measure the extent of a spinning black holes ergosphere. Does the frame dragging effect have a visible signature for us here on earth, or is it only something observed by objects within the ergosphere? By knowing the shape of a spinning black holes ergosphere, and using it as an already complete part in Kerr's solution for Einsteins Field Equations, could we reverse engineer the mathematics and adjust the equation accordingly? Or would it rather just alter another part of the solution? If instead it exactly matched Kerr's solution, would this tell us anything else? Could we be confident enough in our other measurements of the BH to get…

If my rocket creates comfortable acceleration for me 1g in a galaxy cluster and if the rocket creates the same acceleration force to every one kilogram of the rocket in space between galaxy clusters then will I feel the same force of acceleration?

What implications do the relative velocity of photons have ?

Ive caught two fundemental flaws in einsteins theory. To begin with, heres a simplified definition of the theory of R, (copied off a reliable source off google) Supposing we agree on one thing and one thing only - that the speed of light is ultimate and that everything else will bend around this fact: imagine a car chase scene from your favorite movie. The guy in the car in the back opens the window and shoots the car in front. The speed of the bullet would be, say, A but the speed of the car is B, so the real speed the bullet has is the sum of A and B. Now imagine that instead of a bullet, that guy has a flashlight - he'd be firing light at the other guy; light, wh…

For years I have been plagued by an inability to understand the concept of space-time. Specifically I was never able to understand the logic behind the concept itself. I am not an expert but my understanding of space is that it is the area in which matter exists. Time is the immaterial progression of existence and we measure time using a system centered around the Earth's orbit around the Sun. (If my understanding is wrong please provide the correct answer below). From what I understand, space-time is considered to be the continuum upon which the universe exists. (Again if I am wrong please inform me). What I do not understand is how Einstein and other physicist…

Considering 4 dimensional space time or even 1 dimensional space can be said to be composed of an infinite amount of 0 dimensional points. This means a singularity takes up 0 space in our universe, having 0 space it should therefore also not have any time, so doesn't exist. Yet it can be observed via it's gravitational effects. Does it make any sense to view the collapse of a star, to a singularity, as the formation of a 0 dimensional bridge in space time. Mass in a seperate unobservable 5th dimension via gravity can then effect the lower 4 dimensions across this bridge. I mean if mass exists in 5d and we observe that mass that intersects with our 4d directly, b…

How can energy be converted to mass...what do you think?

Looking for help to understand some very basic ideas. I'd like to start with this: "In the "flat" space-time of special relativity, where gravity is absent, the laws of mechanics take on an especially simple form: As long as no external force is acting on an object, it will move on a straight line through space-time: at a constant velocity along a straight path." @ http://www.einstein-online.info/spotlights/geometry_force Why? Why will an object move at all if no external force is acting on it? How does this relate to "an object at rest will remain at rest..." If you can point me in the direction of understanding this, thanks in advance.

The Einstein Field Equation (EFE) contains scalars and tensors. The EFE may be modified if the following substitutions are applied; - A tensor is represented as a four vector product of acceleration (arithmetic product) - The Ricci Scalar is represented as a scalar ratio of areas - The Einstein constant is represented as ratios of Plank units A field operator may be defined as a “four dot multiplier”. If the field operator acts upon the modified EFE, the result will be a scalar field equation (SFE) representing field strength. The SFE may also be written as an equation of “average field strength” (AFE). If “Schwarzschild conditions…

Time-dilation due to relative velocity states that: From the frame of reference of a moving observer traveling at the speed v (diagram at lower right), the light pulse traces out a longer, angled path. The second postulate of special relativity states that the speed of light is constant in all frames, which implies a lengthening of the period of this clock from the moving observer's perspective. That is to say, in a frame moving relative to the clock, the clock appears to be running more slowly. Source - http://en.wikipedia.org/wiki/Time_dilation I disagree that the light pulse traces out a longer, angled path. Rather I propose that the length of the path …

Hello everybody! Read recently in the semi-scientific press that two Galileo satellites that were put on a wrong orbit hence are declared unusable for the European positioning constellation (GPS competitor) are to be used as a test for Relativity by observing how the onboard clocks run over the elliptic orbit. Nice, fine. Though, I'm not easy with the claim and explanation by the Press paper I read. The Press paper tells that the onboard's clock, as observed from Earth's surface, changes its pace depending on the altitude, and this will be observed. As opposed, I had imagined that both the satellite's speed (its kinetic energy) and its altitude (its potential ene…

I am interested in Special relativity and have noticed something i do not understand to do with velocity addition.If a spacecraft takes of from earth and is travelling at 3/4 the speed of light and launches a missile at a speed of 3/4 the speed of light in the same direction as the spacecraft. I used the relativity velocity addition formula W = (u + v)/(1 + uv/c^2) and this gives the speed of the missile as 24/25c (or 0.96c) if measured by an observer on earth. Now if the missile has a clock the special relativity time dilation equation say the the clock on the missile will be running at 16/25 slower. the clock on the spacecraft is running 4/5 slower to the observer on ea…

Isn't time always measured as a distance?

Practically and theoretically. Please correct me if I am wrong * but all "distances" (except in the special case of frames of reference that do not move with respect to each other or are subject to important gravitational fields **) can only be calculated (in a way that all observers can agree upon) when we take into account the nature of light and its propagation. So is this a bedrock of our physics or is it incidental *** ? Do distances between things actually exist at all unless we perform an experiment (which always requires light ) to measure them ? (ridiculously) Would they "collapse" upon themselves without the presence of EM radiation to "…

(just as a warning all my ideas here are second hand in that I have mostly gleaned them from the internet and the likes of Scientific American over the years) I do have a fairly specific question (I hope) concerning the title of my thread . I have become accustomed to the idea that the "fabric of space-time" is a misnomer and that we are really talking about an analogy. Space-time ,as I think I have learned is a mathematical model of the universe and the universe itself is ..the universe. Anyway ,when I come across the idea that the "fabric of space-time" can be "torn" to the extent that even "wormholes" can (theoretically ) be formed my wish…

The moon is rotating around the earth because it follows the curvation of spacetime. So at the moon, how large is the radius of this curvation?

I have a few questions: #1> Waste Down If I'm slowly falling into a large Black Hole .. At some point I am waste and bellow is on the inside of black hole event horrizon and waste up is on the outside of the black hole event horrizon .. Can I feel my feet? #2> Event Horizon Transitional Zone Is there a transitional zone where light might not have an escape velocity .. But it can travel some finite distance away from event horizon before being red shifted away , or pulled/bent/etc in a ballistic like trajectory back ? #3> Does gravity have a Minimum or Maximum? If not how far / what are .. the end points so far that have been experimentally tested/v…