Einstein Definition and 788 Threads

Just wondered if the following extract is historically correct ... Einstein's and now main stream's current gravity theory is based on the belief that if you were accelerating in a spacecraft you wouldn't be able to distinguish between this experience and that of gravity. It was then...

Homework Statement Use the equation ln(q+N) to derived an equation similar to the equation, omega(N,q)=e^(N*ln(q/N))*e^(N)=(eq/N)^N only when q >> N, for a multiplicity of an einstein solid in the "low temperature" limit , q<<N Homework Equations ln(q+N) ln...

Homework Statement For an einstein solid with four oscillators and two unites of energy, represent each possible microstate as a series of dots and vertical lines. Homework Equations no relevant equations The Attempt at a Solution I won't list all my microstates, just a couple of...

Homework Statement From the formula t = \frac{L}{v+c} + \frac{L}{v-c} I've made t = \frac{2L}{c}\left(\frac{1}{1 - \frac{v^2}{c^2}}\right). This is the problem: \left(\frac{1}{1 - \frac{v^2}{c^2}}\right) = \left(\frac{1 + \frac{v^2}{c^2}}{1 - \left(\frac{v^2}{c^2}\right)^2}\right) How...

Homework Statement (a) The formula for the multiplicity of an Einstein solid in the “high-temperature” limit, q >> N, was derived in one of the lectures. Use the same methods to show that the multiplicity of an Einstein solid in the “low-temperature” limit, q << N, is Ω(N,q)=(eN/q)^q...

This is more of a historical question than an actual physics question sorry... but it is physics related so here it goes I know when they first met Einstein and Bohr became good friends but does anyone know if they stayed that after all their famous debates about the paradoxes of quantum...

The title of this thread comes from https://www.physicsforums.com/showpost.php?p=2038753&postcount=23" in the Cosmology section of PF. It started a mini-thread that has nothing to do with cosmology, but it's quite interesting, so I thought I'd kick off a discussion here. The general topic...

How did Einstein come to pushish his general theory of relativity? Was it in a series of papers over a few years, or in one definite article? In either case, are these (or this) papers available on the internet in engligh? Thanks.

If gravity is a force, then the moment the object producing gravity is taken away, it should result in gravity taken away instantaneously. However, why does Einstein say that Newton's classical mechanics are incorrect and that in fact he decided to propose spacetime and not follow what Newton...

http://arxiv.org/abs/0901.0640 Horizons and the cosmological constant Krzysztof A. Meissner 6 pages (Submitted on 6 Jan 2009) "A new solution of the Einstein equations for the point mass immersed in the de Sitter Universe is presented. The properties of the metric are very different from both...

It's becoming a little more well-known in recent years that Einstein was in fact a strong advocate for a "new ether" from 1916 until his death. He denied the 19th Century version of the ether in his 1905 paper on SR, and spent about 11 years defending his banishment of the ether from physics...

Could anyone explain: http://en.wikipedia.org/wiki/Einstein-Cartan_theory I don't understand why if #3 (Experimental effects are too small to be observed) there is a 'proof' #2? What is a 'flaw' if there are no observed effects?

Photo of Einstein, Hubble, and LeMaitre together?? Hey, I was wondering if anyone knew where i could find a picture of Einstein, Hubble, and LeMaitre together. I think they were all together in California in the 1930s and if anyone knows anything about this, i'd really appreciate the insight...

Consider the relative position of the inertial reference frames I and I’ as detected from I when the standard synchronized clocks of that frame read t. The reference frames I and I’ are in the arrangement which leads to the Lorentz transformations of the space-time coordinates of the same event...

Homework Statement the stiffness of the interatomic "spring" (chemical bond) between atoms in a block of lead is 5 N/m. Since in our model each atom is connected to two springs, each half the length of the interatomic bond, the effective "interatomic spring stiffness" for an oscillator is 4*5...

I stumbled across the following list of Einstein's papers... Somebody asked a related question on this forum recently...and this would help. http://en.wikipedia.org/wiki/List_of_scientific_publications_by_Albert_Einstein Is there a better place to post this?? Can it be posted in the...

i heard this story a while back: einstein was given a toy by one of his long time friends. it was a little ball with a string attached. the objective of the toy was to get the ball on the string to sit on the rod... here's a picture that looks like the toy i remembered in the photo...

Einstein Online is an amazingly informative website that the AEI (Albert Einstein Institute) started in 2006 and is still adding to. They have a section on cosmology that is the best introduction I know of not needing a lot of math. Indeed it is nearly math-free but still manages to be...

Dear all, I'm coding the calculation of the free energy of an SiO2 crystal structure Using a 2-body Buckingham potential. I'm attempting to use the method of Frenkel and Ladd which consist in transform your solid reversibly into an Einstein crystal. I've read the excellent book...

Why do we ever get Einstein crosses? I realize it is because the alignment is not right, but why do we get a cross because of this instead of just a skewed ring? Thanks, Jamie

Was Einstein too optimistic? I’m beginning to suspect that this philosophical view is nonsense. There seem to be many aspects of the physical world that are really difficult to understand and fully accept. But then lots of people grasp stuff better than I do. I’ve been trying to devise...

When it is about the "Lorentz transformations" I have in mind: There is indeed a state of real rest, defined by the ether. Hearing about "Einstein transformations" I would think: The notions of "really resting" and "really moving" are meaningless. Only relative motion of two or more uniformly...

So back around 2006 I was reading a bunch about how people were worried that the "Beyond Einstein" program was losing its funding. This was a set of five or so astronomy probes investigating edge astrophysics, and they were talking about funding maybe one or two of them (one of the probes was...

A couple questions. Assume that you can travel arbitraily close to the speed of light and that you have figured out how to communicate via Quantum entanglement (Like Ender's Game). I speed away from Earth at almost the speed of light. At the point when I stop accelerating, is it not valid...

Imagine we have an ideal Schwarzschild black hole. A small satellite of insignificant mass (so that the Shwarzchild geometry remains ideal) is orbiting at coordinate radius R just outside the photon orbit in a perfect circular orbit. For the purpose of this experiment ignore the orbital decay...

Solving the Einstein eq. i found the following differential eq. that would descrive the metric inside a body: x2d2y(x)/dx2+2xD1(y)dy(x)/dx+D2(y)=0 where D1(y) and D2(y) are known function of y and 0<=x<=1. I try to solve numerically but looks like there is a cusp; any suggestion how to...

Could someone please help me understand the Einstein hole argument (as outlined by Norton, see below). In particular the step that says that the second solution within the hole is a valid solution to the generally covariant field equation. I think my understanding of general covariance is at...

What physical meaning can be ascribed to the non-divergence of the Einstein tensor? I find it counterintuitive since I associate divergence with field sources (like the electrical field of a proton) and obviously a gravitational field has a source. Is there a parallel with Newton's formulation...

1. Absolute simultaneity with standard synchronized clocks In an one space dimensions approach we propose the following scenario. At the origin O of the inertial reference frame I we find a clock C0(0) and a source of light S(0). An observer R’ moves with constant speed V in the positive...

I had just by chance mentioned something about Albert Einstein today to my colleague when a heated debate began at the office. We were talking as usual when he threw out that although Einstein was an accomplished physicist, Isaac Newton was the greater of the two because of his work in...

Hi, Why is -BEi used instead of +BEi as the lagrange multiplier for indistinguishable particles? How is it justified? I've been reading a book about statistical mechanics and it introduces lagrange multipliers first for distinguishable particles- it has ln(ni) + a + BEi = 0. (where a is...

I'm curious about how people here view Einstein's prescription for determining simultaneity in an inertial frame, and how the extension of that approach to other inertial frames spawns the Lorentz transformation. It seems to me the competing pictures here are that this is an arbitrary way (in...

Is this the right place to discuss Bose Einstein condensate.

Einstein v. Wheeler's Black Holes John Wheeler who died earlier this month (13 April) not only coined the term 'black hole', but is of course closely identified with the very concept of a gravitationally collapsed object. So he surely carries much of the blame for the basic deviation...

I could do with some help understanding this. That einstein photon particle energy equation E=hf Considering the mimimum energy ( Planck energy ) set E = h That means f=1 What? Is the f dimension in 1/sec? It can't be right. Why would the minimum (planck) frequency happen to be 1 per...

Homework Statement I have a paper due Friday in ap Physics and i can't seem to find anything on the subject that doesn't involve reading an entire textbook. Ok so we first must compare/contrast Newtonian & Einstein Physics, then explain their contributions to Quantum mechanics. The...

can anyone give me the webpage link of this paper by Einstein Einstein, Albert, 1911, "On the Influence of Gravity on the Propagation of Light", Annalen der Physik, 35: 898–90 I heard that in this paper Einstein tells that velocity of light is changed by gravitational field...i want to...

What are the appropriate units for the left half of the GR equation? Meters? square meters..? To put it another way, what exactly is being quantified?

Did Einstein "guess" the time-dilation equation? I can't find anything on the net, but it seems to me that Einstein would have had to "guess" the time dilation into existence. Furthermore, supposed "proofs" could be hoaxes.

goooooovy man http://www.youtube.com/watch?v=QxbutNmaL-s&NR=1 addendum: any body know any other soliton waves in nature that are this aeshetically impressive?

I have been trying to show that the Einstein ring radius R_e = 2[GMx(L-x)/(Lc^2)]^1/2 to no avail. can someone who knows this show me, or at least point out the direction. I have a strong hunch that i'll have to use the light bending formula for small angles
delta_phi = 4GM/(bc^2), and...

Homework Statement Use Sterling's approximation to show that the multiplicity of an Einstein solid, for any large values of N and q is approximately \Omega(N,q) = \frac{(\frac{q+N}{q})^q(\frac{q+N}{N})^N}{\sqrt{2\pi q(q+N)/N}}Homework Equations \Omega(N,q) = \frac{(N+q-1)!}{q!(N-1)!} \ln(x!)...

I Read That Einstein Began Searching For An Explanation Of Gravity In The Em Waves... I'm Not Aware That This Has Been Proven To Be Wrong. I Only See That Em Has Been Related To The Weak Force.. Can Gravity Be Only After Em Waves Exist Or Does Gravity Exist At And Within The Weak And Strong...

If General Relativity is background-independent, and, as Einstein himself said, general covariance "takes away from space and time the last remnant of physical objectivity," why do you think it was so hard for him to accept the possibility that quantum mechanics also could be non-local? Are...

Einstein Summation Convention / Lorentz "Boost" Homework Statement I'm struggling to understand the Einstein Summation Convention - it's the first time I've used it. Would someone be able to explain it in the following context? Lorentz transformations and rotations can be expressed in...

Homework Statement 2.Explain in your own words what Einstein means by “the principle of relativity”, and why it seems to be incompatible with the theory of electromagnetism (or “the law of propagation of light”). Homework Equations Not an equation but Einsteins answer can be seen here in...

How does Einstein’s theory of special Relativity explain the result of the Michelson-Morley experiment? Iv'e tried numerous times to do a google search but got no clear answers. if anyone could help it would be greatly appreciated. thankyou.

How does Einstein’s theory of special Relativity explain the result of the Michelson-Morley experiment? Thankyou if you can help

Are the phrases "Linearized gravity", "Linearized Einstein Field Equations", "GEM (gravitoelectrodynamics)", all referring to mathematically equivalent approximations of Einstein's full non-linear field equations? If not, could someone tell me what order (in some rough sense) these would be...

Homework Statement Is \partial ^ {\nu} F_{\mu \nu} + m^2 A_{\mu} the same expression as \partial _{\nu} F^{\mu \nu} + m^2 A^{\mu} ? What form of the metric do I need to hit them with to show that? Also is \partial ^{\nu} \partial_{\mu} A_{\nu} = \partial_{\mu} \partial ^{\nu} A_{\nu}...