Questions tagged [relativity-theory]
For questions regarding either the special or general theories of relativity.
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Where did the popular idea of spacetime come from?
[This question is about popular conceptions and therefore goes into strange directions, don't get too shocked]
The notion of spacetime can be traced back to roughly the 18th century where some people ...
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Why didn't Einstein propose any metric solution to his equations?
I've read about general relativity (GR) recently and something stroke me: Einstein came up with his equations in 1915, linking the metric of spacetime to the distribution of energy (more exactly, to ...
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What are some outdated concepts in general relativity?
Inspired by outdated concepts in special relativity such as When and why did the concept of relativistic mass become outdated? and Special relativity and imaginary coefficient of the time coordinate, ...
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What is the origin of the rubber sheet analogy?
I am trying to track down the first use of the 'bowling ball on a rubber sheet' analogy to explain spacetime curvature in general relativity. I have found a lot of secondary sources that give ...
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Historical origins of the idea that information cannot travel faster than light
Is there a good book or other reference that discusses the historical origins of the principle that not even information can travel faster than the speed of light? In my understanding the main reason ...
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Did Einstein attribute a physical meaning to the affine connection in his unification models?
As seen in Einstein's 1920 address from the University of Leiden, for example, he did consider it meaningful to distinguish between the presence and absence of the aether, and certainly he seemed to ...
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Before Einstein did people realize about a falling man not feeling weight?
I understand that Einstein was able to draw remarkable conclusions and was set on the path of General relativity when he realized that a falling observer not feeling his own weight.
But is it believed ...
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Weyl's gauge theory and railroad tracks
There is a claim I occasionally read that the origin of the word "gauge" refers to a track gauge used in railroad tracks (the distance between two rails). It's a claim I have seen here, here,...
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Density effect of energy loss of fast ions as a test of relativity
I am thinking about the relation between the Nobel physics committee and Einstein’s relativity theories. It was clear in 1922 based on the bizarre inscription on the committee’s handcrafted diploma ...
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Paradigms in Newtonian physics around 1900
I am thinking about the change from Newtonian mechanics to quantum physics and relativity.
I note that we have accepted the words "ultraviolet catastrophe" in connection with the situation ...
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Did Einstein believe the laws of physics would be replaced by mathematical identities?
I'm sure this wasn't his intention at the outset, but here's my understanding of the history of GR so you can see where I'm coming from:
The Einstein-Grossmann "Entwurf" version of the ...
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What did Einstein say about the Dirac equation?
The wiki article on Dirac quotes Einstein as saying of Dirac
I have trouble with Dirac. This balancing on the dizzying path between genius and madness is awful.
and
I don't understand Dirac at all.
...
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Interviews / Conversations with Einstein
I'm searching interviews and/or conversations (in English) with Einstein as text. Is there something available? In particular physics (e.g. theory of relativity) would be interesting but also other (e....
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Origin of the terminology "Einstein frame" and "Jordan frame"
Consider a classical scalar-tensor theory (I'm following this paper)
\begin{equation}
S=\int d^4x\sqrt{-g}\left(
\frac{1}{2\kappa^2}\mathcal{A}\left(\Phi\right)R
-\frac{1}{2}\mathcal{...
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Is there history of all the blind alleys Einstein followed between 1905 and 1915 in formulating General Relativity?
My impression is that the equivalence of the force experienced in an accelerating elevator to the force experienced as a result of gravity is what inspired Einstein to quantify gravity in terms of the ...
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Hilbert's criticism on the first version of Einstein's field equations
Crossposted at Physics Stack Exchange
I have read once that Hilbert had some reservations regarding the first form of the field equations
$$ R_{\mu\nu} = k T_{\mu\nu} $$
because it was not possible ...
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References for Laplace's question regarding Newtonian Gravity
In this lecture by Prof. Frederic Schuller @ 17:49 , it is said that Laplace asked a question if force could be seen equally as curvature of the underlying space which the particle moves in. However, ...
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Is Edmund Whittaker claim that Hilbert proved General Relativity days before Einstein valid?
Are the claims of Sir Edmund Whittaker regarding David Hilbert's derivation of the general relativity theory predated that of Einstein by five days?
This Wikipedia article that I found contains the ...
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How did they know that the space could expand?
The theory of general relativity was formulated around 1915 which could be summed up in words of John Wheeler, "Space-time tells matter how to move; matter tells space-time how to curve".
At ...
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Bardeen's missing talk
Back in 1968, James M. Bardeen gave a talk at the GR5 (5th international conference on gravitation and the theory of relativity), in which he presented a slight modification of the Schwarzschild ...
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Physical theories and Mathematics [closed]
I study pure mathematics. In pure mathematics, we begin from some axioms and obtain theorems. I am also interested in studying physics. I have some questions about the relationship between physical ...
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Did a Chinese astronomical text conduct the "Galileo's Ship" thought experiment around the 2nd century BCE?
A math and physics magazine I was browsing through contains the quotation
The Earth is moving constantly, but people do not know it; like the
crew in an enclosed ship, they do not notice it.
The ...
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What was Einstein's first publication of the final form of general relativity?
What was Einstein's first published exposition of his final form of general relativity, be it a scientific article or a book?
I've been googling the answer for hours now, with no luck, really. The ...
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Who was the first to hypothesise that gravity from one mass causes the spacetime around another mass to curve?
Was it Einstein? Or was there someone before him to hypothesise this?
Shannon T
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How did Mach's view on spacetime differ from Einstein's?
We can read in Wikipedia:
Mach's principle, in cosmology, hypothesis that the inertial forces experienced by a body in nonuniform motion are determined by the quantity and distribution of matter in ...
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Who named Black Hole?
A black hole is a compact region of spacetime where gravity is so strong that nothing, even light, can escape from its event horizon, and, interestingly, Einstein didn't accept this viewpoint. Now, I'...
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Gravity's Rainbow: An accidental nominal similarity in science and literature?
There is an interesting extension of Einstein's Special Relativity, known as Doubly Special Relativity (presented after 2002) in which there is not only an observer-independent maximum velocity (i.e., ...
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Maxwell equations and aether
Were Maxwells equations (in their usual common form) assumed to be valid only in ether frame,in the past? If someone would ask them "In what frame are you writing these equations " ,what ...
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What is the history of adding the Clock Hypothesis to Special Relativity?
As far as I understand, Einstein’s original formulation of Special Relativity did not include the Clock Hypothesis, though it was implicitly assumed.
The modern formulation of SR adds a formal ...
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Books about the development/history of gravitational theory
I am looking for a book about the history of gravitational theory. It should obviously include discussions of Newton, Einstein, and their theories, and hopefully it would include the work of other ...
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Why did no one else, except Einstein, work on developing General Relativity between 1905-1915?
Einstein dedicated his time between 1905-1915 to develop general relativity (GR). It seems strange to me that no other physicists attempted to tackle this problem in this ten-year period. After all, ...
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Is Hermann Weyl's book “Space, Time, Matter” (1923) on General Relativity still relevant?
I really liked Hermann Weyl's mathematical books and would like to get accustomed to general relativity from his perspective, but wonder if it's still relevant after almost 100 (!) years?
Can this ...
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Did Arthur Schuster anticipate the equivalence between matter and energy in his speculations about antimatter?
Here Schuster apparently discussed matter and antimatter annihilating each other.
Had anyone suggested before this that matter could be transformed into energy?
(If indeed that is what is implied by ...
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Different versions of mass during early years of special relativity
My question is basically about four different versions of mass from the early years of special relativity when the concept of relativistic mass was acceptable. I'd appreciate it if you try to keep ...
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Why did energy-momentum relationship have to wait until 1928 to be established?
This web page shows how to derive energy-momentum relationship, $E_{total}^2=p^{2}c^{2}+\left( mc^{2}\right) ^{2}$, given the following equations. Please note that some sources make a distinction ...
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Einstein: 'SR is a theory of invariants, not relativity' -- source?
It is occasionally remarked that Einstein was unhappy that SR became referred to as a ‘theory of relativity’, when in his eyes it was, much more importantly, a theory of invariants (Invariantentheorie)...
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Were there doubts that Voigt's time dilation was correct rather than Einstein's?
According to Wikipedia's Voigt transformation:
Lorentz did not adopt this transformation, as he found in 1904 that
only the Lorentz contraction corresponds to the principle of
relativity. Since ...
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What is a spacetime continuum?
A very common expression I see in pop science is "the spacetime continuum". This expression isn't commonly used in modern discussions of general relativity, but looking at some older papers on the ...
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First paper introducing the concept of four-vectors
I'm trying to find the first paper in which the concept of four-vectors was introduced. I read "Principle of Relativity" by H. Minkowski but he only presents the notion of metric and invariant space-...
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Were Christoffel symbols used by Riemann?
The answer to the question would appear to be "no" looking at the transcription of Riemann's 1854 Ueber die Hypothesen, welche der Geometrie zu Grunde liegen lecture. However, Bernhard Riemann (1826-...
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What was the original reason physicists first believed that light must follow a geodesic?
Context: One of the key reasons Einstein first suspected space is curved by mass is due to the falling elevator thought experiment. This experiment implies that mass must curve the path of a light ray....
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Einstein praising Sophus Lie
p. 153 of
Raúl M. Falcón Ganfornina and Juan Núñez Valdés, “Mathematical Foundations of Santilli Isotopies,” trans. Alan Aversa, Algebras, Groups, and Geometries 32 (2015): 135–308.
quotes (but does ...
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What was the chain of theories that led to relativity? [closed]
Can you briefly sketch the sequence of math theories that were necessary for Einstein to figure out a convincing background for relativity?
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What was the relationship between Einstein and Minkowski?
I read many Einstein's Biographies, but Minkowski was never mentioned, though his discovery of the union of space and time created the basis for GR.
Minkowski was Einstein's teacher of mathematics ...
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Is it true Einstein doubted relativity near the end of his life?
Heard he wrote a bunch of rambling thoughts near the end of his life and doubted his own theory of relativity...it was in Einstein: His Life and Universe by Walter Isaacson
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Bainbridge's test of mass-energy equivalence
Kenneth Bainbridge was an early pioneer of mass spectroscopy. The Wikipedia article about him says:
He used this instrument to verify Albert Einstein's mass-energy equivalence, E = mc2
with a ...
user466
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How did Maxwell fall short of Einstein?
This source (I believe it's in Ukrainian) claims that Maxwell came very close to creating the relativity theory, however, it was the fact that he was adhering to the traditional scientific frame of ...
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Did Einstein want to reduce general relativity to elementary mathematics?
In this recent article, the authors write
Consequently, it is a desideratum to teach general relativity in a way
that is based on elementary mathematics only. This objective, already
stated by ...
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Did Galileo state the principle of equivalence in full generality?
The weak equivalence principle (WEP) is often attributed to Galileo. Did Galileo ever state the WEP precisely? For instance as given here?
The original principle, usually attributed to Galileo, ...
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General Relativity, General Covariance and Equivalence Principle
Einstein realized that uniform acceleration is indistinguishable from a homogeneous gravitational field (the principle of equivalence) through the Einstein Elevator thought experiment.
From the ...
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