“E = mc2 really applies only to isolated bodies at rest. In general, when you have moving bodies, or interacting bodies, energy and mass aren't proportional. E = mc2 simply doesn't apply. …For moving bodies, the correct mass-energy equation is
E=\frac {mc^2} {\sqrt{1-\frac{v^2} {c^2}}}
where v is the velocity. For a body at rest (v=0), this becomes E = mc2. …we must consider the special case of particles with zero mass… examples include photons, color gluons, and gravitons. If we attempt to put m = 0 and v = c in our general mass-energy equation, both the numerator and denominator on the right-hand-side vanish, and we get the nonsensical relation E = 0/0. The correct result is that the energy of a photon can take any value. …The energy E of a photon is proportional to the frequency f of the light it represents. …they are related by the Planck-Einstein-Schrödinger equation E = hf, where h is Plank's constant.”

— Frank Wilczek

when the velocity <math>v</math> approaches the speed of light c, the denominator approaches 0 thus E approaches infinity, unless m = 0.
Source: The Lightness of Being – Mass, Ether and the Unification of Forces (2008), Ch. 3, p. 19 & Appendix A

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Frank Wilczek 49

physicist 1951

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“According to the Special Theory of Relativity, the velocity of a moving body is always less than the velocity of light. Since the energy of motion of a body depends on its inertial mass and its velocity, it follows that if the energy of a body is increased indefinitely by the continual application of a force, the inertial mass of the body must be increased too; for, if not, the velocity would ultimately increase indefinitely and exceed the velocity of light. Einstein found that, corresponding to any increase in the energy content of a body, there is an equivalent increase in its inertial mass. Mass and energy thus appeared to be different names for the same thing, the energy associated with a mass M being Mc2, where c is the velocity of light; and the mass M of a body moving with velocity v he found to be given by the following formulaM = \frac {m}{\sqrt{(1 - \frac {v^2}{c^2}}}</center”

Gerald James Whitrow (1912–2000) British mathematician

The Structure of the Universe: An Introduction to Cosmology (1949)

“Consider an event, for example the outburst if a nova… Suppose this event is observed from two stars in line with the nova, and suppose further that the two stars are moving uniformly with respect to each other in this line. Let the epoch at which these stars passed by each other be taken as the zero of time measurement, and let an observer A on one of the stars estimate the distance and epoch of the nova outburst to be x units of length and t units of time, respectively. Suppose the other star is moving toward the nova with velocity v relative to A. Let an observer B on the star estimate the distance and epoch of the nova outburst to be x' units of length and t' units of time, respectively. Then the Lorentz formulae, relating x' to t', arex' = \frac {x-vt}{\sqrt{1-\frac{v^2}{c^2}}}; \qquad t' = \frac {t-\frac{vx}{c^2}}{\sqrt{1-\frac{v^2}{c^2}}}
These formulae are… quite general, applying to any event in line with two uniformly moving observers. If we let c become infinite then the ratio of v to c tends to zero and the formulae becomex' = x - vt; \qquad t' = t.”

Gerald James Whitrow (1912–2000) British mathematician

p, 125
The Structure of the Universe: An Introduction to Cosmology (1949)

“Different ways of writing the same equation can suggest very different things, even if they are logically equivalent…. In Einstein's original 1905 paper, you do not find the equation E = mc2. What you find is m = E/c2…. the title of the paper is a question: "Does the Inertia of a Body Depend on Its Energy Content?" …If we can explain mass in terms of energy, we'll be improving our description of the world. We'll need fewer ingrediants in our world-recipe.”

Frank Wilczek (1951) physicist

Source: The Lightness of Being – Mass, Ether and the Unification of Forces (2008), Ch. 3, p. 19.

“In the work of Vieta the analytic methods replaced the geometric, and his solutions of the quadratic equation were therefore a distinct advance upon those of his predecessors. For example, to solve the equation x^2 + ax + b = 0 he placed u + z for x. He then hadu^2 + (2z + a)u +(z^2 + az + b) = 0.He now let 2z + a = 0, whence z = -\frac{1}{2}a,and this gaveu^2 - \frac{1}{4}(a^2 - 4b) = 0.
u = \pm \frac{1}{2} \sqrt{a^2 - 4b}.andx = u + z = -\frac{1}{2}a \pm \sqrt{a^2 - 4b}.</center”

David Eugene Smith (1860–1944) American mathematician

Source: History of Mathematics (1925) Vol.2, p.449

“The value of the intrinsic approach is especially apparent in considering 3-dimensional congruence spaces… The intrinsic geometry of such a space of curvature K provides formulae for the surface area S and the volume V of a "small sphere" of radius r, whose leading terms are 3)S = 4 \pi r^2 (1 - \frac{Kr^2}{3} + …),
V = \frac{4}{3} \pi r^3 (1 - \frac{Kr^2}{5} + …).”

Howard P. Robertson (1903–1961) American mathematician and physicist

Geometry as a Branch of Physics (1949)

“The solution of (1), which represents a homogeneous manifold, may be written in the form:ds^2 = \frac{d\rho^2}{1 - \kappa^2\rho^2} - \rho^2 (d\theta^2 + sin^2 \theta \; d\phi^2) + (1 - \kappa^2 \rho^2)\; c^2 d\tau^2, \qquad (2)where \kappa = \sqrt \frac{\lambda}{3}. If we consider \rho as determining distance from the origin… and \tau as measuring the proper-time of a clock at the origin, we are led to the de Sitter spherical world…”

Howard P. Robertson (1903–1961) American mathematician and physicist

"On Relativistic Cosmology" (1928)

“Measurements which may be made on the surface of the earth… is an example of a 2-dimensional congruence space of positive curvature K = \frac{1}{R^2}… [C]onsider… a "small circle" of radius r (measured on the surface!)… its perimeter L and area A… are clearly less than the corresponding measures 2\pi r and \pi r^2… in the Euclidean plane. …for sufficiently small r (i. e., small compared with R) these quantities on the sphere are given by 1):L = 2 \pi r (1 - \frac{Kr^2}{6} + …),
A = \pi r^2”

Howard P. Robertson (1903–1961) American mathematician and physicist

1 - \frac{Kr^2}{12} + …
Geometry as a Branch of Physics (1949)

“Motion with respect to the universal ocean of aether eludes us. We say, "Let V be the velocity of a body through the aether", and form the various electromagnetic equations in which V is scattered liberally. Then we insert the observed values, and try to eliminate everything which is unknown except V. The solution goes on famously; but just as we have got rid of all the other unknowns, behold! V disappears as well, and we are left with the indisputable but irritating conclusion —
::: 0 = 0
This is a favourite device that mathematical equations resort to, when we propound stupid questions.”

Arthur Stanley Eddington (1882–1944) British astrophysicist

Source: The Nature of the Physical World (1928), Ch. 2 Relativity

“The discovery of Hippocrates amounted to the discovery of the fact that from the relation
(1)\frac{a}{x} = \frac{x}{y} = \frac{y}{b}it follows that(\frac{a}{x})^3 = [\frac{a}{x} \cdot \frac{x}{y} \cdot \frac{y}{b} =] \frac{a}{b}and if a = 2b, [then (\frac{a}{x})^3 = 2, and]a^3 = 2x^3.The equations (1) are equivalent [by reducing to common denominators or cross multiplication] to the three equations
(2)x^2 = ay, y^2 = bx, xy = ab[or equivalently…y = \frac{x^2}{a}, x = \frac{y^2}{b}, y = \frac{ab}{x} ]Doubling the Cube
the 2 solutions of Menaechmusand the solutions of Menaechmus described by Eutocius amount to the determination of a point as the intersection of the curves represented in a rectangular system of Cartesian coordinates by any two of the equations (2).
Let AO, BO be straight lines placed so as to form a right angle at O, and of length a, b respectively. Produce BO to x and AO to y.
The first solution now consists in drawing a parabola, with vertex O and axis Ox, such that its parameter is equal to BO or b, and a hyperbola with Ox, Oy as asymptotes such that the rectangle under the distances of any point on the curve from Ox, Oy respectively is equal to the rectangle under AO, BO i. e. to ab. If P be the point of intersection of the parabola and hyperbola, and PN, PM be drawn perpendicular to Ox, Oy, i. e. if PN, PM be denoted by y, x, the coordinates of the point P, we shall have

\begin{cases}y^2 = b. ON = b. PM = bx\\ and\\ xy = PM. PN = ab\end{cases}whence\frac{a}{x} = \frac{x}{y} = \frac{y}{b}.
In the second solution of Menaechmus we are to draw the parabola described in the first solution and also the parabola whose vertex is O, axis Oy and parameter equal to a.”

Thomas Little Heath (1861–1940) British civil servant and academic

The point P where the two parabolas intersect is given by<center><math>\begin{cases}y^2 = bx\\x^2 = ay\end{cases}</math></center>whence, as before,<center><math>\frac{a}{x} = \frac{x}{y} = \frac{y}{b}.</math></center>
Apollonius of Perga (1896)

“If we have two spherical bodies of equal mass at a given distance from each other and insert a third spherical body of the same mass half way between the two we do not double the mass attraction between any two of the three. We increase the attraction by 2 to the second power which is 4.”

Buckminster Fuller (1895–1983) American architect, systems theorist, author, designer, inventor and futurist

Source: 1960s, Presentation to U.S. Congressional Sub-Committee on World Game (1969), p. 14
Context: I will give you one very simple example of synergy. All our metallic alloys are synergetic. We will examine chrome-nickel steel. The outstanding characteristic of metallic strength is its ability to cohere in one piece. We test the metals tensile strength per square inch of cross section of the tested sample. The very high number of pounds-per-square-inch tensile strength of chrome-nickel steel has changed our whole economy because it retained its structural integrity at so high a temperature as to make possible the jet engine which has halved the time it takes to fly around the world. The prime constituents are chromium, nickel, and iron. We will take the highest ultimate tensile strength of those three. The iron’s ultimate tensile strength is about 60,000 pounds per square inch. Nickel’s ultimate is about 80,000 p. s. i. Chromium is about 70,000 p. s. i. Ultimate tensile strengths of the other minor constituents: carbon, manganese, et cetera, added together total about 40,000 psi. If we use the same tensile logic as that applied to a chain and say that a chain is no stronger than its weakest link, then we would assume that chrome-nickel steel would part at between 40,000 and 60,000 p. s. i. But we find experimentally that is not the case. We find by test that chrome-nickel steel is 350,000 pounds a square inch which is 50 percent stronger than the sum of the strength of all its alloys. To prove so we add 60,000, 70,000 and 80,000 which comes to 210,000. To this we add the 40,000 of minor alloying constituents which brings the sum of the strengths of all its alloying to only 250,000 pounds a square inch. The explanation for this is Newton’s gravitational law which noted the experimentally proven fact that the relative mass attraction of one body for another is proportioned to the second power of the relative proximity of the two bodies as expressed in the relative diameters of the two bodies. If we have two spherical bodies of equal mass at a given distance from each other and insert a third spherical body of the same mass half way between the two we do not double the mass attraction between any two of the three. We increase the attraction by 2 to the second power which is 4. Halving the distance fourfolds the inter-mass attraction. When we bring a galaxy of iron atoms together with the chromium atoms and a galaxy of nickel atoms they all fit neatly between one another and bring about the multifolding of their intercoherency. But there is nothing in one body by itself that says that it will have mass attraction. This can only be discovered by experimenting with two and more bodies. And even then there is no explanation of why there must be mass attraction and why it should increase as the second power of the relative increase of proximity. That is synergy.

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Frank Wilczek 49

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