# „Some of the effects predicted by the theory [of loop quantum gravity] appear to be in conflict with one of the principles of Einstein's special theory of relativity... that the speed of light is a universal constant.... Photons of higher energy travel slightly slower than low-energy photons.... the principle of [general] relativity is preserved but Einstein's special theory of relativity requires modification.... A photon can have an energy-dependent speed without violating the principle of [general] relativity!“

## Citas similares

### „Einstein's theory of relativity“

— Hermann Weyl German mathematician 1885 - 1955

Context: Einstein's theory of relativity has advanced our ideas of the structure of the cosmos a step further. It is as if a wall which separated us from Truth has collapsed. Wider expanses and greater depths are now exposed to the searching eye of knowledge, regions of which we had not even a presentiment. It has brought us much nearer to grasping the plan that underlies all physical happening.
From the Author's Preface to First Edition (1918)

### „The miracle of physics that I'm talking about here is something that was actually known since the time of Einstein's general relativity; that gravity is not always attractive. Gravity can act repulsively. Einstein introduced this in 1916... in the form of the cosmological constant, and the original motivation of modifying the equations of general relativity to allow this was because Einstein thought that the universe was static, and he realized that ordinary gravity would cause the universe to collapse if it was static.... The fact that general relativity can support this gravitational repulsion, still being consistent with all the principles that general relativity incorporates, is the important thing which Einstein himself did discover..“

— Alan Guth American theoretical physicist and cosmologist 1947

Lecture 1: Inflationary Cosmology: Is Our Universe Part of a Multiverse? Part I.

### „One of the evident facts about the world is the stability of empty space-time. In classical general relativity we can explain this as a consequence of the positive energy theorem... the positive energy theorem must extend in some suitable form to any viable quantum theory of gravity.“

— Lee Smolin American cosmologist 1955

### „Jesus could not have imagined such an idea as Albert Einstein's theory of relativity.“

— John Shelby Spong American bishop 1931

p. 25

### „Relativity theory forced the abandonment, in principle, of absolute space and absolute time.“

— Marshall McLuhan Canadian educator, philosopher, and scholar-- a professor of English literature, a literary critic, and a communicat... 1918 - 1980

p. 43

### „If grand unified theories are correct, we ought to be able to derive the relative power of the strong, weak, and electromagnetic interactions at accessible energies from their presumed equality at much higher energies. When this is attempted, a wonderful result emerges.... in the form first calculated by Howard Georgi, Helen Quinn, and Steven Weinberg... The couplings of strong-interaction gluons decrease, those of the [weak interaction] W bosons stay roughly constant, and those of the [electromagnetic interaction] photons increase at short distances [or high energies]—so they all tend to converge, as desired.“

— Frank Wilczek physicist 1951

### „A new development began for relativity theory after 1925 with its absorption into quantum physics. The first great success was scored by Dirac's quantum mechanical equations of the electron, which introduced a new sort of quantities, the spinors, besides the vectors and tensors into our physical theories.... But difficulties of the gravest kind turned up when one passed from one electron or photon to the interaction among an indeterminate number of such particles. In spite of several advances a final solution of this problem is not yet in sight and may well require a deep modification of the foundation of quantum mechanics, such as would account in the same basic manner for the elementary electric charge e as relativity theory and our present quantum mechanics account for c and h.“

— Hermann Weyl German mathematician 1885 - 1955

Preface to the First American Printing (1950) Note: see Paul Dirac, The Principles of Quantum Mechanics (1947)

### „General relativity is certainly a very beautiful theory, but how does one judge the elegance of physical theories generally?“

— Roger Penrose English mathematical physicist, recreational mathematician and philosopher 1931

Ch. 1, Mathematical Elegance as a Driving Force, p. 7 https://books.google.com/books?id=T09kCwAAQBAJ&pg=PA7.

### „String theory at its finest is, or should be, a new branch of geometry. ...I, myself, believe rather strongly that the proper setting for string theory will prove to be a suitable elaboration of the geometrical ideas upon which Einstein based general relativity.“

— Edward Witten American theoretical physicist 1951

Context: String theory at its finest is, or should be, a new branch of geometry.... I, myself, believe rather strongly that the proper setting for string theory will prove to be a suitable elaboration of the geometrical ideas upon which Einstein based general relativity.
"Edward Witten" interview, Superstrings: A Theory of Everything? (1992) ed. P.C.W. Davies, Julian Brown

### „It is almost impossible to have a baseless snobbish opinion of the General Theory of Relativity.“

— Michael Moorcock English writer, editor, critic 1939

Fantastic Metropolis, Christmas Editorial (http://www.fantasticmetropolis.com/i/20011209/3/)

### „Although the Special Theory of Relativity does not account for electromagnetic phenomena, it explains many of their properties. General Relativity, however, tells us nothing about electromagnetism. In Einstein's space-time continuum gravitational forces are absorbed in the geometry, but the electromagnetic forces are quite unaffected. Various attempts have been made to generate the geometry of space-time so as to produce a unified field theory incorporating both gravitational and electromagnetic forces.“

— Gerald James Whitrow British mathematician 1912 - 2000

p, 125