Find science on or your birthday

Today in Science History - Quickie Quiz
Who said: “The path towards sustainable energy sources will be long and sometimes difficult. But America cannot resist this transition, we must lead it... That is how we will preserve our planet, commanded to our care by God. That’s what will lend meaning to the creed our fathers once declared.”
more quiz questions >>
Home > Category Index for Science Quotations > Category Index I > Category: Interference

Interference Quotes (8 quotes)

At times the [radio telescope] records exhibited a feature characteristic of interference, occurring some time later than the passage of the two known sources. This intermittent feature was curious, and I recall saying once that we would have to investigate the origin of that interference some day. We joked that it was probably due to the faulty ignition of some farm hand returning from a date.
From address to the 101st Meeting of the American Astronomical Society, Gainesville, Florida (27 Dec 1958). Printed in 'An Account of the Discovery of Jupiter as a Radio Source', The Astronomical Journal (Mar 1959), 64, No. 2, 37.
Science quotes on:  |  Characteristic (42)  |  Curious (11)  |  Date (6)  |  Farm (5)  |  Faulty (2)  |  Hand (51)  |  Ignition (2)  |  Investigation (104)  |  Origin (44)  |  Radio Telescope (5)  |  Record (33)  |  Returning (2)  |  Source (41)

Exper. I. I made a small hole in a window-shutter, and covered it with a piece of thick paper, which I perforated with a fine needle. For greater convenience of observation I placed a small looking-glass without the window-shutter, in such a position as to reflect the sun's light, in a direction nearly horizontal, upon the opposite wall, and to cause the cone of diverging light to pass over a table on which were several little screens of card-paper. I brought into the sunbeam a slip of card, about one-thirtieth of an inch in breadth, and observed its shadow, either on the wall or on other cards held at different distances. Besides the fringes of colour on each side of the shadow, the shadow itself was divided by similar parallel fringes, of smaller dimensions, differing in number, according to the distance at which the shadow was observed, but leaving the middle of the shadow always white. Now these fringes were the joint effects of the portions of light passing on each side of the slip of card and inflected, or rather diffracted, into the shadow. For, a little screen being placed a few inches from the card, so as to receive either edge of the shadow on its margin, all the fringes which had before been observed in the shadow on the wall, immediately disappeared, although the light inflected on the other side was allowed to retain its course, and although this light must have undergone any modification that the proximity of the other edge of the slip of card might have been capable of occasioning... Nor was it for want of a sufficient intensity of light that one of the two portions was incapable of producing the fringes alone; for when they were both uninterrupted, the lines appeared, even if the intensity was reduced to one-tenth or one-twentieth.
'Experiments and Calculations Relative to Physical Optics' (read in 1803), Philosophical Transactions (1804), 94, 2-3.
Science quotes on:  |  Experiment (412)  |  Fringe (3)  |  Hole (6)  |  Intensity (15)  |  Light (135)  |  Observation (293)  |  Reflection (30)  |  Screen (5)  |  Shadow (19)  |  Sunbeam (2)

In the dog two conditions were found to produce pathological disturbances by functional interference, namely, an unusually acute clashing of the excitatory and inhibitory processes, and the influence of strong and extraordinary stimuli. In man precisely similar conditions constitute the usual causes of nervous and psychic disturbances. Different conditions productive of extreme excitation, such as intense grief or bitter insults, often lead, when the natural reactions are inhibited by the necessary restraint, to profound and prolonged loss of balance in nervous and psychic activity.
Ivan Pavlov and G. V. Anrep (ed., trans.), Conditioned Reflexes—An Investigation of the Physiological Activity of the Cerebral Cortex (1927), 397.
Science quotes on:  |  Acuteness (2)  |  Balance (26)  |  Bitterness (2)  |  Cause (148)  |  Clash (4)  |  Condition (78)  |  Constitution (18)  |  Difference (142)  |  Disturbance (12)  |  Dog (24)  |  Excitation (6)  |  Experiment (412)  |  Extreme (20)  |  Function (47)  |  Grief (3)  |  Inhibition (10)  |  Insult (2)  |  Intensity (15)  |  Loss (50)  |  Man (270)  |  Necessity (89)  |  Nervousness (2)  |  Pathology (9)  |  Production (77)  |  Profoundness (2)  |  Prolong (7)  |  Psychology (72)  |  Reaction (49)  |  Restraint (4)  |  Similarity (15)  |  Stimulus (6)  |  Unusual (7)

It did not cause anxiety that Maxwell’s equations did not apply to gravitation, since nobody expected to find any link between electricity and gravitation at that particular level. But now physics was faced with an entirely new situation. The same entity, light, was at once a wave and a particle. How could one possibly imagine its proper size and shape? To produce interference it must be spread out, but to bounce off electrons it must be minutely localized. This was a fundamental dilemma, and the stalemate in the wave-photon battle meant that it must remain an enigma to trouble the soul of every true physicist. It was intolerable that light should be two such contradictory things. It was against all the ideals and traditions of science to harbor such an unresolved dualism gnawing at its vital parts. Yet the evidence on either side could not be denied, and much water was to flow beneath the bridges before a way out of the quandary was to be found. The way out came as a result of a brilliant counterattack initiated by the wave theory, but to tell of this now would spoil the whole story. It is well that the reader should appreciate through personal experience the agony of the physicists of the period. They could but make the best of it, and went around with woebegone faces sadly complaining that on Mondays, Wednesdays, and Fridays they must look on light as a wave; on Tuesdays, Thursdays, and Saturdays, as a particle. On Sundays they simply prayed.
The Strange Story of the Quantum (1947), 42.
Science quotes on:  |  Electron (45)  |  Light (135)  |  James Clerk Maxwell (65)  |  Quantum Theory (36)  |  Wave (36)

My practice as a scientist is atheistic. That is to say, when I set up an experiment I assume that no god, angel or devil is going to interfere with its course; and this assumption has been justified by such success as I have achieved in my professional career. I should therefore be intellectually dishonest if I were not also atheistic in the affairs of the world.
In Fact and Faith (1934), vi.
Science quotes on:  |  Achievement (80)  |  Affair (11)  |  Angel (10)  |  Assumption (29)  |  Atheist (6)  |  Career (34)  |  Course (32)  |  Devil (9)  |  Dishonesty (6)  |  Experiment (412)  |  God (246)  |  Intellect (116)  |  Justification (24)  |  Practice (28)  |  Profession (34)  |  Science And Religion (173)  |  Scientist (274)  |  Success (125)  |  Word (110)

Suppose a number of equal waves of water to move upon the surface of a stagnant lake, with a certain constant velocity, and to enter a narrow channel leading out of the lake. Suppose then another similar cause to have excited another equal series of waves, which arrive at the same time, with the first. Neither series of waves will destroy the other, but their effects will be combined: if they enter the channel in such a manner that the elevations of one series coincide with those of the other, they must together produce a series of greater joint elevations; but if the elevations of one series are so situated as to correspond to the depressions of the other, they must exactly fill up those depressions. And the surface of the water must remain smooth; at least I can discover no alternative, either from theory or from experiment.
A Reply to the Animadversions of the Edinburgh Reviewers on Some Papers Published in the Philosophical Transactions (1804), 17-8.
Science quotes on:  |  Alternative (11)  |  Channel (7)  |  Coincidence (7)  |  Combination (41)  |  Constant (19)  |  Depression (9)  |  Destruction (59)  |  Elevation (4)  |  Experiment (412)  |  Greater (20)  |  Lake (6)  |  Narrow (13)  |  Smooth (8)  |  Stagnant (2)  |  Supposition (28)  |  Surface (42)  |  Theory (397)  |  Velocity (6)  |  Water (142)  |  Wave (36)

The first [quality] to be named must always be the power of attention, of giving one's whole mind to the patient without the interposition of anything of oneself. It sounds simple but only the very greatest doctors ever fully attain it. ... The second thing to be striven for is intuition. This sounds an impossibility, for who can control that small quiet monitor? But intuition is only interference from experience stored and not actively recalled. ... The last aptitude I shall mention that must be attained by the good physician is that of handling the sick man's mind.
In The Collected Papers of Wilfred Trotter, FRS (1941), 98.
Science quotes on:  |  Activity (53)  |  Aptitude (7)  |  Attainment (26)  |  Attention (41)  |  Control (46)  |  Doctor (57)  |  Experience (151)  |  Greatness (26)  |  Handling (4)  |  Impossibility (39)  |  Interposition (2)  |  Intuition (26)  |  Mention (6)  |  Mind (307)  |  Monitor (2)  |  Patient (61)  |  Physician (179)  |  Quality (33)  |  Recall (3)  |  Sickness (16)  |  Simplicity (97)  |  Store (9)  |  Strive (9)

With crystals we are in a situation similar to an attempt to investigate an optical grating merely from the spectra it produces... But a knowledge of the positions and intensities of the spectra does not suffice for the determination of the structure. The phases with which the diffracted waves vibrate relative to one another enter in an essential way. To determine a crystal structure on the atomic scale, one must know the phase differences between the different interference spots on the photographic plate, and this task may certainly prove to be rather difficult.
Physikalische Zeitschrift (1913), 14. Translated in Walter Moore, Schrödinger. Life and Thought (1989), 73.
Science quotes on:  |  Atom (170)  |  Crystal (25)  |  Determination (43)  |  Diffraction (3)  |  Intensity (15)  |  Investigation (104)  |  Knowledge (749)  |  Phase (8)  |  Photograph (14)  |  Position (18)  |  Scale (28)  |  Spectrum (17)  |  Structure (111)  |  Wave (36)

Carl Sagan Thumbnail In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. (1987) -- Carl Sagan
Quotations by: • Albert Einstein • Isaac Newton • Lord Kelvin • Charles Darwin • Srinivasa Ramanujan • Carl Sagan • Florence Nightingale • Thomas Edison • Aristotle • Marie Curie • Benjamin Franklin • Winston Churchill • Galileo Galilei • Sigmund Freud • Robert Bunsen • Louis Pasteur • Theodore Roosevelt • Abraham Lincoln • Ronald Reagan • Leonardo DaVinci • Michio Kaku • Karl Popper • Johann Goethe • Robert Oppenheimer • Charles Kettering  ... (more people)

Quotations about: • Atomic  Bomb • Biology • Chemistry • Deforestation • Engineering • Anatomy • Astronomy • Bacteria • Biochemistry • Botany • Conservation • Dinosaur • Environment • Fractal • Genetics • Geology • History of Science • Invention • Jupiter • Knowledge • Love • Mathematics • Measurement • Medicine • Natural Resource • Organic Chemistry • Physics • Physician • Quantum Theory • Research • Science and Art • Teacher • Technology • Universe • Volcano • Virus • Wind Power • Women Scientists • X-Rays • Youth • Zoology  ... (more topics)
Sitewide search within all Today In Science History pages:
Custom Quotations Search - custom search within only our quotations pages:
Visit our Science and Scientist Quotations index for more Science Quotes from archaeologists, biologists, chemists, geologists, inventors and inventions, mathematicians, physicists, pioneers in medicine, science events and technology.

Names index: | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |

Categories index: | 1 | 2 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |

who invites your feedback

- 100 -
Sophie Germain
Gertrude Elion
Ernest Rutherford
James Chadwick
Marcel Proust
William Harvey
Johann Goethe
John Keynes
Carl Gauss
Paul Feyerabend
- 90 -
Antoine Lavoisier
Lise Meitner
Charles Babbage
Ibn Khaldun
Ralph Emerson
Robert Bunsen
Frederick Banting
Andre Ampere
Winston Churchill
- 80 -
John Locke
Bronislaw Malinowski
Thomas Huxley
Alessandro Volta
Erwin Schrodinger
Wilhelm Roentgen
Louis Pasteur
Bertrand Russell
Jean Lamarck
- 70 -
Samuel Morse
John Wheeler
Nicolaus Copernicus
Robert Fulton
Pierre Laplace
Humphry Davy
Thomas Edison
Lord Kelvin
Theodore Roosevelt
Carolus Linnaeus
- 60 -
Francis Galton
Linus Pauling
Immanuel Kant
Martin Fischer
Robert Boyle
Karl Popper
Paul Dirac
James Watson
William Shakespeare
- 50 -
Stephen Hawking
Niels Bohr
Nikola Tesla
Rachel Carson
Max Planck
Henry Adams
Richard Dawkins
Werner Heisenberg
Alfred Wegener
John Dalton
- 40 -
Pierre Fermat
Edward Wilson
Johannes Kepler
Gustave Eiffel
Giordano Bruno
JJ Thomson
Thomas Kuhn
Leonardo DaVinci
David Hume
- 30 -
Andreas Vesalius
Rudolf Virchow
Richard Feynman
James Hutton
Alexander Fleming
Emile Durkheim
Benjamin Franklin
Robert Oppenheimer
Robert Hooke
Charles Kettering
- 20 -
Carl Sagan
James Maxwell
Marie Curie
Rene Descartes
Francis Crick
Michael Faraday
Srinivasa Ramanujan
Francis Bacon
Galileo Galilei
- 10 -
John Watson
Rosalind Franklin
Michio Kaku
Isaac Asimov
Charles Darwin
Sigmund Freud
Albert Einstein
Florence Nightingale
Isaac Newton

Thank you for sharing.
Today in Science History
Sign up for Newsletter
with quiz, quotes and more.