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dd19ebc
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In the world of the very small, where particle and wave aspects of reality are equally significant, things do not behave in any way that we can understand from our experience of the everyday world...all pictures are false, and there is no physical analogy we can make to understand what goes on inside atoms. Atoms behave like atoms, nothing else.
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discovery
science
life
particles
understanding-the-world
quantum-mechanics
quantum-physics
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John Gribbin |
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d2a1772
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the best things in science are both beautiful and simple, a fact that all too many teacher conceal from their students, by accident or design.
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John Gribbin |
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06e8cc2
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true story of quantum mechanics, a truth far stranger than any fiction.
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John Gribbin |
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09e42db
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Nothing is real unless it is observed
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John Gribbin |
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b4fa075
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It isn't just that Bohr's atom with its electron "orbits" is a false picture; all pictures are false, and there is no physical analogy we can make to understand what goes on inside atoms. Atoms behave like atoms, nothing else."
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John Gribbin |
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22be864
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Sir Arthur Eddington summed up the situation brilliantly in his book The Nature of the Physical World, published in 1929. "No familiar conceptions can be woven around the electron," he said, and our best description of the atom boils down to "something unknown is doing we don't know what"."
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John Gribbin |
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70bc41b
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there is no underlying reality to the world. "Reality," in the everyday sense, is not a good way to think about the behavior of the fundamental particles that make up the universe; yet at the same time those particles seem to be inseparably connected into some invisible whole, each aware of what happens to the others."
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John Gribbin |
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6141bfb
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From this", says Schrodinger, "I learned many things, but not religion." His favourite question was, "Sir, do you really believe that?"
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John Gribbin |
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6dc7b88
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lqywd lmHdaWd@ 'mr kmn fy nmdhjn w fy tSwrn lbshry, l'nn nHwl 'n nSf shyy'an, hw kkl l yshbh 'y shy mm nkhbrh bHwsn. ltshwysh ldhy nsh`r bh `ndm nHwl tSwr kyf 'n lDw ymknh 'n ykwn m`an mwj@ w jsyman, hw jz mm ysmyh rytshrd fynmn lfyzyy'y l'mryky b'nh "n`ks lrGb@ Gyr mHkwm@, w n knt mtGTrs@, fy 'n nr~ l'mr blG@ mn shy m'lwf"."
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John Gribbin |
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b7aadb1
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It is better to debate a question without settling it than to settle a question without debating it.
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John Gribbin |
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6787459
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If the business of physics is ever finished, the world will be a much less interesting place in which to live . . .
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science
quantum-mechanics
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John Gribbin |
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525d66a
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Une with diffraction, just as if we let a thousand
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John Gribbin |
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3a41748
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At one point, Einstein had commented: 'It is quite wrong to try founding a theory on observable magnitudes alone. In reality the very opposite happens. It is the theory which decides what we can observe.
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John Gribbin |
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c8a6398
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According to the Copenhagen Interpretation, when an electron is ejected from an electron 'gun' on one side of the experiment it leaves as a particle, and can be detected as a particle. But it immediately dissolves into a probability wave, which travels through both of the holes and interferes with itself to make a pattern of probability on the other side of the holes. At the detector screen, the electron can appear as a particle at any poin..
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John Gribbin |
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428afeb
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Heisenberg's uncertainty relation measures the amount by which the complementary descriptions of the electron, or other fundamental entities, overlap. Position is very much a particle property - particles can be located precisely. Waves, on the other hand, have no precise location, but they do have momentum. The more you know about the wave aspect of reality, the less you know about the particle, and vice versa. Experiments designed to dete..
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quantum-mechanics
quantum-physics
quantum-theory
physics
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John Gribbin |
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b674383
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Earth as our home in space, a single blue-white oasis of life surrounded by a black desert.
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John Gribbin |
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c284b8c
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Motion in space can proceed in any direction and back again. Motion in time only proceeds in one direction in the everyday world, whatever seems to be going on at the particle level. It's hard to visualize the four dimensions of spacetime, each at right angles to the other, but we can leave out one dimension and imagine what this strict rule would mean if it applied to one of the three dimensions we are used to. It's as if we were allowed t..
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John Gribbin |
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3a650ed
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in 1906, ill and depressed, unhappy about the continuing opposition of many leading scientists to this kinetic theory of gases, he killed himself,
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John Gribbin |
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1cc5e2c
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whole universe can be thought of as a delayed-choice experiment in which the existence of observers who notice what is going on is what imparts tangible reality to the origin of everything. Following
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John Gribbin |
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150e7c4
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The image that emerges from quantum physics is similar in some ways to the way that the illusion that air, or water is a continuous fluid emerges. Myriad tiny particles separated by tiny gaps feels to you like a smooth fluid. Myriad quantum states separated by tiny gaps feels to you like a smooth flow of time. Zeno was right. The arrow of time points, but it does not move. THE
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John Gribbin |
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b973be9
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The theoretical understanding of what was going on was developed in the last quarter of the nineteenth century using statistical mechanics -an approach to thermodynamics that is based on applying the laws of statistics to the behaviour of large numbers of particles, such as the huge number of atoms or molecules present in a box of gas, each of them acting in accordance with Newton's laws.
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John Gribbin |
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9e83dbd
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The natural effect of processes going on in the Universe is to move from a state of order to a state of disorder, unless there is an input of energy from outside
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John Gribbin |
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2145a0e
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Curiously, though, we only have to look at one of the two slits for the outcome of the whole experiment to be affected, as if the electrons passing through the other slit also knew what we were doing. This is an example of quantum "non-locality," which means that what happens in one location seems to affect events in another location instantly. Non-locality is a key feature of the central mystery of quantum mechanics, and a vital ingredient..
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John Gribbin |
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8597103
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As I understood it, what really mattered was simply that some systems ('system' is just a jargon word for anything, like a swinging pendulum, or the Solar System, or water dripping from a tap) are very sensitive to their starting conditions, so that a tiny difference in the initial 'push' you give them causes a big difference in where they end up, and there is feedback, so that what a system does affects its own behaviour.
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John Gribbin |
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0a933f4
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It is a capital mistake to theorise before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts.
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John Gribbin |
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0fb9673
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A black hole with the mass of the Sun would take 1066 years for this to occur, even if it never swallowed any outside matter along the way. A black hole with the mass of a galaxy will evaporate in 1099 years, and even a hole containing the mass of a supercluster of galaxies - the biggest ever likely to form - will be gone in 10117 years. That
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John Gribbin |
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6f95881
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Reality' is the idea that there is a real world that exists whether or not anyone is looking at it, or measuring it.
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John Gribbin |
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a069ab6
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People like us, who believe in physics, know that the distinction between past, present and future is only a stubbornly persistent illusion. Einstein
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John Gribbin |
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71772f1
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it is not the way of science to sit idly back and hope that someone will come up with a "better" answer to our problems. In the absence of a better answer, we have to face up to the implications of the best answer we've got."
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John Gribbin |
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82ff9a6
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The existence of life must be considered as an elementary fact that cannot be explained, but must be taken as a starting point in biology, in a similar way as the quantum of action, which appears as an irrational element from the point of view of classical mechanical physics, taken together with the existence of elementary particles, forms the foundation of atomic physics. The asserted impossibility of a physical or chemical explanation of ..
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John Gribbin |
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ae101ec
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These examples both demonstrate that the laws of physics, notably Newton's laws, are time-reversible. They work just as well backwards in time as forwards, and there is no place in them for the second law of thermodynamics. The fundamental laws of physics do not distinguish between past and future.
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John Gribbin |
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afe29ae
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The Big Bang was not the beginning of the Universe.
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John Gribbin |
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ab1b1a8
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action, and there are also structures so distinct from the rest of the cell 'jelly', like cells within cells, that the best explanation of their presence is that that is indeed what they are. These semi-autonomous 'cells within the cell' are called organelles. As we saw in Chapter Four, Lynn Margulis has explained how the ancestors of the organelles used to be separate, bacteria
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John Gribbin |
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4ab246d
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El destino al que esta abocado cualquier especialista de cualquier area de la ciencia es cenirse cada vez mas estrechamente al tema de su especialidad, aprendiendo cada vez mas sobre cada vez menos materia, hasta acabar finalmente sabiendolo todo sobre nada.
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John Gribbin |
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dd9ee65
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spacetime is flat, that about 5 per cent of the mass of the Universe is in the form of baryons (including bright stars and gas and dust), some 27 per cent is in the form of cold dark matter, and 68 per cent is in the form of the lambda field, also known as dark energy.
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John Gribbin |
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70fa010
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Every problem in quantum physics had to be first "solved" using classical physics, and then be reworked by the judicious insertion of quantum numbers more by inspired guesswork than cool reasoning."
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John Gribbin |
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8c958c7
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Poincare took Laplace's argument to its logical conclusion. He proved, using the full rigour of mathematics, that if you have a box of gas containing a definite number of particles (as many as you like, as long as it is not actually infinite) and the particles strictly obey Newton's laws of motion, then after a sufficiently long interval of time the distribution of the particles in the box must return to its original state, with each partic..
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John Gribbin |
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56ba0b4
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Absolute, true, and mathematical time, for itself, and from its own nature flows equably without regard to anything external, and by another name is called duration: relative, apparent, and common time, is some sensible and external (whether accurate or unequable) measure for duration by means of motion, which is commonly used instead of true time; such as an hour, a day, a month, a year.
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John Gribbin |