Quotes About Physics

Such thinking is sheer speculation, but the laws of physics allow for the possibility of opening a hole in space by concentrating enough energy at a single point, until we access the space-time foam and wormholes emerge connecting our universe to a baby universe.

According to Einstein, there is no gravitational pull. The earth warps the space-time continuum around our bodies, so space itself pushes us down to the floor. Thus, it is the presence of matter that warps space around it, giving us the illusion that there is a gravitational force pulling on neighboring objects.

Tachyons travel faster than light and have imaginary mass; it's not clear if they fall up or down under gravity. They, too, have not been found in the laboratory.)

Rotating in four-dimensional space unifies the concept of space and time, turning one into the other as the velocity is increased. This beautiful, elegant concept, that symmetry unifies seemingly dissimilar entities into a pleasing, harmonious whole, guided Einstein for the next fifty years.

in string theory, the dimensionality of space-time is fixed at ten dimensions.

After that cancellation [of the Superconducting Super Collider in Texas, after $2 billion had been spent on it], we physicists learned that we have to sing for our supper. ... The Cold War is over. You can't simply say "Russia!" to Congress, and they whip out their checkbook and say, "How much?" We have to tell the people why this atom-smasher is going to benefit their lives.

So string theory and M-theory are really the same theory, except that string theory is a reduction of eleven-dimensional M-theory to ten dimensions.)

This was the missing piece in the puzzle. The secret of wood that bound matter together was the Yang-Mills filed, not the geometry of Einstein. It appeared as though this, and not geometry, was the central lesson of physics.

Kip Thorne says, "By 2020, physicists will understand the laws of quantum gravity, which will be found to be a variant of string theory.

Second is N, equal to 1036, which is the strength of the electric force divided by the strength of gravity, which shows how weak gravity is.

Physicists believe that at the instant of the Big Bang, the universe was in perfect symmetry and there was an equal amount of matter and antimatter. If so, the annihilation between the two would have been perfect and complete, and the universe should be made of pure radiation. Yet here we are, made of matter, which should not be around anymore. Our very existence defies modern physics.

Riemann found that in four spatial dimensions, one needs a collection of ten numbers at each point to describe its properties.

Fourth is Lambda, the cosmological constant, which determines the acceleration of the universe.

Roughly speaking, the greater the value of the metric tensor, the greater the crumpling of the sheet. No mattet how crumpled the sheet of paper, the metric tensor gives us a simple means of measuring its curvature at any point. If we flattened the crumpled sheet completely, then we would retrieve the formula of Pythagoras.

Imagine fish swimming in a shallow pond, just below the lily pads, thinking that their "universe" is only two-dimensional. Our three-dimensional world may be beyond their ken. But there is a way in which they can detect the presence of the third dimension. If it rains, they can clearly see the shadows of ripples traveling along the surface of the pond. Similarly, we cannot see the fifth dimension, but ripples in the fifth dimension appear to us as light.

Water, for example, is a diamagnet. since all living things are made of water, they can levitate in the presence of a powerful magnetic field. In a magnetic field of about 15 teslas (30,000 times the Earth's field), scientists have levitated small animals, such as frogs. But if room-temperature superconductors become a reality, it should be possible to levitate large nonmagnetic objects as well, via their diamagnetic properties.

Cuando estamos sentados en una silla, creemos que la tocamos, pero en realidad estamos suspendidos sobre ella, flotando a menos de un nanometro sobre el asiento

If we now take a Kaluza-Klein theory defined in 4+N dimensions and then curl up N dimensions, we will find that the equations split into two pieces. The first piece is Einstein's usual equations, which we retrieve as expected. But the second piece will not be the theory of Maxwell. We find that the remainder is precisely the Yang-Mills theory, which forms the basis of all subatomic physics! This is the key to turning the symmetries of wood into the symmetries of marble.

When Einstein later complained that "God does not play dice with the world," Bohr reportedly fired back, "Stop telling God what to do.

If we are right, big bangs are taking place even as you read this sentence.

Nobel laureate Richard Feynman was fond of saying that no one really understands the quantum theory. Ironically, although the quantum theory is the most successful theory ever proposed by the human mind

To a physicist, beauty means symmetry and simplicity. If a theory is beautiful, this means it has a powerful symmetry that can explain a large body of data in the most compact, economical manner. More precisely, and equation is considered to be beautiful if it remains the same when we interchange its components among themselves.

Einstein's Cosmos

Finalmente, Einstein creó dos grandes teorías. La primera fue la relatividad especial, que describía las propiedades de los rayos de luz en el espacio-tiempo e introducía una simetría basada en rotaciones en cuatro dimensiones. La segunda fue la relatividad general, en la que la gravedad se revela como la curvatura del espacio-tiempo.