Quotes from Henning Genz

Of all the material objects we know, quasars are closest to lucretius's javelin. Quasars are galaxies in early stage of evolution. The light that tells us about them today has traveled for billions of years. They move away from us at a speed close to that of light; in that way they mirror the expansion of the universe.

All in all, we come to the conclusion that no more than 1 percent of all matter in the universe falls in the visible category.

Charged particles can scatter light by absorbing and reemitting it (a). Light can scatter off light only by the mediation of charged particles-the virtual particle-antiparticle pairs fluctuating in the vacuum (b). This effect is very small; there is no experimental proof yet.

Particle-antiparticle pairs fluctuating in the vacuum also permit the fusion of two real photons into a single one, in the presence of an external field.

We know there is a conservation law for electric charge; this simply means that the sum of these charges in any process remains constant. If a positive charge pops out of the vacuum, a negative one must accompany it, to keep the overall charge zero, as the vacuum demands. To the best of our knowledge the sum of all charges in the universe is zero-and so it must have been from its origin.

Chaotic or disordered distributions are symmetrical on the average. An observer cannot conclude anything about his location from looking around him. An example is the chaotic disposition of sand grains at the beach, or of flecks of light on a television screen when the station closes down. In the chaotic distribution, no location or direction is preferred. Only when there is structure appearing in a chaotic distribution does orientation become possible, as the overall symmetry is broken.

What really transcends our understanding is the mechanism that permits these oscillations of abstract field quantities to carry energy. We know this is true; our relevant equations say so, and the solar energy collectors prove it. A photoelectric cell registers at this instant an energy that left the Sun, in the form of light, some eight minutes ago. Travelling across space, this light did not lose its energy; rather, it is part of the energetic excitations within empty space.

The photon itself, the carrier of the electromagnetic interaction, is electrically neutral. That means all interactions among photons proceed through the mediation of other, electrically charged particles.

In summary, there is nothing much to the conversion of energy into matter and vice versa. The first actual transformation of light into matter without the participation of other particles, accomplished in 1997, generated a huge response from the media. The technical problems encountered in order to achieve this goal were enormous-but there was nothing particularly new in the result itself. The same holds for the recent assembly of antimatter from antiparticles.

Second, what properties distinguish an otherwise empty volume that retains only some black-body radiation at zero temperature-dubbed zero-degree radiation-from truly empty space? We will show that one remarkable feature of zero-degree radiation is shared with empty space: An observer is unable to determine whether he is at rest or moving with constant speed with respect to it.

There is field for every particle. If that field is concentrated in some spatial region, the particle of that field is likely to be located in that region once a detector looks for it. We introduced fields as abstract quantities associated with space; we describe a field as an excitation of space that oscillates like tall grasses in a heavy wind. Recall, however, that there is no material aspect to these field oscillations. Rather, a field is a field is a field.

While the effective electrical charge of a proton decreases with distance, the strength of the effective color charge of a quark increases with distance.

Once the thermal radiation reaches the surface temperature of the Sun-some 6000 degrees Celsius-we perceive it as white light. At still higher temperatures, 8500 degrees Celsius, the light will be blue. Beyond this, thermal radiation passes into the X-ray range. And so it goes, ad infinitum: the higher the temperature, the higher the frequency of thermal radiation.

The uncertainty relation tells us that an infinitely large energy corresponds to infinitely small distances.

In general, the removal of energy from gravitationally bound systems accelerates the movement of their components. This also goes for systems whose components move about randomly: the faster their random motion, the higher their temperature. This means that the temperature of gravitationally bound systems increase as they give off energy.

Considering the energy balance, the reduction in size and the rise in temperature of the black hole form a feedback mechanism that ultimately must lead to its explosion: The more energy it radiates, the hotter it gets. The hotter it is, the more energy it radiates. And as its energy rises, the ultimate outcome is inescapable: The black hole must explode.