Antimatter properties

A recent development in nuclear medicine that illustrates how advances in basic research are transformed into practical applications is positron emission tomography or PET. PET creates a three-dimensional image of a body part using positron emitting isotopes. Positrons, positively charged electrons, are a form of antimatter. Antimatter consists of particles that have the same mass as ordinary matter, but differ in charge or some other property. For example, antipro-... 

Antimatter all particles having complementary properties of matter, for example, positrons... 

Sufficient atomic particle research has been accomplished to warrant discussion of possible methods of applying energy available from particle mass annihilation to rocket propulsion. Complete conversion of matter to energy would allow exhaust velocities near that of light to be obtained from a propulsion device. Antimatter, by definition is matter made up of antiparticles, such as antineutrons, negatrons (antiprotons), and positrons (anheledrons). An annihilation property is known to exist between particles with one particle termed the anhparticle of the other. 

Unique interface between matter and antimatter Whereas particles and antiparticles cannot coexist stably, Antiprotonic Helium is an exceptional case, where an intruder antiparticle (p) coexists with the normal matter (helium medium) for microseconds. Here, the property of the orbiting p (charge, mass, magnetic moment and other QED characteristics) can be probed. It is an interesting irony that the property of the proton cannot always be studied so precisely, because there is no atomic system in which a proton is orbiting. 

Abstract. CPT invariance is a fundamental property of quantum field theories in flat space-time. Principal consequences include the predictions that particles and their antiparticles have equal masses and lifetimes, and equal and opposite electric charges and magnetic moments. It also follows that the fine structure, hyperfine structure, and Lamb shifts of matter and antimatter bound systems should be identical. 

The equivalence principle is the cornerstone of general relativity. This principle states that the weight of any object is proportional to its inertial mass. This is quite amazing. A brick has an inherent property called its inertial mass the brick s weight, which is in direct proportion to its gravitational mass, is a measure of the gravitational attraction between it and the Earth. The equivalence principle asserts that these two masses, inertial and gravitational, are identical. Does antimatter obey the equivalence principle Simply put, physicists do not know. 

Physicists are very interested in comparing the properties of antihydrogen with those of hydrogen, especially to determine antimatter s response to gravity. However, these antiatoms, created in flight in the accelerator, lasted for a fleeting 40-billionths of a second, too short a time for the scientists to observe... 

Does it follow that there could be a world identical to this one in which matter and antimatter are switched and in which there is no consciousness That is conceivable in the sense that there is no contradiction or incoherence in its supposition, but perhaps it is not metaphysically possible. Note that if it is true, it does not show that consciousness is causally impotent in our world. For example, for many computational structures, there are computationally equivalent electronic and hydraulic implementations. But it would be a mistake to conclude that the electrical properties or the hydraulic properties do not do anything significant (Block, 1980a). They have parallel causal efficacies. 

In the past few decades a new method for the examination of matter has developed from the study of positron annihilation. This method utilizes the interaction of matter and the antielectron, i.e., the positron, one of the elementary particles of antimatter most readily accessible under terrestrial conditions. Positron annihilation reacts sensitively to changes occurring in the physical and (as a consequence of the formation of positronium atoms, which behave as chemical elements) the chemical properties of the medium. 

Antimatter All particles known to us have antiparticles, with opposite properties in all measures, such as charge. 

Antimatter. All known particles have antiparticles, with opposite properties in all measures, such as charge. The collision of a particle and its antiparticle always leads to a burst of radiation, when both particles are annihilated. In cosmic rays we observe antiprotons, and positrons, the antiparticles to electrons. The search for antinuclei has not been successful any detection of even a single antinucleus, such as antihelium, would provide extremely strong constraints on the physics of matter in the universe. 

---