Re: Storms question about the induced field
Edmund Storms writes: I ask how a structure can form when the time needed for one part to sense the characteristics of another part takes millions of years to be communicated? How does a star at one side of a galaxy know that its gravity and momentum are being exactly balanced by a star on the other side when this information takes a million years to pass between the two stars. My guess is that the structure is formed when the stars are close together at the center of the galaxy. The shape usually remains as it was when they drift apart, because nothing disrupts it. In some cases, galaxies have been disrupted by collisions with other galaxies, I believe. Galaxies group together to form even larger structures. Presumably this structure reflects conditions soon after the Big Bang, when everything was close together. - Jed
Re: Storms question about the induced field
I mean to add . . . Edmund Storms writes: How does a star at one side of a galaxy know that its gravity and momentum are being exactly balanced by a star on the other side when this information takes a million years to pass between the two stars. Do we know that it balances exactly? Perhaps close examination would reveal that the balance propagates at the speed of light. I suppose it might be difficult to tell the difference in many cases. Perhaps you could see it in effects from other, nearby or impinging galaxies. - Jed
Storms question about the induced field
The induced field is not superluminal. Take the electric force for example. The force between two charges is equal and opposite. The system conserves momentum. Now one charge is moved. It moves into in the established field of the first electron and immediately fields the force. No time delay is had. The first electron, however, does not sense that the second has moved until the disturbance in the field reaches it at light speed. It appears for the moment that momentum is not conserved. What happens is the movement of the charges induces a local magnetic field. The force imparted by the induced magnetic field is just the right strength to keep the momentum of the system balanced. Nature goes through great lengths to conserve momentum. I hope this answers your question. Frank Z
Re: Storms question about the induced field
Frank, your emphasis is on conservation of momentum, which is important but not sufficient. You also introduce the mechanism of sensing the existence of a fixed field, which is irrelevant. I ask how a structure can form when the time needed for one part to sense the characteristics of another part takes millions of years to be communicated? How does a star at one side of a galaxy know that its gravity and momentum are being exactly balanced by a star on the other side when this information takes a million years to pass between the two stars. The existence of an unstructured cluster of stars is not hard to explain. However, formation of a spiral galaxy is impossible unless the stars can communicate rapidly compared to their relative transitional speed. This requires either gravity or some other force to be communicated much faster than is normal EM radiation. I might add for your comment, that if this is true, all arguments about time based on the speed of light have no reality. Ed [EMAIL PROTECTED] wrote: The induced field is not superluminal. Take the electric force for example. The force between two charges is equal and opposite. The system conserves momentum. Now one charge is moved. It moves into in the established field of the first electron and immediately fields the force. No time delay is had. The first electron, however, does not sense that the second has moved until the disturbance in the field reaches it at light speed. It appears for the moment that momentum is not conserved. What happens is the movement of the charges induces a local magnetic field. The force imparted by the induced magnetic field is just the right strength to keep the momentum of the system balanced. Nature goes through great lengths to conserve momentum. I hope this answers your question. Frank Z
Re: Storms question about the induced field
In a message dated 7/24/2004 1:20:49 PM Eastern Standard Time, [EMAIL PROTECTED] writes: This requires either gravity or some other force to be communicated much faster than is normal EM radiation. No communication is possible at speeds faster than light speed. I ask how a structure can form when the time needed for one part to sense the characteristics of another part takes millions of years to be communicated? It does not matter if the delay is one pico second in an electronic circuit or millions of years in the universe. The mechansims the hold mometum constant are the same. All fields the communite at luminal velocities. The movement through the static field of a remote body produces an induced field. The movement of a local body produces an induced field. These induced fields are local. The produce a force which balaances the momentum of the system during the interval when the orginal field cannot. They also act as a resovour of momentum and energy. this resovour is depleated after the disturbance propagates between the two interactiong bodies. Frank frank Z
