Is there an existent glossary or list of terms or dictionary itself that EUers refer to as an agreed upon authoritative work regarding the definitions of words /terms in EU or used to describe the EU Theory itself?
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Yeah I agree we are at the stage of requiring a text book. I thought we might use the <Physics Hypertextbook> and just delete and replace as necessary.
This is a response to a request for a definition of EU terminology. A suggestion was offered to begin with something like the online Physics Hypertextbook.
I expect space-time, the basis for a gravity-only universe, must be countered in EU terminology.
Euclidean geometry is an example of synthetic geometry, in that it proceeds logically from axioms describing basic properties of geometric objects such as points and lines, to propositions about those objects, all without the use of coordinates to specify those objects.
The purpose of a geometry is to specify locations of objects in a consistent manner.
from the PH book:
Displacement, velocity, and acceleration (like all vector quantities) are geometric entities. They have magnitude, which is something like length, and direction, which is just the angle they make with respect to a reference direction like "up" or "north". It is always possible to create a vector diagram or a series of diagrams from a properly worded description of a kinematic event. The challenge for those studying this topic is learning how to effectively represent motion with a static picture.
Synthetic geometry allows other entities into this framework for the observer.
From the Physics Hypertextbook:
Newtonian relativity: absolute linear motion at a constant velocity cannot be detected, nor can absolute rest. All motion is relative to a frame of reference. It is not possible to distinguish motion with a constant velocity from rest. All constant velocity frames of reference are equivalent (including frames of reference that appear to be at rest — after all, a prolonged state of rest is motion with a constant speed of zero).
A frame of reference is always defined by the observer. The geometry is defined by the observer, including the relationship of its axes to physical space. For example with the simple 3-D Euclidean geometry the point at X0,Y0,Z0 in the geometry is often at the convenient lower left corner of the working space. This relationship is defined by the observer, defining how they describe a position in physical space within this frame of reference.
An alternate geometry is the celestial coordinate system defined by two planes with a distance to the object enabling the observer to describe any position in the observable universe. Tthis geometry is restricted to being on Earth. Observers beyond Earth must perform coordinate system transformations to move the zero reference (the center of the Eath) for this geometry to their location beyond Earth.
The infinite universe has no fixed point to serve as a zero reference point for a geometry. Currently we use the Earth as the fixed point required by this geometry for our observations in the universe.
Plaques on the Pioneer 10 and 11 probes defined Earth's position in the Milky Way using 14 pulsars. Any geometry not based on Earth must reference objects moving relative to Earth and to each other.
An observer's frame of reference can never be directly related to a specific point in the universe because space in the infinite universe has no geometry.
from the PH book:
Coordinated Universal Time (abbreviated UTC) is the basis of legal time throughout the world.
I think the big thing is that everyone agrees what time (or day) it is. Not that the time is any particular number. Time is a social construct, remember.
Time dilation is a difference in the elapsed time measured by two clocks, either due to them having a velocity relative to each other, or by there being a gravitational potential difference between their locations.
Length contraction is the phenomenon that a moving object's length is measured to be shorter than its proper length, which is the length as measured in the object's own rest frame. It is also known as Lorentz contraction or Lorentz–FitzGerald contraction and is usually only noticeable at a substantial fraction of the speed of light. Length contraction is only in the direction in which the body is travelling. For standard objects, this effect is negligible at everyday speeds, and can be ignored for all regular purposes, only becoming significant as the object approaches the speed of light relative to the observer.
Both time dilation and length contraction are observations by the moving observer. Neither affects the universal time nor an object's physical length.
from the PH book:
From the point of view of a stationary observer, all events in a frame of reference moving at the speed of light take an infinite amount of time to occur. No events can transpire. Nothing can happen. Time ceases to exist.
Unfortunately for relativity, hydrogen atoms near a quasar are observed to move faster than the speed of light, as measured by their red shift. Objects are not limited by the speed of light. That was the unverified belief in the late 1800's.
Time is not a physical entity so time cannot cease to exist.
from the PH book:
Einstein developed a new view of time first and then space.
Space-time is more than just a set of values for identifying events. Space-time is a thing unto itself.
Space-time is just the geometry in the observer's reference frame, so it is just a set of values. Time is just another dimension of a useful quantity. Considering the importance of thermodynamics a 5th dimension for temperature could be useful for an observer's geometry. A geometry is used for descriptions of objects; a geometry is not a real thing.
Both time dilation and length contraction are observations by the moving observer and are not part of space-time.
Relativity proposes this space-time geometry, including time among its dimensions, can be distorted when the observer is in the gravitational field of another object.
Instead of the Newtonian force of gravity at a vector between the two bodies causing a change in the observer's motion, relativity proposes the observer's geometry is distorted so rather than moving in a straight line the observer moves in a curved path in this field.
This distortion in the geometry is limited to the observer. This is not real 'space.'
A black hole is a theoretical entity in relativity where a very large mass will cause the observer's geometry around that mass to collapse to a point. The implication is if space-time is real then all that mass is compressed into this point in the observer's geometry. A point is a geometric concept and has no physical size. The result is the mass is within a zero radius geometric concept meaning there is infinite density.This is not physically possible.
This concept is mathematical and not a real thing.
If the observer's path of motion is directly at a black hole, relativity proposes the observer will follow a distorted path in their space-time geometry and must stop at this point in their geometry.
Outside of relativity which assumes gravity cannot exceed the speed of light, gravity is known to be instantaneous so the observer's velocity is affected by the object's gravity, whose force increases as the distance decreases. The observer will physically collide with this massive object. The observer will not disappear into this geometric point.
Black holes do not exist.
Space-time will curve only by a gravitational field so that is assumed to be the only field affecting motion.
However EU recognizes electric fields and magnetic fields affect the motion of charged objects. Space-time ignores known physics: these real electromagnetic forces.
Space-time is not a real thing.
The PH book has a section for electricity and magnetism.
link to the textbook referenced above.
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