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Travel Faster Than Light


Can something travel faster than light?

from online, stanford.edu:

Einstein's Spacetime
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Physics at the end of the nineteenth century found itself in crisis: there were perfectly good theories of mechanics (Newton) and electromagnetism (Maxwell), but they did not seem to agree. Light was known to be an electromagnetic phenomenon, but it did not obey the same laws of mechanics as matter. Experiments by Albert A. Michelson (1852-1931) and others in the 1880s showed that it always traveled with the same velocity, regardless of the speed of its source. Older physicists struggled with this contradiction in various ways. In 1892 George F. FitzGerald (1851-1901) and Hendrik A. Lorentz (1853-1928) independently found that they could reconcile theory and experiment if they postulated that the detector apparatus was changing its size and shape in a characteristic way that depended on its state of motion. In 1898, J. Henri Poincaré (1854-1912) suggested that intervals of time, as well as length, might be observer-dependent, and he even speculated (in 1904) that the speed of light might be an "unsurpassable limit".

None of these eminent physicists, however, put the whole story together. That was left to the young Albert Einstein (1879-1955), who already began approaching the problem in a new way at the age of sixteen (1895-6) when he wondered what it would be like to travel along with a light ray. By 1905 he had shown that FitzGerald and Lorentz's results followed from one simple but radical assumption: the laws of physics and the speed of light must be the same for all uniformly moving observers, regardless of their state of relative motion. For this to be true, space and time can no longer be independent. Rather, they are "converted" into each other in such a way as to keep the speed of light constant for all observers. (This is why moving objects appear to shrink, as suspected by FitzGerald and Lorentz, and why moving observers may measure time differently, as speculated by Poincaré.) Space and time are relative (i.e., they depend on the motion of the observer who measures them) — and light is more fundamental than either. This is the basis of Einstein's theory of special relativity ("special" refers to the restriction to uniform motion).
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I see this theory as arising from a confusion between a velocity of mass or of light.

from online:
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EM radiation is created when an atomic particle, such as an electron, is accelerated by an electric field, causing it to move. The movement produces oscillating electric and magnetic fields, which travel at right angles to each other These perpendicular electric and magnetic fields propagate at the fastest speed possible in the universe: 186,282 miles per second (299,792,458 meters per second) in a vacuum, also known as the speed of light. The synchronized fields have certain characteristics, given as frequency, wavelength or energy.
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Light is made up of electromagnetic fields and no mass so it is not subject to thermodynamics where the energy or heat present in mass must be conserved.

The velocity of light is fixed by the propagation of the EM fields in space, and is not subject to acceleration of a mass or its momentum. The speed of these fields drops when passing through matter, so then light moves at less than c. Given atoms have positive nuclei some interference with the EM fields could be expected.

Einstein's theory of relativity is based on considering what if a person (who has mass) moved at the speed of light which was assumed to be a limit.
 However light is the propagation of EM fields and has no mass.
They are inherently different.

continuing from the reference:
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Four-dimensional Minkowski spacetime is often pictured in the form of a two-dimensional lightcone diagram, with the horizontal axes representing "space" (x) and the vertical axis "time" (ct). The walls of the cone are defined by the evolution of a flash of light passing from the past (lower cone) to the future (upper cone) through the present (origin). All of physical reality is contained within this cone; the region outside ("elsewhere") is inaccessible because one would have to travel faster than light to reach it. The trajectories of all real objects lie along "worldlines" inside the cone (like the one shown here in red). The apparently static nature of this picture, in which history does not seem to "happen" but is rather "already there", has given writers and philosophers a new way to think about old issues involving determinism and free will.

The language of spacetime (known technically as tensor mathematics) proved to be essential in deriving his theory of general relativity.
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There is a related topic: Mass in special relativity:

Relativity proposes the concept of a relativistic mass, to deal with motion near c, with a very high momentum.

from wikipedia:

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 it turns out to be impossible to find a general definition for a system's total mass (or energy). The main reason for this is that "gravitational field energy" is not a part of the energy–momentum tensor; instead, what might be identified as the contribution of the gravitational field to a total energy is part of the Einstein tensor on the other side of Einstein's equation (and, as such, a consequence of these equations' non-linearity). While in certain situations it is possible to rewrite the equations so that part of the "gravitational energy" now stands alongside the other source terms in the form of the stress–energy–momentum pseudotensor, this separation is not true for all observers, and there is no general definition for obtaining it.
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I might be wrong but it appears the theory of relativity is based on trying to understand how matter, in 'uniform motion' can move at the speed of light which was perceived as a limit. Minkowski space time also dealt with the speed limit of light.

from wikipedia:

 the term cosmic ray almost exclusively refers to massive particles – those that have rest mass – as opposed to photons, which have no rest mass, and neutrinos, which have negligible rest mass. Massive particles have additional, kinetic, mass-energy when they are moving, due to relativistic effects. Through this process, some particles acquire tremendously high mass-energies. At the higher end of the energy spectrum, relativistic kinetic energy is the main source of the mass-energy of cosmic rays.
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I interpret this to mean cosmic ray particles have extremely high kinetic energies but their velocity is not defined. The word 'relativistic ' could mean near c or greater. Are some > c?

I found this for LHC:
For the design energy of 7 TeV, that would be 99.9999991% the speed of light.

If the LHC uses EM fields to control this motion then I suspect the particles cannot go faster than those fields can 'move' which is c.

from online:
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 Parker Solar Probe became the fastest spacecraft relative to the sun, exceeding a heliocentric velocity of 153,454 mph (42.6 miles per second; 68.6 kilometers per second).
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This is far from c.

As a simple observation:
a)  light is a unique phenomenon with its EM fields.
b) light involves no mass,
c) The motion of matter is driven by Newtonian physics subject to thermodynamics (conservation of energy).

d) Relativity assumes c is the universal speed limit for mass. Has that limit been proven? I can find nothing online.

e) Given enough force to drive sufficient acceleration, travel faster than the speed of light could be possible theoretically.

f) Many years ago the speed of sound was considered a limit. It was not.

Does mass have a velocity limit?

Date updated 03/22/2019

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