The Incorrect View of the Speed of Light
Even though many popular science fiction stories depict objects moving at or above the speed of light, according the laws of physics, nothing with mass can move at or in excess of 3.0×107 me-ters per second.
However, there are many uses for its fitness, and lights’ properties in the present day. To gain an understanding of why this is impossible, one must understand the basics of light’s mechanics, and how it moves through space and time. In order to understand why matter cannot move as fast as light, the basics of optics, or the study of light, must be understood. What is light? Visible light is what the human eye can “see”. It is electromagnetic radiation with wavelengths from 400 nanometers, and 700 nanometers.
It is lo-cated between the Infrared (longer wave lengths), and Ultraviolet (shorter wavelengths) rays on the electromagnetic spectrum. In most physics, the word light is used to describe any electro-magnetic radiation on the electromagnetic spectrum, which is (in order of distance of wave-length), Radio waves, Microwaves, Infrared waves, “Visible” light, ultraviolet waves, X-rays, and Gamma waves. Electromagnetic waves are measured in a wave, with wavelength, ampli-tude, frequency and period. They are detected and measured by probes made out of materials that have a high conductivity, such as metal. These probes are commonly called antennas.
Broad measurements may be taken by a broadband probe, a device with three independent detectors. Frequency selective measurements are a system of measurements where only a single frequency is monitored, utilizing a field antenna, and a selective receiver. Visible light is measured in Lu-minous flux (?), Luminous Intensity (I) and Illuminance. Lumen is the total quantity of light energy given off by a source. It is usually used to rate the output of a lamp. Candela quantifies the intensity of light in a certain direction.
They are used to rate the output of luminaries. A foot-candle is number of lumens striking a surface divided by its area. Light and other electromagnet-ic radiation moves as if it were a wave. They move in a constant, distinct pattern through a vac-uum, and change in other mediums. However, it is theorized that light has a minute amount of mass, contained in photons. These tiny particles move in an oscillating wave, thus, needing no medium.
This is exemplified by a bullet traveling through the air. The bullet is in the air, but it does not require the air to transfer its energy. All electromagnetic radiation moves at an exact speed of 299,792,458 meters per second, denoted by the constant variable c. Galileo started to test the speed of light in 1638, but did have a conclusive result. In 1676 Romer studied Jupiter’s moon Io, and calculated the speed of light to be 220,000 km/s, about 26% less than its actual value.
The exact length of a meter is derived from this constant, as is the standard for time. This speed is less through other transparent mediums, such as glass. Opaque materials either absorb, or reflect light. Reflection is when a ray of light encounters another medium than which it was traveling through, and then rebounds at the same angle that it impacted the new medium, back into its previous medium. Imagine a small rubber ball thrown at a wall, and it ricocheting back.
Another way to try and understand the speed of light is to imagine the reference frame of a pho- ton (light Particle). To a photon, time is meaningless, and everything happens instantaneously, due to time dilation. At light speed, time completely stops. (Zidbits) Many films or stories depict a universe connected by faster than light travel. With events taking place on such a large scale, a fast medium of transportation was needed.
However, this is not physically possible. Due to certain properties of matter, Physicists are quite certain that light is the universal speed limit. This can be understood from Newton’s second law, F=ma (force equals mass times acceleration). This would mean infinite momentum, would equal infinite speed, however, this is incorrect. Newton created a new definition of momentum p= mv/(1-(v2/c2 ))1/2 , where p is equal to momentum, v is the speed of an object and c is the speed of light.
This means a v approaches c, the denominator moves closer to zero, although never quite reaching it. This produces a momentum that nears infinity. On the flip side, and object that is traveling the speed of light would need and infinite amount of momentum, and infinite impulse, which is clearly impossible. Another proof is explained by particles pushed close to the speed of light. As a particle is pushed close to the speed of light, it acts as if its mass were increasing, because its inertia is increasing beyond its speed.
(Inertia is f=ma). In the p= mv/(1-(v2/c2 ))1/2 equation, m is the objects rest mass. Rest mass is an objects mass with no other forces acting upon it; it is a true constant, being the same value no matter how fast the object is moving. Subatomic particles of-ten are pushed near the speed of light. These particles have a tremendous amount of momentum, and the more momentum they have, the more true their trajectory, even when they are pulled on by another force. Due to the mv equation, a particle moving at 99.
9% the speed of light will has a much larger momentum than a particle moving at 99% of the speed of light. When passing a magnet, their momentum is illustrator, as the 99% particle move off course mush more than the 99.9% particle. If these particals were moving at the speed of light, they would have infinite momentum, and would not be affected by the magnetic field, similar to light. These types of ex-periments are preformed often by scientists every day at particle accelerators, every experiment future supporting that mass cannot reach the speed of light.
Another, more recent and much more complicated explanation is one using the Higgs Field. Every particle ever, moves through and interacts with the Higgs field. That much is the same with all of the particles. However, each particle interacts with the field with different strengths. This is what gives matter its mass. Pho-tons (light particles) are an exception.
They move through the Higgs field but do not interact with it. This means that they are essential massless, and can travel at the speed of light because of the f=mv relationship, they have unlimited momentum. Though matter cannot move at the speed of light, there are many applications of light due to its near instantaneous speed. In the production of super computers, the speed at which information can be relayed through different components of the computer. These speeds are slower than the speed of light, currently at about 30 hertz. In the future, the speed has a maximum limit of the speed of light, and that will be nearly impossible to reach, due to the electromagnetic wave being slowed through a medium other than a vacuum.
Light can also be used in communication on earth, via a fiber optic wire. The fastest speed any information on earth can travel is 67 millisec-onds, due to the speed of light, and the diameter of the earth. However, the actual time it could travel through fiber optics is about 30 percent slower, due to the medium being glass. Also, in-formation is relayed using light from earth based communications to space based, such as satel-lites, probes and the ISS. For example, the time delay between communications with Apollo 8 was about three seconds. Distance is also now commonly measured with light.
Radar systems use the timing of radio waves to detect objects, as does GPS. Recently, stock trading has switched to near light speed, some traders now use microwaves rather than fiber optics, granting them a 35 percent speed advantage. The SI Meter is also defined using the speed of light, as the meter is now defined as “The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.” (BIPM) This comparison allows the scientific community to be extremely accurate in their measurements. Perhaps the most illustrated use of the speed of light is, of course, is near instantaneous travel. Although matter cannot reach the speed of light, sometime in the future, space travel may reach speeds closer to the speed of light.
In this case, time would slow down for the traveler, due to time dilation. As objects move faster, the time they experience is actually slower form an outside frame of reference. From the travel-er’s point of view, time would continue on as normal. An example of time dilation is the Twin trip theory. If there are two identical twins, and one travels at 50% of the speed of light for one year, than 1.
15 years will have elapsed for the twin whom is moving at “normal” speeds. With Travelers moving at these speeds, long distant spaceflight is much more viable, as travelers will not age as much mid-trip. To conclude, nothing with mass can move at or in excess of 3.0×107 meters per second. There are many mathematical and theoretical explanations, such as the Higgs Field, and Newton’s law.
However, there are many uses of the understanding of, and the finiteness of light, and light speed and a universal constant. Thus, the many popular science fiction stories depict objects moving at or above the speed of light are extremely misleading.