What is light?........?

Question

I watching a show about black holes the other day, it said that nothing can escape a black hole not even light. Well what is light, how would you describe it.
Also
I would like to know different theories on how the universe formed or whatever you want call this thing we are floating around in.
Anythings possible or does everything happen for a reason?
All answers welcome even if your a little bit crazy :)

Answer 1

Are you trying to hurt my brain today?

Light is a type of electromagnetic energy or radiation. Light is in a constant state of fluctuating electrical and magnetic energy. The electrical field will be at maximum when the magnetic field is at minimum. The electrical field will be at minimum when the magnetic field is at maximum etc. These properties are defined in terms of wavelength, frequency, and speed of propegation. Photons are a form of energy travelling along these waves. They are not particles but they can take on some of the characteristics of a physical particle. They have no mass but they have momentum proportional to the frequency. They are electrically neutral and thus are not affected by electrical or magnetic fields.

It was Einstein who changed the understanding of how light waves seem to bend by gravity from the old Newtonian views. Today, we think not in terms of vector forces when describing the Universe but in terms of spacetime. The consequences of the 'shape' of the Universe.

Let's use an example of a body with a large mass. It does not have to be a black hole although that would be an extreme example which seems to come to most peoples mind the quickest. The mass of the object exerts a large gravitational pull not only on the objects around it but also on the space around it. Thus, it follows that the space around this object is already curved. Light travelling along this space would simply follow the curvature which is already in existence. Gravity is not bending the light. The light is simply following the curvature of spacetime which is already bent.
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There are several theories on how the Universe was formed. Just so I don't offend anyone, let's start out with Creationism. Of the other theories, the most widely accepted would be the Big Bang theory but even within this theory are theories on how the Universe evolved.

Other theories (some related to the evolution of the Big Bang):
-The inflationary theory (in many variations).
-The ether theory (the universe consists of a material through which light and everything else moves)
-Superstrings, M-theory
- Supersymmetry (standard model)
- Multiverse theory (ours is just one of many parallell universe)
- Many worlds theory (whenever a quantum decision is made, the universe splits into two, in which one possible outcome happens in each)
- The universe was crafted by intelligent (non-god) beings (see Marcus Chown's The Universe Next Door)
-Protouniverse
-Cyclic universe
-Steady State
-Oscillating
-Inflationary
-Bouncing
-Bubble
-Hawking-Turok Instanton theory



The concept that the universe began from a single point, underwent an explosion, and has been flying apart ever since, has changed since it's inception in the 1920's. Current belief is that the big bang was not an explosion at all but an expansion or stretching of space. It is not that things are flying out from a point. Rather, all things are moving away from each other. Everything would appear to be at the center of an explosion. It is an optical illusion - everybody moves away from everybody else and there is no center. The beginning was a cosmic singularity. At that time, the universe had nearly infinite density and temperature. Other models show the early universe in a very different state - cold and nearly vacuous. This is the ekpyrotic model.

Yep, anything's possible lol.

Does everything happen for a reason?
"What choice did God have in creating the universe?" - ALBERT EINSTEIN

Answer 2

What is light? Seems like a silly question at first, but after some thought most of us will agree we don't know much. It comes out of the sun, lets us see things, and makes us warm. We can't grab it, can't outrun it, and can't seem to define it. Yet, physics has made many successful attempts at clarifying what light is and what it can do.

Much of the difficulty in defining light results from its seemingly contradictory behavior. In defining the behavior of a phenomenon scientists try to create a model, a system of rules explaining what is observed. In the early part of the 20th century, there were two different models for light. One looked at light as a particle and the other looked at light as a wave. Just thinking about the two ideas seems a bit strange. How can waves, vibrations in things, and particles both describe light when they are so different? In the following pages we will try to explain light from both perspectives.

With the development of quantum mechanics in the 20th century came the decision that it's both! Light can act like a particle and a wave and the same time. We just see different aspects of its nature at different times. If this at all seems strange, don't worry. Quantum physics is confusing to most people, even to the people who invented it!

Answer 3

Electromagnetic waves. Radio waves are the same thing with light, only of different wavelengths, wich we cannot percive. We se electromagnetic waves only between certain limits.

as any wave, light also has wavelengths, so, the white light is created by combines electromagnetic waves of several different wavelengths.

That's why the rainbow forms, different wavelengths my choose different difraction trajectories.

Light can be affected by gravity , so really heavy shtuff, like the sun, can bend light,

Einstein, i belive, said that if you bend light enoughf to form a loop, you could travel in time,or something like that.

Also, another curious fact is that likgtspeed is the only constant thing in this whole crazy universe, everithing else fluctuates, even time.

But it is belived that lightspeed slowly decreases in time, because of the expansion of the universe.

That's all i know about light, although i think it's not exactly what you were searching for... I study phizics at school, and i'm only in 11th grade, soon in 12th, and although it is vrey interesting, i friggin' hate my teacher.

Answer 4

light is hard to explain. its made of protons, which are particles like atoms that have proterties like waves. it travels at 186,000 miles a second, and nothing other than light can travel at or above that speed without having an infinite amount of energy. its created in stars, also your flashlight too i guess. and for you to see light it needs to reflect off of something like an atom. thats why space seems dark. there are tons of protons there, but since there is about 5 atoms per cubic meter of space there is nothing for them to reflect off of so you can see them

and as for theories on the universe, most include the big bang. the big bang says that all of the energy was compacted into a small sphere smaller than a grain of sand. the energy for some reason exploded and it cooled enough within 1-3 seconds to form quarks, which are the building blocks of protons and neutrons, and electrons. quarks formed protons and they binded with electrons and formed hydrogen. gravity pulled hydrogen atoms together to make stars. they combine 2 hydrogen atoms to create a helium atom. once a star runs out of hydrogen it trys combines the helium into carbon and oxygen but fails unless its a bigger star. bigger stars can form elements all the way to iron.

most different theories explain how the big bang happened. the multiple universe theory says that 2 universes collided and caused a massive shockwave that set off the big bang. and the oscillation theory says that the universe is the result of a series of big bangs and 'big crunchs'. that basically says eventually gravity will pull everything back together into that same little ball.

and id like to just share this theory because i find it interesting, although its been proved false. one theory says that on the other end of a black hole is a white hole in another universe connected to the black hole by a wormhole. the whitehole spews out everything sucked in by the black hole. and according to this every universe is just the inside of a black hole, and every black hole in our universe has another universe inside of it. this theory is MATHEMATICALLY proveable, but scientifically it violates several scientific laws.

hope this helped somewhat.

Answer 5

Photons

Answer 6

Light is electromagnetic waves and photon particles that travel from there source.

Answer 7

Light is the opposite of heavy. ;))