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Light, as in, physical light, is a magnificent thing. Without it, none of us could exist!

But light isn't just what gets you up in the morning, it's something fundamentally complex, something that our understanding of has been given to us by Science! 

Light, is powerful, it has the ability to create life by sparking chemical reactions. It can form a planet, or it can destroy it.

Light exists because of Einsteins most famous formula, E= MC2, where the Energy of a substance is proportionate to it's mass times the speed of light squared. That means that within a single atom, you have enough energy to produce an atomic bomb, the explosion of which is released as light!

An awful lot of light exists within every single cell, every single particle of your body!

Science has given us an awfully empowering thing, just to see that we truly are, energy based beings, for without energy, we wouldn't even have physical bodies!

But light isn't just the rainbow we see! The human eye is not advanced enough to detect all lightwaves. We see just a fraction of the spectrum. Ultra violet, infrared and beyond exist at the ends of the spectrum we see. These other lightwaves, whilst not visible to us, have very different properties to the visible spectrum. Some can pass through walls, allowing your radio or television to receive information from space! All of this light dancing around, that we can't see, and yet, it's there!

But invisible light can be picked up by cameras, a television remote glows brightly when you press a button, if you look at it through a camera or computer webcam!

Sometimes, light is not just empowering and life-giving, but can also be the most powerful crusader. 

Light, as explained by E=MC2, is energy, and therefore has to carry a bit of mass. This mass is incalculably small, but it DOES mean, that it can be effected by physical conditions. Glass and water can cause drag, electromagnetic fields and gravity can bend it, it's the universes fastest travelling putty!

But along wit hit, comes a great burden. One of the most dangerous types of light, emanates from a black hole. As a black hole consumes a star, it can become over-fed, too much is entering the black hole for it to condense at once, and so it 'belches' some into space. These are powerful radiation surges, some of which we cannot even detect. Cosmic blades cutting through space at the speed of light, destroying everything in their path. What a remarkable power, and we can't even see them with our bare eyes! They could wipe our solar system to dust in less then a second, and leave next to no visible evidence they exist!

Light, as well as existing in invisible forms, can sometimes be dangerous when it isn't present. Black holes are so dense, that they can suck light in with their gravitational wells, and this means that any light travelling to them, cannot bounce back for us to see. Instead of bouncing back, it goes there and gets consumed. We simply cannot see a black hole, even a camera would be torn to shreds before it got close enough to give any sensible information! In this way, light has been beaten, and it has left us 'in the dark' on a pressing region of our universe, that we simply cannot understand in full!

The last thing I wish to say about light, is it's ancient story. Light, from the beginning of the big bang, has been travelling all over our universe. Bouncing back and forth, these giant beams are billions of years old. When you see the light of a star that is 140 million light-years away, it has taken that light 140 million years to get here! That light is telling you the story of what that star was like all that time ago. That star might not even exist now, but the light has taken a long time to get here, so it's an old story! In the same way, as we peer into the nights sky. All of this light, comes together collectively from the ancient galaxies, and they piece together for us, the story, of the universe. A light show of pure splendor!

Thank you for reading.

Our entire universe might exist inside a massive black hole, say physicists.
Are we living inside a black hole? A few scientists think it's the best theory to explain pre-Big Bang reality.
By
Bryan Nelson
Wed, Feb 19, 2014 at 4:36 PM

Image: Wiki Commons

Our universe began with a Big Bang some 13-15 billion years ago. On this, most physicists agree. But few theorists have ventured to explain what happened "before" the Big Bang, or how the Big Bang came to be. This is because the laws of physics break down at the point of a singularity, such as with the one that physicists claim composed pre-Big Bang reality.

But a few pioneering physicists are now positing a mind-blowing new theory that could forever change our perspective on the beginnings of the universe. Perhaps, they suggest, the entire universe — all the galaxies, stars, planets, everything — exists wholly inside a massive black hole, reports National Geographic.

This radical theory would imply that our universe is just one of many. It would suggest that our universe is ultimately contained within a much larger universe — a mother universe, if you will — which harbors the black hole we're currently living in. It's a wild theory, but it's one that is slowly but surely garnering consideration from physicists.

One such physicist is Dr. Nikodem Poplawski of the University of New Haven in Connecticut. He argues that singularities, like the ones that exist at the centers of black holes, have a physical limit, a point where they can be crunched no further. Such a point would have to be massive, perhaps the weight of a billion suns or more. But once that limit is reached, the immense compacting processes at the heart of all singularities must halt.

Then, like a tightly compressed can of springs, there's a bang; a very big bang. Perhaps the Big Bang.

According to Poplawski, the reason for such a limit (and, consequently, the universe-creating explosion that follows) is that black holes spin. They spin at near-light speeds. This, in turn, creates a huge amount of torsion. Thus, such massive black holes are not just incredibly tiny and immensely heavy, they are also twisted and compressed. The multitude of forces at work are so intense that a bursting point is eventually reached. This, Poplawski proposes, is how the Big Bang happened, though he prefers to call it "the big bounce."

Such a view, if true, would revolutionize how scientists think of black holes. Rather than being dark, foreboding chasms where the laws of physics break down, black holes could instead become conduits, "one-way doors," or passageways between universes.

As of now, Poplawski's theory remains unprovable — though it can't be ruled out either. At the very least, it's fun to think about. And it's a reminder of just how wide-open our current understanding of cosmology is.

Related on MNN:
• Black holes are 'portals to other universes,' according to new quantum results
• Scientists discover 'black holes' in Earth's oceans
• 10 incredible images of black holes

http://www.mnn.com/earth-matters/space/stories/our-entire-universe-might-exist-inside-a-massive-black-hole-say

Einstein proved right over universe

Professor Albert Einstein's theory of how the universe is expanding has been proved right by scientists
Albert Einstein has been proved correct in his view of how the universe is expanding, according to a new scientific study.

The new test of Einstein's view of the universe has proved him right with "incredible accuracy" and is helping scientists to understand the mysterious acceleration of the universe.

A team of cosmologists have announced at the National Astronomy Meeting being held at the University of Manchester, the most accurate measurement ever made from when the expansion of the universe began to accelerate.

It means that the phenomenon can be explained using just Einstein's general theory of relativity and the cosmological constant - the simplest theoretical explanation for the acceleration of the universe.

The results will be used to understand what is causing the acceleration and why, and will shed new light on dark energy - the name adopted for the fundamental agent driving the acceleration about which little is known.

The cosmologists from the University of Portsmouth and the Max Planck Institute for Extraterrestrial Physics have examined the period between five and six billion years ago when the universe was almost half its present age and made measurements of extraordinary accuracy - within 1.7%.

The findings support Einstein's general theory of relativity which predicts how fast galaxies, separated by large distances, should be moving toward one another and at what rate the structure of the universe should be growing. The conclusions are consistent with the concordance model of a universe that bloomed from the big bang 13.7 million years ago.

Team member Dr Rita Tojeiro said: "The results are the best measurement of an intergalactic distance ever made, which means cosmologists are closer than ever to understanding why the universe's expansion is accelerating.

"One of the great things about Einstein's general theory of relativity is that it is testable. Our results support the theory and are fully consistent with the notion that constant vacuum energy - empty space creating a repulsive force - is driving the acceleration of the universe. These are profound statements that describe the physics of our universe at the most fundamental level.

"Critically, the results find no evidence that dark energy is simply an illusion stemming from our poor understanding of the laws of gravity - Einstein's theory has passed its most stringent test yet at extra-galactic scales."