Breakthough study finds remnants of Big Bang

Inflation Big Bang Expansion Image Diagram NASA Science Universe Weekly Show

The universe is a big place. Most physicists say it is infinite, and estimates of our observable universe fall around 93 billion lightyears across. Fortunately, math and science give us the tools to unravel what we cannot see, such as last week’s breakthrough discovery of the “echo” from the Big Bang.

The Big Bang theory posits the universe burst from a single point some 13.7 billion years ago. In a fraction of a second it underwent staggering expansion, growing exponentially at speeds faster than light. Early phases of the universe contained plasma so “dense” (high-energy) that photons could not escape. About 380,000 years later, the plasma cooled enough to let light push through, giving the universe its first moment of transparency. This theory is widely accepted by the scientific community and explains many properties of our universe, such as cosmic background radiation, large-scale structures, and the large presence of light elements (more on these in future posts).

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Stephen Hawking: there are no black holes

Black Hole Artist's Impression Astronaut Falling Into Tidal Forces Firewall Hawking Weekly Show Stephen

Famed physicist Stephen Hawking announced last week there are no black holes—at least not the way we think of them. His new, not-yet-peer-reviewed paper says the idea of an event horizon—the point of no escape—violates quantum mechanics and therefore does not exist. In doing away with the event horizon, Hawking claims to have solved the firewall paradox, one of the most pressing problems in modern physics.

First, some background. Stephen Hawking is a theoretical physicist and cosmologist and the Director of Research at the Centre for Theoretical Cosmology at Cambridge University. His work in quantum mechanics and general relativity is a cornerstone of modern physics and has made him one of the most famous scientists of the past century.

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The scale of the universe

Of all the secrets and mysteries of science, I find myself most fascinated by the universe. It’s birth and evolution,  its future and unexplored depths–these stories keep me coming back for more. Perhaps the most exciting part is that there is so much we do not know. We sit on our lonely planet, pondering how everything came to be and where it is going. If one phrase can describe the history of cosmology, it is the proverbial “the more we learn the less we know.”

Rosette Nebula Nursery Picture Star Formation Colors Scale of Universe Weekly Show

The Rosette nebula, a stellar nursery approximately 5,000 light years away. How can we possibly understand scales that leave everything we know incomprehensibly large or small?

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Why classical physics says the sun doesn’t shine

In the first half of the twentieth century, physicists discovered something alarming about the sky. When they looked up, they saw the sun—and it was shining. You see, according to their calculations this was impossible. Their models stated that the sun was not enough energy to shine. Despite their efforts to explain the problem, the numbers were loud, clear, and anything but bright.

First, some background on the sun. Like all stars, the sun converts its mass into energy via nuclear fusion. In short, the gravity of its outer shells heats the core until it can convert hydrogen into helium, producing enough energy to support itself. This process gives off immense radiation, which we perceive as heat and light. I explained how stars work a few weeks ago—click here to learn more.

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Four crazy mysteries of science

Are there unsolved questions in science? What are the limitations of our theories? Progress brings new questions, implications that challenge our understanding of the universe and ourselves. Below are four crazy mysteries of modern science. Feel free to leave discoveries that peak your interests in the comments section below.

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This. Is So. Cool

Absolute hot

How hot can it get? Scientists have pondered this question for centuries. Classical physics defines temperature as a measure of energy. Through the late 19th century, most scholars thought that if you could continuously add energy to a system it would become infinitely hot. According to quantum mechanics, however, this might not be the case.

All objects emit light. The hotter the object, the shorter the wavelength and more energetic the light. One of the principles of quantum mechanics is that there is a Plank length, a shortest possible distance between things in the universe. What would happen, then, if an object became so hot that its light’s wavelength reached the Planck length? Could the object become any hotter? Current theories break down at this point. To put it simply, nobody knows.

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