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Quantum Entanglement: Slower Than Light

In Physics by Brian Koberlein0 Comments

China recently launched a satellite to test quantum entanglement in space. It’s an interesting experiment that could lead to “hack proof” satellite communication. It’s also led to a flurry of articles claiming that quantum entanglement allows particles to communicate faster than light. Several science bloggers have noted why this is wrong, but it’s worth emphasizing again. Quantum entanglement does not allow faster than light communicationRead More

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The Nitro Project

In Chemistry by Brian Koberlein2 Comments

Our atmosphere is about 78% nitrogen and 21% oxygen, with traces of other things like water and carbon dioxide. It’s an odd mix compared to the atmospheres of other planets. Jupiter and Saturn are dominated by hydrogen and helium, The thick atmosphere of Venus is about 96% carbon dioxide, and only 3% nitrogen, which is about the same ratio as the thin atmosphere of Mars. So why is our atmosphere so dominated by nitrogen? Read More

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When You See The Flash

In Stars by Brian Koberlein0 Comments

A nova occurs when a star brightens by several magnitudes over a very short time. Like supernovae, they’ve been recorded throughout history. We now know novas are caused by a dance between two stars, where a white dwarf orbits close enough to a companion star that it captures material from its companion until it reaches a critical limit and it’s outer layer explodes. Studying the details of this phenomena is difficult, because a nova is usually too faint to be noticed until it brightens. But thanks to large sky surveys, that’s starting to change. Read More

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Here Be Dragons

In Astronomy by Brian Koberlein9 Comments

Take a mass, any mass. Compress it into an ever smaller volume. As its density rises, the gravity near its surface with increase. Squeeze it into a small enough volume and the surface gravity will become so strong that nothing can escape, not even light. Squeeze anything into a small enough volume at it will become a black hole. The defining feature of a black hole is its event horizon, which defines the volume of no return. But the event horizon also marks a region where our basic understanding of physics breaks down. It is perhaps the greatest paradox of modern astrophysics.Read More

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Too Big To Fail

In Astronomy by Brian Koberlein9 Comments

Earth is showered with cosmic rays. They are protons, electrons and atomic nuclei traveling at nearly the speed of light, and strike our atmosphere to create the most power particle collisions ever observed. As a particle approaches the speed of light, it’s energy increases exponentially, so it might seem that there is no upper limit to just how much energy cosmic rays can have. But it turns out there is a limit, at least in theory. Read More

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Dawn Of Time

In Astronomy by Brian Koberlein5 Comments

Although the Sun seems ageless and never changing, it is a star like any other. It’s only a bit older than the Earth itself, and like every star it formed from the gas and dust of a stellar nursery. As we’ve come to understand stellar evolution, it has become clear that stars get warmer as they age. Billions of years ago, our Sun was about 70% as luminous as it is today. That means young Earth received less heat from the Sun than it does today. So much less heat that it wasn’t enough to sustain liquid water. But geologic evidence clearly shows that there were oceans of water in Earth’s youth. Read More

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The Infinity Paradox

In Astronomy by Brian Koberlein13 Comments

No matter what direction you look in the night sky, it looks basically the same. In astronomy terms we say the Universe is homogeneous and isotropic. Sure there are areas where galaxies cluster together, and other areas where galaxies are rare, but on average the distribution of stars is pretty even. Because of this, an early idea for the cosmos is that it is the same everywhere forever. It seems both ageless and infinite in expanse. But if that’s the case it raises a few troubling paradoxes. Read More

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Riddle Me This

In Astronomy by Brian Koberlein6 Comments

Anyone practicing science needs to get comfortable with uncertainty. Often the questions raised lead to an answer that is simply “we don’t know.” But there are times when we are instead faced with a contradiction. One set of evidence and theoretical reasoning leads to a conclusion in contradiction with another set of evidence. Usually these contradictions resolve themselves pretty quickly, but there are times when these contradictions grow into a paradox. While some of the most famous astronomical paradoxes are now used to demonstrate where our reasoning went wrong, others still challenge us with no clear resolution. Read More