When we think of Kelvin temperature, we think only in positives, since zero Kelvin is also absolute zero, the point at which a particle has absolutely no energy, and thus no movement or vibration. Scientists in Germany, however, managed to create the hottest temperatures ever recorded by creating a substance with a negative Kelvin temperature.
How is this possible? Well, in order to understand this bizarre concept, we have to go back to our definition of temperature. In thermodynamics, we t
When quantum physics deals with the smallest of small particles, and computer science deals with elaborate algorithms and problem solving, you might wonder why these two sciences would ever cross paths, but research since the 1980s has spawned a new science from these two already elaborate fields: quantum computing.
In quantum computing, rather than using ones and zeros to represent data, the unique quantum state of electrons is used to encode information. This principle is particularly usef
Seeing and hearing are two senses that operate similarly, in that both require waves as sensory input. With sight, light waves enter our eyes, which bend the light toward the retina, which in turn convert the light into electrical impulses that carry information to our brain. With hearing, sound waves cause vibrations in the hairs of our cochlea, an inner part the ear, and the vibrations translate into electrical impulses that go to the brain.
Knowing this, scientists have sought for years
Lasers are everywhere. We use them in medicine, telecommunications, manufacturing, and even in our personal computers (to burn a CD, for example). How exactly do they work, though? Typically whenever we turn on a light of some sort, the photons it emits propagate in all directions, yet with a laser, all the photons flow in a neat, straight, steady stream (making them ideal pointers). How does that happen?
Many people do not realize it, probably because the term has become so commonplace,
Have you ever wondered how spacecraft like the Hubble Telescope or the Kepler can see so remarkably far into space? The physics behind it lies in how light bends around planets and stars as it propagates through space. Einstein showed that massive objects bend the four-dimensional spacetime continuum (with the fourth dimension being time). As a result, light passing by massive objects, like planets, stars, and black holes, bend around the objects as they pass by.
The bending of light can m
For years, scientists have tried to make fusion a viable source of renewable energy for the world. In the sun, hydrogen molecules are smashed together to form helium nuclei and tremendous energy that allows the sun to give off its brilliant light. Scientists have tried to recreate this fusion reaction on a smaller scale so that they can produce tremendous amounts of energy and essentially solve our world's energy problem.
In order for an energy source to be viable, the reaction involved must
A few years ago, I remember watching a CSI: NY episode where thieves were stealing expensive jewelry from different jewelry stores, and a peculiar problem left the investigators stumped for a part of the episode. The problem had to do with the shattered glass from the glass displays. If a person strikes a glass object, like the casing in the stores or a window, the inside of the glass, which can be seen from a side view of a shard, will leave telltale marks indicating the direction from which
One subject that has received a lot of attention, speculation, and research in the last twenty or more years is the elusive Dark Matter. It gets its peculiar name from the fact that dark matter does not look or behave like normal matter. In fact, we don't even know if it really exists! However, recent experiments, both here on Earth and up in outer space, seem to give clues as to the nature of dark matter.
So where did the idea of dark matter come from? It came from a discrepancy in the mass
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