The mystery of what happens when we go from a superposition to a definite state is known as the Measurement Problem, and it’s arguably the most mysterious outstanding problem in physics. The different interpretations of quantum mechanics...

The Stern-Gerlach Experiment in lauded in textbooks around the world for its contributions to the world of quantum physics. But for a few years, scientists unknowingly praised it for proving the wrong thing! Because instead of proving...

Pin-pricks in the celestial sphere, through which shines the light of heaven? Or gods and heroes looking down from their constellations? Or lights kindled above middle earth by Varda Elbereth and brightened with the dew of the trees of...

Since the very beginning of quantum mechanics, a debate has raged about how to interpret its bizarre predictions. And at the heart and origin of that debate is the quantum jump or quantum leap - the seemingly miraculous and instantaneous...

Neils Bohr said, “It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we can say about Nature.” Well it turns out that if we pay attention to this subtle difference, some of the most...

The search for a single number: the hubble constant, which is the rate of expansion of our universe, has consumed astronomers for generations. Finally, two powerful and independent methods have refined its measurement to unprecedented...

Invisible to the naked eye, our night sky is scattered with the 100s of billions of galaxies the fill the known universe. Like the stars, these galaxies form constellations – hidden patterns that echo the reverberations of matter and...

The holy grail of physics is to connect our understanding of the tiny scales of atoms and subatomic particles with that of the vast scales of planets, galaxies, and the entire universe. To connect quantum physics with Einstein’s general...

Now that we have a primer on the aspects of the Big Bang Theory that we know definitely happened, let’s look further into what we don’t yet know, and how the theory could progress in the future. Since there is a discrepancy between...

The foundations of quantum theory rests on its symmetries. For example, it should be impossible to distinguish our universe from one that is that is the perfect mirror opposite in charge, handedness, and the direction of time. But one by...

Challenge question: if 1kg of apples is $5 and 2kg is $10, how much is -1kg of apples? The answer? Priceless. Because you could use negative-mass apples to build warp drives, travel in time, and construct a perpetual motion machine. In...

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What happens if you cut a bar magnetic in half? We get two magnets, each with their own North and South poles. But what happens if you keep on cutting, into fourths and eighths and sixteenths and so on? Will we ever get to a single pole?...

Some see string theory as the one great hope for a theory of everything - that it will unite quantum mechanics and gravity and so unify all of physics into one glorious theory.

Between them, general relativity and quantum mechanics seem to describe all of observable reality.

In this video Paul Andersen explains how humans use information technology and instrumentation to better understand their surrounds. Technologies (including X-rays, computers, and phones) use electromagnetic waves to improve the lives...

Biologist Richard Dawkins makes a case for "thinking the improbable" by looking at how the human frame of reference limits our understanding of the universe.

The Heisenberg Uncertainty Principle might not mean what you think it means: Hank clears things up for us in this edition of IDTIMWYTIM, by distinguishing between the Uncertainty Principle and the Observer Effect, which are often conflated.

In this video Paul Andersen describes some of the properties of electromagnetic radiation. The electromagnetic spectrum varies by wavelength from radio waves to gamma rays. We only see a portion of the spectrum known as visible light. ...

The Origin of Quantum Mechanics (feat. Neil Turok)

Physicist Lee Smolin talks about how the scientific community works: as he puts it, "we fight and argue as hard as we can," but everyone accepts that the next generation of scientists will decide who's right. And, he says, that's how...

What do we think the universe is quantum? What if the universe was not quantized?

Classical mechanics was doing just fine after Isaac Newton reduced nearly all mechanical phenomena to a single powerful equation:...

In a classical universe, if we knew all the positions and velocities for all particles, we could predict the future and the past. Quantum mechanics is not like this. It shows that reality is not deterministic but is...

Parallel universes are not a theory, but deductions from the "Many Worlds" interpretation of quantum mechanics. And there is at least on other theory that predicts not alternate universes but parallel universes where the...