Quantum, Relativity & Forces Explained | Pixelated Physics

19 articles

Pixel-art light wave stretching from blue to red as it travels from a spiral galaxy across expanding space, illustrating cosmological redshift

Is Cosmological Redshift a Doppler Shift? Stret...

Light from distant galaxies arrives stretched to longer, redder wavelengths. Is that a Doppler shift from galaxies racing away, or space itself stretching the light? Here is the formula that...

Is Cosmological Redshift a Doppler Shift? Stret...

Light from distant galaxies arrives stretched to longer, redder wavelengths. Is that a Doppler shift from galaxies racing away, or space itself stretching the light? Here is the formula that...

Pixel-art night sky with a cratered Moon on the left and banded Jupiter on the right flanked by four tiny moons, titled Telescope, tea, trouble

Sidereus Nuncius: What Galileo Saw in 1610

In March 1610 Galileo published a short book of telescope observations: a mountainous Moon, a Milky Way made of stars and four moons circling Jupiter. Here is what he saw,...

Sidereus Nuncius: What Galileo Saw in 1610

In March 1610 Galileo published a short book of telescope observations: a mountainous Moon, a Milky Way made of stars and four moons circling Jupiter. Here is what he saw,...

Pixel-art pulsating yellow star with cyan and violet rings beside a lime sawtooth light curve over a ruler, titled Leavitt’s law: the blink is the ruler

Henrietta Leavitt's Law: How a Blinking Star Me...

In 1912 Henrietta Leavitt showed that brighter Cepheid stars pulse more slowly. That one relation became the first rung of the cosmic distance ladder, and it still sits at the...

Henrietta Leavitt's Law: How a Blinking Star Me...

In 1912 Henrietta Leavitt showed that brighter Cepheid stars pulse more slowly. That one relation became the first rung of the cosmic distance ladder, and it still sits at the...

A blue giant star losing a stream of gas to a glowing accretion disk around an unseen black hole

How Do We Know Black Holes Exist if We Cannot S...

A black hole gives off no light of its own, so how can anyone claim to have found one? Through four independent lines of evidence: X-ray binaries like Cygnus X-1,...

How Do We Know Black Holes Exist if We Cannot S...

A black hole gives off no light of its own, so how can anyone claim to have found one? Through four independent lines of evidence: X-ray binaries like Cygnus X-1,...

The observable universe as a glowing sphere of galaxies around a central observer point

How Big Is the Observable Universe if It Is 13....

Light has only had about 13.8 billion years to reach us, so why do cosmologists put the edge of the observable universe about 46 billion light-years away? The answer is...

How Big Is the Observable Universe if It Is 13....

Light has only had about 13.8 billion years to reach us, so why do cosmologists put the edge of the observable universe about 46 billion light-years away? The answer is...

A massive star cut away into glowing onion-like fusion shells beside a supernova scattering heavy elements

How Do Stars Make Heavier Elements? The B²FH Pa...

The Big Bang left the universe almost entirely hydrogen and helium. Nearly everything else, the carbon in you and the iron in your blood, was forged in stars. In 1957...

How Do Stars Make Heavier Elements? The B²FH Pa...

The Big Bang left the universe almost entirely hydrogen and helium. Nearly everything else, the carbon in you and the iron in your blood, was forged in stars. In 1957...