Quantum, Relativity & Forces Explained | Pixelated Physics

16 articles

Pixel-art diamond-shaped Penrose diagram of glowing light-ray lines in a violet night sky, with a lone traveller on a hilltop

Penrose Diagrams Explained: All of Spacetime on...

How do you draw the whole of space and time, out to infinity, on one sheet of paper? Roger Penrose found a way: shrink distances but keep every angle, so...

Penrose Diagrams Explained: All of Spacetime on...

How do you draw the whole of space and time, out to infinity, on one sheet of paper? Roger Penrose found a way: shrink distances but keep every angle, so...

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 Earth with two airliners carrying atomic clocks on eastward and westward orbits, titled clocks around the world 1971

The Hafele–Keating Experiment: Clocks Around th...

In October 1971 two scientists bought airline seats for four atomic clocks and flew them around the world, once eastward and once westward. When the clocks came home, they no...

The Hafele–Keating Experiment: Clocks Around th...

In October 1971 two scientists bought airline seats for four atomic clocks and flew them around the world, once eastward and once westward. When the clocks came home, they no...

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 black hole shadow ringed by a bright photon ring, with its glowing accretion disk lensed around it

What Is the Photon Sphere, and What Did the Eve...

Near a black hole there is a radius where gravity bends light into a circle: the photon sphere, at r = 3GM/c² for a non-spinning hole. It is unstable, so...

What Is the Photon Sphere, and What Did the Eve...

Near a black hole there is a radius where gravity bends light into a circle: the photon sphere, at r = 3GM/c² for a non-spinning hole. It is unstable, so...