scalar field

Getting lost in a hall of mirrors is easy: every wall reflects another, and you feel like you've been here before. The brain gets similarly confused when surrounded by many similar places. Neurons responsible for the spatial map can fire the same signal for two different corners of a room. This is called spatial ambiguity.

The early universe resembled an overheated cauldron, seething with quantum fluctuations (random bursts of energy). In this chaos, like steam over boiling water, a special field, the scalar field, condensed. It became the 'engine' that made space expand at an incredible rate. This process is called inflation.

Water droplets shoot out of a nozzle one after another, like cyclists on a narrow track. The faster ones catch up with the slower ones and merge into larger drops. This simple mechanism is called ballistic aggregation, and until now it had only been observed on cosmic scales: this is how dust particles stick together to form planets.

In mathematics there is a sieve that sifts not dust, but infinity itself. It’s called a Q-space: here any subset turns out to be a Gδ set — a countable intersection of open sets, as if sifted through an unimaginably fine mesh.

Imagine a philharmonic orchestra playing, but the microphone picks up only a blended roar — a tutti where double basses, flutes, and timpani all merge. Physicists have grappled with a similar task for decades, staring at fields of density, temperature, or magnetic induction.

Spacetime is often pictured as a smooth fabric. But at the very microscopic level, this fabric might not be continuous; instead, it could consist of individual 'atoms'—events linked by causality. This picture of the world is called causal set theory.

The universe is expanding, and its history features two puzzling episodes that don't fit into a simple picture. The first is a brief period in its youth when everything flew apart faster than expected, as if someone had floored the gas pedal. The second is today's acceleration, as if the same pedal were pressed again, but more gently.

Physicists have mastered an elegant mathematical trick that lets them translate gravitational equations into the language of electricity. This method — double copy — works like a kind of dictionary: it replaces the complex geometry of curved spacetime, described by high-dimensional tensor fields, with the simpler rules of…

Right after the Big Bang, space swelled at an unimaginable speed — that's inflation. Now expansion has slowed, but galaxies are moving apart faster and faster. The culprit behind the acceleration has been named dark energy.

In the 1920s, Edwin Hubble noticed galaxies were moving apart — thus discovering the expansion of the Universe.

An invisible film, a quantum field, is stretched over a rubber bagel. While the bagel is small, the film stays taut and doesn't sag anywhere: the vacuum remains empty. But once you stretch the bagel to a certain size, a dent spontaneously appears in the film — the field starts to be felt at every point. This dent is not random.

An attempt to suppress room background noise by adding anti-sound turns into speaker howl if the circuit has an error. A similar glitch occurred with a theory that set out to remove the main cosmic hum — the inexplicably weak dark energy.

A stone on a table won't budge without a kick. Where does this stubbornness come from? The idea that the rest of the Universe is to blame was put forward over a century ago. Now it has been formalized into a rigorous theory. In the new work, gravity is described not as an attraction between bodies but as a field that sets the scale of distances and time.

The universe is expanding faster and faster, and the standard explanation is a positive cosmological constant, that is, a de Sitter vacuum. String theory, which aspires to be the theory of quantum gravity, should be able to describe such a vacuum, but after decades of effort, no reliable construction has emerged.