standard cosmological model

A census by body shape: that's one way to describe what astronomers did with 6348 massive galaxies. Instead of height and weight, they measured how concentrated the light is toward the center, how flattened the galaxy is, and how asymmetric its shape is. Then they ran the same measurements on galaxies from three computer models of the universe and compared the results.

The standard cosmological model ΛCDM (which includes dark energy and cold dark matter) is the score of a cosmic symphony. It describes how space expanded after the big bang. How dark matter clumped together. How galaxies ignited. For a long time, everything played flawlessly.

Eight hundred million years after the Big Bang, and at the heart of a young galaxy a monstrous engine is already throbbing. A black hole with a mass of ten billion suns devours matter so greedily that its radiation should outshine everything around it. But outside, silence.

The cosmos resembles silk fabric with threads of the dark web showing through. We only glimpse tiny swatches of the real tapestry — through telescopes, in actual galaxy catalogs. To separate the fundamental signal from astrophysical noise in the cosmic pattern, statistical analysis demands thousands of plausible sketches — synthetic sky maps.

The cosmological principle – the notion that the Universe is homogeneous and isotropic on large scales – has guarded our understanding of the world since the time of Edwin Hubble and Georges Lemaître, whose ideas formed the basis of the Big Bang model.

Through the ripples on the water, pebbles at the bottom of a pool look shifted and warped. In a similar way, the gravity of invisible dark matter bends the light of distant galaxies — a phenomenon known as weak lensing.

A magnet with only one pole — north, but no south. Split it in half, and instead of two ordinary magnets, you get two more one-pole magnets. In our world, no such particle has been found, although many theories predict their existence. These hypothetical objects are called magnetic monopoles. The authors of the study noticed a curious connection.

In the very beginning, moments after the Big Bang, the universe was ridiculously symmetric: particles and antiparticles in equal measure. But a tiny imbalance occurred, like one extra grain of sugar in a kilogram, and the entire familiar world, stars, planets, people, arose from that surplus. How nature created this imbalance remains a mystery.

Cosmology is going through strange times. On one hand, the standard model with dark matter and dark energy beautifully describes the large-scale structure. On the other, it's cracking at the seams.

Axions are hypothetical elementary particles introduced in 1977 by Roberto Peccei and Helen Quinn to resolve the so-called strong CP problem in the Standard Model of particle physics.

The universe resembles a giant sponge: bright filaments of galaxies weave around enormous dark voids. Inside these filaments and walls hide clumps of invisible dark matter — halos. When dark matter particles collide and decay, they produce ordinary particles that telescopes can catch.

You're inflating a balloon, but with each pump of the bulb, the rubber doesn't just stretch: it subtly changes its elasticity. Gravity works similarly in the new model: not as a rigid stage for the cosmic play, but as a living material that responds to every speck of matter.

Two galaxy clusters collided like two swarms of bees flying through each other. One of them is the famous "Bullet." After the collision, the hot gas, which makes up most of the ordinary matter, slowed down and stayed in the center, while the galaxies, like small dense pebbles, flew on.

In the very center of the Milky Way, hidden behind a thick veil of dust, lies a giant accumulation of gas — the Central Molecular Zone. You can't see it with the naked eye: dust absorbs visible light, much like dense fog hides the lights of a city.

Images of distant galaxies are riddled with curved arcs and smears — light warped on its way to us. This effect, predicted by Albert Einstein, acts like a giant funhouse mirror: a massive galaxy cluster distorts the images of background sources.

The kitchen where stars are baked works on a simple recipe: as much flour as you have, that's how many pies you get. For a long time, astronomers saw a strict relation between a galaxy's mass and how fast it forms stars, and they considered it a standalone rule. But a new study of 24,954 nearby galaxies shows that this relation is just a shadow of two more fundamental laws.

In one hospital ward it's +40°C, in another +10°C, and on average it's +25°C. If temperature affected something nonlinearly (say, the rate of bacterial growth) the average would give a wrong prediction. The same problem arises when cosmologists describe a universe where galaxies are packed into clusters and voids yawn between them.

The night sky is full of stars, but they are only a small part of everything that exists in the universe. Astronomers have long noticed a strange thing: galaxies rotate so fast that they should fly apart, yet they don't. Something invisible holds them together, like invisible threads linking beads on a spinning wheel. This "something" was named dark matter.

According to the Big Bang theory, developed by Georges Lemaître, the Universe began from a hot dense point and then rapidly expanded — an inflation proposed by Alan Guth. Echoes of that time reach us as a faint glow — the ancient light.

Astronomers read the history of galaxies by their portraits. Previously, they used either lengthy analysis of light by colors or quick filtered snapshots, losing the details of shape.

Astronomers use Type Ia supernovae — thermonuclear explosions of white dwarfs — as 'standard candles': their peak luminosity was long thought to be the same everywhere in the universe.