Gravitational Waves: Listening to Space without Templates ⚡ экспресс
Pulsar timing arrays have picked up hints of a low-frequency gravitational-wave background. Searching for waves from specific sources typically requires waveform templates, which limits the search. The new method is template-free: the signal is decomposed into a Fourier series, and a flexible spectral envelope highlights the key frequencies. This allows simultaneously determining the source’s location, its frequency characteristics, and the background level, while also accounting for the pulsars' intrinsic noise. Now we can hear even unexpected signals in the Universe — like a radio receiver tuning into an unknown station.
Astronomers listen to the cosmos like an old radio: they twist the knob not to find a particular station, but to catch any unusual noise. This approach breaks the mold: instead of hunting for gravitational waves using memorized patterns, they catch everything — without bias.
Pulsars are ultra-dense remnants (neutron stars) that spin and beam narrow radio waves into space, like cosmic lighthouses. When a gravitational wave ripples through the universe, it subtly wobbles the very fabric of spacetime (an effect predicted by Einstein), knocking the pulsar’s steady ticking off beat.
This allows them to spot even unexpected waves: the collision of invisible black holes, or ripples left over from the birth of the universe.
🎯 Some pulsars spin hundreds of times per second, and their pulses are more precise than the best atomic clocks.