Astronomers have long theorised about the connection between a white dwarf star mass & radius but haven’t been ready to observe the stars mass-radius relationship so far , a recent study shows. As white dwarf stars gain mass, they shrink in size unlike most known celestial objects.
In this new work, researchers used a completely unique method that incorporated data from thousands of white dwarfs to watch the strange phenomenon and supply further evidence for the idea of general theory of relativity .
When stars like our sun run out of fuel, they shed their outer layers & are stripped right down to their Earth-sized core. This core is understood as a white dwarf star star, which is believed to be the ultimate evolutionary state of a stellar object.
But these stellar remnants hold a mystery, as when white dwarfs increase in mass, they shrink in size. White dwarfs therefore will find yourself with a mass almost like that of the sun, but packed into a body the dimensions of the Earth .
White dwarfs become so small and compact that they eventually collapse into neutron star, highly dense stellar corpses with a radius that sometimes doesn’t extend beyond 18 miles (30 km).
The odd mass-radius relationship within white dwarf star stars has been theorised about since the 1930s. The rationale why white dwarf star increase in mass while shrinking at same time is assumed to be caused by the state of its electrons — as a white dwarf star is compressed, the amount of its electrons increases.
This mechanism may be a combination of quantum physics a fundamental theory in physics on the motion & interaction of subatomic particles — also as Albert Einstein theory of general theory of relativity , which deals with gravitational effects.
“The mass-radius relation may be a spectacular combination of quantum physics and gravity, but it’s counterintuitive for us,” Nadia Zakamska, an professor at the Department of Physics and Astronomy at Johns Hopkins University, who supervised the new study, said during a statement. “We think as an object gains mass, it should get bigger.”
In this new study, the team from John Hopkins University developed a way to study the mass-radius relationship in white dwarfs. Using data collected by the Sloan Digital Sky Survey and therefore the Gaia Space Observatory, the researchers checked out 3,000 white dwarf stars.
The team of researchers measured the gravitational redshift effect, which is that the effect of gravity on light, on the celebs . As light moves faraway from an object, the wavelength of light coming from the thing lengthens, causing it to seem redder. By watching the gravitational redshift effect, they were ready to determine speed of the white dwarf star stars that share an identical radius.
Radial velocity is that the distance from the Sun to a given star which determines whether a star is moving towards or faraway from the Sun. By determining the stars radial velociy (speed) , they were also ready to determine the change within the stars mass.
“The theory has existed for long-time, but what’s notable is that the dataset we used is of unprecedented size & unprecedented accuracy,” Zakamska added. “These measurement methods, which in some cases were developed years ago, all of a sudden work such a lot better and these old theories can finally be probed.”
The method utilized in the study essentially turned a theory into an observational phenomenon. Additionally, it are often wont to study more stars within the future, and may help astronomers analyze the chemical composition of white dwarf stars.
“Because the star gets smaller because it gets more massive, the gravitational redshift effect also grows with mass,” Zakamska said. “And this is often a touch easier to comprehend—it’s easier to urge out of a less dense, bigger object than it’s to urge out of a more massive, more compact object. And that is exactly what we saw within the data.”