Popular Mechanics - USA (2022-03 & 2022-04)

32 March/April 2022

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Physics

7

// BY CAROLINE DELBERT //

This Is the Closest

Scientists Have

Gotten to Reaching

Absolute Zero

R

ESEARCHERS FROM FOUR UNIVERSITIES

in Germany have conditioned a lab to

register the coldest effective temperature

in a research-controlled environment

ever recorded—38 trillionths of a Kelvin

above absolute zero. According to a 2021

study published in the journal Physi-

cal Review Letters, the temperature persisted for

two seconds at the University of Bremen’s Center

of Applied Space Technology and Microgravity

(ZARM), and the conditions that made this pos-

sible could have longstanding ramifications for

quantum mechanics.

Absolute zero is 0 Kelvin, equal to –273.15

degrees Celsius, or –459.67 degrees Fahrenheit.

This is the point at which particles are essen-

tially motionless, and it’s the lowest possible

The absolute

temperature scale

gives measurements in

Kelvins—unlike Celsius

and Fahrenheit, which

use degrees. Absolute

zero is thus 0 Kelvin,

not 0 degrees Kelvin.