Monday , May 29 2023

This new atomic clock is so precise that our ability to measure gravity limits its accuracy


NIST is the most accurate time that the optical atomic clock maintains. Image: NIST

Researchers at the National Institute of Standards and Technologies (NIST) have developed an atomic clock, which is so specific that the Earth's gravity model is not enough. As is determined in a paper published this week Nature , The atomic clock can extend the unpredictability of the Earth's gravity that distorts space time and unleashes an unprecedented map that illuminates the development of the early universe.

"The performance level of the clock is reported, so we do not really know how to get enough performance to achieve performance," said Andrew Ludlow, physicist NIST and the atomic clock about the new project organization. "Today, as the state of art techniques is not enough, we have a similarity to the gravity of different parts of the Earth."

Thanks to the nitty famine of Ludlow's and NIST's colleagues, it will help keep the time and atomic clocks behind.


Regardless, if your university members say you press Bong, as most scientists measure real-time occurrences. In other words, it is a time-consuming thing, also known as a clock. Sometimes regular events can be quite a clock, such as the swing of pendulum, around the Earth's rotation axis, or the philosopher Emanuel Kant taking a walk around his neighborhood.

Obviously, all the clocks do not create the same. Each field changes according to its precision (the degree of oscillation frequency is diverted) and its time scale. If you were to measure the passage of five minutes, using the Earth's rotation will not be particularly useful as a watch. Also, if you have never had your care, it would gradually be gradually less determined due to minor errors in the mechanics.

Most of us are times and years, which does not require very accurate clocks. However, scientists working on the physique's bleeding edge need more accurate measurements of time. Fortunately, nature has had very specific identical clocks in the form of an atomic energy transition.

The electrons orbit the nucleus of an atom over certain electrical energy levels based on the electrical properties of the nucleus. These orbitals are added to the electrical system, resulting in the transition of the electrons to a higher level of energy and the emission of electromagnetic radiation. Different types of atoms can be absorbed in a variety of wavelengths, and this is used to create specific watermarks in the world.

Read more: Why the Nuclear Areas will be the Concrete Clocks of the Earth

The first atomic clock that emerged in 1955 and the energy transition of the electrons is a frequent reference for the atomic cesium 133. The atomic-133 atoms absorb energy at a wavelength of 3.2 cm, that is, the waves oscillate Frequency: 9.192.631.770 cycles per second. When cesium-133 atoms dwindle through microwaves, this frequency causes a single outer electron of the atom to cause more rapid transition between energy states. In this case, the transition between electrical energy and low electric energy is similar to 9,000 million times a second time. In fact, the cesium-133 electron transition was used Formally specifies the second length of 1967.

Currently, four atomic clocks can be found on the Earth's orbit 24 GPS satellites, and are used to synchronize our mobile phones and millions of Internet connections on other devices. They are also used to measure a sea level to understand how the space time of our planet's gravity is understood. Knowing this information makes it necessary to calibrate the atomic clocks in the space, but with the accuracy of these clocks – the NIST has an atomic clock deviating only one second 200 million per year – there is always room for improvement.

In this sense, the new NIST atomic clock is delivered more than once. It is so necessary that the current pattern of Earth's gravity can not continue. Fortunately, the new clock will help this change.

Andrew Ludlow in the laboratory.

Andrew Ludlow works at the NIST laboratory atomic clock. Image: NIST


It's the best question, but also the most difficult difficulty for physicists. The reason for this is that, as Einstein found, time is not absolute. Rather the passage of time is relative. It depends on the frame of the reference of the observers, like things like their speed and the force of gravity that are like in their frame of reference. For example, a person about a strong gravitational field, such as a black hole, moves more slowly than a person standing in the Earth's surface.

Humans experience time in the days of macroscale, in hours, in minutes, and in everyday life, we are not moving fast enough or moving in a gravitational field with enough force to move on such a rapid or slow change. However, when I climb the stairs in the afternoon in my apartment, it's time is there I agree or not.

"It's a little effect," Ludlow said. "Creepy type is authentic, but that's it."

Read more: Balkan Energy War Europe Watches were slowed down for five minutes

I climb every step, moving from the Earth's gravity center more distant, which means that the effect of gravity decreases the frequency of the oscillators that I use as a clock. The physicist calculates how gravity affects time in the highest clock on the earth's surface and the second rising above the clock at 1.1 out of every one centimeter per vertical. In other words, a second measured on the Earth's surface actually takes a further 0.000000000000000011 second seconds on a Earth-centimeter clock and so on.

Of course, "Earth's surface" is a beak, because it can be somewhat different depending on the area. The summit of Death Valley and Mount Everest are technically the Earth's surface, but a 282-foot sea level and the other from 29,000 feet above sea level. For this reason, "sea level" is also a constant flow due to tide changes.

To address this problem, scientists understand Earth as "geoidea". The hypothetical form of the Earth is that the oceans were only by force of the Earth's rotation and gravity and spread throughout all continents. That is, the equivalent of the average sea level on the Earth, that is, based on ocean-based sensors and satellite data. When the Geooid is displayed, it looks like this:

The geoid is great for measuring the Earth's surface height to measure high accuracy, but it creates problems for the creation of ultra-precise watches. The reason for this is that the Earth is not exactly a geoid and elevation differences that induce significant gravitational effects of time measurement. That is, in most cases, when distances are separated by long distances, such as GPS satellites.

Although scientists consider these differences in gravity on Earth, geopolitical heights are also called using atomic satellite watches, which can be diverted by 0.0000000000000001 seconds, equal to the change in the elevation of 0.9 meters. The new atomic clock developed by the NIST, however, is very accurate to reduce this change in one centimeter, that is, 1.4 parts of eleven parts (18 zeros).

According to Ludlow, this progress was only possible due to the revolutionary nature of the clock. The atomic clocks used by the NIST for research have atomic atoms in a laser tube. Although it has been a harsh technology, many physicists have been acquainted with this technology for years, but have taken advantage of this technology to take care of these optical atomic clocks. In fact, Ludlow said his latest breakthrough is the end of a few years, investigating how to limit the interference of similar electrical and magnetic field fields.

Ludlow told me that the NIST atomic clock is a wall that is a scientific door. In this sense, a wall is so precise that the current geoid measurements that combine accuracy of the atomic clock, as the geopotential scheme of many centimeters gives it, while the clock reduces the geopotential absorption within a few centimeters. On the other hand, the NIST atomic clock gate is used to improve geodesic resolution several times. This entails the distribution of some of these clocks around the world, and should take some time to deviate as long as the Earth's gravity space has lasted as much as possible for the largest map.

"If you trusted trustworthy watches at a very high level, then you can use clocks as a potential gravity sensor in the Earth if changes to the chimney changes to a clock through different parts of the Earth. Gravitate," said Ludlow.

Ludlow said, and its NIST colleagues are currently working on prototyping to use their portable versions of atomic clocks to test that idea. It will be several years before the Earth or space, but the NIST clock can be used for other uses, for example, for the second to be more accurate.

Source link