What is time?

April 13, 2005

The concept of time is self-evident. An hour consists of a certain number of minutes, a day of hours and a year of days. But we rarely think about the fundamental nature of time.
Time is passing non-stop, and we follow it with clocks and calendars. Yet we cannot study it with a microscope or experiment with it. And it still keeps passing. We just cannot say what exactly happens when time passes.

Time is represented through change, such as the circular motion of the moon around the earth. The passing of time is indeed closely connected to the concept of space.

According to the general theory of relativity, space, or the universe, emerged in the Big Bang some 13.7 billion years ago. Before that, all matter was packed into an extremely tiny dot. That dot also contained the matter that later came to be the sun, the earth and the moon – the heavenly bodies that tell us about the passing of time.

Before the Big Bang, there was no space or time.

“In the theory of relativity, the concept of time begins with the Big Bang the same way as parallels of latitude begin at the North Pole. You cannot go further north than the North Pole,” says Kari Enqvist, Professor of Cosmology.

One of the most peculiar qualities of time is the fact that it is measured by motion and it also becomes evident through motion.

According to the general theory of relativity, the development of space may result in the collapse of the universe. All matter would shrink into a tiny dot again, which would end the concept of time as we know it.

“Latest observations, however, do not support the idea of collapse, rather inter-galactic distances grow at a rapid pace,” Enqvist says.

Source: University of Helsinki

Explore further: 'Statistics anxiety' is real, and new research suggests targeted ways to handle it

Related Stories

Novel viral identification method developed

January 16, 2019

Currently, influenza typing in clinical practice is performed using an immunochromatography method based on antigen-antibody interaction. This method enables simple diagnosis of infectious diseases. However, it also has a ...

Technique boosts omega 3 fatty acid levels in brain

January 8, 2019

Getting enough of the omega 3 fatty acids DHA and EPA into the brain to study their effects on conditions such as Alzheimer's and depression—which they have been shown to help—is no easy task. While supplements containing ...

Best of Last Year—The top Phys.org articles of 2018

December 21, 2018

It was another great year for science, and physics was front and center, as a team at the University of Oxford announced that they may have solved one of the biggest mysteries in modern physics. They came up with a new theory ...

Perspectives on gene editing

January 10, 2019

Medicine is at a turning point, on the cusp of major change as disruptive technologies such as gene, RNA, and cell therapies enable scientists to approach diseases in new ways. The swiftness of this change is being driven ...

Recommended for you

A boost for photosynthesis

January 24, 2019

Photosynthesis is a fundamental biological process by which plants use light energy for growth. Most life forms on Earth are directly or indirectly dependent on photosynthesis. Researchers at the Max Planck Institute of Biochemistry ...

How gender inequality is reproduced on social media

January 24, 2019

Researchers from the Higher School of Economics analyzed 62 million public posts on the most popular Russian social networking site VK and found that both men and women mention sons more often than daughters. They also found ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.