Understanding Time & Gravity

We doubt even physicists really understand how time and gravity work. These sites, however, give you a glimpse into it all.

What Is Time?

Thomas Kitching, a cosmologist and astrophysics lecturer, looks at questions like: Does time have a beginning? Time's arrow? Will time end?

Written in non-technical language, this post gives you an idea of the questions scientists are looking at.

larger image of https://www.nist.gov/pml/walk-through-time-ancient-calendars

image of https://www.nist.gov/pml/walk-through-time-ancient-calendars

This on-line essay on the history of timekeeping was conceived and written by Kent Higgins and illustrated by Darwin Miner, of the Program Information Office of the National Bureau of Standards (now NIST). Originally penned in 1975, it has been updated numerous times over the years.

Time Zones

This site provides an overview of Time Zones, what are they and why we have so many of them.

Who knew the International Date Line created 3 extra time zones.

Strangest Time Zones of the World

This video looks at some of the world's strangest time zones, including: China, Kiribati, Nepal, Australia and more.

YouTube URL: https://www.youtube.com/watch?v=uW6QqcmCfm8

larger image of http://www.navy.mil/navydata/questions/bells.html

image of http://www.navy.mil/navydata/questions/bells.html

Time as marked by the bells

You've heard the phrase, "8 bells and all is well." This resource shows you where that saying originated.

Not everyone uses a display to tell the time.

How Gravity Makes Things Fall

A demonstration of gravity, featuring the "Spacetime Stretcher," built mostly out of materials from the garage and hardware store. Click on the YouTube logo to view the About section containing additional details. Would make a great classroom or science fair project.

YouTube URL: https://www.youtube.com/watch?v=jlTVIMOix3I

Telling Time for Young Children

There are a number of videos helping kids learn to tell time. This is one of our favorites.

YouTube URL: https://www.youtube.com/watch?v=HrxZWNu72WI

larger image of http://archive.ncsa.illinois.edu/Cyberia/NumRel/NumRelHome.html

image of http://archive.ncsa.illinois.edu/Cyberia/NumRel/NumRelHome.html

Space-Time Wrinkles

Space-Time Wrinkles uses photos from a supercomputer to explain black holes and gravity ala Einstein (including all the hairy math equations).

NIST

Major concepts and a history of time-keeping can be found at the NIST site.

Like other resources in this library, these sites advances traditional curriculum by asking a meta-questions: Who sets the time on our globe? How was the time set in history? What is global time (rather than a student's local time)? In other words, students can go beyond the descriptive to the analytical.