Albert Einstein was a German-born physicist who really helped the world see how to view the laws of physics and objects in motion. He is best known for his Theories of Relativity – how objects in the Universe behave in relation to other objects.
These theories brought into question things like ‘is there a central reference point from which to measure all objects behavior?’ For a long time people had wondered if the Universe had a center.
He tells us a lot about the world we live in and it helps us to learn more about ourselves.
What Einstein Said
Before determining or measuring an objects behavior, Einstein first chose to define ‘the stage’ where events in the Universe take place. He chose to define a continuous whole called space-time: made up of space, which has three dimensions, and time, which Einstein said deserves its own dimension.
Einstein’s Concept of Space-time
Space is a vast three-dimensional place in which objects and events have their position and direction. The dimensions are width, height and depth.
Einstein saw that to measure objects mass or velocity, time had to be taken into account. He saw time as so important that he gave it its own dimension, hence the term space-time, a four dimensional continuum. It might be added that more recent theories presume extra dimensions that we do not perceive.
Space-time can be thought of as a grid or fabric and it is the stage that the whole world picture plays out on. In his theories of relativity Einstein suggested that all the world events take place in relation to other events or objects, and that there is no central reference point in the Universe.
Space-time and Gravity
In order to understand the goings-on of the world and Universe we need to be aware of the forces at play in them, like gravity.
Einstein went on to state that the presence of mass distorts space-time, and that objects in space have a gravity, a force of attraction. To demonstrate this he used the rubber sheet model, which is now a popular visualization.
Relativity explains where gravity comes from by using the rubber sheet model. A ball sinks into the rubber sheet (like a trampoline) and thus causes a gravity well, an indented place where the ball sits in the rubber sheet.
A gravity well is the pull of gravity that a large body in space exerts. The larger the body (the more mass) the more of a gravity well it has.
An example of this is the Sun, which has a large (or deep) gravity well. Other smaller asteroids and small moons have much smaller gravity wells. The objects near the gravity well are in relation to this well and are influenced by its pull.
The planets move in ellipses, the most energy-efficient path in the gravity well of the sun.
Time Dilation is a concept introduced by Einstein that shows very well the effect of relativity. It shows how two things that seem the same can have a different outcome or measurement.
People who are subject to different amounts of gravity experience time at relatively different speeds, even though they both seem to be having a similar experience. For both of them time seems to be passing at its normal speed.
A good example of this is: an astronaut who is up in outer space. Einstein showed that the speed of light (186000 Miles per second) is always the same, so it means that the astronaut going very fast relative to the Earth will measure the seconds ticking by slower than an Earthbound observer will. This has to do with gravity’s effect and so time essentially slows down for the astronaut, which is the phenomenon called time dilation.
Referring to the same astronaut, a period of time for someone on Earth that lasts for hundreds of years may only be a couple of hours for someone zooming around in a rocket at close to the speed of light.
This again shows the effect of gravity and is time dilation. Sometimes we can see this when a moving watch runs more slowly than a stationary watch.
Einstein determined that the faster you move through space, the slower you move through time especially the closer you get to the speed of light.
Examples of Relativity
One of Einstein’s major influences was Isaac Newton, an English mathematician, astronomer, theologian, author and physicist. He brought forth some of the ideas that fueled Einstein’s great discoveries.
Newton said that velocities are never absolute, they are always relative. So he said that you had to add the phrase ‘with respect to’, something was true with respect to something else.
An example of Newton was a train traveling forty kilometers per hour:
- The train travels forty kilometers per hour ‘with respect to’ a person standing still.
- Or it travels twenty kilometers per hour ‘with respect to’ a train next to it traveling twenty kilometers per hour in the same direction.
- Or it travels sixty kilometers per hour ‘with respect to’ a train traveling twenty kilometers per hour in the opposite direction.
This is also true of the velocities of Earth, the sun and the entire Milky Way galaxy (our galaxy).
Time and the GPS
Everybody with a smartphone has access to a global positioning system or GPS. When you try to plan a route from “my current location,” your phone needs to connect to a satellite to figure out where “your current location” is.
The satellites are speeding around the Earth at a very fast speed: around 10,000 kilometers per hour (roughly 6213 miles per hour).
It may seem fast, but it is only about a thousandth the speed of light, so you might not think that it’s fast enough for the effects of relativity to take place.
Even at a speed this much slower than the speed of light, the satellite still experiences time dilation: It ages by about 4 microseconds every day, and it experiences the passage of time faster than people on Earth.
When you include the effects of gravity (which also causes time dilation) this figure goes up to about 7 microseconds. This time, 7 microseconds (0.000007 seconds) is a very small time but must be accounted for or your GPS would get you lost very quickly.
After just a day, your location according to the GPS could be up to 8 kilometers (around 5 miles) away from your actual location.
The satellites are programmed to take these effects into consideration when they are planning your route so it usually works out right.
The Two Clocks and Happiness
When we perform tasks in the world we usually relate it to a time clock (the world clock). All through the day we keep track of the tick tick tick on the clock.
Newton thought time was constant and always moving in the same direction: forward. This is a concept that many people still hold today.
Einstein disagreed with Newton and came up with the thought that time stretches and contracts, varying with velocity. This was his idea of the relative in time and so he thought that for this reason time, like space, deserved its own dimension. As we have seen he joined the two together to form the fabric or continuum called spacetime.
He determined that time runs slower on earths surface than it does above the atmosphere, like in outer space. And since different planets have different masses (density) then they have different gravitational strengths, some stronger than the others.
So this means a variable passage of time, and that reflects in aging. For astronauts on the International Space Station, that means they get to age just a little bit slower than people on Earth, and this is because of time-dilation effects.
The Mind Clock
Besides the world clock, we also use our mind clock, our tracking of time within our mind. We think about things and believe that time is passing in its normal way.
But the mind clock and the world clock do not always agree. This is because the use of the two clocks becomes relative, what we think and what the world says is not always the same.
An example of this was a quote by Einstein himself:
‘Put your hand on a stove for a minute and it seems like an hour. Talk to a pretty girl for an hour and it seems like a minute.’
These statements show how things are relative.
So the mind clock and the world clock do not always agree. One thing we know about the mind clock is that:
‘Time flies when you are having fun.’
- Time flies when you move fast and are active or involved in something.
- Time flies when you are with your friends and family and forget about time.
- Time flies when you are thinking of important things and forget that the world exists.
- Time flies when you are sleeping (in another world).
So we have received from Einstein these tools and keys to interpreting the world and Universe and also for helping to know our own minds. We can relax some when we see that the whole thing is not rigid or set in concrete and that is the relative aspect of our world.
We can have fun while we navigate the world and knowledge helps us going towards happiness. When we live in a meaningful and happy way it is the gateway to a life of love and longevity.
So about the question, “Did Albert Einstein Change the World?” we have to say yes he did, he enlightened it!
Side note: Einstein tells us about the world and space-time and the play of objects within it. He says that space is width, height and depth.
In certain Holy scriptures it is said that the world is not real. A spiritual Guru once said that, ‘The idea of depth is an illusion.’ If that was true then it could be that the world is just a dream.
“Only a life lived for others is a life worthwhile.”
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Young Einstein photo credit: By Lucien Chavan