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einstein-text-pixa

“Imagination is more important than knowledge.” ― Albert Einstein

Knowledge versus imagination. Einstein spent the latter part of his life pursuing a “single, all encompassing theory of the universe.”  He wanted to able to describe all of nature’s forces – to explain it all. He didn’t find it.

James Taylor sings in “Secret of Life

Now the thing about time
Is that time isn’t really real.
It’s just your point of view,
How does it feel for you?
Einstein said he
Could never understand it all.
Planets spinning through space,
The smile upon your face,
Welcome to the human race.

That Einstein quote at the top of this article continues “…for knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.” Imagination is often the pathway to increasing knowledge.

It is interesting that astronomy experiments now might test an idea of Einstein’s that he proposed almost exactly a century ago. It has been a longstanding question of why the Universe is expanding at an accelerated rate. Calculations in a new study could help to explain whether dark energy, as required by Einstein’s theory of general relativity, or a revised theory of gravity are responsible.

Einstein wasn’t a big fan of a lot of the physics that came at the end of his life, and would probably not be a fan of string theory.

Brian Greene is a professor of mathematics and physics at Columbia University who is probably best-known to the public for his NOVA television specials. He is one of the best “explainers” of this deep science. He explains string theory and I can understand it – until he stops explaining it and I have to tell someone else what he meant. The idea of minuscule filaments of energy vibrating in eleven dimensions that make up the “fabric of space.. and create every particle and force in the universe” is not easy to understand or accept.

String theory fills in the gaps of Newtonian physics, especially regarding how gravity works, and Einstein’s Unification Theory depends on the existence of extra dimensions, which contain these filaments and some string theorists posit that there are at least eleven dimensions. For all of us used to living in four dimensions, that is tough to imagine.

James Gates is known for work on supersymmetry, supergravity, and superstring theory. When he was asked about Einstein’s statement that “imagination is more important than knowledge,” he said“For a long time in my life, imagination was the world of play. It was reading about astronauts, and monsters, and traveling in galaxies, all of that kind of stuff, invaders from outer space on earth. That was all in the world of the imagination. On the other hand, reality is all about us. And it’s constraining, and it can be painful. But the knowledge we gain is critical for our species to survive.”

 


Brain Greene on string theory

flatland

Sure, you are comfortable in your little 3D world. But what if we are all 3D projections of a 2D universe? That’s what the holographic principle suggests.

Our 4D Universe (height, length, depth, and don’t forget about time) make up spacetime. That’s where all our theories about matter and the cosmos reside. But there are other theories – like string theory.

String theory proposes a lot more than those 4 dimensions. In Brian Greene’s The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos, he suggests a holographic multiverse of 11 dimensions.

Imagine a multiverse in which you have an infinite number of doppelgängers. Each of you is reading this blog post in a distant universe. The multiverse has may bubble universes, and the one you think you are living in is but one. Some of those universes move differently through time. One might be very close to this one, but remains invisible to us. The multiverse could be made purely of math.

The holographic principle might tell us that one of the ordinary three dimensions of space is unnecessary to understand this universe. Maybe, like a hologram, the information we call “depth” might be encoded in the other dimensions.

starwarshologram
On the Nature website there is an article headlined “Simulations back up theory that Universe is a hologram.”

Headlines aside, the universe is not a hologram, at least not in the way most people think of holograms – perhaps as some character in Star Wars. The is “holographic universe” comes from string theory and currently isn’t any experimental evidence to support string theory. And some people claim they have evidence against string theory being valid. Right or wrong, it is of interest and it is interesting.

As far as I could find, the holographic principle starts in 1993 with Gerard t’Hooft. Even in simple language, it is complicated. He proposed that the information contained within a region of space can be determined by the information at the surface that contains it, and mathematically the space can be represented as a hologram of the surface that contains it. Get it?  Me neither.

In another article that argues that the universe is not a hologram, the author uses this example:

… suppose there is a road 10 miles long, and its is “contained” by a start line and a finish line. Suppose the speed limit on this road is 60 mph, and I want to determine if a car has been speeding. One way I could do this is to watch a car the whole length of the road, measuring its speed the whole time. But another way is to simply measure when a car crosses the start line and finish line. At a speed of 60 mph, a car travels a mile a minute, so if the time between start and finish is less than 10 minutes, I know the car was speeding.

If I ever gave any serious thought to the dimensions of our world in my younger years, I suspect it was when a teacher showed our class a short film based on the book Flatland: A Romance of Many Dimensions.

It is an 1884 satirical novella by the English schoolmaster Edwin Abbott who published it under the pseudonym “A Square.” Abbott intended the book to comment on the hierarchy of Victorian culture, in the same way that Swift’s Gulliver’s travels was meant as satire. But the book has held on more as an examination of dimensions.

Here’s Abbott’s original dedication:

To The Inhabitants of SPACE IN GENERAL And H. C. IN PARTICULAR This Work is Dedicated By a Humble Native of Flatland In the Hope that Even as he was Initiated into the Mysteries Of THREE Dimensions Having been previously conversant With ONLY TWO So the Citizens of that Celestial Region May aspire yet higher and higher To the Secrets of FOUR FIVE OR EVEN SIX Dimensions Thereby contributing To the Enlargement of THE IMAGINATION And the possible Development Of that most rare and excellent Gift of MODESTY Among the Superior Races Of SOLID HUMANITY

There are lots of print versions of Flatland and you can read it online.

The film I saw as a kid was a short, but there are a few versions including a feature film Flatland: The Movie.

In Flatland, a two-dimensional world occupied by geometric figures, women are simple line-segments and men are polygons with various numbers of sides. The narrator is a square, a member of the caste of gentlemen and professionals, who guides the readers through life in two dimensions.

The Square dreams about visiting a one-dimensional world called Lineland that is inhabited by points. While there, he tries their leader that there is a second dimension. He can’t do it because the inhabitants cannot imagine another dimension beyond their own.

When Square is visited by a three-dimensional sphere, he cannot comprehend it.

Finally, he sees Spaceland which has three dimensions. Square’s mind is opened to the idea of new dimensions. He tries to convince the Sphere a fourth or even fifth, sixth or more dimensions might exist but that is not an idea that the Sphere can accept.

When Square returned to Flatland, he can’t convince anyone that Spaceland exists. His existence prompts official decrees that anyone preaching the existence of three dimensions will be imprisoned and eventually that’s what happens to Square.

Square would be pleased to see this video with Michio Kaku called “The Multiverse Has 11 Dimensions.”

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