Profile

Cover photo
Ryan Lanham
Attended Johns Hopkins
Lives in Monesties, Tarn, France
532 followers|46,356 views
AboutPostsPhotosVideos+1's

Stream

 
 
I detect a Rembrandt-like vibe in these portraits.
In an ongoing London exhibition, artist Graham Fink is using an eye tracker to draw portraits, live, using only his eyes. The eye tracker, provided by Tobii Technology, uses infrared light to track...
View original post
1
Add a comment...

Ryan Lanham

Shared publicly  - 
 
 
A planet in the fourth dimension

I bet you know that planets go around the sun in elliptical orbits. But do you know why?

In fact, they’re moving in circles in 4 dimensions. But when these circles are projected down to 3-dimensional space, they become ellipses!  This animation by Greg Egan shows the idea.

The plane here represents 2 of the 3 space dimensions we live in. The vertical direction is the mysterious fourth dimension. The planet goes around in a circle in 4-dimensional space. But down here in 3 dimensions, its ‘shadow’ moves in an ellipse!

What’s this fourth dimension I’m talking about here? It’s a lot like time. But it’s not exactly time. It’s the difference between ordinary time and another sort of time, which flows at a rate inversely proportional to the distance between the planet and the sun.

Egan's animation uses this other sort of time. Relative to this other time, the planet is moving at constant speed around a circle in 4 dimensions. But in ordinary time, its shadow in 3 dimensions moves faster when it’s closer to the sun.

All this sounds crazy, but it’s not some new physics theory. It’s just a different way of thinking about Newtonian physics!  Of course you can see that planets move in elliptical orbits without resorting to the 4th dimension.  But it becomes a lot more obvious if you do!

Physicists have known about this viewpoint at least since 1980, thanks to a paper by the mathematical physicist Jürgen Moser. Some parts of the story are much older. A lot of papers have been written about it.

But I only realized how simple it is when I got a paper in my email from someone I didn't know: an amateur mathematician  named Jesper Göransson.  I get a lot of papers by crackpots, but the occasional gem like this makes up for all those.

The best thing about Göransson’s 4-dimensional description of planetary motion is that it gives a clean explanation of an amazing fact. You can take any elliptical orbit, apply a rotation of 4-dimensional space, and get another valid orbit!

Of course we can rotate an elliptical orbit about the sun in the usual 3-dimensional way and get another elliptical orbit. The interesting part is that we can also do 4-dimensional rotations. This can make a round ellipse look skinny: when we tilt a circle into the fourth dimension, its ‘shadow’ in 3-dimensional space becomes thinner!

In fact, you can turn any elliptical orbit into any other elliptical orbit with the same energy by a 4-dimensional rotation of this sort. All elliptical orbits with the same energy are really just circular orbits on the same sphere in 4 dimensions!

For the details, see the Azimuth blog:

https://johncarlosbaez.wordpress.com/2015/03/17/planets_in_the_4th_dimension/

I had to go through Göransson’s calculations to convince myself that they were right. 

And here is his paper:

• Jesper Göransson, Symmetries of the Kepler problem, 8 March 2015, http://math.ucr.edu/home/baez/mathematical/Goransson_Kepler.pdf.

#physics  
65 comments on original post
1
Add a comment...

Ryan Lanham

Shared publicly  - 
 
Could "open source" join the ranks of food labeling like "organic" and "fair trade"? Revolutionizing American agribusiness from the ground up, one seed at a time.
1
Add a comment...

Ryan Lanham

Shared publicly  - 
 
You will often hear from people who will announce that it's all over, that this is the crisis that ends it, once and for all. The Cassandra sees the end of the road for the project or the brand or...
1
Add a comment...
Have him in circles
532 people
Joe Filceolaire's profile photo
Koketso Zomba's profile photo
Standex-Meder Electronics's profile photo
Salman bahrami nezhad's profile photo
Aarin Paul's profile photo
Compliance Search Group's profile photo
Debayan Kar's profile photo
da khoa phong kham's profile photo
Steve Phelps's profile photo

Ryan Lanham

Shared publicly  - 
 
 
ORIGIN OF LIFE – The Mystery Seems To Be Finally Solved !!!
( Great Breakthrough !!! )

New theory explains how all ingredients of life were formed from very simple chemical components.

Sequential and networking reactions from these basic chemical components are capable of generating all three fundamental characteristics of life: 1) precursors for genetic macromolecules ( RNA ); 2) biomolecules for metabolism; and 3) biochemicals that form a protective lipid membrane to enclose the former chemical structures and chemical processes.

http://phys.org/news/2015-03-chemists-riddle-life-began-earth.html
View original post
1
Add a comment...

Ryan Lanham

Shared publicly  - 
 
So you want to be a Pastafarian. Great. Consider yourself a member. You'll notice there's no hoops to jump through. You don't need to pay anything. How to help the church. You can do that by spreading the word. Tell people about Pastafarianism. Point out that we're the world's most peaceful ...
1
Add a comment...
People
Have him in circles
532 people
Joe Filceolaire's profile photo
Koketso Zomba's profile photo
Standex-Meder Electronics's profile photo
Salman bahrami nezhad's profile photo
Aarin Paul's profile photo
Compliance Search Group's profile photo
Debayan Kar's profile photo
da khoa phong kham's profile photo
Steve Phelps's profile photo
Work
Occupation
Hedge Fund Business Manager
Employment
  • Hedge Fund Business Manager, present
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Monesties, Tarn, France
Previously
3 Waterfall Close, Virginia Water, Surrey - Cincinnati, Ohio - Cayman Islands - Blacksburg, Virginia - Chicago, IL - Boston, MA - Baltimore, MD - Cincinnati, OH - Sea Island, GA - Green Lake, WI
Links
Other profiles
Contributor to
Story
Introduction
I am on Facebook, LinkedIn and Twitter
Bragging rights
Married--happy, two kids.
Education
  • Johns Hopkins
    1981 - 1985
Basic Information
Gender
Male
Ryan Lanham's +1's are the things they like, agree with, or want to recommend.
Physicists find a new way to slow the speed of light
phys.org

(Phys.org)—A team of physicists working at the University of Glasgow has found a way to slow the speed of light that does not involve runnin

Open source revolutionizing American agribusiness | Opensource.com
opensource.com

Could "open source" join the ranks of food labeling like "organic" and "fair trade"? Revolutionizing American agribusiness from the ground u

join « Church of the Flying Spaghetti Monster
www.venganza.org

So you want to be a Pastafarian. Great. Consider yourself a member. You'll notice there's no hoops to jump through. You don't need to pay an

Seth's Blog: Cassandra and Pollyanna
sethgodin.typepad.com

You will often hear from people who will announce that it's all over, that this is the crisis that ends it, once and for all. The Cassandra

Robot researcher combines nature to nurture 'superhuman' navigation | Sc...
www.sciencecodex.com

Computer modelling of the human eye, the brain of a rat and a robot could revolutionise advances in neuroscience and new technology, says a

Here’s what futurist Ray Kurzweil thinks life will be like in the next 2...
www.kurzweilai.net

With companies like Google creating self-driving cars and augmented-reality glasses, futurist Ray Kurzweil's predictions are starting to sou

googleVis 0.5.5 released
www.r-bloggers.com

Earlier this week we released googleVis 0.5.5 on CRAN. The package provides an interface between R and Google Charts, allowing you to create

Permaculture – Récolte pommes de terre octobre 2013
www.permapi.fr

Pommes de terre plantées peu profond dans un sol non travaillé, légèrement buttées et recouvert de 10 cm de paille. Non désherbées de la sai

Seth's Blog: Go first
sethgodin.typepad.com

Before you're asked. Before she asks for the memo, before the customer asks for a refund, before your co-worker asks for help. Volunteer. Of

The Curious Wavefunction: The structure of DNA, 61 years later: How they...
wavefunction.fieldofscience.com

This month marks the sixty-first anniversary of the publication of the landmark paper on the structure of DNA by Watson and Crick, which app

Disruptive Healthcare Start-up Oscar Raises $80 Million, Valuation Nears...
www.forbes.com

Oscar has raised an $80 million investment round. Sources close to the deal say the round valued Oscar at $800 million.

An ultra-sensitive chip for early cancer detection | KurzweilAI
www.kurzweilai.net

The ICFO lab-on-a-chip (credit: ICFO) An international team of researchers, led by ICFO - Institute of Photonic Sciences in Castelldefels, h

God Is in the Mind. Well, in Epileptic Seizures to Be Exact. | IdeaFeed ...
bigthink.com

Our medical knowledge of cerebral dysfunctions like epilepsy is casting new light on some famously religious characters like Joan of Arc, Sa

The Crazy Diversity of Animal Skulls, From Hippos to Hummingbirds | Scie...
www.wired.com

You can tell a lot about the life an animal lived by looking at its skull. Big eye sockets point to a nocturnal lifestyle (big eyes harvest

Scientists create new lifeform with added DNA base pair | KurzweilAI
www.kurzweilai.net

(Credit: iStock) Scientists at The Scripps Research Institute (TSRI) have engineered a bacterium whose genetic material includes an added pa

The 3% solution
www.economist.com

PEOPLE are living longer, which is good. But old age often brings a decline in mental faculties and many researchers are looking for ways to

Ask Ars: Why are some programming languages faster than others?
arstechnica.com

Scientists use Fortran because it's fast, but what makes it so?

This is What Rock Climbing Bears Looks Like
twistedsifter.com

Just add this to the long list of reasons bears are awesome. These guys can rock climb better than me and I have opposable thumbs! Spotted a

A new self-assembling graphene-like material for flat semiconductors | K...
www.kurzweilai.net

A diagram of the molecular structure of the new material shows how it naturally forms a hexagonal lattice structure, and its two-dimensional