Invisibility: Theory and Practice - v2

http://timeandquantummechanics.comInvisibility: Theory & Practice - FOSSCON, Aug 10th 2013

Invisibility:Theory & Practice

John Ashmead

Friday, August 9, 13

http://timeandquantummechanics.comInvisibility: Theory & Practice - FOSSCON, Aug 10th 2013

Invisibility:Theory & Practice

John Ashmead

Newly updated for FOSSCON!

Invisibility: Theory & Practice - FOSSCON, Aug 10th, 2013 http://timeandquantummechanics.com

Transparent Motives

•Wicked cool

Transparent Motives

•Wicked cool

•Very practical: not just for war anymore!

Transparent Motives

•Wicked cool

•Very practical: not just for war anymore!

•And of great scientific value

Outline

•A brief history of invisibility

Outline

•Reflections on materials

Outline

•Reflections on materials

•War, peace & the future

The Invisible Man

“If a sheet of glass is smashed, Kemp, and beaten into a powder, it becomes much more visible while it is in the air; it becomes at last an opaque white powder. This is because the powdering multiplies the surfaces of the glass at which refraction and reflection occur. In the sheet of glass there are only two surfaces; in the powder the light is reflected or refracted by each grain it passes through, and very little gets right through the powder. But if the white powdered glass is put into water, it forthwith vanishes. The powdered glass and water have much the same refractive index; that is, the light undergoes very little refraction or reflection in passing from one to the other.” -- Griffin…

“Yes, yes,” said Kemp. “But a man's not powdered glass!”

Sucker Bet

The last cry you hear could be “Mimicry”

Yellow touches red, you be dead. Red touches black, eat Cracker Jacks.

Spicebush swallowtail

Camouflage

“The soldiers of France will never abandon their pantaloons rouge!”

Camouflage

Modern camouflage began in 1915, when, after a crushing defeat by the Germans, the French army abandoned their stylish white gloves and red pantaloons and enlisted a cadre of artists to develop stealthier attire. The U.S. followed suit in 1917. In addition to hand-painted uniforms, these camoufleurs created false bridges, decoy tanks, and, as seen above, paper-mache horse carcasses that snipers used as blinds.

Dazzle

•Ships in WWI & WWII

Dazzle

•Confusion to the enemy

Dazzle

•Moral boost at least

Dazzle

•Moral boost at least

Stealth

Why so Boxy?

•Reflections angle away from source

Why so Boxy?

•Also, paint eats radar waves

Why so Boxy?

•But, hard to fly

Why so Boxy?

•But, hard to fly

•And, crashes a lot

Invisibility: Theory & Practice - FOSSCON, Aug 10th, 2013 http://timeandquantummechanics.comFriday, August 9, 13

Pay no attention…

Physics of invisibility

•Invisibility cloaks

•Negative refractive indexes

•Metamaterials

•Optical transformations

•Metamaterials

•Optical transformations

•General relativity helps make it simple?

Invisibility Cloaks

Invisibility in Practice

“Invisibility is theoretically possible captain – the selective bending of light – but the power cost is enormous. They may have solved that problem”

– Lt. Cmdr. Spock

Lighten Up!

•Slow light

Lighten Up!

•Slow light

•Light that goes faster than light

Lighten Up!

•Slow light

•Stopped light - light that doesn’t go at all

Lighten Up!

•Slow light

•Stopped light - light that doesn’t go at all

•Backwards light

Cat’s eyes

Fermat’s principle

Direct but slow

Faster

Fermat’s principle

Direct but slow

Faster

Fastest!

Simple Lens

Lüneberg Lens

PositiveRefraction

Negative Refraction

http://www.loa.espci.fr/cargese2009/Cargese2009_Pendry.pdfInvisibility: Theory & Practice - FOSSCON, Aug 10th 2013

Time Reversal

Negative cancels positive

Super lens

Invisibility: Theory & Practice - FOSSCON, Aug 10th, 2013 http://timeandquantummechanics.comFriday, August 9, 13

http://www.loa.espci.fr/cargese2009/Cargese2009_Pendry.pdfInvisibility: Theory & Practice - FOSSCON, Aug 10th 2013Friday, August 9, 13

Warping space

http://www.loa.espci.fr/cargese2009/Cargese2009_Pendry.pdfInvisibility: Theory & Practice - FOSSCON, Aug 10th 2013Friday, August 9, 13

Like water around a rock…

Hiding a lump under the carpet

Invisible Tanks

Foreseeable Civilian Uses …

•Traffic light visibility

•Earthquake & tsunami avoidance

•Locating reactor core with muons

•Tourist revenue enhancement…

Black holes in the laboratory

Black holes as lenses

Einstein Rings

Time Cloak

How to Vanish a Cat

The apparatus uses the fact that the human eye can’t see phase information to help route light around the “space between”. With no need to preserve the phase, the design is much simpler!

Only works from a few directions, alas.

http://arxiv.org/abs/1306.1780

Seeing the invisible

•It’s all about the math (really the information!)

•Brains at play

•Any sufficiently advanced science will look like magic

Be Seeing You

Be Seeing You•Forbes - Dazzled & Deceived - 2009 [Fun]

•Perkowitz - Slow Light: Invisibility, Teleportation, & Other Mysteries of Light - 2011 [Solid]

•Beech - Physics of Invisibility: A Story of Light & Deception - 2011 [Lots of pictures]

•Leonhardt - Geometry & Light: Science of Invisibility - 2010 [Brain-Frier]

Invisibility: Theory and Practice - v2

Technology

Invisibility cloaks and transformation optics

Invisibility Cloak

2011 Invisibility Cloaking

AntiGravity Invisibility

Refractions and Translator's Invisibility - George

Invisibility Cloaking

Invisibility Cloaks via Non-Smooth Transformation Optics and Ray Tracingeaton.math.rpi.edu/CSUMS/Papers2/Invisibility/cloak.pdf · 2011. 2. 11. · Invisibility Cloaks via Non-Smooth

OPTICAL CAMOUFLAGE - Invisibility Cloak. Optical Camouflage-Invisibility Cloak PREMJITH P.G S7, EEE 1

Light Fantastic - Flirting with Invisibility

200041980 Basic Theory Wcdma v2

Report on Invisibility

Invisibility of Mexican Migrant Workers

Invisibility: Theory & Practice - v3

Visible Invisibility

FELDMAN, Ilana - Refusing Invisibility (Original)

Some Aspects of Invisibility

Invisibility: Theory & Practice

Embedded Videos: from Invisibility to Visibility

The Power of Invisibility

Invisibility for Muggles!